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qemu/target/riscv/csr.c

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RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/*
* RISC-V Control and Status Registers.
*
* Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
* Copyright (c) 2017-2018 SiFive, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2 or later, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "cpu.h"
#include "qemu/main-loop.h"
#include "exec/exec-all.h"
/* CSR function table */
static riscv_csr_operations csr_ops[];
/* CSR function table constants */
enum {
CSR_TABLE_SIZE = 0x1000
};
/* CSR function table public API */
void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops)
{
*ops = csr_ops[csrno & (CSR_TABLE_SIZE - 1)];
}
void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
{
csr_ops[csrno & (CSR_TABLE_SIZE - 1)] = *ops;
}
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
/* Predicates */
static int fs(CPURISCVState *env, int csrno)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
return -1;
}
#endif
return 0;
}
static int ctr(CPURISCVState *env, int csrno)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Add support for disabling/enabling Counters Add support for disabling/enabling the "Counters" extension. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:22 +08:00
CPUState *cs = env_cpu(env);
RISCVCPU *cpu = RISCV_CPU(cs);
uint32_t ctr_en = ~0u;
if (!cpu->cfg.ext_counters) {
/* The Counters extensions is not enabled */
return -1;
}
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
/*
target/riscv: Add support for disabling/enabling Counters Add support for disabling/enabling the "Counters" extension. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:22 +08:00
* The counters are always enabled at run time on newer priv specs, as the
* CSR has changed from controlling that the counters can be read to
* controlling that the counters increment.
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
*/
if (env->priv_ver > PRIV_VERSION_1_09_1) {
return 0;
}
target/riscv: fix counter-enable checks in ctr() Access to a counter in U-mode is permitted only if the corresponding bit is set in both mcounteren and scounteren. The current code ignores mcounteren and checks scounteren only for U-mode access. Signed-off-by: Xi Wang <xi.wang@gmail.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-27 07:02:56 +08:00
if (env->priv < PRV_M) {
ctr_en &= env->mcounteren;
}
if (env->priv < PRV_S) {
ctr_en &= env->scounteren;
}
if (!(ctr_en & (1u << (csrno & 31)))) {
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
return -1;
}
#endif
return 0;
}
#if !defined(CONFIG_USER_ONLY)
static int any(CPURISCVState *env, int csrno)
{
return 0;
}
static int smode(CPURISCVState *env, int csrno)
{
return -!riscv_has_ext(env, RVS);
}
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
static int hmode(CPURISCVState *env, int csrno)
{
if (riscv_has_ext(env, RVS) &&
riscv_has_ext(env, RVH)) {
/* Hypervisor extension is supported */
if ((env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
env->priv == PRV_M) {
return 0;
}
}
return -1;
}
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
static int pmp(CPURISCVState *env, int csrno)
{
return -!riscv_feature(env, RISCV_FEATURE_PMP);
}
#endif
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* User Floating-Point CSRs */
static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
#endif
RISC-V: Use riscv prefix consistently on cpu helpers * Add riscv prefix to raise_exception function * Add riscv prefix to CSR read/write functions * Add riscv prefix to signal handler function * Add riscv prefix to get fflags function * Remove redundant declaration of riscv_cpu_init and rename cpu_riscv_init to riscv_cpu_init * rename riscv_set_mode to riscv_cpu_set_mode Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:23 +08:00
*val = riscv_cpu_get_fflags(env);
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
static int write_fflags(CPURISCVState *env, int csrno, target_ulong val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
env->mstatus |= MSTATUS_FS;
#endif
RISC-V: Use riscv prefix consistently on cpu helpers * Add riscv prefix to raise_exception function * Add riscv prefix to CSR read/write functions * Add riscv prefix to signal handler function * Add riscv prefix to get fflags function * Remove redundant declaration of riscv_cpu_init and rename cpu_riscv_init to riscv_cpu_init * rename riscv_set_mode to riscv_cpu_set_mode Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:23 +08:00
riscv_cpu_set_fflags(env, val & (FSR_AEXC >> FSR_AEXC_SHIFT));
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
static int read_frm(CPURISCVState *env, int csrno, target_ulong *val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
#endif
*val = env->frm;
return 0;
}
static int write_frm(CPURISCVState *env, int csrno, target_ulong val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
env->mstatus |= MSTATUS_FS;
#endif
env->frm = val & (FSR_RD >> FSR_RD_SHIFT);
return 0;
}
static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
#endif
RISC-V: Use riscv prefix consistently on cpu helpers * Add riscv prefix to raise_exception function * Add riscv prefix to CSR read/write functions * Add riscv prefix to signal handler function * Add riscv prefix to get fflags function * Remove redundant declaration of riscv_cpu_init and rename cpu_riscv_init to riscv_cpu_init * rename riscv_set_mode to riscv_cpu_set_mode Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:23 +08:00
*val = (riscv_cpu_get_fflags(env) << FSR_AEXC_SHIFT)
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
| (env->frm << FSR_RD_SHIFT);
return 0;
}
static int write_fcsr(CPURISCVState *env, int csrno, target_ulong val)
{
#if !defined(CONFIG_USER_ONLY)
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
env->mstatus |= MSTATUS_FS;
#endif
env->frm = (val & FSR_RD) >> FSR_RD_SHIFT;
RISC-V: Use riscv prefix consistently on cpu helpers * Add riscv prefix to raise_exception function * Add riscv prefix to CSR read/write functions * Add riscv prefix to signal handler function * Add riscv prefix to get fflags function * Remove redundant declaration of riscv_cpu_init and rename cpu_riscv_init to riscv_cpu_init * rename riscv_set_mode to riscv_cpu_set_mode Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:23 +08:00
riscv_cpu_set_fflags(env, (val & FSR_AEXC) >> FSR_AEXC_SHIFT);
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
/* User Timers and Counters */
static int read_instret(CPURISCVState *env, int csrno, target_ulong *val)
{
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
*val = cpu_get_icount();
} else {
*val = cpu_get_host_ticks();
}
#else
*val = cpu_get_host_ticks();
#endif
return 0;
}
#if defined(TARGET_RISCV32)
static int read_instreth(CPURISCVState *env, int csrno, target_ulong *val)
{
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
*val = cpu_get_icount() >> 32;
} else {
*val = cpu_get_host_ticks() >> 32;
}
#else
*val = cpu_get_host_ticks() >> 32;
#endif
return 0;
}
#endif /* TARGET_RISCV32 */
#if defined(CONFIG_USER_ONLY)
static int read_time(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = cpu_get_host_ticks();
return 0;
}
#if defined(TARGET_RISCV32)
static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = cpu_get_host_ticks() >> 32;
return 0;
}
#endif
#else /* CONFIG_USER_ONLY */
target/riscv: Emulate TIME CSRs for privileged mode Currently, TIME CSRs are emulated only for user-only mode. This patch add TIME CSRs emulation for privileged mode. For privileged mode, the TIME CSRs will return value provided by rdtime callback which is registered by QEMU machine/platform emulation (i.e. CLINT emulation). If rdtime callback is not available then the monitor (i.e. OpenSBI) will trap-n-emulate TIME CSRs in software. We see 25+% performance improvement in hackbench numbers when TIME CSRs are not trap-n-emulated. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-02 21:42:16 +08:00
static int read_time(CPURISCVState *env, int csrno, target_ulong *val)
{
uint64_t delta = riscv_cpu_virt_enabled(env) ? env->htimedelta : 0;
if (!env->rdtime_fn) {
return -1;
}
*val = env->rdtime_fn() + delta;
return 0;
}
#if defined(TARGET_RISCV32)
static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
{
uint64_t delta = riscv_cpu_virt_enabled(env) ? env->htimedelta : 0;
if (!env->rdtime_fn) {
return -1;
}
*val = (env->rdtime_fn() + delta) >> 32;
return 0;
}
#endif
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Machine constants */
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
#define M_MODE_INTERRUPTS (MIP_MSIP | MIP_MTIP | MIP_MEIP)
#define S_MODE_INTERRUPTS (MIP_SSIP | MIP_STIP | MIP_SEIP)
#define VS_MODE_INTERRUPTS (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP)
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
target/riscv: Extend the MIE CSR to support virtulisation Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:17 +08:00
static const target_ulong delegable_ints = S_MODE_INTERRUPTS |
VS_MODE_INTERRUPTS;
static const target_ulong all_ints = M_MODE_INTERRUPTS | S_MODE_INTERRUPTS |
VS_MODE_INTERRUPTS;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static const target_ulong delegable_excps =
(1ULL << (RISCV_EXCP_INST_ADDR_MIS)) |
(1ULL << (RISCV_EXCP_INST_ACCESS_FAULT)) |
(1ULL << (RISCV_EXCP_ILLEGAL_INST)) |
(1ULL << (RISCV_EXCP_BREAKPOINT)) |
(1ULL << (RISCV_EXCP_LOAD_ADDR_MIS)) |
(1ULL << (RISCV_EXCP_LOAD_ACCESS_FAULT)) |
(1ULL << (RISCV_EXCP_STORE_AMO_ADDR_MIS)) |
(1ULL << (RISCV_EXCP_STORE_AMO_ACCESS_FAULT)) |
(1ULL << (RISCV_EXCP_U_ECALL)) |
(1ULL << (RISCV_EXCP_S_ECALL)) |
target/riscv: Add support for the new execption numbers The v0.5 Hypervisor spec add new execption numbers, let's add support for those. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:01:46 +08:00
(1ULL << (RISCV_EXCP_VS_ECALL)) |
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
(1ULL << (RISCV_EXCP_M_ECALL)) |
(1ULL << (RISCV_EXCP_INST_PAGE_FAULT)) |
(1ULL << (RISCV_EXCP_LOAD_PAGE_FAULT)) |
target/riscv: Add support for the new execption numbers The v0.5 Hypervisor spec add new execption numbers, let's add support for those. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:01:46 +08:00
(1ULL << (RISCV_EXCP_STORE_PAGE_FAULT)) |
(1ULL << (RISCV_EXCP_INST_GUEST_PAGE_FAULT)) |
(1ULL << (RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT)) |
(1ULL << (RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT));
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static const target_ulong sstatus_v1_9_mask = SSTATUS_SIE | SSTATUS_SPIE |
SSTATUS_UIE | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS |
SSTATUS_SUM | SSTATUS_SD;
static const target_ulong sstatus_v1_10_mask = SSTATUS_SIE | SSTATUS_SPIE |
SSTATUS_UIE | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS |
SSTATUS_SUM | SSTATUS_MXR | SSTATUS_SD;
target/riscv: More accurate handling of `sip` CSR According to the spec, "All bits besides SSIP, USIP, and UEIP in the sip register are read-only." Further, if an interrupt is not delegated to mode x, then "the corresponding bits in xip [...] should appear to be hardwired to zero. This patch implements both of those requirements. Signed-off-by: Jonathan Behrens <jonathan@fintelia.io> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-08 06:36:46 +08:00
static const target_ulong sip_writable_mask = SIP_SSIP | MIP_USIP | MIP_UEIP;
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
static const target_ulong hip_writable_mask = MIP_VSSIP | MIP_VSTIP | MIP_VSEIP;
target/riscv: Add Hypervisor virtual CSRs accesses Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:07 +08:00
static const target_ulong vsip_writable_mask = MIP_VSSIP;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#if defined(TARGET_RISCV32)
static const char valid_vm_1_09[16] = {
[VM_1_09_MBARE] = 1,
[VM_1_09_SV32] = 1,
};
static const char valid_vm_1_10[16] = {
[VM_1_10_MBARE] = 1,
[VM_1_10_SV32] = 1
};
#elif defined(TARGET_RISCV64)
static const char valid_vm_1_09[16] = {
[VM_1_09_MBARE] = 1,
[VM_1_09_SV39] = 1,
[VM_1_09_SV48] = 1,
};
static const char valid_vm_1_10[16] = {
[VM_1_10_MBARE] = 1,
[VM_1_10_SV39] = 1,
[VM_1_10_SV48] = 1,
[VM_1_10_SV57] = 1
};
#endif /* CONFIG_USER_ONLY */
/* Machine Information Registers */
static int read_zero(CPURISCVState *env, int csrno, target_ulong *val)
{
return *val = 0;
}
static int read_mhartid(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mhartid;
return 0;
}
/* Machine Trap Setup */
static int read_mstatus(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mstatus;
return 0;
}
static int validate_vm(CPURISCVState *env, target_ulong vm)
{
return (env->priv_ver >= PRIV_VERSION_1_10_0) ?
valid_vm_1_10[vm & 0xf] : valid_vm_1_09[vm & 0xf];
}
static int write_mstatus(CPURISCVState *env, int csrno, target_ulong val)
{
target_ulong mstatus = env->mstatus;
target_ulong mask = 0;
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
int dirty;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* flush tlb on mstatus fields that affect VM */
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
if ((val ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP |
MSTATUS_MPRV | MSTATUS_SUM | MSTATUS_VM)) {
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
tlb_flush(env_cpu(env));
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
MSTATUS_MPP | MSTATUS_MXR |
(validate_vm(env, get_field(val, MSTATUS_VM)) ?
MSTATUS_VM : 0);
}
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
target/riscv: Allow setting mstatus virtulisation bits Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Revieweb-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-20 10:27:18 +08:00
if ((val ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP | MSTATUS_MPV |
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
MSTATUS_MPRV | MSTATUS_SUM)) {
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
tlb_flush(env_cpu(env));
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
RISC-V: Implement mstatus.TSR/TW/TVM This adds the necessary minimum to support S-mode virtualization for priv ISA >= v1.10 Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Co-authored-by: Matthew Suozzo <msuozzo@google.com> Co-authored-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:08 +08:00
MSTATUS_MPP | MSTATUS_MXR | MSTATUS_TVM | MSTATUS_TSR |
MSTATUS_TW;
target/riscv: Allow setting mstatus virtulisation bits Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Revieweb-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-20 10:27:18 +08:00
#if defined(TARGET_RISCV64)
/*
* RV32: MPV and MTL are not in mstatus. The current plan is to
* add them to mstatush. For now, we just don't support it.
*/
target/riscv: Fix mstatus dirty mask This is meant to mask off the hypervisor bits, but a typo caused it to mask MPP instead. Fixes: 1f0419cb04 ("target/riscv: Allow setting mstatus virtulisation bits") Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-08-23 23:21:22 +08:00
mask |= MSTATUS_MTL | MSTATUS_MPV;
target/riscv: Allow setting mstatus virtulisation bits Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Revieweb-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-20 10:27:18 +08:00
#endif
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
mstatus = (mstatus & ~mask) | (val & mask);
target/riscv: update mstatus.SD when FS is set dirty remove the check becuase SD bit should summarize FS and XS fields unconditionally. Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-01-15 14:17:33 +08:00
dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) |
target/riscv: Create function to test if FP is enabled Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Christophe de Dinechin <dinechin@redhat.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-07-31 07:35:24 +08:00
((mstatus & MSTATUS_XS) == MSTATUS_XS);
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
mstatus = set_field(mstatus, MSTATUS_SD, dirty);
env->mstatus = mstatus;
return 0;
}
target/riscv: Add support for the 32-bit MSTATUSH CSR Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:03:05 +08:00
#ifdef TARGET_RISCV32
static int read_mstatush(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mstatush;
return 0;
}
static int write_mstatush(CPURISCVState *env, int csrno, target_ulong val)
{
if ((val ^ env->mstatush) & (MSTATUS_MPV)) {
tlb_flush(env_cpu(env));
}
val &= MSTATUS_MPV | MSTATUS_MTL;
env->mstatush = val;
return 0;
}
#endif
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static int read_misa(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->misa;
return 0;
}
RISC-V: Add misa runtime write support This patch adds support for writing misa. misa is validated based on rules in the ISA specification. 'E' is mutually exclusive with all other extensions. 'D' depends on 'F' so 'D' bit is dropped if 'F' is not present. A conservative approach to consistency is taken by flushing the translation cache on misa writes. misa_mask is added to the CPU struct to store the original set of extensions. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:59:00 +08:00
static int write_misa(CPURISCVState *env, int csrno, target_ulong val)
{
if (!riscv_feature(env, RISCV_FEATURE_MISA)) {
/* drop write to misa */
return 0;
}
/* 'I' or 'E' must be present */
if (!(val & (RVI | RVE))) {
/* It is not, drop write to misa */
return 0;
}
/* 'E' excludes all other extensions */
if (val & RVE) {
/* when we support 'E' we can do "val = RVE;" however
* for now we just drop writes if 'E' is present.
*/
return 0;
}
/* Mask extensions that are not supported by this hart */
val &= env->misa_mask;
/* Mask extensions that are not supported by QEMU */
val &= (RVI | RVE | RVM | RVA | RVF | RVD | RVC | RVS | RVU);
/* 'D' depends on 'F', so clear 'D' if 'F' is not present */
if ((val & RVD) && !(val & RVF)) {
val &= ~RVD;
}
/* Suppress 'C' if next instruction is not aligned
* TODO: this should check next_pc
*/
if ((val & RVC) && (GETPC() & ~3) != 0) {
val &= ~RVC;
}
/* misa.MXL writes are not supported by QEMU */
val = (env->misa & MISA_MXL) | (val & ~MISA_MXL);
/* flush translation cache */
if (val != env->misa) {
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
tb_flush(env_cpu(env));
RISC-V: Add misa runtime write support This patch adds support for writing misa. misa is validated based on rules in the ISA specification. 'E' is mutually exclusive with all other extensions. 'D' depends on 'F' so 'D' bit is dropped if 'F' is not present. A conservative approach to consistency is taken by flushing the translation cache on misa writes. misa_mask is added to the CPU struct to store the original set of extensions. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:59:00 +08:00
}
env->misa = val;
return 0;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static int read_medeleg(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->medeleg;
return 0;
}
static int write_medeleg(CPURISCVState *env, int csrno, target_ulong val)
{
env->medeleg = (env->medeleg & ~delegable_excps) | (val & delegable_excps);
return 0;
}
static int read_mideleg(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mideleg;
return 0;
}
static int write_mideleg(CPURISCVState *env, int csrno, target_ulong val)
{
env->mideleg = (env->mideleg & ~delegable_ints) | (val & delegable_ints);
target/riscv: Set VS bits in mideleg for Hyp extension Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:15 +08:00
if (riscv_has_ext(env, RVH)) {
env->mideleg |= VS_MODE_INTERRUPTS;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
static int read_mie(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mie;
return 0;
}
static int write_mie(CPURISCVState *env, int csrno, target_ulong val)
{
env->mie = (env->mie & ~all_ints) | (val & all_ints);
return 0;
}
static int read_mtvec(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mtvec;
return 0;
}
static int write_mtvec(CPURISCVState *env, int csrno, target_ulong val)
{
/* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
RISC-V: Add support for vectored interrupts If vectored interrupts are enabled (bits[1:0] of mtvec/stvec == 1) then use the following logic for trap entry address calculation: pc = mtvec + cause * 4 In addition to adding support for vectored interrupts this patch simplifies the interrupt delivery logic by making sync/async cause decoding and encoding steps distinct. The cause code and the sign bit indicating sync/async is split at the beginning of the function and fixed cause is renamed to cause. The MSB setting for async traps is delayed until setting mcause/scause to allow redundant variables to be eliminated. Some variables are renamed for conciseness and moved so that decls are at the start of the block. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-16 09:21:03 +08:00
if ((val & 3) < 2) {
env->mtvec = val;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
} else {
RISC-V: Add support for vectored interrupts If vectored interrupts are enabled (bits[1:0] of mtvec/stvec == 1) then use the following logic for trap entry address calculation: pc = mtvec + cause * 4 In addition to adding support for vectored interrupts this patch simplifies the interrupt delivery logic by making sync/async cause decoding and encoding steps distinct. The cause code and the sign bit indicating sync/async is split at the beginning of the function and fixed cause is renamed to cause. The MSB setting for async traps is delayed until setting mcause/scause to allow redundant variables to be eliminated. Some variables are renamed for conciseness and moved so that decls are at the start of the block. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-16 09:21:03 +08:00
qemu_log_mask(LOG_UNIMP, "CSR_MTVEC: reserved mode not supported\n");
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
return 0;
}
static int read_mcounteren(CPURISCVState *env, int csrno, target_ulong *val)
{
if (env->priv_ver < PRIV_VERSION_1_10_0) {
return -1;
}
*val = env->mcounteren;
return 0;
}
static int write_mcounteren(CPURISCVState *env, int csrno, target_ulong val)
{
if (env->priv_ver < PRIV_VERSION_1_10_0) {
return -1;
}
env->mcounteren = val;
return 0;
}
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
/* This regiser is replaced with CSR_MCOUNTINHIBIT in 1.11.0 */
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static int read_mscounteren(CPURISCVState *env, int csrno, target_ulong *val)
{
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
if (env->priv_ver > PRIV_VERSION_1_09_1
&& env->priv_ver < PRIV_VERSION_1_11_0) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
*val = env->mcounteren;
return 0;
}
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
/* This regiser is replaced with CSR_MCOUNTINHIBIT in 1.11.0 */
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
static int write_mscounteren(CPURISCVState *env, int csrno, target_ulong val)
{
target/riscv: Add the mcountinhibit CSR 1.11 defines mcountinhibit, which has the same numeric CSR value as mucounteren from 1.09.1 but has different semantics. This patch enables the CSR for 1.11-based targets, which is trivial to implement because the counters in QEMU never tick (legal according to the spec). Signed-off-by: Alistair Francis <alistair.francis@wdc.com> [Palmer: Fix counter access semantics, change commit message to indicate the behavior is fully emulated.] Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-18 09:31:08 +08:00
if (env->priv_ver > PRIV_VERSION_1_09_1
&& env->priv_ver < PRIV_VERSION_1_11_0) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
env->mcounteren = val;
return 0;
}
static int read_mucounteren(CPURISCVState *env, int csrno, target_ulong *val)
{
if (env->priv_ver > PRIV_VERSION_1_09_1) {
return -1;
}
*val = env->scounteren;
return 0;
}
static int write_mucounteren(CPURISCVState *env, int csrno, target_ulong val)
{
if (env->priv_ver > PRIV_VERSION_1_09_1) {
return -1;
}
env->scounteren = val;
return 0;
}
/* Machine Trap Handling */
static int read_mscratch(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mscratch;
return 0;
}
static int write_mscratch(CPURISCVState *env, int csrno, target_ulong val)
{
env->mscratch = val;
return 0;
}
static int read_mepc(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mepc;
return 0;
}
static int write_mepc(CPURISCVState *env, int csrno, target_ulong val)
{
env->mepc = val;
return 0;
}
static int read_mcause(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mcause;
return 0;
}
static int write_mcause(CPURISCVState *env, int csrno, target_ulong val)
{
env->mcause = val;
return 0;
}
static int read_mbadaddr(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mbadaddr;
return 0;
}
static int write_mbadaddr(CPURISCVState *env, int csrno, target_ulong val)
{
env->mbadaddr = val;
return 0;
}
RISC-V: Implement atomic mip/sip CSR updates Use the new CSR read/modify/write interface to implement atomic updates to mip/sip. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:04 +08:00
static int rmw_mip(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
{
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
RISCVCPU *cpu = env_archcpu(env);
RISC-V: Allow interrupt controllers to claim interrupts We can't allow the supervisor to control SEIP as this would allow the supervisor to clear a pending external interrupt which will result in lost a interrupt in the case a PLIC is attached. The SEIP bit must be hardware controlled when a PLIC is attached. This logic was previously hard-coded so SEIP was always masked even if no PLIC was attached. This patch adds riscv_cpu_claim_interrupts so that the PLIC can register control of SEIP. In the case of models without a PLIC (spike), the SEIP bit remains software controlled. This interface allows for hardware control of supervisor timer and software interrupts by other interrupt controller models. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-16 09:20:20 +08:00
/* Allow software control of delegable interrupts not claimed by hardware */
target_ulong mask = write_mask & delegable_ints & ~env->miclaim;
RISC-V: Implement atomic mip/sip CSR updates Use the new CSR read/modify/write interface to implement atomic updates to mip/sip. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:04 +08:00
uint32_t old_mip;
if (mask) {
old_mip = riscv_cpu_update_mip(cpu, mask, (new_value & mask));
} else {
target/riscv: Remove atomic accesses to MIP CSR Instead of relying on atomics to access the MIP register let's update our helper function to instead just lock the IO mutex thread before writing. This follows the same concept as used in PPC for handling interrupts Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Palmer Dabbelt <palmer@dabbelt.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2019-10-09 06:04:18 +08:00
old_mip = env->mip;
RISC-V: Implement atomic mip/sip CSR updates Use the new CSR read/modify/write interface to implement atomic updates to mip/sip. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:04 +08:00
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
RISC-V: Implement atomic mip/sip CSR updates Use the new CSR read/modify/write interface to implement atomic updates to mip/sip. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:04 +08:00
if (ret_value) {
*ret_value = old_mip;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
/* Supervisor Trap Setup */
static int read_sstatus(CPURISCVState *env, int csrno, target_ulong *val)
{
target_ulong mask = ((env->priv_ver >= PRIV_VERSION_1_10_0) ?
sstatus_v1_10_mask : sstatus_v1_9_mask);
*val = env->mstatus & mask;
return 0;
}
static int write_sstatus(CPURISCVState *env, int csrno, target_ulong val)
{
target_ulong mask = ((env->priv_ver >= PRIV_VERSION_1_10_0) ?
sstatus_v1_10_mask : sstatus_v1_9_mask);
target_ulong newval = (env->mstatus & ~mask) | (val & mask);
return write_mstatus(env, CSR_MSTATUS, newval);
}
static int read_sie(CPURISCVState *env, int csrno, target_ulong *val)
{
target/riscv: Extend the MIE CSR to support virtulisation Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:17 +08:00
if (riscv_cpu_virt_enabled(env)) {
/* Tell the guest the VS bits, shifted to the S bit locations */
*val = (env->mie & env->mideleg & VS_MODE_INTERRUPTS) >> 1;
} else {
*val = env->mie & env->mideleg;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return 0;
}
static int write_sie(CPURISCVState *env, int csrno, target_ulong val)
{
target/riscv: Extend the MIE CSR to support virtulisation Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:17 +08:00
target_ulong newval;
if (riscv_cpu_virt_enabled(env)) {
/* Shift the guests S bits to VS */
newval = (env->mie & ~VS_MODE_INTERRUPTS) |
((val << 1) & VS_MODE_INTERRUPTS);
} else {
newval = (env->mie & ~S_MODE_INTERRUPTS) | (val & S_MODE_INTERRUPTS);
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return write_mie(env, CSR_MIE, newval);
}
static int read_stvec(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->stvec;
return 0;
}
static int write_stvec(CPURISCVState *env, int csrno, target_ulong val)
{
/* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
RISC-V: Add support for vectored interrupts If vectored interrupts are enabled (bits[1:0] of mtvec/stvec == 1) then use the following logic for trap entry address calculation: pc = mtvec + cause * 4 In addition to adding support for vectored interrupts this patch simplifies the interrupt delivery logic by making sync/async cause decoding and encoding steps distinct. The cause code and the sign bit indicating sync/async is split at the beginning of the function and fixed cause is renamed to cause. The MSB setting for async traps is delayed until setting mcause/scause to allow redundant variables to be eliminated. Some variables are renamed for conciseness and moved so that decls are at the start of the block. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-16 09:21:03 +08:00
if ((val & 3) < 2) {
env->stvec = val;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
} else {
RISC-V: Add support for vectored interrupts If vectored interrupts are enabled (bits[1:0] of mtvec/stvec == 1) then use the following logic for trap entry address calculation: pc = mtvec + cause * 4 In addition to adding support for vectored interrupts this patch simplifies the interrupt delivery logic by making sync/async cause decoding and encoding steps distinct. The cause code and the sign bit indicating sync/async is split at the beginning of the function and fixed cause is renamed to cause. The MSB setting for async traps is delayed until setting mcause/scause to allow redundant variables to be eliminated. Some variables are renamed for conciseness and moved so that decls are at the start of the block. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-16 09:21:03 +08:00
qemu_log_mask(LOG_UNIMP, "CSR_STVEC: reserved mode not supported\n");
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
return 0;
}
static int read_scounteren(CPURISCVState *env, int csrno, target_ulong *val)
{
if (env->priv_ver < PRIV_VERSION_1_10_0) {
return -1;
}
*val = env->scounteren;
return 0;
}
static int write_scounteren(CPURISCVState *env, int csrno, target_ulong val)
{
if (env->priv_ver < PRIV_VERSION_1_10_0) {
return -1;
}
env->scounteren = val;
return 0;
}
/* Supervisor Trap Handling */
static int read_sscratch(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->sscratch;
return 0;
}
static int write_sscratch(CPURISCVState *env, int csrno, target_ulong val)
{
env->sscratch = val;
return 0;
}
static int read_sepc(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->sepc;
return 0;
}
static int write_sepc(CPURISCVState *env, int csrno, target_ulong val)
{
env->sepc = val;
return 0;
}
static int read_scause(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->scause;
return 0;
}
static int write_scause(CPURISCVState *env, int csrno, target_ulong val)
{
env->scause = val;
return 0;
}
static int read_sbadaddr(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->sbadaddr;
return 0;
}
static int write_sbadaddr(CPURISCVState *env, int csrno, target_ulong val)
{
env->sbadaddr = val;
return 0;
}
RISC-V: Implement atomic mip/sip CSR updates Use the new CSR read/modify/write interface to implement atomic updates to mip/sip. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:04 +08:00
static int rmw_sip(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
{
target/riscv: Extend the SIP CSR to support virtulisation Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:20 +08:00
int ret;
if (riscv_cpu_virt_enabled(env)) {
/* Shift the new values to line up with the VS bits */
ret = rmw_mip(env, CSR_MSTATUS, ret_value, new_value << 1,
(write_mask & sip_writable_mask) << 1 & env->mideleg);
ret &= vsip_writable_mask;
ret >>= 1;
} else {
ret = rmw_mip(env, CSR_MSTATUS, ret_value, new_value,
target/riscv: More accurate handling of `sip` CSR According to the spec, "All bits besides SSIP, USIP, and UEIP in the sip register are read-only." Further, if an interrupt is not delegated to mode x, then "the corresponding bits in xip [...] should appear to be hardwired to zero. This patch implements both of those requirements. Signed-off-by: Jonathan Behrens <jonathan@fintelia.io> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-08 06:36:46 +08:00
write_mask & env->mideleg & sip_writable_mask);
target/riscv: Extend the SIP CSR to support virtulisation Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:20 +08:00
}
target/riscv: More accurate handling of `sip` CSR According to the spec, "All bits besides SSIP, USIP, and UEIP in the sip register are read-only." Further, if an interrupt is not delegated to mode x, then "the corresponding bits in xip [...] should appear to be hardwired to zero. This patch implements both of those requirements. Signed-off-by: Jonathan Behrens <jonathan@fintelia.io> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-08 06:36:46 +08:00
*ret_value &= env->mideleg;
return ret;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
/* Supervisor Protection and Translation */
static int read_satp(CPURISCVState *env, int csrno, target_ulong *val)
{
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
*val = 0;
} else if (env->priv_ver >= PRIV_VERSION_1_10_0) {
RISC-V: Implement mstatus.TSR/TW/TVM This adds the necessary minimum to support S-mode virtualization for priv ISA >= v1.10 Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Co-authored-by: Matthew Suozzo <msuozzo@google.com> Co-authored-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:08 +08:00
if (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_TVM)) {
return -1;
} else {
*val = env->satp;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
} else {
*val = env->sptbr;
}
return 0;
}
static int write_satp(CPURISCVState *env, int csrno, target_ulong val)
{
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
return 0;
}
if (env->priv_ver <= PRIV_VERSION_1_09_1 && (val ^ env->sptbr)) {
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
tlb_flush(env_cpu(env));
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
env->sptbr = val & (((target_ulong)
1 << (TARGET_PHYS_ADDR_SPACE_BITS - PGSHIFT)) - 1);
}
if (env->priv_ver >= PRIV_VERSION_1_10_0 &&
validate_vm(env, get_field(val, SATP_MODE)) &&
((val ^ env->satp) & (SATP_MODE | SATP_ASID | SATP_PPN)))
{
RISC-V: Implement mstatus.TSR/TW/TVM This adds the necessary minimum to support S-mode virtualization for priv ISA >= v1.10 Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Co-authored-by: Matthew Suozzo <msuozzo@google.com> Co-authored-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:08 +08:00
if (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_TVM)) {
return -1;
} else {
target/riscv: Only flush TLB if SATP.ASID changes There is an analogous change for ARM here: https://patchwork.kernel.org/patch/10649857 Signed-off-by: Jonathan Behrens <jonathan@fintelia.io> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-09 01:38:35 +08:00
if((val ^ env->satp) & SATP_ASID) {
target/riscv: Use env_cpu, env_archcpu Cleanup in the boilerplate that each target must define. Replace riscv_env_get_cpu with env_archcpu. The combination CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-03-23 10:11:37 +08:00
tlb_flush(env_cpu(env));
target/riscv: Only flush TLB if SATP.ASID changes There is an analogous change for ARM here: https://patchwork.kernel.org/patch/10649857 Signed-off-by: Jonathan Behrens <jonathan@fintelia.io> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-09 01:38:35 +08:00
}
RISC-V: Implement mstatus.TSR/TW/TVM This adds the necessary minimum to support S-mode virtualization for priv ISA >= v1.10 Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Co-authored-by: Matthew Suozzo <msuozzo@google.com> Co-authored-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:58:08 +08:00
env->satp = val;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
}
return 0;
}
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
/* Hypervisor Extensions */
static int read_hstatus(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->hstatus;
return 0;
}
static int write_hstatus(CPURISCVState *env, int csrno, target_ulong val)
{
env->hstatus = val;
return 0;
}
static int read_hedeleg(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->hedeleg;
return 0;
}
static int write_hedeleg(CPURISCVState *env, int csrno, target_ulong val)
{
env->hedeleg = val;
return 0;
}
static int read_hideleg(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->hideleg;
return 0;
}
static int write_hideleg(CPURISCVState *env, int csrno, target_ulong val)
{
env->hideleg = val;
return 0;
}
static int rmw_hip(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
{
int ret = rmw_mip(env, 0, ret_value, new_value,
write_mask & hip_writable_mask);
return ret;
}
static int read_hie(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mie & VS_MODE_INTERRUPTS;
return 0;
}
static int write_hie(CPURISCVState *env, int csrno, target_ulong val)
{
target_ulong newval = (env->mie & ~VS_MODE_INTERRUPTS) | (val & VS_MODE_INTERRUPTS);
return write_mie(env, CSR_MIE, newval);
}
static int read_hcounteren(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->hcounteren;
return 0;
}
static int write_hcounteren(CPURISCVState *env, int csrno, target_ulong val)
{
env->hcounteren = val;
return 0;
}
static int read_htval(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->htval;
return 0;
}
static int write_htval(CPURISCVState *env, int csrno, target_ulong val)
{
env->htval = val;
return 0;
}
static int read_htinst(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->htinst;
return 0;
}
static int write_htinst(CPURISCVState *env, int csrno, target_ulong val)
{
env->htinst = val;
return 0;
}
static int read_hgatp(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->hgatp;
return 0;
}
static int write_hgatp(CPURISCVState *env, int csrno, target_ulong val)
{
env->hgatp = val;
return 0;
}
target/riscv: Emulate TIME CSRs for privileged mode Currently, TIME CSRs are emulated only for user-only mode. This patch add TIME CSRs emulation for privileged mode. For privileged mode, the TIME CSRs will return value provided by rdtime callback which is registered by QEMU machine/platform emulation (i.e. CLINT emulation). If rdtime callback is not available then the monitor (i.e. OpenSBI) will trap-n-emulate TIME CSRs in software. We see 25+% performance improvement in hackbench numbers when TIME CSRs are not trap-n-emulated. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-02 21:42:16 +08:00
static int read_htimedelta(CPURISCVState *env, int csrno, target_ulong *val)
{
if (!env->rdtime_fn) {
return -1;
}
#if defined(TARGET_RISCV32)
*val = env->htimedelta & 0xffffffff;
#else
*val = env->htimedelta;
#endif
return 0;
}
static int write_htimedelta(CPURISCVState *env, int csrno, target_ulong val)
{
if (!env->rdtime_fn) {
return -1;
}
#if defined(TARGET_RISCV32)
env->htimedelta = deposit64(env->htimedelta, 0, 32, (uint64_t)val);
#else
env->htimedelta = val;
#endif
return 0;
}
#if defined(TARGET_RISCV32)
static int read_htimedeltah(CPURISCVState *env, int csrno, target_ulong *val)
{
if (!env->rdtime_fn) {
return -1;
}
*val = env->htimedelta >> 32;
return 0;
}
static int write_htimedeltah(CPURISCVState *env, int csrno, target_ulong val)
{
if (!env->rdtime_fn) {
return -1;
}
env->htimedelta = deposit64(env->htimedelta, 32, 32, (uint64_t)val);
return 0;
}
#endif
target/riscv: Add Hypervisor virtual CSRs accesses Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:07 +08:00
/* Virtual CSR Registers */
static int read_vsstatus(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vsstatus;
return 0;
}
static int write_vsstatus(CPURISCVState *env, int csrno, target_ulong val)
{
env->vsstatus = val;
return 0;
}
static int rmw_vsip(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
{
int ret = rmw_mip(env, 0, ret_value, new_value,
write_mask & env->mideleg & vsip_writable_mask);
return ret;
}
static int read_vsie(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mie & env->mideleg & VS_MODE_INTERRUPTS;
return 0;
}
static int write_vsie(CPURISCVState *env, int csrno, target_ulong val)
{
target_ulong newval = (env->mie & ~env->mideleg) | (val & env->mideleg & MIP_VSSIP);
return write_mie(env, CSR_MIE, newval);
}
static int read_vstvec(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vstvec;
return 0;
}
static int write_vstvec(CPURISCVState *env, int csrno, target_ulong val)
{
env->vstvec = val;
return 0;
}
static int read_vsscratch(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vsscratch;
return 0;
}
static int write_vsscratch(CPURISCVState *env, int csrno, target_ulong val)
{
env->vsscratch = val;
return 0;
}
static int read_vsepc(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vsepc;
return 0;
}
static int write_vsepc(CPURISCVState *env, int csrno, target_ulong val)
{
env->vsepc = val;
return 0;
}
static int read_vscause(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vscause;
return 0;
}
static int write_vscause(CPURISCVState *env, int csrno, target_ulong val)
{
env->vscause = val;
return 0;
}
static int read_vstval(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vstval;
return 0;
}
static int write_vstval(CPURISCVState *env, int csrno, target_ulong val)
{
env->vstval = val;
return 0;
}
static int read_vsatp(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->vsatp;
return 0;
}
static int write_vsatp(CPURISCVState *env, int csrno, target_ulong val)
{
env->vsatp = val;
return 0;
}
target/riscv: Add Hypervisor machine CSRs accesses Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:10 +08:00
static int read_mtval2(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mtval2;
return 0;
}
static int write_mtval2(CPURISCVState *env, int csrno, target_ulong val)
{
env->mtval2 = val;
return 0;
}
static int read_mtinst(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = env->mtinst;
return 0;
}
static int write_mtinst(CPURISCVState *env, int csrno, target_ulong val)
{
env->mtinst = val;
return 0;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Physical Memory Protection */
static int read_pmpcfg(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = pmpcfg_csr_read(env, csrno - CSR_PMPCFG0);
return 0;
}
static int write_pmpcfg(CPURISCVState *env, int csrno, target_ulong val)
{
pmpcfg_csr_write(env, csrno - CSR_PMPCFG0, val);
return 0;
}
static int read_pmpaddr(CPURISCVState *env, int csrno, target_ulong *val)
{
*val = pmpaddr_csr_read(env, csrno - CSR_PMPADDR0);
return 0;
}
static int write_pmpaddr(CPURISCVState *env, int csrno, target_ulong val)
{
pmpaddr_csr_write(env, csrno - CSR_PMPADDR0, val);
return 0;
}
#endif
/*
* riscv_csrrw - read and/or update control and status register
*
* csrr <-> riscv_csrrw(env, csrno, ret_value, 0, 0);
* csrrw <-> riscv_csrrw(env, csrno, ret_value, value, -1);
* csrrs <-> riscv_csrrw(env, csrno, ret_value, -1, value);
* csrrc <-> riscv_csrrw(env, csrno, ret_value, 0, value);
*/
int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
{
int ret;
target_ulong old_value;
RISC-V: Add support for the Zicsr extension The various CSR instructions have been split out of the base ISA as part of the ratification process. This patch adds a Zicsr argument, which disables all the CSR instructions. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2019-06-24 16:59:51 +08:00
RISCVCPU *cpu = env_archcpu(env);
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* check privileges and return -1 if check fails */
#if !defined(CONFIG_USER_ONLY)
target/riscv: Fix CSR perm checking for HS mode Update the CSR permission checking to work correctly when we are in HS-mode. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:01:56 +08:00
int effective_priv = env->priv;
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
int read_only = get_field(csrno, 0xC00) == 3;
target/riscv: Fix CSR perm checking for HS mode Update the CSR permission checking to work correctly when we are in HS-mode. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:01:56 +08:00
if (riscv_has_ext(env, RVH) &&
env->priv == PRV_S &&
!riscv_cpu_virt_enabled(env)) {
/*
* We are in S mode without virtualisation, therefore we are in HS Mode.
* Add 1 to the effective privledge level to allow us to access the
* Hypervisor CSRs.
*/
effective_priv++;
riscv: Skip checking CSR privilege level in debugger mode If we are in debugger mode, skip the CSR privilege level checking so that we can read/write all CSRs. Otherwise we get: (gdb) p/x $mtvec Could not fetch register "mtvec"; remote failure reply 'E14' when the hart is currently in S-mode. Reported-by: Zong Li <zong.li@sifive.com> Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-09-20 22:47:14 +08:00
}
target/riscv: Fix CSR perm checking for HS mode Update the CSR permission checking to work correctly when we are in HS-mode. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:01:56 +08:00
if ((write_mask && read_only) ||
(!env->debugger && (effective_priv < get_field(csrno, 0x300)))) {
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
return -1;
}
#endif
RISC-V: Add support for the Zicsr extension The various CSR instructions have been split out of the base ISA as part of the ratification process. This patch adds a Zicsr argument, which disables all the CSR instructions. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2019-06-24 16:59:51 +08:00
/* ensure the CSR extension is enabled. */
if (!cpu->cfg.ext_icsr) {
return -1;
}
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
/* check predicate */
if (!csr_ops[csrno].predicate || csr_ops[csrno].predicate(env, csrno) < 0) {
return -1;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* execute combined read/write operation if it exists */
if (csr_ops[csrno].op) {
return csr_ops[csrno].op(env, csrno, ret_value, new_value, write_mask);
}
/* if no accessor exists then return failure */
if (!csr_ops[csrno].read) {
return -1;
}
/* read old value */
ret = csr_ops[csrno].read(env, csrno, &old_value);
if (ret < 0) {
return ret;
}
/* write value if writable and write mask set, otherwise drop writes */
if (write_mask) {
new_value = (old_value & ~write_mask) | (new_value & write_mask);
if (csr_ops[csrno].write) {
ret = csr_ops[csrno].write(env, csrno, new_value);
if (ret < 0) {
return ret;
}
}
}
/* return old value */
if (ret_value) {
*ret_value = old_value;
}
return 0;
}
RISC-V: Add debug support for accessing CSRs. Add a debugger field to CPURISCVState. Add riscv_csrrw_debug function to set it. Disable mode checks when debugger field true. Signed-off-by: Jim Wilson <jimw@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20190212230903.9215-1-jimw@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-15 18:26:58 +08:00
/*
* Debugger support. If not in user mode, set env->debugger before the
* riscv_csrrw call and clear it after the call.
*/
int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
target_ulong new_value, target_ulong write_mask)
{
int ret;
#if !defined(CONFIG_USER_ONLY)
env->debugger = true;
#endif
ret = riscv_csrrw(env, csrno, ret_value, new_value, write_mask);
#if !defined(CONFIG_USER_ONLY)
env->debugger = false;
#endif
return ret;
}
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Control and Status Register function table */
static riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
/* User Floating-Point CSRs */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_FFLAGS] = { fs, read_fflags, write_fflags },
[CSR_FRM] = { fs, read_frm, write_frm },
[CSR_FCSR] = { fs, read_fcsr, write_fcsr },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* User Timers and Counters */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_CYCLE] = { ctr, read_instret },
[CSR_INSTRET] = { ctr, read_instret },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#if defined(TARGET_RISCV32)
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_CYCLEH] = { ctr, read_instreth },
[CSR_INSTRETH] = { ctr, read_instreth },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#endif
target/riscv: Emulate TIME CSRs for privileged mode Currently, TIME CSRs are emulated only for user-only mode. This patch add TIME CSRs emulation for privileged mode. For privileged mode, the TIME CSRs will return value provided by rdtime callback which is registered by QEMU machine/platform emulation (i.e. CLINT emulation). If rdtime callback is not available then the monitor (i.e. OpenSBI) will trap-n-emulate TIME CSRs in software. We see 25+% performance improvement in hackbench numbers when TIME CSRs are not trap-n-emulated. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-02 21:42:16 +08:00
/* In privileged mode, the monitor will have to emulate TIME CSRs only if
* rdtime callback is not provided by machine/platform emulation */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_TIME] = { ctr, read_time },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#if defined(TARGET_RISCV32)
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_TIMEH] = { ctr, read_timeh },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#endif
#if !defined(CONFIG_USER_ONLY)
/* Machine Timers and Counters */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MCYCLE] = { any, read_instret },
[CSR_MINSTRET] = { any, read_instret },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#if defined(TARGET_RISCV32)
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MCYCLEH] = { any, read_instreth },
[CSR_MINSTRETH] = { any, read_instreth },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#endif
/* Machine Information Registers */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MVENDORID] = { any, read_zero },
[CSR_MARCHID] = { any, read_zero },
[CSR_MIMPID] = { any, read_zero },
[CSR_MHARTID] = { any, read_mhartid },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Machine Trap Setup */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MSTATUS] = { any, read_mstatus, write_mstatus },
RISC-V: Add misa runtime write support This patch adds support for writing misa. misa is validated based on rules in the ISA specification. 'E' is mutually exclusive with all other extensions. 'D' depends on 'F' so 'D' bit is dropped if 'F' is not present. A conservative approach to consistency is taken by flushing the translation cache on misa writes. misa_mask is added to the CPU struct to store the original set of extensions. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-15 07:59:00 +08:00
[CSR_MISA] = { any, read_misa, write_misa },
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MIDELEG] = { any, read_mideleg, write_mideleg },
[CSR_MEDELEG] = { any, read_medeleg, write_medeleg },
[CSR_MIE] = { any, read_mie, write_mie },
[CSR_MTVEC] = { any, read_mtvec, write_mtvec },
[CSR_MCOUNTEREN] = { any, read_mcounteren, write_mcounteren },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
target/riscv: Add support for the 32-bit MSTATUSH CSR Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:03:05 +08:00
#if defined(TARGET_RISCV32)
[CSR_MSTATUSH] = { any, read_mstatush, write_mstatush },
#endif
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Legacy Counter Setup (priv v1.9.1) */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MUCOUNTEREN] = { any, read_mucounteren, write_mucounteren },
[CSR_MSCOUNTEREN] = { any, read_mscounteren, write_mscounteren },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Machine Trap Handling */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_MSCRATCH] = { any, read_mscratch, write_mscratch },
[CSR_MEPC] = { any, read_mepc, write_mepc },
[CSR_MCAUSE] = { any, read_mcause, write_mcause },
[CSR_MBADADDR] = { any, read_mbadaddr, write_mbadaddr },
[CSR_MIP] = { any, NULL, NULL, rmw_mip },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Supervisor Trap Setup */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_SSTATUS] = { smode, read_sstatus, write_sstatus },
[CSR_SIE] = { smode, read_sie, write_sie },
[CSR_STVEC] = { smode, read_stvec, write_stvec },
[CSR_SCOUNTEREN] = { smode, read_scounteren, write_scounteren },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Supervisor Trap Handling */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_SSCRATCH] = { smode, read_sscratch, write_sscratch },
[CSR_SEPC] = { smode, read_sepc, write_sepc },
[CSR_SCAUSE] = { smode, read_scause, write_scause },
[CSR_SBADADDR] = { smode, read_sbadaddr, write_sbadaddr },
[CSR_SIP] = { smode, NULL, NULL, rmw_sip },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Supervisor Protection and Translation */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_SATP] = { smode, read_satp, write_satp },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
[CSR_HSTATUS] = { hmode, read_hstatus, write_hstatus },
[CSR_HEDELEG] = { hmode, read_hedeleg, write_hedeleg },
[CSR_HIDELEG] = { hmode, read_hideleg, write_hideleg },
[CSR_HIP] = { hmode, NULL, NULL, rmw_hip },
[CSR_HIE] = { hmode, read_hie, write_hie },
[CSR_HCOUNTEREN] = { hmode, read_hcounteren, write_hcounteren },
[CSR_HTVAL] = { hmode, read_htval, write_htval },
[CSR_HTINST] = { hmode, read_htinst, write_htinst },
[CSR_HGATP] = { hmode, read_hgatp, write_hgatp },
target/riscv: Emulate TIME CSRs for privileged mode Currently, TIME CSRs are emulated only for user-only mode. This patch add TIME CSRs emulation for privileged mode. For privileged mode, the TIME CSRs will return value provided by rdtime callback which is registered by QEMU machine/platform emulation (i.e. CLINT emulation). If rdtime callback is not available then the monitor (i.e. OpenSBI) will trap-n-emulate TIME CSRs in software. We see 25+% performance improvement in hackbench numbers when TIME CSRs are not trap-n-emulated. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-02 21:42:16 +08:00
[CSR_HTIMEDELTA] = { hmode, read_htimedelta, write_htimedelta },
#if defined(TARGET_RISCV32)
[CSR_HTIMEDELTAH] = { hmode, read_htimedeltah, write_htimedeltah},
#endif
target/riscv: Add Hypervisor CSR access functions Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:04 +08:00
target/riscv: Add Hypervisor virtual CSRs accesses Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:07 +08:00
[CSR_VSSTATUS] = { hmode, read_vsstatus, write_vsstatus },
[CSR_VSIP] = { hmode, NULL, NULL, rmw_vsip },
[CSR_VSIE] = { hmode, read_vsie, write_vsie },
[CSR_VSTVEC] = { hmode, read_vstvec, write_vstvec },
[CSR_VSSCRATCH] = { hmode, read_vsscratch, write_vsscratch },
[CSR_VSEPC] = { hmode, read_vsepc, write_vsepc },
[CSR_VSCAUSE] = { hmode, read_vscause, write_vscause },
[CSR_VSTVAL] = { hmode, read_vstval, write_vstval },
[CSR_VSATP] = { hmode, read_vsatp, write_vsatp },
target/riscv: Add Hypervisor machine CSRs accesses Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-01 09:02:10 +08:00
[CSR_MTVAL2] = { hmode, read_mtval2, write_mtval2 },
[CSR_MTINST] = { hmode, read_mtinst, write_mtinst },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Physical Memory Protection */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_PMPCFG0 ... CSR_PMPADDR9] = { pmp, read_pmpcfg, write_pmpcfg },
[CSR_PMPADDR0 ... CSR_PMPADDR15] = { pmp, read_pmpaddr, write_pmpaddr },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
/* Performance Counters */
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_HPMCOUNTER3 ... CSR_HPMCOUNTER31] = { ctr, read_zero },
[CSR_MHPMCOUNTER3 ... CSR_MHPMCOUNTER31] = { any, read_zero },
[CSR_MHPMEVENT3 ... CSR_MHPMEVENT31] = { any, read_zero },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#if defined(TARGET_RISCV32)
RISC-V: Implement existential predicates for CSRs CSR predicate functions are added to the CSR table. mstatus.FS and counter enable checks are moved to predicate functions and two new predicates are added to check misa.S for s* CSRs and a new PMP CPU feature for pmp* CSRs. Processors that don't implement S-mode will trap on access to s* CSRs and processors that don't implement PMP will trap on accesses to pmp* CSRs. PMP checks are disabled in riscv_cpu_handle_mmu_fault when the PMP CPU feature is not present. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:24:14 +08:00
[CSR_HPMCOUNTER3H ... CSR_HPMCOUNTER31H] = { ctr, read_zero },
[CSR_MHPMCOUNTER3H ... CSR_MHPMCOUNTER31H] = { any, read_zero },
RISC-V: Implement modular CSR helper interface Previous CSR code uses csr_read_helper and csr_write_helper to update CSR registers however this interface prevents atomic read/modify/write CSR operations; in addition there is no trap-free method to access to CSRs due to the monolithic CSR functions call longjmp. The current iCSR interface is not safe to be called by target/riscv/gdbstub.c as privilege checks or missing CSRs may call longjmp to generate exceptions. It needs to indicate existence so traps can be generated in the CSR instruction helpers. This commit moves CSR access from the monolithic switch statements in target/riscv/op_helper.c into modular read/write functions in target/riscv/csr.c using a new function pointer table for dispatch (which can later be used to allow CPUs to hook up model specific CSRs). A read/modify/write interface is added to support atomic CSR operations and a non-trapping interface is added to allow exception-free access to CSRs by the debugger. The CSR functions and CSR dispatch table are ordered to match The RISC-V Instruction Set Manual, Volume II: Privileged Architecture Version 1.10, 2.2 CSR Listing. An API is added to allow derived cpu instances to modify or implement new CSR operations. Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-05 07:23:55 +08:00
#endif
#endif /* !CONFIG_USER_ONLY */
};
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