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qemu/target/riscv/op_helper.c
Michael Clark b8643bd608
RISC-V: No traps on writes to misa,minstret,mcycle 
These fields are marked WARL (Write Any Values, Reads
Legal Values) in the RISC-V Privileged Architecture
Specification so instead of raising exceptions,
illegal writes are silently dropped.

Cc: Sagar Karandikar <sagark@eecs.berkeley.edu>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
2018-05-06 10:39:38 +12:00

750 lines
22 KiB
C
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/*
* RISC-V Emulation Helpers for QEMU.
*
* 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"
#include "exec/helper-proto.h"
#ifndef CONFIG_USER_ONLY
#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
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];
}
#endif
/* Exceptions processing helpers */
void QEMU_NORETURN do_raise_exception_err(CPURISCVState *env,
uint32_t exception, uintptr_t pc)
{
CPUState *cs = CPU(riscv_env_get_cpu(env));
qemu_log_mask(CPU_LOG_INT, "%s: %d\n", __func__, exception);
cs->exception_index = exception;
cpu_loop_exit_restore(cs, pc);
}
void helper_raise_exception(CPURISCVState *env, uint32_t exception)
{
do_raise_exception_err(env, exception, 0);
}
static void validate_mstatus_fs(CPURISCVState *env, uintptr_t ra)
{
#ifndef CONFIG_USER_ONLY
if (!(env->mstatus & MSTATUS_FS)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, ra);
}
#endif
}
/*
* Handle writes to CSRs and any resulting special behavior
*
* Adapted from Spike's processor_t::set_csr
*/
void csr_write_helper(CPURISCVState *env, target_ulong val_to_write,
target_ulong csrno)
{
#ifndef CONFIG_USER_ONLY
uint64_t delegable_ints = MIP_SSIP | MIP_STIP | MIP_SEIP | (1 << IRQ_X_COP);
uint64_t all_ints = delegable_ints | MIP_MSIP | MIP_MTIP;
#endif
switch (csrno) {
case CSR_FFLAGS:
validate_mstatus_fs(env, GETPC());
cpu_riscv_set_fflags(env, val_to_write & (FSR_AEXC >> FSR_AEXC_SHIFT));
break;
case CSR_FRM:
validate_mstatus_fs(env, GETPC());
env->frm = val_to_write & (FSR_RD >> FSR_RD_SHIFT);
break;
case CSR_FCSR:
validate_mstatus_fs(env, GETPC());
env->frm = (val_to_write & FSR_RD) >> FSR_RD_SHIFT;
cpu_riscv_set_fflags(env, (val_to_write & FSR_AEXC) >> FSR_AEXC_SHIFT);
break;
#ifndef CONFIG_USER_ONLY
case CSR_MSTATUS: {
target_ulong mstatus = env->mstatus;
target_ulong mask = 0;
target_ulong mpp = get_field(val_to_write, MSTATUS_MPP);
/* flush tlb on mstatus fields that affect VM */
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
if ((val_to_write ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP |
MSTATUS_MPRV | MSTATUS_SUM | MSTATUS_VM)) {
helper_tlb_flush(env);
}
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_to_write, MSTATUS_VM)) ?
MSTATUS_VM : 0);
}
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
if ((val_to_write ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP |
MSTATUS_MPRV | MSTATUS_SUM)) {
helper_tlb_flush(env);
}
mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
MSTATUS_MPP | MSTATUS_MXR;
}
/* silenty discard mstatus.mpp writes for unsupported modes */
if (mpp == PRV_H ||
(!riscv_has_ext(env, RVS) && mpp == PRV_S) ||
(!riscv_has_ext(env, RVU) && mpp == PRV_U)) {
mask &= ~MSTATUS_MPP;
}
mstatus = (mstatus & ~mask) | (val_to_write & mask);
/* Note: this is a workaround for an issue where mstatus.FS
does not report dirty after floating point operations
that modify floating point state. This workaround is
technically compliant with the RISC-V Privileged
specification as it is legal to return only off, or dirty.
at the expense of extra floating point save/restore. */
/* FP is always dirty or off */
if (mstatus & MSTATUS_FS) {
mstatus |= MSTATUS_FS;
}
int dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) |
((mstatus & MSTATUS_XS) == MSTATUS_XS);
mstatus = set_field(mstatus, MSTATUS_SD, dirty);
env->mstatus = mstatus;
break;
}
case CSR_MIP: {
/*
* Since the writeable bits in MIP are not set asynchrously by the
* CLINT, no additional locking is needed for read-modifiy-write
* CSR operations
*/
qemu_mutex_lock_iothread();
RISCVCPU *cpu = riscv_env_get_cpu(env);
riscv_set_local_interrupt(cpu, MIP_SSIP,
(val_to_write & MIP_SSIP) != 0);
riscv_set_local_interrupt(cpu, MIP_STIP,
(val_to_write & MIP_STIP) != 0);
/*
* csrs, csrc on mip.SEIP is not decomposable into separate read and
* write steps, so a different implementation is needed
*/
qemu_mutex_unlock_iothread();
break;
}
case CSR_MIE: {
env->mie = (env->mie & ~all_ints) |
(val_to_write & all_ints);
break;
}
case CSR_MIDELEG:
env->mideleg = (env->mideleg & ~delegable_ints)
| (val_to_write & delegable_ints);
break;
case CSR_MEDELEG: {
target_ulong mask = 0;
mask |= 1ULL << (RISCV_EXCP_INST_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_INST_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_ILLEGAL_INST);
mask |= 1ULL << (RISCV_EXCP_BREAKPOINT);
mask |= 1ULL << (RISCV_EXCP_LOAD_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_LOAD_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_STORE_AMO_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_STORE_AMO_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_U_ECALL);
mask |= 1ULL << (RISCV_EXCP_S_ECALL);
mask |= 1ULL << (RISCV_EXCP_H_ECALL);
mask |= 1ULL << (RISCV_EXCP_M_ECALL);
mask |= 1ULL << (RISCV_EXCP_INST_PAGE_FAULT);
mask |= 1ULL << (RISCV_EXCP_LOAD_PAGE_FAULT);
mask |= 1ULL << (RISCV_EXCP_STORE_PAGE_FAULT);
env->medeleg = (env->medeleg & ~mask)
| (val_to_write & mask);
break;
}
case CSR_MINSTRET:
/* minstret is WARL so unsupported writes are ignored */
break;
case CSR_MCYCLE:
/* mcycle is WARL so unsupported writes are ignored */
break;
#if defined(TARGET_RISCV32)
case CSR_MINSTRETH:
/* minstreth is WARL so unsupported writes are ignored */
break;
case CSR_MCYCLEH:
/* mcycleh is WARL so unsupported writes are ignored */
break;
#endif
case CSR_MUCOUNTEREN:
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
env->scounteren = val_to_write;
break;
} else {
goto do_illegal;
}
case CSR_MSCOUNTEREN:
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
env->mcounteren = val_to_write;
break;
} else {
goto do_illegal;
}
case CSR_SSTATUS: {
target_ulong ms = env->mstatus;
target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
| SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
| SSTATUS_SUM | SSTATUS_SD;
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
mask |= SSTATUS_MXR;
}
ms = (ms & ~mask) | (val_to_write & mask);
csr_write_helper(env, ms, CSR_MSTATUS);
break;
}
case CSR_SIP: {
qemu_mutex_lock_iothread();
target_ulong next_mip = (env->mip & ~env->mideleg)
| (val_to_write & env->mideleg);
qemu_mutex_unlock_iothread();
csr_write_helper(env, next_mip, CSR_MIP);
break;
}
case CSR_SIE: {
target_ulong next_mie = (env->mie & ~env->mideleg)
| (val_to_write & env->mideleg);
csr_write_helper(env, next_mie, CSR_MIE);
break;
}
case CSR_SATP: /* CSR_SPTBR */ {
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
break;
}
if (env->priv_ver <= PRIV_VERSION_1_09_1 && (val_to_write ^ env->sptbr))
{
helper_tlb_flush(env);
env->sptbr = val_to_write & (((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_to_write, SATP_MODE)) &&
((val_to_write ^ env->satp) & (SATP_MODE | SATP_ASID | SATP_PPN)))
{
helper_tlb_flush(env);
env->satp = val_to_write;
}
break;
}
case CSR_SEPC:
env->sepc = val_to_write;
break;
case CSR_STVEC:
/* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
if ((val_to_write & 3) == 0) {
env->stvec = val_to_write >> 2 << 2;
} else {
qemu_log_mask(LOG_UNIMP, "CSR_STVEC: vectored traps not supported");
}
break;
case CSR_SCOUNTEREN:
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
env->scounteren = val_to_write;
break;
} else {
goto do_illegal;
}
case CSR_SSCRATCH:
env->sscratch = val_to_write;
break;
case CSR_SCAUSE:
env->scause = val_to_write;
break;
case CSR_SBADADDR:
env->sbadaddr = val_to_write;
break;
case CSR_MEPC:
env->mepc = val_to_write;
break;
case CSR_MTVEC:
/* bits [1:0] indicate mode; 0 = direct, 1 = vectored, 2 >= reserved */
if ((val_to_write & 3) == 0) {
env->mtvec = val_to_write >> 2 << 2;
} else {
qemu_log_mask(LOG_UNIMP, "CSR_MTVEC: vectored traps not supported");
}
break;
case CSR_MCOUNTEREN:
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
env->mcounteren = val_to_write;
break;
} else {
goto do_illegal;
}
case CSR_MSCRATCH:
env->mscratch = val_to_write;
break;
case CSR_MCAUSE:
env->mcause = val_to_write;
break;
case CSR_MBADADDR:
env->mbadaddr = val_to_write;
break;
case CSR_MISA:
/* misa is WARL so unsupported writes are ignored */
break;
case CSR_PMPCFG0:
case CSR_PMPCFG1:
case CSR_PMPCFG2:
case CSR_PMPCFG3:
pmpcfg_csr_write(env, csrno - CSR_PMPCFG0, val_to_write);
break;
case CSR_PMPADDR0:
case CSR_PMPADDR1:
case CSR_PMPADDR2:
case CSR_PMPADDR3:
case CSR_PMPADDR4:
case CSR_PMPADDR5:
case CSR_PMPADDR6:
case CSR_PMPADDR7:
case CSR_PMPADDR8:
case CSR_PMPADDR9:
case CSR_PMPADDR10:
case CSR_PMPADDR11:
case CSR_PMPADDR12:
case CSR_PMPADDR13:
case CSR_PMPADDR14:
case CSR_PMPADDR15:
pmpaddr_csr_write(env, csrno - CSR_PMPADDR0, val_to_write);
break;
#endif
#if !defined(CONFIG_USER_ONLY)
do_illegal:
#endif
default:
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
}
/*
* Handle reads to CSRs and any resulting special behavior
*
* Adapted from Spike's processor_t::get_csr
*/
target_ulong csr_read_helper(CPURISCVState *env, target_ulong csrno)
{
#ifndef CONFIG_USER_ONLY
target_ulong ctr_en = env->priv == PRV_U ? env->scounteren :
env->priv == PRV_S ? env->mcounteren : -1U;
#else
target_ulong ctr_en = -1;
#endif
target_ulong ctr_ok = (ctr_en >> (csrno & 31)) & 1;
if (csrno >= CSR_HPMCOUNTER3 && csrno <= CSR_HPMCOUNTER31) {
if (ctr_ok) {
return 0;
}
}
#if defined(TARGET_RISCV32)
if (csrno >= CSR_HPMCOUNTER3H && csrno <= CSR_HPMCOUNTER31H) {
if (ctr_ok) {
return 0;
}
}
#endif
if (csrno >= CSR_MHPMCOUNTER3 && csrno <= CSR_MHPMCOUNTER31) {
return 0;
}
#if defined(TARGET_RISCV32)
if (csrno >= CSR_MHPMCOUNTER3 && csrno <= CSR_MHPMCOUNTER31) {
return 0;
}
#endif
if (csrno >= CSR_MHPMEVENT3 && csrno <= CSR_MHPMEVENT31) {
return 0;
}
switch (csrno) {
case CSR_FFLAGS:
validate_mstatus_fs(env, GETPC());
return cpu_riscv_get_fflags(env);
case CSR_FRM:
validate_mstatus_fs(env, GETPC());
return env->frm;
case CSR_FCSR:
validate_mstatus_fs(env, GETPC());
return (cpu_riscv_get_fflags(env) << FSR_AEXC_SHIFT)
| (env->frm << FSR_RD_SHIFT);
/* rdtime/rdtimeh is trapped and emulated by bbl in system mode */
#ifdef CONFIG_USER_ONLY
case CSR_TIME:
return cpu_get_host_ticks();
#if defined(TARGET_RISCV32)
case CSR_TIMEH:
return cpu_get_host_ticks() >> 32;
#endif
#endif
case CSR_INSTRET:
case CSR_CYCLE:
if (ctr_ok) {
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
return cpu_get_icount();
} else {
return cpu_get_host_ticks();
}
#else
return cpu_get_host_ticks();
#endif
}
break;
#if defined(TARGET_RISCV32)
case CSR_INSTRETH:
case CSR_CYCLEH:
if (ctr_ok) {
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
return cpu_get_icount() >> 32;
} else {
return cpu_get_host_ticks() >> 32;
}
#else
return cpu_get_host_ticks() >> 32;
#endif
}
break;
#endif
#ifndef CONFIG_USER_ONLY
case CSR_MINSTRET:
case CSR_MCYCLE:
if (use_icount) {
return cpu_get_icount();
} else {
return cpu_get_host_ticks();
}
case CSR_MINSTRETH:
case CSR_MCYCLEH:
#if defined(TARGET_RISCV32)
if (use_icount) {
return cpu_get_icount() >> 32;
} else {
return cpu_get_host_ticks() >> 32;
}
#endif
break;
case CSR_MUCOUNTEREN:
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
return env->scounteren;
} else {
break; /* illegal instruction */
}
case CSR_MSCOUNTEREN:
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
return env->mcounteren;
} else {
break; /* illegal instruction */
}
case CSR_SSTATUS: {
target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
| SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
| SSTATUS_SUM | SSTATUS_SD;
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
mask |= SSTATUS_MXR;
}
return env->mstatus & mask;
}
case CSR_SIP: {
qemu_mutex_lock_iothread();
target_ulong tmp = env->mip & env->mideleg;
qemu_mutex_unlock_iothread();
return tmp;
}
case CSR_SIE:
return env->mie & env->mideleg;
case CSR_SEPC:
return env->sepc;
case CSR_SBADADDR:
return env->sbadaddr;
case CSR_STVEC:
return env->stvec;
case CSR_SCOUNTEREN:
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->scounteren;
} else {
break; /* illegal instruction */
}
case CSR_SCAUSE:
return env->scause;
case CSR_SATP: /* CSR_SPTBR */
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
return 0;
}
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->satp;
} else {
return env->sptbr;
}
case CSR_SSCRATCH:
return env->sscratch;
case CSR_MSTATUS:
return env->mstatus;
case CSR_MIP: {
qemu_mutex_lock_iothread();
target_ulong tmp = env->mip;
qemu_mutex_unlock_iothread();
return tmp;
}
case CSR_MIE:
return env->mie;
case CSR_MEPC:
return env->mepc;
case CSR_MSCRATCH:
return env->mscratch;
case CSR_MCAUSE:
return env->mcause;
case CSR_MBADADDR:
return env->mbadaddr;
case CSR_MISA:
return env->misa;
case CSR_MARCHID:
return 0; /* as spike does */
case CSR_MIMPID:
return 0; /* as spike does */
case CSR_MVENDORID:
return 0; /* as spike does */
case CSR_MHARTID:
return env->mhartid;
case CSR_MTVEC:
return env->mtvec;
case CSR_MCOUNTEREN:
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->mcounteren;
} else {
break; /* illegal instruction */
}
case CSR_MEDELEG:
return env->medeleg;
case CSR_MIDELEG:
return env->mideleg;
case CSR_PMPCFG0:
case CSR_PMPCFG1:
case CSR_PMPCFG2:
case CSR_PMPCFG3:
return pmpcfg_csr_read(env, csrno - CSR_PMPCFG0);
case CSR_PMPADDR0:
case CSR_PMPADDR1:
case CSR_PMPADDR2:
case CSR_PMPADDR3:
case CSR_PMPADDR4:
case CSR_PMPADDR5:
case CSR_PMPADDR6:
case CSR_PMPADDR7:
case CSR_PMPADDR8:
case CSR_PMPADDR9:
case CSR_PMPADDR10:
case CSR_PMPADDR11:
case CSR_PMPADDR12:
case CSR_PMPADDR13:
case CSR_PMPADDR14:
case CSR_PMPADDR15:
return pmpaddr_csr_read(env, csrno - CSR_PMPADDR0);
#endif
}
/* used by e.g. MTIME read */
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
/*
* Check that CSR access is allowed.
*
* Adapted from Spike's decode.h:validate_csr
*/
static void validate_csr(CPURISCVState *env, uint64_t which,
uint64_t write, uintptr_t ra)
{
#ifndef CONFIG_USER_ONLY
unsigned csr_priv = get_field((which), 0x300);
unsigned csr_read_only = get_field((which), 0xC00) == 3;
if (((write) && csr_read_only) || (env->priv < csr_priv)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, ra);
}
#endif
}
target_ulong helper_csrrw(CPURISCVState *env, target_ulong src,
target_ulong csr)
{
validate_csr(env, csr, 1, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
csr_write_helper(env, src, csr);
return csr_backup;
}
target_ulong helper_csrrs(CPURISCVState *env, target_ulong src,
target_ulong csr, target_ulong rs1_pass)
{
validate_csr(env, csr, rs1_pass != 0, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
if (rs1_pass != 0) {
csr_write_helper(env, src | csr_backup, csr);
}
return csr_backup;
}
target_ulong helper_csrrc(CPURISCVState *env, target_ulong src,
target_ulong csr, target_ulong rs1_pass)
{
validate_csr(env, csr, rs1_pass != 0, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
if (rs1_pass != 0) {
csr_write_helper(env, (~src) & csr_backup, csr);
}
return csr_backup;
}
#ifndef CONFIG_USER_ONLY
/* iothread_mutex must be held */
void riscv_set_local_interrupt(RISCVCPU *cpu, target_ulong mask, int value)
{
target_ulong old_mip = cpu->env.mip;
cpu->env.mip = (old_mip & ~mask) | (value ? mask : 0);
if (cpu->env.mip && !old_mip) {
cpu_interrupt(CPU(cpu), CPU_INTERRUPT_HARD);
} else if (!cpu->env.mip && old_mip) {
cpu_reset_interrupt(CPU(cpu), CPU_INTERRUPT_HARD);
}
}
void riscv_set_mode(CPURISCVState *env, target_ulong newpriv)
{
if (newpriv > PRV_M) {
g_assert_not_reached();
}
if (newpriv == PRV_H) {
newpriv = PRV_U;
}
/* tlb_flush is unnecessary as mode is contained in mmu_idx */
env->priv = newpriv;
}
target_ulong helper_sret(CPURISCVState *env, target_ulong cpu_pc_deb)
{
if (!(env->priv >= PRV_S)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
target_ulong retpc = env->sepc;
if (!riscv_has_ext(env, RVC) && (retpc & 0x3)) {
do_raise_exception_err(env, RISCV_EXCP_INST_ADDR_MIS, GETPC());
}
target_ulong mstatus = env->mstatus;
target_ulong prev_priv = get_field(mstatus, MSTATUS_SPP);
mstatus = set_field(mstatus,
env->priv_ver >= PRIV_VERSION_1_10_0 ?
MSTATUS_SIE : MSTATUS_UIE << prev_priv,
get_field(mstatus, MSTATUS_SPIE));
mstatus = set_field(mstatus, MSTATUS_SPIE, 0);
mstatus = set_field(mstatus, MSTATUS_SPP, PRV_U);
riscv_set_mode(env, prev_priv);
csr_write_helper(env, mstatus, CSR_MSTATUS);
return retpc;
}
target_ulong helper_mret(CPURISCVState *env, target_ulong cpu_pc_deb)
{
if (!(env->priv >= PRV_M)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
target_ulong retpc = env->mepc;
if (!riscv_has_ext(env, RVC) && (retpc & 0x3)) {
do_raise_exception_err(env, RISCV_EXCP_INST_ADDR_MIS, GETPC());
}
target_ulong mstatus = env->mstatus;
target_ulong prev_priv = get_field(mstatus, MSTATUS_MPP);
mstatus = set_field(mstatus,
env->priv_ver >= PRIV_VERSION_1_10_0 ?
MSTATUS_MIE : MSTATUS_UIE << prev_priv,
get_field(mstatus, MSTATUS_MPIE));
mstatus = set_field(mstatus, MSTATUS_MPIE, 0);
mstatus = set_field(mstatus, MSTATUS_MPP, PRV_U);
riscv_set_mode(env, prev_priv);
csr_write_helper(env, mstatus, CSR_MSTATUS);
return retpc;
}
void helper_wfi(CPURISCVState *env)
{
CPUState *cs = CPU(riscv_env_get_cpu(env));
cs->halted = 1;
cs->exception_index = EXCP_HLT;
cpu_loop_exit(cs);
}
void helper_tlb_flush(CPURISCVState *env)
{
RISCVCPU *cpu = riscv_env_get_cpu(env);
CPUState *cs = CPU(cpu);
tlb_flush(cs);
}
#endif /* !CONFIG_USER_ONLY */
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