linux/arch/riscv/kernel/sbi.c
Atish Patra 4bb875632a
RISC-V: Add a non-void return for sbi v02 functions
SBI v0.2 functions can return an error code from SBI implementation.
We are already processing the SBI error code and coverts it to the Linux
error code.

Propagate to the error code to the caller as well. As of now, kvm is the
only user of these error codes.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-22 17:51:03 -08:00

604 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* SBI initialilization and all extension implementation.
*
* Copyright (c) 2020 Western Digital Corporation or its affiliates.
*/
#include <linux/init.h>
#include <linux/pm.h>
#include <asm/sbi.h>
#include <asm/smp.h>
/* default SBI version is 0.1 */
unsigned long sbi_spec_version = SBI_SPEC_VERSION_DEFAULT;
EXPORT_SYMBOL(sbi_spec_version);
static void (*__sbi_set_timer)(uint64_t stime);
static int (*__sbi_send_ipi)(const unsigned long *hart_mask);
static int (*__sbi_rfence)(int fid, const unsigned long *hart_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5);
struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
unsigned long arg1, unsigned long arg2,
unsigned long arg3, unsigned long arg4,
unsigned long arg5)
{
struct sbiret ret;
register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);
register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);
register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);
register uintptr_t a3 asm ("a3") = (uintptr_t)(arg3);
register uintptr_t a4 asm ("a4") = (uintptr_t)(arg4);
register uintptr_t a5 asm ("a5") = (uintptr_t)(arg5);
register uintptr_t a6 asm ("a6") = (uintptr_t)(fid);
register uintptr_t a7 asm ("a7") = (uintptr_t)(ext);
asm volatile ("ecall"
: "+r" (a0), "+r" (a1)
: "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7)
: "memory");
ret.error = a0;
ret.value = a1;
return ret;
}
EXPORT_SYMBOL(sbi_ecall);
int sbi_err_map_linux_errno(int err)
{
switch (err) {
case SBI_SUCCESS:
return 0;
case SBI_ERR_DENIED:
return -EPERM;
case SBI_ERR_INVALID_PARAM:
return -EINVAL;
case SBI_ERR_INVALID_ADDRESS:
return -EFAULT;
case SBI_ERR_NOT_SUPPORTED:
case SBI_ERR_FAILURE:
default:
return -ENOTSUPP;
};
}
EXPORT_SYMBOL(sbi_err_map_linux_errno);
#ifdef CONFIG_RISCV_SBI_V01
/**
* sbi_console_putchar() - Writes given character to the console device.
* @ch: The data to be written to the console.
*
* Return: None
*/
void sbi_console_putchar(int ch)
{
sbi_ecall(SBI_EXT_0_1_CONSOLE_PUTCHAR, 0, ch, 0, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_console_putchar);
/**
* sbi_console_getchar() - Reads a byte from console device.
*
* Returns the value read from console.
*/
int sbi_console_getchar(void)
{
struct sbiret ret;
ret = sbi_ecall(SBI_EXT_0_1_CONSOLE_GETCHAR, 0, 0, 0, 0, 0, 0, 0);
return ret.error;
}
EXPORT_SYMBOL(sbi_console_getchar);
/**
* sbi_shutdown() - Remove all the harts from executing supervisor code.
*
* Return: None
*/
void sbi_shutdown(void)
{
sbi_ecall(SBI_EXT_0_1_SHUTDOWN, 0, 0, 0, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_shutdown);
/**
* sbi_clear_ipi() - Clear any pending IPIs for the calling hart.
*
* Return: None
*/
void sbi_clear_ipi(void)
{
sbi_ecall(SBI_EXT_0_1_CLEAR_IPI, 0, 0, 0, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_clear_ipi);
/**
* sbi_set_timer_v01() - Program the timer for next timer event.
* @stime_value: The value after which next timer event should fire.
*
* Return: None
*/
static void __sbi_set_timer_v01(uint64_t stime_value)
{
#if __riscv_xlen == 32
sbi_ecall(SBI_EXT_0_1_SET_TIMER, 0, stime_value,
stime_value >> 32, 0, 0, 0, 0);
#else
sbi_ecall(SBI_EXT_0_1_SET_TIMER, 0, stime_value, 0, 0, 0, 0, 0);
#endif
}
static int __sbi_send_ipi_v01(const unsigned long *hart_mask)
{
sbi_ecall(SBI_EXT_0_1_SEND_IPI, 0, (unsigned long)hart_mask,
0, 0, 0, 0, 0);
return 0;
}
static int __sbi_rfence_v01(int fid, const unsigned long *hart_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5)
{
int result = 0;
/* v0.2 function IDs are equivalent to v0.1 extension IDs */
switch (fid) {
case SBI_EXT_RFENCE_REMOTE_FENCE_I:
sbi_ecall(SBI_EXT_0_1_REMOTE_FENCE_I, 0,
(unsigned long)hart_mask, 0, 0, 0, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA:
sbi_ecall(SBI_EXT_0_1_REMOTE_SFENCE_VMA, 0,
(unsigned long)hart_mask, start, size,
0, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID:
sbi_ecall(SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID, 0,
(unsigned long)hart_mask, start, size,
arg4, 0, 0);
break;
default:
pr_err("SBI call [%d]not supported in SBI v0.1\n", fid);
result = -EINVAL;
}
return result;
}
static void sbi_set_power_off(void)
{
pm_power_off = sbi_shutdown;
}
#else
static void __sbi_set_timer_v01(uint64_t stime_value)
{
pr_warn("Timer extension is not available in SBI v%lu.%lu\n",
sbi_major_version(), sbi_minor_version());
}
static int __sbi_send_ipi_v01(const unsigned long *hart_mask)
{
pr_warn("IPI extension is not available in SBI v%lu.%lu\n",
sbi_major_version(), sbi_minor_version());
return 0;
}
static int __sbi_rfence_v01(int fid, const unsigned long *hart_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5)
{
pr_warn("remote fence extension is not available in SBI v%lu.%lu\n",
sbi_major_version(), sbi_minor_version());
return 0;
}
static void sbi_set_power_off(void) {}
#endif /* CONFIG_RISCV_SBI_V01 */
static void __sbi_set_timer_v02(uint64_t stime_value)
{
#if __riscv_xlen == 32
sbi_ecall(SBI_EXT_TIME, SBI_EXT_TIME_SET_TIMER, stime_value,
stime_value >> 32, 0, 0, 0, 0);
#else
sbi_ecall(SBI_EXT_TIME, SBI_EXT_TIME_SET_TIMER, stime_value, 0,
0, 0, 0, 0);
#endif
}
static int __sbi_send_ipi_v02(const unsigned long *hart_mask)
{
unsigned long hartid, hmask_val, hbase;
struct cpumask tmask;
struct sbiret ret = {0};
int result;
if (!hart_mask || !(*hart_mask)) {
riscv_cpuid_to_hartid_mask(cpu_online_mask, &tmask);
hart_mask = cpumask_bits(&tmask);
}
hmask_val = 0;
hbase = 0;
for_each_set_bit(hartid, hart_mask, NR_CPUS) {
if (hmask_val && ((hbase + BITS_PER_LONG) <= hartid)) {
ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI,
hmask_val, hbase, 0, 0, 0, 0);
if (ret.error)
goto ecall_failed;
hmask_val = 0;
hbase = 0;
}
if (!hmask_val)
hbase = hartid;
hmask_val |= 1UL << (hartid - hbase);
}
if (hmask_val) {
ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI,
hmask_val, hbase, 0, 0, 0, 0);
if (ret.error)
goto ecall_failed;
}
return 0;
ecall_failed:
result = sbi_err_map_linux_errno(ret.error);
pr_err("%s: hbase = [%lu] hmask = [0x%lx] failed (error [%d])\n",
__func__, hbase, hmask_val, result);
return result;
}
static int __sbi_rfence_v02_call(unsigned long fid, unsigned long hmask_val,
unsigned long hbase, unsigned long start,
unsigned long size, unsigned long arg4,
unsigned long arg5)
{
struct sbiret ret = {0};
int ext = SBI_EXT_RFENCE;
int result = 0;
switch (fid) {
case SBI_EXT_RFENCE_REMOTE_FENCE_I:
ret = sbi_ecall(ext, fid, hmask_val, hbase, 0, 0, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, arg4, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, arg4, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID:
ret = sbi_ecall(ext, fid, hmask_val, hbase, start,
size, arg4, 0);
break;
default:
pr_err("unknown function ID [%lu] for SBI extension [%d]\n",
fid, ext);
result = -EINVAL;
}
if (ret.error) {
result = sbi_err_map_linux_errno(ret.error);
pr_err("%s: hbase = [%lu] hmask = [0x%lx] failed (error [%d])\n",
__func__, hbase, hmask_val, result);
}
return result;
}
static int __sbi_rfence_v02(int fid, const unsigned long *hart_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5)
{
unsigned long hmask_val, hartid, hbase;
struct cpumask tmask;
int result;
if (!hart_mask || !(*hart_mask)) {
riscv_cpuid_to_hartid_mask(cpu_online_mask, &tmask);
hart_mask = cpumask_bits(&tmask);
}
hmask_val = 0;
hbase = 0;
for_each_set_bit(hartid, hart_mask, NR_CPUS) {
if (hmask_val && ((hbase + BITS_PER_LONG) <= hartid)) {
result = __sbi_rfence_v02_call(fid, hmask_val, hbase,
start, size, arg4, arg5);
if (result)
return result;
hmask_val = 0;
hbase = 0;
}
if (!hmask_val)
hbase = hartid;
hmask_val |= 1UL << (hartid - hbase);
}
if (hmask_val) {
result = __sbi_rfence_v02_call(fid, hmask_val, hbase,
start, size, arg4, arg5);
if (result)
return result;
}
return 0;
}
/**
* sbi_set_timer() - Program the timer for next timer event.
* @stime_value: The value after which next timer event should fire.
*
* Return: None.
*/
void sbi_set_timer(uint64_t stime_value)
{
__sbi_set_timer(stime_value);
}
/**
* sbi_send_ipi() - Send an IPI to any hart.
* @hart_mask: A cpu mask containing all the target harts.
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_send_ipi(const unsigned long *hart_mask)
{
return __sbi_send_ipi(hart_mask);
}
EXPORT_SYMBOL(sbi_send_ipi);
/**
* sbi_remote_fence_i() - Execute FENCE.I instruction on given remote harts.
* @hart_mask: A cpu mask containing all the target harts.
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_remote_fence_i(const unsigned long *hart_mask)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_FENCE_I,
hart_mask, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_remote_fence_i);
/**
* sbi_remote_sfence_vma() - Execute SFENCE.VMA instructions on given remote
* harts for the specified virtual address range.
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the virtual address
* @size: Total size of the virtual address range.
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_remote_sfence_vma(const unsigned long *hart_mask,
unsigned long start,
unsigned long size)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA,
hart_mask, start, size, 0, 0);
}
EXPORT_SYMBOL(sbi_remote_sfence_vma);
/**
* sbi_remote_sfence_vma_asid() - Execute SFENCE.VMA instructions on given
* remote harts for a virtual address range belonging to a specific ASID.
*
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the virtual address
* @size: Total size of the virtual address range.
* @asid: The value of address space identifier (ASID).
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
unsigned long start,
unsigned long size,
unsigned long asid)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID,
hart_mask, start, size, asid, 0);
}
EXPORT_SYMBOL(sbi_remote_sfence_vma_asid);
/**
* sbi_remote_hfence_gvma() - Execute HFENCE.GVMA instructions on given remote
* harts for the specified guest physical address range.
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the guest physical address
* @size: Total size of the guest physical address range.
*
* Return: None
*/
int sbi_remote_hfence_gvma(const unsigned long *hart_mask,
unsigned long start,
unsigned long size)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA,
hart_mask, start, size, 0, 0);
}
EXPORT_SYMBOL_GPL(sbi_remote_hfence_gvma);
/**
* sbi_remote_hfence_gvma_vmid() - Execute HFENCE.GVMA instructions on given
* remote harts for a guest physical address range belonging to a specific VMID.
*
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the guest physical address
* @size: Total size of the guest physical address range.
* @vmid: The value of guest ID (VMID).
*
* Return: 0 if success, Error otherwise.
*/
int sbi_remote_hfence_gvma_vmid(const unsigned long *hart_mask,
unsigned long start,
unsigned long size,
unsigned long vmid)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID,
hart_mask, start, size, vmid, 0);
}
EXPORT_SYMBOL(sbi_remote_hfence_gvma_vmid);
/**
* sbi_remote_hfence_vvma() - Execute HFENCE.VVMA instructions on given remote
* harts for the current guest virtual address range.
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the current guest virtual address
* @size: Total size of the current guest virtual address range.
*
* Return: None
*/
int sbi_remote_hfence_vvma(const unsigned long *hart_mask,
unsigned long start,
unsigned long size)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA,
hart_mask, start, size, 0, 0);
}
EXPORT_SYMBOL(sbi_remote_hfence_vvma);
/**
* sbi_remote_hfence_vvma_asid() - Execute HFENCE.VVMA instructions on given
* remote harts for current guest virtual address range belonging to a specific
* ASID.
*
* @hart_mask: A cpu mask containing all the target harts.
* @start: Start of the current guest virtual address
* @size: Total size of the current guest virtual address range.
* @asid: The value of address space identifier (ASID).
*
* Return: None
*/
int sbi_remote_hfence_vvma_asid(const unsigned long *hart_mask,
unsigned long start,
unsigned long size,
unsigned long asid)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID,
hart_mask, start, size, asid, 0);
}
EXPORT_SYMBOL(sbi_remote_hfence_vvma_asid);
/**
* sbi_probe_extension() - Check if an SBI extension ID is supported or not.
* @extid: The extension ID to be probed.
*
* Return: Extension specific nonzero value f yes, -ENOTSUPP otherwise.
*/
int sbi_probe_extension(int extid)
{
struct sbiret ret;
ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid,
0, 0, 0, 0, 0);
if (!ret.error)
if (ret.value)
return ret.value;
return -ENOTSUPP;
}
EXPORT_SYMBOL(sbi_probe_extension);
static long __sbi_base_ecall(int fid)
{
struct sbiret ret;
ret = sbi_ecall(SBI_EXT_BASE, fid, 0, 0, 0, 0, 0, 0);
if (!ret.error)
return ret.value;
else
return sbi_err_map_linux_errno(ret.error);
}
static inline long sbi_get_spec_version(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_SPEC_VERSION);
}
static inline long sbi_get_firmware_id(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_ID);
}
static inline long sbi_get_firmware_version(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_VERSION);
}
static void sbi_send_cpumask_ipi(const struct cpumask *target)
{
struct cpumask hartid_mask;
riscv_cpuid_to_hartid_mask(target, &hartid_mask);
sbi_send_ipi(cpumask_bits(&hartid_mask));
}
static struct riscv_ipi_ops sbi_ipi_ops = {
.ipi_inject = sbi_send_cpumask_ipi
};
void __init sbi_init(void)
{
int ret;
sbi_set_power_off();
ret = sbi_get_spec_version();
if (ret > 0)
sbi_spec_version = ret;
pr_info("SBI specification v%lu.%lu detected\n",
sbi_major_version(), sbi_minor_version());
if (!sbi_spec_is_0_1()) {
pr_info("SBI implementation ID=0x%lx Version=0x%lx\n",
sbi_get_firmware_id(), sbi_get_firmware_version());
if (sbi_probe_extension(SBI_EXT_TIME) > 0) {
__sbi_set_timer = __sbi_set_timer_v02;
pr_info("SBI v0.2 TIME extension detected\n");
} else {
__sbi_set_timer = __sbi_set_timer_v01;
}
if (sbi_probe_extension(SBI_EXT_IPI) > 0) {
__sbi_send_ipi = __sbi_send_ipi_v02;
pr_info("SBI v0.2 IPI extension detected\n");
} else {
__sbi_send_ipi = __sbi_send_ipi_v01;
}
if (sbi_probe_extension(SBI_EXT_RFENCE) > 0) {
__sbi_rfence = __sbi_rfence_v02;
pr_info("SBI v0.2 RFENCE extension detected\n");
} else {
__sbi_rfence = __sbi_rfence_v01;
}
} else {
__sbi_set_timer = __sbi_set_timer_v01;
__sbi_send_ipi = __sbi_send_ipi_v01;
__sbi_rfence = __sbi_rfence_v01;
}
riscv_set_ipi_ops(&sbi_ipi_ops);
}