// 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);
static 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;
};
}
#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_set_timer);
/**
* 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_shutdown);
/**
* 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;
}
#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;
}
#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: None
*/
void sbi_send_ipi(const unsigned long *hart_mask)
{
__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: None
*/
void sbi_remote_fence_i(const unsigned long *hart_mask)
{
__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: None
*/
void sbi_remote_sfence_vma(const unsigned long *hart_mask,
unsigned long start,
unsigned long size)
{
__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: None
*/
void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
unsigned long start,
unsigned long size,
unsigned long asid)
{
__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_power_off(void)
{
sbi_shutdown();
}
int __init sbi_init(void)
{
int ret;
pm_power_off = sbi_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;
}
return 0;
}
