blob: e66e0999a80057058c66c71fa907a0fb0152bc00 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* SBI initialilization and all extension implementation.
*
* Copyright (c) 2020 Western Digital Corporation or its affiliates.
*/
#include <linux/bits.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/pm.h>
#include <linux/reboot.h>
#include <asm/sbi.h>
#include <asm/smp.h>
#include <asm/tlbflush.h>
/* default SBI version is 0.1 */
unsigned long sbi_spec_version __ro_after_init = SBI_SPEC_VERSION_DEFAULT;
EXPORT_SYMBOL(sbi_spec_version);
static void (*__sbi_set_timer)(uint64_t stime) __ro_after_init;
static void (*__sbi_send_ipi)(unsigned int cpu) __ro_after_init;
static int (*__sbi_rfence)(int fid, const struct cpumask *cpu_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5) __ro_after_init;
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
static unsigned long __sbi_v01_cpumask_to_hartmask(const struct cpumask *cpu_mask)
{
unsigned long cpuid, hartid;
unsigned long hmask = 0;
/*
* There is no maximum hartid concept in RISC-V and NR_CPUS must not be
* associated with hartid. As SBI v0.1 is only kept for backward compatibility
* and will be removed in the future, there is no point in supporting hartid
* greater than BITS_PER_LONG (32 for RV32 and 64 for RV64). Ideally, SBI v0.2
* should be used for platforms with hartid greater than BITS_PER_LONG.
*/
for_each_cpu(cpuid, cpu_mask) {
hartid = cpuid_to_hartid_map(cpuid);
if (hartid >= BITS_PER_LONG) {
pr_warn("Unable to send any request to hartid > BITS_PER_LONG for SBI v0.1\n");
break;
}
hmask |= BIT(hartid);
}
return hmask;
}
/**
* 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_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 void __sbi_send_ipi_v01(unsigned int cpu)
{
unsigned long hart_mask =
__sbi_v01_cpumask_to_hartmask(cpumask_of(cpu));
sbi_ecall(SBI_EXT_0_1_SEND_IPI, 0, (unsigned long)(&hart_mask),
0, 0, 0, 0, 0);
}
static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5)
{
int result = 0;
unsigned long hart_mask;
if (!cpu_mask || cpumask_empty(cpu_mask))
cpu_mask = cpu_online_mask;
hart_mask = __sbi_v01_cpumask_to_hartmask(cpu_mask);
/* 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 void __sbi_send_ipi_v01(unsigned int cpu)
{
pr_warn("IPI extension is not available in SBI v%lu.%lu\n",
sbi_major_version(), sbi_minor_version());
}
static int __sbi_rfence_v01(int fid, const struct cpumask *cpu_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 void __sbi_send_ipi_v02(unsigned int cpu)
{
int result;
struct sbiret ret = {0};
ret = sbi_ecall(SBI_EXT_IPI, SBI_EXT_IPI_SEND_IPI,
1UL, cpuid_to_hartid_map(cpu), 0, 0, 0, 0);
if (ret.error) {
result = sbi_err_map_linux_errno(ret.error);
pr_err("%s: hbase = [%lu] failed (error [%d])\n",
__func__, cpuid_to_hartid_map(cpu), result);
}
}
static int __sbi_rfence_v02_call(unsigned long fid, unsigned long hmask,
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, hbase, 0, 0, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA:
ret = sbi_ecall(ext, fid, hmask, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID:
ret = sbi_ecall(ext, fid, hmask, hbase, start,
size, arg4, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA:
ret = sbi_ecall(ext, fid, hmask, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID:
ret = sbi_ecall(ext, fid, hmask, hbase, start,
size, arg4, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA:
ret = sbi_ecall(ext, fid, hmask, hbase, start,
size, 0, 0);
break;
case SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID:
ret = sbi_ecall(ext, fid, hmask, 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, result);
}
return result;
}
static int __sbi_rfence_v02(int fid, const struct cpumask *cpu_mask,
unsigned long start, unsigned long size,
unsigned long arg4, unsigned long arg5)
{
unsigned long hartid, cpuid, hmask = 0, hbase = 0, htop = 0;
int result;
if (!cpu_mask || cpumask_empty(cpu_mask))
cpu_mask = cpu_online_mask;
for_each_cpu(cpuid, cpu_mask) {
hartid = cpuid_to_hartid_map(cpuid);
if (hmask) {
if (hartid + BITS_PER_LONG <= htop ||
hbase + BITS_PER_LONG <= hartid) {
result = __sbi_rfence_v02_call(fid, hmask,
hbase, start, size, arg4, arg5);
if (result)
return result;
hmask = 0;
} else if (hartid < hbase) {
/* shift the mask to fit lower hartid */
hmask <<= hbase - hartid;
hbase = hartid;
}
}
if (!hmask) {
hbase = hartid;
htop = hartid;
} else if (hartid > htop) {
htop = hartid;
}
hmask |= BIT(hartid - hbase);
}
if (hmask) {
result = __sbi_rfence_v02_call(fid, hmask, 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.
* @cpu: Logical id of the target CPU.
*/
void sbi_send_ipi(unsigned int cpu)
{
__sbi_send_ipi(cpu);
}
EXPORT_SYMBOL(sbi_send_ipi);
/**
* sbi_remote_fence_i() - Execute FENCE.I instruction on given remote harts.
* @cpu_mask: A cpu mask containing all the target harts.
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_remote_fence_i(const struct cpumask *cpu_mask)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_FENCE_I,
cpu_mask, 0, 0, 0, 0);
}
EXPORT_SYMBOL(sbi_remote_fence_i);
/**
* sbi_remote_sfence_vma_asid() - Execute SFENCE.VMA instructions on given
* remote harts for a virtual address range belonging to a specific ASID or not.
*
* @cpu_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), or FLUSH_TLB_NO_ASID
* for flushing all address spaces.
*
* Return: 0 on success, appropriate linux error code otherwise.
*/
int sbi_remote_sfence_vma_asid(const struct cpumask *cpu_mask,
unsigned long start,
unsigned long size,
unsigned long asid)
{
if (asid == FLUSH_TLB_NO_ASID)
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA,
cpu_mask, start, size, 0, 0);
else
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA_ASID,
cpu_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.
* @cpu_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 struct cpumask *cpu_mask,
unsigned long start,
unsigned long size)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA,
cpu_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.
*
* @cpu_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 struct cpumask *cpu_mask,
unsigned long start,
unsigned long size,
unsigned long vmid)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_GVMA_VMID,
cpu_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.
* @cpu_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 struct cpumask *cpu_mask,
unsigned long start,
unsigned long size)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA,
cpu_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.
*
* @cpu_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 struct cpumask *cpu_mask,
unsigned long start,
unsigned long size,
unsigned long asid)
{
return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_HFENCE_VVMA_ASID,
cpu_mask, start, size, asid, 0);
}
EXPORT_SYMBOL(sbi_remote_hfence_vvma_asid);
static void sbi_srst_reset(unsigned long type, unsigned long reason)
{
sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason,
0, 0, 0, 0);
pr_warn("%s: type=0x%lx reason=0x%lx failed\n",
__func__, type, reason);
}
static int sbi_srst_reboot(struct notifier_block *this,
unsigned long mode, void *cmd)
{
sbi_srst_reset((mode == REBOOT_WARM || mode == REBOOT_SOFT) ?
SBI_SRST_RESET_TYPE_WARM_REBOOT :
SBI_SRST_RESET_TYPE_COLD_REBOOT,
SBI_SRST_RESET_REASON_NONE);
return NOTIFY_DONE;
}
static struct notifier_block sbi_srst_reboot_nb;
static void sbi_srst_power_off(void)
{
sbi_srst_reset(SBI_SRST_RESET_TYPE_SHUTDOWN,
SBI_SRST_RESET_REASON_NONE);
}
/**
* sbi_probe_extension() - Check if an SBI extension ID is supported or not.
* @extid: The extension ID to be probed.
*
* Return: 1 or an extension specific nonzero value if yes, 0 otherwise.
*/
long 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)
return ret.value;
return 0;
}
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);
}
long sbi_get_mvendorid(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_MVENDORID);
}
EXPORT_SYMBOL_GPL(sbi_get_mvendorid);
long sbi_get_marchid(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_MARCHID);
}
EXPORT_SYMBOL_GPL(sbi_get_marchid);
long sbi_get_mimpid(void)
{
return __sbi_base_ecall(SBI_EXT_BASE_GET_MIMPID);
}
EXPORT_SYMBOL_GPL(sbi_get_mimpid);
bool sbi_debug_console_available;
int sbi_debug_console_write(const char *bytes, unsigned int num_bytes)
{
phys_addr_t base_addr;
struct sbiret ret;
if (!sbi_debug_console_available)
return -EOPNOTSUPP;
if (is_vmalloc_addr(bytes))
base_addr = page_to_phys(vmalloc_to_page(bytes)) +
offset_in_page(bytes);
else
base_addr = __pa(bytes);
if (PAGE_SIZE < (offset_in_page(bytes) + num_bytes))
num_bytes = PAGE_SIZE - offset_in_page(bytes);
if (IS_ENABLED(CONFIG_32BIT))
ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
num_bytes, lower_32_bits(base_addr),
upper_32_bits(base_addr), 0, 0, 0);
else
ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
num_bytes, base_addr, 0, 0, 0, 0);
if (ret.error == SBI_ERR_FAILURE)
return -EIO;
return ret.error ? sbi_err_map_linux_errno(ret.error) : ret.value;
}
int sbi_debug_console_read(char *bytes, unsigned int num_bytes)
{
phys_addr_t base_addr;
struct sbiret ret;
if (!sbi_debug_console_available)
return -EOPNOTSUPP;
if (is_vmalloc_addr(bytes))
base_addr = page_to_phys(vmalloc_to_page(bytes)) +
offset_in_page(bytes);
else
base_addr = __pa(bytes);
if (PAGE_SIZE < (offset_in_page(bytes) + num_bytes))
num_bytes = PAGE_SIZE - offset_in_page(bytes);
if (IS_ENABLED(CONFIG_32BIT))
ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
num_bytes, lower_32_bits(base_addr),
upper_32_bits(base_addr), 0, 0, 0);
else
ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
num_bytes, base_addr, 0, 0, 0, 0);
if (ret.error == SBI_ERR_FAILURE)
return -EIO;
return ret.error ? sbi_err_map_linux_errno(ret.error) : ret.value;
}
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)) {
__sbi_set_timer = __sbi_set_timer_v02;
pr_info("SBI TIME extension detected\n");
} else {
__sbi_set_timer = __sbi_set_timer_v01;
}
if (sbi_probe_extension(SBI_EXT_IPI)) {
__sbi_send_ipi = __sbi_send_ipi_v02;
pr_info("SBI IPI extension detected\n");
} else {
__sbi_send_ipi = __sbi_send_ipi_v01;
}
if (sbi_probe_extension(SBI_EXT_RFENCE)) {
__sbi_rfence = __sbi_rfence_v02;
pr_info("SBI RFENCE extension detected\n");
} else {
__sbi_rfence = __sbi_rfence_v01;
}
if ((sbi_spec_version >= sbi_mk_version(0, 3)) &&
sbi_probe_extension(SBI_EXT_SRST)) {
pr_info("SBI SRST extension detected\n");
pm_power_off = sbi_srst_power_off;
sbi_srst_reboot_nb.notifier_call = sbi_srst_reboot;
sbi_srst_reboot_nb.priority = 192;
register_restart_handler(&sbi_srst_reboot_nb);
}
if ((sbi_spec_version >= sbi_mk_version(2, 0)) &&
(sbi_probe_extension(SBI_EXT_DBCN) > 0)) {
pr_info("SBI DBCN extension detected\n");
sbi_debug_console_available = true;
}
} else {
__sbi_set_timer = __sbi_set_timer_v01;
__sbi_send_ipi = __sbi_send_ipi_v01;
__sbi_rfence = __sbi_rfence_v01;
}
}