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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/riscv/kernel/sbi.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/kernel/sbi.c')
-rw-r--r--arch/riscv/kernel/sbi.c632
1 files changed, 632 insertions, 0 deletions
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
new file mode 100644
index 0000000000..c672c8ba9a
--- /dev/null
+++ b/arch/riscv/kernel/sbi.c
@@ -0,0 +1,632 @@
+// 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/pm.h>
+#include <linux/reboot.h>
+#include <asm/sbi.h>
+#include <asm/smp.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() - Execute SFENCE.VMA instructions on given remote
+ * harts for the specified virtual address range.
+ * @cpu_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 struct cpumask *cpu_mask,
+ unsigned long start,
+ unsigned long size)
+{
+ return __sbi_rfence(SBI_EXT_RFENCE_REMOTE_SFENCE_VMA,
+ cpu_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.
+ *
+ * @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).
+ *
+ * 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)
+{
+ 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);
+
+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);
+ }
+ } else {
+ __sbi_set_timer = __sbi_set_timer_v01;
+ __sbi_send_ipi = __sbi_send_ipi_v01;
+ __sbi_rfence = __sbi_rfence_v01;
+ }
+}