diff options
Diffstat (limited to 'arch/riscv/kernel/sbi.c')
| -rw-r--r-- | arch/riscv/kernel/sbi.c | 605 |
1 files changed, 605 insertions, 0 deletions
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c new file mode 100644 index 000000000..226ccce0f --- /dev/null +++ b/arch/riscv/kernel/sbi.c @@ -0,0 +1,605 @@ +// 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: 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_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 +}; + +int __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); + + return 0; +} |