diff options
Diffstat (limited to 'arch/riscv/kernel/suspend.c')
| -rw-r--r-- | arch/riscv/kernel/suspend.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/riscv/kernel/suspend.c b/arch/riscv/kernel/suspend.c index 3c89b8ec6..299795341 100644 --- a/arch/riscv/kernel/suspend.c +++ b/arch/riscv/kernel/suspend.c @@ -4,13 +4,19 @@ * Copyright (c) 2022 Ventana Micro Systems Inc. */ +#define pr_fmt(fmt) "suspend: " fmt + #include <linux/ftrace.h> +#include <linux/suspend.h> #include <asm/csr.h> +#include <asm/sbi.h> #include <asm/suspend.h> void suspend_save_csrs(struct suspend_context *context) { context->scratch = csr_read(CSR_SCRATCH); + if (riscv_cpu_has_extension_unlikely(smp_processor_id(), RISCV_ISA_EXT_XLINUXENVCFG)) + context->envcfg = csr_read(CSR_ENVCFG); context->tvec = csr_read(CSR_TVEC); context->ie = csr_read(CSR_IE); @@ -32,6 +38,8 @@ void suspend_save_csrs(struct suspend_context *context) void suspend_restore_csrs(struct suspend_context *context) { csr_write(CSR_SCRATCH, context->scratch); + if (riscv_cpu_has_extension_unlikely(smp_processor_id(), RISCV_ISA_EXT_XLINUXENVCFG)) + csr_write(CSR_ENVCFG, context->envcfg); csr_write(CSR_TVEC, context->tvec); csr_write(CSR_IE, context->ie); @@ -85,3 +93,43 @@ int cpu_suspend(unsigned long arg, return rc; } + +#ifdef CONFIG_RISCV_SBI +static int sbi_system_suspend(unsigned long sleep_type, + unsigned long resume_addr, + unsigned long opaque) +{ + struct sbiret ret; + + ret = sbi_ecall(SBI_EXT_SUSP, SBI_EXT_SUSP_SYSTEM_SUSPEND, + sleep_type, resume_addr, opaque, 0, 0, 0); + if (ret.error) + return sbi_err_map_linux_errno(ret.error); + + return ret.value; +} + +static int sbi_system_suspend_enter(suspend_state_t state) +{ + return cpu_suspend(SBI_SUSP_SLEEP_TYPE_SUSPEND_TO_RAM, sbi_system_suspend); +} + +static const struct platform_suspend_ops sbi_system_suspend_ops = { + .valid = suspend_valid_only_mem, + .enter = sbi_system_suspend_enter, +}; + +static int __init sbi_system_suspend_init(void) +{ + if (sbi_spec_version >= sbi_mk_version(2, 0) && + sbi_probe_extension(SBI_EXT_SUSP) > 0) { + pr_info("SBI SUSP extension detected\n"); + if (IS_ENABLED(CONFIG_SUSPEND)) + suspend_set_ops(&sbi_system_suspend_ops); + } + + return 0; +} + +arch_initcall(sbi_system_suspend_init); +#endif /* CONFIG_RISCV_SBI */ |