diff options
Diffstat (limited to 'arch/arm64/kernel/psci.c')
-rw-r--r-- | arch/arm64/kernel/psci.c | 375 |
1 files changed, 308 insertions, 67 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 14f73c445ff5..fc457d0fee9c 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -15,97 +15,109 @@ #define pr_fmt(fmt) "psci: " fmt +#include <linux/cpuidle.h> #include <linux/init.h> #include <linux/of.h> +#include <linux/smp.h> +#include <linux/slab.h> +#include <linux/reboot.h> +#include <linux/pm.h> +#include <linux/delay.h> +#include <uapi/linux/psci.h> #include <asm/compiler.h> +#include <asm/cpu_ops.h> #include <asm/errno.h> #include <asm/psci.h> +#include <asm/smp_plat.h> +#include <asm/suspend.h> +#include <asm/system_misc.h> -struct psci_operations psci_ops; +#define PSCI_POWER_STATE_TYPE_STANDBY 0 +#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1 + +struct psci_power_state { + u16 id; + u8 type; + u8 affinity_level; +}; + +struct psci_operations { + int (*cpu_suspend)(struct psci_power_state state, + unsigned long entry_point); + int (*cpu_off)(struct psci_power_state state); + int (*cpu_on)(unsigned long cpuid, unsigned long entry_point); + int (*migrate)(unsigned long cpuid); + int (*affinity_info)(unsigned long target_affinity, + unsigned long lowest_affinity_level); + int (*migrate_info_type)(void); +}; + +static struct psci_operations psci_ops; static int (*invoke_psci_fn)(u64, u64, u64, u64); +typedef int (*psci_initcall_t)(const struct device_node *); + +asmlinkage int __invoke_psci_fn_hvc(u64, u64, u64, u64); +asmlinkage int __invoke_psci_fn_smc(u64, u64, u64, u64); enum psci_function { PSCI_FN_CPU_SUSPEND, PSCI_FN_CPU_ON, PSCI_FN_CPU_OFF, PSCI_FN_MIGRATE, + PSCI_FN_AFFINITY_INFO, + PSCI_FN_MIGRATE_INFO_TYPE, PSCI_FN_MAX, }; -static u32 psci_function_id[PSCI_FN_MAX]; +static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); -#define PSCI_RET_SUCCESS 0 -#define PSCI_RET_EOPNOTSUPP -1 -#define PSCI_RET_EINVAL -2 -#define PSCI_RET_EPERM -3 +static u32 psci_function_id[PSCI_FN_MAX]; static int psci_to_linux_errno(int errno) { switch (errno) { case PSCI_RET_SUCCESS: return 0; - case PSCI_RET_EOPNOTSUPP: + case PSCI_RET_NOT_SUPPORTED: return -EOPNOTSUPP; - case PSCI_RET_EINVAL: + case PSCI_RET_INVALID_PARAMS: return -EINVAL; - case PSCI_RET_EPERM: + case PSCI_RET_DENIED: return -EPERM; }; return -EINVAL; } -#define PSCI_POWER_STATE_ID_MASK 0xffff -#define PSCI_POWER_STATE_ID_SHIFT 0 -#define PSCI_POWER_STATE_TYPE_MASK 0x1 -#define PSCI_POWER_STATE_TYPE_SHIFT 16 -#define PSCI_POWER_STATE_AFFL_MASK 0x3 -#define PSCI_POWER_STATE_AFFL_SHIFT 24 - static u32 psci_power_state_pack(struct psci_power_state state) { - return ((state.id & PSCI_POWER_STATE_ID_MASK) - << PSCI_POWER_STATE_ID_SHIFT) | - ((state.type & PSCI_POWER_STATE_TYPE_MASK) - << PSCI_POWER_STATE_TYPE_SHIFT) | - ((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK) - << PSCI_POWER_STATE_AFFL_SHIFT); + return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT) + & PSCI_0_2_POWER_STATE_ID_MASK) | + ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT) + & PSCI_0_2_POWER_STATE_TYPE_MASK) | + ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT) + & PSCI_0_2_POWER_STATE_AFFL_MASK); } -/* - * The following two functions are invoked via the invoke_psci_fn pointer - * and will not be inlined, allowing us to piggyback on the AAPCS. - */ -static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1, - u64 arg2) +static void psci_power_state_unpack(u32 power_state, + struct psci_power_state *state) { - asm volatile( - __asmeq("%0", "x0") - __asmeq("%1", "x1") - __asmeq("%2", "x2") - __asmeq("%3", "x3") - "hvc #0\n" - : "+r" (function_id) - : "r" (arg0), "r" (arg1), "r" (arg2)); - - return function_id; + state->id = (power_state >> PSCI_0_2_POWER_STATE_ID_SHIFT) + & PSCI_0_2_POWER_STATE_ID_MASK; + state->type = (power_state >> PSCI_0_2_POWER_STATE_TYPE_SHIFT) + & PSCI_0_2_POWER_STATE_TYPE_MASK; + state->affinity_level = (power_state >> PSCI_0_2_POWER_STATE_AFFL_SHIFT) + & PSCI_0_2_POWER_STATE_AFFL_MASK; } -static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1, - u64 arg2) +static int psci_get_version(void) { - asm volatile( - __asmeq("%0", "x0") - __asmeq("%1", "x1") - __asmeq("%2", "x2") - __asmeq("%3", "x3") - "smc #0\n" - : "+r" (function_id) - : "r" (arg0), "r" (arg1), "r" (arg2)); + int err; - return function_id; + err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0); + return err; } static int psci_cpu_suspend(struct psci_power_state state, @@ -151,28 +163,36 @@ static int psci_migrate(unsigned long cpuid) return psci_to_linux_errno(err); } -static const struct of_device_id psci_of_match[] __initconst = { - { .compatible = "arm,psci", }, - {}, -}; +static int psci_affinity_info(unsigned long target_affinity, + unsigned long lowest_affinity_level) +{ + int err; + u32 fn; -int __init psci_init(void) + fn = psci_function_id[PSCI_FN_AFFINITY_INFO]; + err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0); + return err; +} + +static int psci_migrate_info_type(void) { - struct device_node *np; - const char *method; - u32 id; - int err = 0; + int err; + u32 fn; - np = of_find_matching_node(NULL, psci_of_match); - if (!np) - return -ENODEV; + fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE]; + err = invoke_psci_fn(fn, 0, 0, 0); + return err; +} - pr_info("probing function IDs from device-tree\n"); +static int get_set_conduit_method(struct device_node *np) +{ + const char *method; + + pr_info("probing for conduit method from DT.\n"); if (of_property_read_string(np, "method", &method)) { - pr_warning("missing \"method\" property\n"); - err = -ENXIO; - goto out_put_node; + pr_warn("missing \"method\" property\n"); + return -ENXIO; } if (!strcmp("hvc", method)) { @@ -180,11 +200,99 @@ int __init psci_init(void) } else if (!strcmp("smc", method)) { invoke_psci_fn = __invoke_psci_fn_smc; } else { - pr_warning("invalid \"method\" property: %s\n", method); - err = -EINVAL; + pr_warn("invalid \"method\" property: %s\n", method); + return -EINVAL; + } + return 0; +} + +static void psci_sys_reset(char str, const char *cmd) +{ + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); +} + +static void psci_sys_poweroff(void) +{ + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); +} + +/* + * PSCI Function IDs for v0.2+ are well defined so use + * standard values. + */ +static int __init psci_0_2_init(struct device_node *np) +{ + int err, ver; + + err = get_set_conduit_method(np); + + if (err) + goto out_put_node; + + ver = psci_get_version(); + + if (ver == PSCI_RET_NOT_SUPPORTED) { + /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */ + pr_err("PSCI firmware does not comply with the v0.2 spec.\n"); + err = -EOPNOTSUPP; goto out_put_node; + } else { + pr_info("PSCIv%d.%d detected in firmware.\n", + PSCI_VERSION_MAJOR(ver), + PSCI_VERSION_MINOR(ver)); + + if (PSCI_VERSION_MAJOR(ver) == 0 && + PSCI_VERSION_MINOR(ver) < 2) { + err = -EINVAL; + pr_err("Conflicting PSCI version detected.\n"); + goto out_put_node; + } } + pr_info("Using standard PSCI v0.2 function IDs\n"); + psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND; + psci_ops.cpu_suspend = psci_cpu_suspend; + + psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF; + psci_ops.cpu_off = psci_cpu_off; + + psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON; + psci_ops.cpu_on = psci_cpu_on; + + psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE; + psci_ops.migrate = psci_migrate; + + psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO; + psci_ops.affinity_info = psci_affinity_info; + + psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] = + PSCI_0_2_FN_MIGRATE_INFO_TYPE; + psci_ops.migrate_info_type = psci_migrate_info_type; + + arm_pm_restart = psci_sys_reset; + + pm_power_off = psci_sys_poweroff; + +out_put_node: + of_node_put(np); + return err; +} + +/* + * PSCI < v0.2 get PSCI Function IDs via DT. + */ +static int __init psci_0_1_init(struct device_node *np) +{ + u32 id; + int err; + + err = get_set_conduit_method(np); + + if (err) + goto out_put_node; + + pr_info("Using PSCI v0.1 Function IDs from DT\n"); + if (!of_property_read_u32(np, "cpu_suspend", &id)) { psci_function_id[PSCI_FN_CPU_SUSPEND] = id; psci_ops.cpu_suspend = psci_cpu_suspend; @@ -209,3 +317,136 @@ out_put_node: of_node_put(np); return err; } + +static const struct of_device_id psci_of_match[] __initconst = { + { .compatible = "arm,psci", .data = psci_0_1_init}, + { .compatible = "arm,psci-0.2", .data = psci_0_2_init}, + {}, +}; + +int __init psci_init(void) +{ + struct device_node *np; + const struct of_device_id *matched_np; + psci_initcall_t init_fn; + + np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np); + + if (!np) + return -ENODEV; + + init_fn = (psci_initcall_t)matched_np->data; + return init_fn(np); +} + +#ifdef CONFIG_SMP + +static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu) +{ + return 0; +} + +static int __init cpu_psci_cpu_prepare(unsigned int cpu) +{ + if (!psci_ops.cpu_on) { + pr_err("no cpu_on method, not booting CPU%d\n", cpu); + return -ENODEV; + } + + return 0; +} + +static int cpu_psci_cpu_boot(unsigned int cpu) +{ + int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry)); + if (err) + pr_err("failed to boot CPU%d (%d)\n", cpu, err); + + return err; +} + +#ifdef CONFIG_HOTPLUG_CPU +static int cpu_psci_cpu_disable(unsigned int cpu) +{ + /* Fail early if we don't have CPU_OFF support */ + if (!psci_ops.cpu_off) + return -EOPNOTSUPP; + return 0; +} + +static void cpu_psci_cpu_die(unsigned int cpu) +{ + int ret; + /* + * There are no known implementations of PSCI actually using the + * power state field, pass a sensible default for now. + */ + struct psci_power_state state = { + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, + }; + + ret = psci_ops.cpu_off(state); + + pr_crit("unable to power off CPU%u (%d)\n", cpu, ret); +} + +static int cpu_psci_cpu_kill(unsigned int cpu) +{ + int err, i; + + if (!psci_ops.affinity_info) + return 1; + /* + * cpu_kill could race with cpu_die and we can + * potentially end up declaring this cpu undead + * while it is dying. So, try again a few times. + */ + + for (i = 0; i < 10; i++) { + err = psci_ops.affinity_info(cpu_logical_map(cpu), 0); + if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) { + pr_info("CPU%d killed.\n", cpu); + return 1; + } + + msleep(10); + pr_info("Retrying again to check for CPU kill\n"); + } + + pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n", + cpu, err); + /* Make op_cpu_kill() fail. */ + return 0; +} +#endif +#endif + +#ifdef CONFIG_ARM64_CPU_SUSPEND +static int cpu_psci_cpu_suspend(unsigned long index) +{ + struct psci_power_state *state = __get_cpu_var(psci_power_state); + + if (!state) + return -EOPNOTSUPP; + + return psci_ops.cpu_suspend(state[index], virt_to_phys(cpu_resume)); +} +#endif + +const struct cpu_operations cpu_psci_ops = { + .name = "psci", +#ifdef CONFIG_SMP + .cpu_init = cpu_psci_cpu_init, + .cpu_prepare = cpu_psci_cpu_prepare, + .cpu_boot = cpu_psci_cpu_boot, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_disable = cpu_psci_cpu_disable, + .cpu_die = cpu_psci_cpu_die, + .cpu_kill = cpu_psci_cpu_kill, +#endif +#endif +#ifdef CONFIG_ARM64_CPU_SUSPEND + .cpu_suspend = cpu_psci_cpu_suspend, +#endif +}; + |