diff options
Diffstat (limited to 'arch/arm64/kernel/psci.c')
| -rw-r--r-- | arch/arm64/kernel/psci.c | 244 |
1 files changed, 136 insertions, 108 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index ea18cb53921e..869f202748e8 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -15,7 +15,6 @@ #define pr_fmt(fmt) "psci: " fmt -#include <linux/acpi.h> #include <linux/init.h> #include <linux/of.h> #include <linux/smp.h> @@ -25,8 +24,8 @@ #include <linux/slab.h> #include <uapi/linux/psci.h> -#include <asm/acpi.h> #include <asm/compiler.h> +#include <asm/cputype.h> #include <asm/cpu_ops.h> #include <asm/errno.h> #include <asm/psci.h> @@ -37,16 +36,31 @@ #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; -}; +static bool psci_power_state_loses_context(u32 state) +{ + return state & PSCI_0_2_POWER_STATE_TYPE_MASK; +} + +static bool psci_power_state_is_valid(u32 state) +{ + const u32 valid_mask = PSCI_0_2_POWER_STATE_ID_MASK | + PSCI_0_2_POWER_STATE_TYPE_MASK | + PSCI_0_2_POWER_STATE_AFFL_MASK; + + return !(state & ~valid_mask); +} + +/* + * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF + * calls to its resident CPU, so we must avoid issuing those. We never migrate + * a Trusted OS even if it claims to be capable of migration -- doing so will + * require cooperation with a Trusted OS driver. + */ +static int resident_cpu = -1; 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_suspend)(u32 state, unsigned long entry_point); + int (*cpu_off)(u32 state); int (*cpu_on)(unsigned long cpuid, unsigned long entry_point); int (*migrate)(unsigned long cpuid); int (*affinity_info)(unsigned long target_affinity, @@ -56,23 +70,21 @@ struct psci_operations { 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); +typedef unsigned long (psci_fn)(unsigned long, unsigned long, + unsigned long, unsigned long); +asmlinkage psci_fn __invoke_psci_fn_hvc; +asmlinkage psci_fn __invoke_psci_fn_smc; +static psci_fn *invoke_psci_fn; 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 DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); +static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state); static u32 psci_function_id[PSCI_FN_MAX]; @@ -92,56 +104,28 @@ static int psci_to_linux_errno(int errno) return -EINVAL; } -static u32 psci_power_state_pack(struct psci_power_state state) -{ - 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); -} - -static void psci_power_state_unpack(u32 power_state, - struct psci_power_state *state) -{ - state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >> - PSCI_0_2_POWER_STATE_ID_SHIFT; - state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >> - PSCI_0_2_POWER_STATE_TYPE_SHIFT; - state->affinity_level = - (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >> - PSCI_0_2_POWER_STATE_AFFL_SHIFT; -} - -static int psci_get_version(void) +static u32 psci_get_version(void) { - int err; - - err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0); - return err; + return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0); } -static int psci_cpu_suspend(struct psci_power_state state, - unsigned long entry_point) +static int psci_cpu_suspend(u32 state, unsigned long entry_point) { int err; - u32 fn, power_state; + u32 fn; fn = psci_function_id[PSCI_FN_CPU_SUSPEND]; - power_state = psci_power_state_pack(state); - err = invoke_psci_fn(fn, power_state, entry_point, 0); + err = invoke_psci_fn(fn, state, entry_point, 0); return psci_to_linux_errno(err); } -static int psci_cpu_off(struct psci_power_state state) +static int psci_cpu_off(u32 state) { int err; - u32 fn, power_state; + u32 fn; fn = psci_function_id[PSCI_FN_CPU_OFF]; - power_state = psci_power_state_pack(state); - err = invoke_psci_fn(fn, power_state, 0, 0); + err = invoke_psci_fn(fn, state, 0, 0); return psci_to_linux_errno(err); } @@ -168,30 +152,29 @@ static int psci_migrate(unsigned long cpuid) static int psci_affinity_info(unsigned long target_affinity, unsigned long lowest_affinity_level) { - int err; - u32 fn; - - fn = psci_function_id[PSCI_FN_AFFINITY_INFO]; - err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0); - return err; + return invoke_psci_fn(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, + lowest_affinity_level, 0); } static int psci_migrate_info_type(void) { - int err; - u32 fn; + return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0); +} - fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE]; - err = invoke_psci_fn(fn, 0, 0, 0); - return err; +static unsigned long psci_migrate_info_up_cpu(void) +{ + return invoke_psci_fn(PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU, 0, 0, 0); } -static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node, - unsigned int cpu) +static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu) { int i, ret, count = 0; - struct psci_power_state *psci_states; - struct device_node *state_node; + u32 *psci_states; + struct device_node *state_node, *cpu_node; + + cpu_node = of_get_cpu_node(cpu, NULL); + if (!cpu_node) + return -ENODEV; /* * If the PSCI cpu_suspend function hook has not been initialized @@ -215,13 +198,13 @@ static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node, return -ENOMEM; for (i = 0; i < count; i++) { - u32 psci_power_state; + u32 state; state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); ret = of_property_read_u32(state_node, "arm,psci-suspend-param", - &psci_power_state); + &state); if (ret) { pr_warn(" * %s missing arm,psci-suspend-param property\n", state_node->full_name); @@ -230,9 +213,13 @@ static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node, } of_node_put(state_node); - pr_debug("psci-power-state %#x index %d\n", psci_power_state, - i); - psci_power_state_unpack(psci_power_state, &psci_states[i]); + pr_debug("psci-power-state %#x index %d\n", state, i); + if (!psci_power_state_is_valid(state)) { + pr_warn("Invalid PSCI power state %#x\n", state); + ret = -EINVAL; + goto free_mem; + } + psci_states[i] = state; } /* Idle states parsed correctly, initialize per-cpu pointer */ per_cpu(psci_power_state, cpu) = psci_states; @@ -275,6 +262,46 @@ static void psci_sys_poweroff(void) invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); } +/* + * Detect the presence of a resident Trusted OS which may cause CPU_OFF to + * return DENIED (which would be fatal). + */ +static void __init psci_init_migrate(void) +{ + unsigned long cpuid; + int type, cpu; + + type = psci_ops.migrate_info_type(); + + if (type == PSCI_0_2_TOS_MP) { + pr_info("Trusted OS migration not required\n"); + return; + } + + if (type == PSCI_RET_NOT_SUPPORTED) { + pr_info("MIGRATE_INFO_TYPE not supported.\n"); + return; + } + + if (type != PSCI_0_2_TOS_UP_MIGRATE && + type != PSCI_0_2_TOS_UP_NO_MIGRATE) { + pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type); + return; + } + + cpuid = psci_migrate_info_up_cpu(); + if (cpuid & ~MPIDR_HWID_BITMASK) { + pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n", + cpuid); + return; + } + + cpu = get_logical_index(cpuid); + resident_cpu = cpu >= 0 ? cpu : -1; + + pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid); +} + static void __init psci_0_2_set_functions(void) { pr_info("Using standard PSCI v0.2 function IDs\n"); @@ -290,11 +317,8 @@ static void __init psci_0_2_set_functions(void) 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; @@ -307,32 +331,26 @@ static void __init psci_0_2_set_functions(void) */ static int __init psci_probe(void) { - int ver = psci_get_version(); - - if (ver == PSCI_RET_NOT_SUPPORTED) { - /* - * PSCI versions >=0.2 mandates implementation of - * PSCI_VERSION. - */ - pr_err("PSCI firmware does not comply with the v0.2 spec.\n"); - return -EOPNOTSUPP; - } 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) { - pr_err("Conflicting PSCI version detected.\n"); - return -EINVAL; - } + u32 ver = psci_get_version(); + + 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) { + pr_err("Conflicting PSCI version detected.\n"); + return -EINVAL; } psci_0_2_set_functions(); + psci_init_migrate(); + return 0; } +typedef int (*psci_initcall_t)(const struct device_node *); + /* * PSCI init function for PSCI versions >=0.2 * @@ -421,6 +439,7 @@ int __init psci_dt_init(void) return init_fn(np); } +#ifdef CONFIG_ACPI /* * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's * explicitly clarified in SBBR @@ -441,10 +460,11 @@ int __init psci_acpi_init(void) return psci_probe(); } +#endif #ifdef CONFIG_SMP -static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu) +static int __init cpu_psci_cpu_init(unsigned int cpu) { return 0; } @@ -469,11 +489,21 @@ static int cpu_psci_cpu_boot(unsigned int cpu) } #ifdef CONFIG_HOTPLUG_CPU +static bool psci_tos_resident_on(int cpu) +{ + return cpu == resident_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; + + /* Trusted OS will deny CPU_OFF */ + if (psci_tos_resident_on(cpu)) + return -EPERM; + return 0; } @@ -484,9 +514,8 @@ static void cpu_psci_cpu_die(unsigned int cpu) * 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, - }; + u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN << + PSCI_0_2_POWER_STATE_TYPE_SHIFT; ret = psci_ops.cpu_off(state); @@ -498,7 +527,7 @@ static int cpu_psci_cpu_kill(unsigned int cpu) int err, i; if (!psci_ops.affinity_info) - return 1; + return 0; /* * cpu_kill could race with cpu_die and we can * potentially end up declaring this cpu undead @@ -509,7 +538,7 @@ static int cpu_psci_cpu_kill(unsigned int cpu) 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; + return 0; } msleep(10); @@ -518,15 +547,14 @@ static int cpu_psci_cpu_kill(unsigned int cpu) pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n", cpu, err); - /* Make op_cpu_kill() fail. */ - return 0; + return -ETIMEDOUT; } #endif #endif static int psci_suspend_finisher(unsigned long index) { - struct psci_power_state *state = __this_cpu_read(psci_power_state); + u32 *state = __this_cpu_read(psci_power_state); return psci_ops.cpu_suspend(state[index - 1], virt_to_phys(cpu_resume)); @@ -535,7 +563,7 @@ static int psci_suspend_finisher(unsigned long index) static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index) { int ret; - struct psci_power_state *state = __this_cpu_read(psci_power_state); + u32 *state = __this_cpu_read(psci_power_state); /* * idle state index 0 corresponds to wfi, should never be called * from the cpu_suspend operations @@ -543,10 +571,10 @@ static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index) if (WARN_ON_ONCE(!index)) return -EINVAL; - if (state[index - 1].type == PSCI_POWER_STATE_TYPE_STANDBY) + if (!psci_power_state_loses_context(state[index - 1])) ret = psci_ops.cpu_suspend(state[index - 1], 0); else - ret = __cpu_suspend(index, psci_suspend_finisher); + ret = cpu_suspend(index, psci_suspend_finisher); return ret; } |