diff options
Diffstat (limited to 'arch/arm64/kernel/psci.c')
| -rw-r--r-- | arch/arm64/kernel/psci.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index ea4828a4aa96..0e32ab453e5b 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -15,15 +15,18 @@ #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 <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> #define PSCI_POWER_STATE_TYPE_STANDBY 0 #define PSCI_POWER_STATE_TYPE_POWER_DOWN 1 @@ -54,6 +57,8 @@ enum psci_function { PSCI_FN_MAX, }; +static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); + static u32 psci_function_id[PSCI_FN_MAX]; #define PSCI_RET_SUCCESS 0 @@ -94,6 +99,17 @@ static u32 psci_power_state_pack(struct psci_power_state state) << PSCI_POWER_STATE_AFFL_SHIFT); } +static void psci_power_state_unpack(u32 power_state, + struct psci_power_state *state) +{ + state->id = (power_state >> PSCI_POWER_STATE_ID_SHIFT) + & PSCI_POWER_STATE_ID_MASK; + state->type = (power_state >> PSCI_POWER_STATE_TYPE_SHIFT) + & PSCI_POWER_STATE_TYPE_MASK; + state->affinity_level = (power_state >> PSCI_POWER_STATE_AFFL_SHIFT) + & PSCI_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. @@ -176,6 +192,77 @@ static const struct of_device_id psci_of_match[] __initconst = { {}, }; +int __init psci_dt_register_idle_states(struct cpuidle_driver *drv, + struct device_node *state_nodes[]) +{ + int cpu, i; + struct psci_power_state *psci_states; + const struct cpu_operations *cpu_ops_ptr; + + if (!state_nodes) + return -EINVAL; + /* + * This is belt-and-braces: make sure that if the idle + * specified protocol is psci, the cpu_ops have been + * initialized to psci operations. Anything else is + * a recipe for mayhem. + */ + for_each_cpu(cpu, drv->cpumask) { + cpu_ops_ptr = cpu_ops[cpu]; + if (WARN_ON(!cpu_ops_ptr || strcmp(cpu_ops_ptr->name, "psci"))) + return -EOPNOTSUPP; + } + + psci_states = kcalloc(drv->state_count, sizeof(*psci_states), + GFP_KERNEL); + + if (!psci_states) { + pr_warn("psci idle state allocation failed\n"); + return -ENOMEM; + } + + for_each_cpu(cpu, drv->cpumask) { + if (per_cpu(psci_power_state, cpu)) { + pr_warn("idle states already initialized on cpu %u\n", + cpu); + continue; + } + per_cpu(psci_power_state, cpu) = psci_states; + } + + + for (i = 0; i < drv->state_count; i++) { + u32 psci_power_state; + + if (!state_nodes[i]) { + /* + * An index with a missing node pointer falls back to + * simple STANDBYWFI + */ + psci_states[i].type = PSCI_POWER_STATE_TYPE_STANDBY; + continue; + } + + if (of_property_read_u32(state_nodes[i], "entry-method-param", + &psci_power_state)) { + pr_warn(" * %s missing entry-method-param property\n", + state_nodes[i]->full_name); + /* + * If entry-method-param property is missing, fall + * back to STANDBYWFI state + */ + psci_states[i].type = PSCI_POWER_STATE_TYPE_STANDBY; + continue; + } + + pr_debug("psci-power-state %#x index %u\n", + psci_power_state, i); + psci_power_state_unpack(psci_power_state, &psci_states[i]); + } + + return 0; +} + void __init psci_init(void) { struct device_node *np; @@ -279,6 +366,18 @@ static void cpu_psci_cpu_die(unsigned int cpu) } #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", .cpu_init = cpu_psci_cpu_init, @@ -288,6 +387,9 @@ const struct cpu_operations cpu_psci_ops = { .cpu_disable = cpu_psci_cpu_disable, .cpu_die = cpu_psci_cpu_die, #endif +#ifdef CONFIG_ARM64_CPU_SUSPEND + .cpu_suspend = cpu_psci_cpu_suspend, +#endif }; #endif |