Current PSCI code handles idle state entry through the psci_cpu_suspend_enter() API, that takes an idle state index as a parameter and convert the index into a previously initialized power_state parameter before calling the PSCI.CPU_SUSPEND() with it.
This is unwieldly, since it forces the PSCI firmware layer to keep track of power_state parameter for every idle state so that the index->power_state conversion can be made in the PSCI firmware layer instead of the CPUidle driver implementations. Move the power_state handling out of drivers/firmware/psci into the respective ACPI/DT PSCI CPUidle backends and convert the psci_cpu_suspend_enter() API to get the power_state parameter as input, which makes it closer to its firmware interface PSCI.CPU_SUSPEND() API. A notable side effect is that the PSCI ACPI/DT CPUidle backends now can directly handle (and if needed update) power_state parameters before handing them over to the PSCI firmware interface to trigger PSCI.CPU_SUSPEND() calls. Signed-off-by: Lorenzo Pieralisi <[email protected]> Cc: Will Deacon <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: Sudeep Holla <[email protected]> Cc: Daniel Lezcano <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Mark Rutland <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> --- arch/arm64/kernel/cpuidle.c | 47 +++++++++- drivers/cpuidle/cpuidle-psci.c | 87 +++++++++++++++++- drivers/firmware/psci/psci.c | 158 ++------------------------------- include/linux/cpuidle.h | 17 +++- include/linux/psci.h | 4 +- 5 files changed, 153 insertions(+), 160 deletions(-) diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c index 4bcd1bca0dfc..e4d6af2fdec7 100644 --- a/arch/arm64/kernel/cpuidle.c +++ b/arch/arm64/kernel/cpuidle.c @@ -47,6 +47,44 @@ int arm_cpuidle_suspend(int index) #define ARM64_LPI_IS_RETENTION_STATE(arch_flags) (!(arch_flags)) +static int psci_acpi_cpu_init_idle(unsigned int cpu) +{ + int i, count; + struct acpi_lpi_state *lpi; + struct acpi_processor *pr = per_cpu(processors, cpu); + + /* + * If the PSCI cpu_suspend function hook has not been initialized + * idle states must not be enabled, so bail out + */ + if (!psci_ops.cpu_suspend) + return -EOPNOTSUPP; + + if (unlikely(!pr || !pr->flags.has_lpi)) + return -EINVAL; + + count = pr->power.count - 1; + if (count <= 0) + return -ENODEV; + + for (i = 0; i < count; i++) { + u32 state; + + lpi = &pr->power.lpi_states[i + 1]; + /* + * Only bits[31:0] represent a PSCI power_state while + * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification + */ + state = lpi->address; + if (!psci_power_state_is_valid(state)) { + pr_warn("Invalid PSCI power state %#x\n", state); + return -EINVAL; + } + } + + return 0; +} + int acpi_processor_ffh_lpi_probe(unsigned int cpu) { return psci_acpi_cpu_init_idle(cpu); @@ -54,10 +92,13 @@ int acpi_processor_ffh_lpi_probe(unsigned int cpu) int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) { + u32 state = lpi->address; + if (ARM64_LPI_IS_RETENTION_STATE(lpi->arch_flags)) - return CPU_PM_CPU_IDLE_ENTER_RETENTION(psci_cpu_suspend_enter, - lpi->index); + return CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(psci_cpu_suspend_enter, + lpi->index, state); else - return CPU_PM_CPU_IDLE_ENTER(psci_cpu_suspend_enter, lpi->index); + return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, + lpi->index, state); } #endif diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c index bdf02600e4e2..7485b3abe372 100644 --- a/drivers/cpuidle/cpuidle-psci.c +++ b/drivers/cpuidle/cpuidle-psci.c @@ -21,10 +21,15 @@ #include "dt_idle_states.h" +static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state); + static int psci_enter_idle_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, int idx) { - return CPU_PM_CPU_IDLE_ENTER(psci_cpu_suspend_enter, idx); + u32 *state = __this_cpu_read(psci_power_state); + + return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, + idx, state[idx - 1]); } static struct cpuidle_driver psci_idle_driver __initdata = { @@ -50,6 +55,86 @@ static const struct of_device_id psci_idle_state_match[] __initconst = { { }, }; +static int __init psci_dt_parse_state_node(struct device_node *np, u32 *state) +{ + int err = of_property_read_u32(np, "arm,psci-suspend-param", state); + + if (err) { + pr_warn("%pOF missing arm,psci-suspend-param property\n", np); + return err; + } + + if (!psci_power_state_is_valid(*state)) { + pr_warn("Invalid PSCI power state %#x\n", *state); + return -EINVAL; + } + + return 0; +} + +static int __init psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) +{ + int i, ret = 0, count = 0; + u32 *psci_states; + struct device_node *state_node; + + /* Count idle states */ + while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states", + count))) { + count++; + of_node_put(state_node); + } + + if (!count) + return -ENODEV; + + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); + if (!psci_states) + return -ENOMEM; + + for (i = 0; i < count; i++) { + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); + ret = psci_dt_parse_state_node(state_node, &psci_states[i]); + of_node_put(state_node); + + if (ret) + goto free_mem; + + pr_debug("psci-power-state %#x index %d\n", psci_states[i], i); + } + + /* Idle states parsed correctly, initialize per-cpu pointer */ + per_cpu(psci_power_state, cpu) = psci_states; + return 0; + +free_mem: + kfree(psci_states); + return ret; +} + +static __init int psci_cpu_init_idle(unsigned int cpu) +{ + struct device_node *cpu_node; + int ret; + + /* + * If the PSCI cpu_suspend function hook has not been initialized + * idle states must not be enabled, so bail out + */ + if (!psci_ops.cpu_suspend) + return -EOPNOTSUPP; + + cpu_node = of_get_cpu_node(cpu, NULL); + if (!cpu_node) + return -ENODEV; + + ret = psci_dt_cpu_init_idle(cpu_node, cpu); + + of_node_put(cpu_node); + + return ret; +} + static int __init psci_idle_init_cpu(int cpu) { struct cpuidle_driver *drv; diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index bae734d13a52..84f4ff351c62 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -103,7 +103,7 @@ static inline bool psci_power_state_loses_context(u32 state) return state & mask; } -static inline bool psci_power_state_is_valid(u32 state) +bool psci_power_state_is_valid(u32 state) { const u32 valid_mask = psci_has_ext_power_state() ? PSCI_1_0_EXT_POWER_STATE_MASK : @@ -277,167 +277,25 @@ static int __init psci_features(u32 psci_func_id) } #ifdef CONFIG_CPU_IDLE -static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state); - -static int psci_dt_parse_state_node(struct device_node *np, u32 *state) +static int psci_suspend_finisher(unsigned long state) { - int err = of_property_read_u32(np, "arm,psci-suspend-param", state); + u32 power_state = state; - if (err) { - pr_warn("%pOF missing arm,psci-suspend-param property\n", np); - return err; - } - - if (!psci_power_state_is_valid(*state)) { - pr_warn("Invalid PSCI power state %#x\n", *state); - return -EINVAL; - } - - return 0; + return psci_ops.cpu_suspend(power_state, __pa_symbol(cpu_resume)); } -static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) -{ - int i, ret = 0, count = 0; - u32 *psci_states; - struct device_node *state_node; - - /* Count idle states */ - while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states", - count))) { - count++; - of_node_put(state_node); - } - - if (!count) - return -ENODEV; - - psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); - if (!psci_states) - return -ENOMEM; - - for (i = 0; i < count; i++) { - state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); - ret = psci_dt_parse_state_node(state_node, &psci_states[i]); - of_node_put(state_node); - - if (ret) - goto free_mem; - - pr_debug("psci-power-state %#x index %d\n", psci_states[i], i); - } - - /* Idle states parsed correctly, initialize per-cpu pointer */ - per_cpu(psci_power_state, cpu) = psci_states; - return 0; - -free_mem: - kfree(psci_states); - return ret; -} - -#ifdef CONFIG_ACPI -#include <acpi/processor.h> - -static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) -{ - int i, count; - u32 *psci_states; - struct acpi_lpi_state *lpi; - struct acpi_processor *pr = per_cpu(processors, cpu); - - if (unlikely(!pr || !pr->flags.has_lpi)) - return -EINVAL; - - count = pr->power.count - 1; - if (count <= 0) - return -ENODEV; - - psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); - if (!psci_states) - return -ENOMEM; - - for (i = 0; i < count; i++) { - u32 state; - - lpi = &pr->power.lpi_states[i + 1]; - /* - * Only bits[31:0] represent a PSCI power_state while - * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification - */ - state = lpi->address; - if (!psci_power_state_is_valid(state)) { - pr_warn("Invalid PSCI power state %#x\n", state); - kfree(psci_states); - return -EINVAL; - } - psci_states[i] = state; - } - /* Idle states parsed correctly, initialize per-cpu pointer */ - per_cpu(psci_power_state, cpu) = psci_states; - return 0; -} -#else -static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) -{ - return -EINVAL; -} -#endif - -int psci_cpu_init_idle(unsigned int cpu) -{ - struct device_node *cpu_node; - int ret; - - /* - * If the PSCI cpu_suspend function hook has not been initialized - * idle states must not be enabled, so bail out - */ - if (!psci_ops.cpu_suspend) - return -EOPNOTSUPP; - - if (!acpi_disabled) - return psci_acpi_cpu_init_idle(cpu); - - cpu_node = of_get_cpu_node(cpu, NULL); - if (!cpu_node) - return -ENODEV; - - ret = psci_dt_cpu_init_idle(cpu_node, cpu); - - of_node_put(cpu_node); - - return ret; -} - -static int psci_suspend_finisher(unsigned long index) -{ - u32 *state = __this_cpu_read(psci_power_state); - - return psci_ops.cpu_suspend(state[index - 1], - __pa_symbol(cpu_resume)); -} - -int psci_cpu_suspend_enter(unsigned long index) +int psci_cpu_suspend_enter(u32 state) { int ret; - u32 *state = __this_cpu_read(psci_power_state); - /* - * idle state index 0 corresponds to wfi, should never be called - * from the cpu_suspend operations - */ - if (WARN_ON_ONCE(!index)) - return -EINVAL; - if (!psci_power_state_loses_context(state[index - 1])) - ret = psci_ops.cpu_suspend(state[index - 1], 0); + if (!psci_power_state_loses_context(state)) + ret = psci_ops.cpu_suspend(state, 0); else - ret = cpu_suspend(index, psci_suspend_finisher); + ret = cpu_suspend(state, psci_suspend_finisher); return ret; } #endif -#endif static int psci_system_suspend(unsigned long unused) { diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index bb9a0db89f1a..12ae4b87494e 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -256,7 +256,10 @@ static inline int cpuidle_register_governor(struct cpuidle_governor *gov) {return 0;} #endif -#define __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, is_retention) \ +#define __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, \ + idx, \ + state, \ + is_retention) \ ({ \ int __ret = 0; \ \ @@ -268,7 +271,7 @@ static inline int cpuidle_register_governor(struct cpuidle_governor *gov) if (!is_retention) \ __ret = cpu_pm_enter(); \ if (!__ret) { \ - __ret = low_level_idle_enter(idx); \ + __ret = low_level_idle_enter(state); \ if (!is_retention) \ cpu_pm_exit(); \ } \ @@ -277,9 +280,15 @@ static inline int cpuidle_register_governor(struct cpuidle_governor *gov) }) #define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \ - __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, 0) + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, idx, 0) #define CPU_PM_CPU_IDLE_ENTER_RETENTION(low_level_idle_enter, idx) \ - __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, 1) + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, idx, 1) + +#define CPU_PM_CPU_IDLE_ENTER_PARAM(low_level_idle_enter, idx, state) \ + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, state, 0) + +#define CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(low_level_idle_enter, idx, state) \ + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, state, 1) #endif /* _LINUX_CPUIDLE_H */ diff --git a/include/linux/psci.h b/include/linux/psci.h index a8a15613c157..e2bacc6fd2f2 100644 --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -15,8 +15,8 @@ bool psci_tos_resident_on(int cpu); -int psci_cpu_init_idle(unsigned int cpu); -int psci_cpu_suspend_enter(unsigned long index); +int psci_cpu_suspend_enter(u32 state); +bool psci_power_state_is_valid(u32 state); enum psci_conduit { PSCI_CONDUIT_NONE, -- 2.21.0
