This patch implement cpuidle_ops using psci, the code is stolen from arm64. Now we can use cpuidle-arm.c for both arm and arm64.
Signed-off-by: Jisheng Zhang <[email protected]> --- arch/arm/kernel/psci.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c index 7f6ff02..7bf744d 100644 --- a/arch/arm/kernel/psci.c +++ b/arch/arm/kernel/psci.c @@ -13,16 +13,132 @@ * Author: Will Deacon <[email protected]> */ +#include <linux/cpuidle.h> #include <linux/init.h> #include <linux/smp.h> #include <linux/of.h> #include <linux/delay.h> #include <linux/psci.h> +#include <linux/slab.h> #include <uapi/linux/psci.h> +#include <asm/cpuidle.h> #include <asm/psci.h> #include <asm/smp_plat.h> +#include <asm/suspend.h> + +#ifdef CONFIG_CPU_IDLE +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); +} + +static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state); + +static int __init cpu_psci_cpu_init_idle(struct device_node *cpu_node, + int cpu) +{ + int i, ret, count = 0; + u32 *psci_states; + struct device_node *state_node; + + /* + * 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; + + /* 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++) { + u32 state; + + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); + + ret = of_property_read_u32(state_node, + "arm,psci-suspend-param", + &state); + if (ret) { + pr_warn(" * %s missing arm,psci-suspend-param property\n", + state_node->full_name); + of_node_put(state_node); + goto free_mem; + } + + of_node_put(state_node); + pr_warn("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; + return 0; + +free_mem: + kfree(psci_states); + 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], + virt_to_phys(cpu_resume)); +} + +static int cpu_psci_cpu_suspend(int cpu, unsigned long index) +{ + 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); + else + ret = cpu_suspend(index, psci_suspend_finisher); + + return ret; +} + +static struct cpuidle_ops psci_cpuidle_ops __initdata = { + .suspend = cpu_psci_cpu_suspend, + .init = cpu_psci_cpu_init_idle, +}; +CPUIDLE_METHOD_OF_DECLARE(psci_idle, "psci", &psci_cpuidle_ops); +#endif /* * psci_smp assumes that the following is true about PSCI: -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
