This supports CPU core power down on each CPU when CPU idle. When CPU go into this state, it saves it's context and needs a proper configuration in flow controller to power gate the CPU when CPU runs into WFI instruction. And the CPU also needs to set the IRQ as CPU power down idle wake up event in flow controller.
Signed-off-by: Joseph Lo <[email protected]> --- arch/arm/mach-tegra/cpuidle-tegra114.c | 62 +++++++++++++++++++++++++++++++++- 1 file changed, 61 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-tegra/cpuidle-tegra114.c b/arch/arm/mach-tegra/cpuidle-tegra114.c index 1d1c602..e7d21f5 100644 --- a/arch/arm/mach-tegra/cpuidle-tegra114.c +++ b/arch/arm/mach-tegra/cpuidle-tegra114.c @@ -17,19 +17,79 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/cpuidle.h> +#include <linux/cpu_pm.h> +#include <linux/clockchips.h> #include <asm/cpuidle.h> +#include <asm/suspend.h> +#include <asm/smp_plat.h> + +#include "pm.h" +#include "sleep.h" + +#ifdef CONFIG_PM_SLEEP +static int tegra114_idle_power_down(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index); +#define TEGRA114_MAX_STATES 2 +#else +#define TEGRA114_MAX_STATES 1 +#endif static struct cpuidle_driver tegra_idle_driver = { .name = "tegra_idle", .owner = THIS_MODULE, - .state_count = 1, + .state_count = TEGRA114_MAX_STATES, .states = { [0] = ARM_CPUIDLE_WFI_STATE_PWR(600), +#ifdef CONFIG_PM_SLEEP + [1] = { + .enter = tegra114_idle_power_down, + .exit_latency = 500, + .target_residency = 1000, + .power_usage = 0, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "powered-down", + .desc = "CPU power gated", + }, +#endif }, }; +#ifdef CONFIG_PM_SLEEP +static int tegra114_idle_power_down(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + u32 cpu = is_smp() ? cpu_logical_map(dev->cpu) : dev->cpu; + + local_fiq_disable(); + + tegra_set_cpu_in_lp2(cpu); + cpu_pm_enter(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + smp_wmb(); + + cpu_suspend(0, tegra30_sleep_cpu_secondary_finish); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); + + cpu_pm_exit(); + tegra_clear_cpu_in_lp2(cpu); + + local_fiq_enable(); + + smp_rmb(); + + return index; +} +#endif + int __init tegra114_cpuidle_init(void) { +#ifdef CONFIG_PM_SLEEP + tegra_tear_down_cpu = tegra30_tear_down_cpu; +#endif return cpuidle_register(&tegra_idle_driver, NULL); } -- 1.8.3 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
