[PATCH V2 3/3] ARM: tegra114: cpuidle: add powered-down state
From: Daniel Lezcano <hidden>
Date: 2013-06-04 21:40:51
Also in:
linux-tegra
On 06/04/2013 12:48 PM, Joseph Lo wrote:
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 <redacted>
I would like to understand why there is a WARN with the CPUIDLE_FLAG_TIMER_STOP flag set before queuing this patch and ensure it is not the tree hiding the forest. Thanks -- Daniel
quoted hunk ↗ jump to hunk
--- V2: * remove some redundant code of memory barrier * remove the function declaration by rearranging the coding sequence --- arch/arm/mach-tegra/cpuidle-tegra114.c | 51 +++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-)diff --git a/arch/arm/mach-tegra/cpuidle-tegra114.c b/arch/arm/mach-tegra/cpuidle-tegra114.c index 1d1c602..e0b8730 100644 --- a/arch/arm/mach-tegra/cpuidle-tegra114.c +++ b/arch/arm/mach-tegra/cpuidle-tegra114.c@@ -17,15 +17,64 @@ #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 +#define TEGRA114_MAX_STATES 2 +#else +#define TEGRA114_MAX_STATES 1 +#endif + +#ifdef CONFIG_PM_SLEEP +static int tegra114_idle_power_down(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + local_fiq_disable(); + + tegra_set_cpu_in_lp2(); + cpu_pm_enter(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + + 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(); + + local_fiq_enable(); + + return index; +} +#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 }, };
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