[PATCH v2] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

From: Tomeu Vizoso
Date: Mon May 18 2015 - 05:40:31 EST


This callback is expected to do the same as enter() only that won't
re-enable interrupts on exit.

It will be called when the system goes to suspend-to-idle and will
reduce power usage because CPUs won't be awaken for unnecessary IRQs.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

---

v2: * Disable FIQs also when suspending-to-idle
---
arch/arm/mach-tegra/cpuidle-tegra114.c | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/arch/arm/mach-tegra/cpuidle-tegra114.c b/arch/arm/mach-tegra/cpuidle-tegra114.c
index 155807f..e7c4359 100644
--- a/arch/arm/mach-tegra/cpuidle-tegra114.c
+++ b/arch/arm/mach-tegra/cpuidle-tegra114.c
@@ -35,32 +35,42 @@
#endif

#ifdef CONFIG_PM_SLEEP
-static int tegra114_idle_power_down(struct cpuidle_device *dev,
- struct cpuidle_driver *drv,
- int index)
+static void tegra114_idle_power_down(void)
{
local_fiq_disable();

tegra_set_cpu_in_lp2();
cpu_pm_enter();

- tick_broadcast_enter();
-
call_firmware_op(prepare_idle);

/* Do suspend by ourselves if the firmware does not implement it */
if (call_firmware_op(do_idle, 0) == -ENOSYS)
cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);

- tick_broadcast_exit();
-
cpu_pm_exit();
tegra_clear_cpu_in_lp2();

local_fiq_enable();
+}
+
+static int tegra114_idle_enter(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ tick_broadcast_enter();
+ tegra114_idle_power_down();
+ tick_broadcast_exit();

return index;
}
+
+static void tegra114_idle_enter_freeze(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ tegra114_idle_power_down();
+}
#endif

static struct cpuidle_driver tegra_idle_driver = {
@@ -71,7 +81,8 @@ static struct cpuidle_driver tegra_idle_driver = {
[0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
#ifdef CONFIG_PM_SLEEP
[1] = {
- .enter = tegra114_idle_power_down,
+ .enter = tegra114_idle_enter,
+ .enter_freeze = tegra114_idle_enter_freeze,
.exit_latency = 500,
.target_residency = 1000,
.power_usage = 0,
--
2.4.0

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