summaryrefslogtreecommitdiff
path: root/drivers/cpuidle
diff options
context:
space:
mode:
authorOlof Johansson <olof@lixom.net>2015-02-06 01:07:33 -0800
committerOlof Johansson <olof@lixom.net>2015-02-06 01:07:33 -0800
commit6f4554bdff6870c9e0f0b152bbec71d7a0f366f1 (patch)
treea3620f79a76f6f848f0f8be8b0d98d37a533acc0 /drivers/cpuidle
parent68a028f856f7ad2482a617ae02518634bae16809 (diff)
parent712eddf70225ab5ae65e946e22d2dfe6b93e8dd1 (diff)
Merge tag 'samsung-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into next/drivers
Merge "Samsung CPUIdle updates for v3.20" from Kukjin Kim: - adds coupled cpuidle support for exynos4210 : fix for Exynos platform PM code preparing it for the coupled cpuidle support and adds coupled cpuidle AFTR mode on exynos4210 Note this is mostrly based on earlier cpuidle-exynos4210 driver from Daniel Lezcano and Bart updated. * tag 'samsung-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung: cpuidle: exynos: add coupled cpuidle support for exynos4210 ARM: EXYNOS: apply S5P_CENTRAL_SEQ_OPTION fix only when necessary Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r--drivers/cpuidle/Kconfig.arm1
-rw-r--r--drivers/cpuidle/cpuidle-exynos.c76
2 files changed, 72 insertions, 5 deletions
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index 8c16ab20fb15..8e07c9419153 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -55,6 +55,7 @@ config ARM_AT91_CPUIDLE
config ARM_EXYNOS_CPUIDLE
bool "Cpu Idle Driver for the Exynos processors"
depends on ARCH_EXYNOS
+ select ARCH_NEEDS_CPU_IDLE_COUPLED if SMP
help
Select this to enable cpuidle for Exynos processors
diff --git a/drivers/cpuidle/cpuidle-exynos.c b/drivers/cpuidle/cpuidle-exynos.c
index 4003a3160865..26f5f29fdb03 100644
--- a/drivers/cpuidle/cpuidle-exynos.c
+++ b/drivers/cpuidle/cpuidle-exynos.c
@@ -1,8 +1,11 @@
-/* linux/arch/arm/mach-exynos/cpuidle.c
- *
- * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+/*
+ * Copyright (c) 2011-2014 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
+ * Coupled cpuidle support based on the work of:
+ * Colin Cross <ccross@android.com>
+ * Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
@@ -13,13 +16,49 @@
#include <linux/export.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/platform_data/cpuidle-exynos.h>
#include <asm/proc-fns.h>
#include <asm/suspend.h>
#include <asm/cpuidle.h>
+static atomic_t exynos_idle_barrier;
+
+static struct cpuidle_exynos_data *exynos_cpuidle_pdata;
static void (*exynos_enter_aftr)(void);
+static int exynos_enter_coupled_lowpower(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ int ret;
+
+ exynos_cpuidle_pdata->pre_enter_aftr();
+
+ /*
+ * Waiting all cpus to reach this point at the same moment
+ */
+ cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
+
+ /*
+ * Both cpus will reach this point at the same time
+ */
+ ret = dev->cpu ? exynos_cpuidle_pdata->cpu1_powerdown()
+ : exynos_cpuidle_pdata->cpu0_enter_aftr();
+ if (ret)
+ index = ret;
+
+ /*
+ * Waiting all cpus to finish the power sequence before going further
+ */
+ cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
+
+ exynos_cpuidle_pdata->post_enter_aftr();
+
+ return index;
+}
+
static int exynos_enter_lowpower(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
@@ -55,13 +94,40 @@ static struct cpuidle_driver exynos_idle_driver = {
.safe_state_index = 0,
};
+static struct cpuidle_driver exynos_coupled_idle_driver = {
+ .name = "exynos_coupled_idle",
+ .owner = THIS_MODULE,
+ .states = {
+ [0] = ARM_CPUIDLE_WFI_STATE,
+ [1] = {
+ .enter = exynos_enter_coupled_lowpower,
+ .exit_latency = 5000,
+ .target_residency = 10000,
+ .flags = CPUIDLE_FLAG_COUPLED |
+ CPUIDLE_FLAG_TIMER_STOP,
+ .name = "C1",
+ .desc = "ARM power down",
+ },
+ },
+ .state_count = 2,
+ .safe_state_index = 0,
+};
+
static int exynos_cpuidle_probe(struct platform_device *pdev)
{
int ret;
- exynos_enter_aftr = (void *)(pdev->dev.platform_data);
+ if (of_machine_is_compatible("samsung,exynos4210")) {
+ exynos_cpuidle_pdata = pdev->dev.platform_data;
+
+ ret = cpuidle_register(&exynos_coupled_idle_driver,
+ cpu_possible_mask);
+ } else {
+ exynos_enter_aftr = (void *)(pdev->dev.platform_data);
+
+ ret = cpuidle_register(&exynos_idle_driver, NULL);
+ }
- ret = cpuidle_register(&exynos_idle_driver, NULL);
if (ret) {
dev_err(&pdev->dev, "failed to register cpuidle driver\n");
return ret;