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>

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;