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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-04 01:10:15 +0400
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-04 01:10:15 +0400
commit97b80e685ffae9a6dc946ab08ed32f1eafda97d7 (patch)
tree96baa368706662230b1aa98b3f83d8425aef46b8 /drivers
parent91ab377ba3ab202c40a0da402d6c2f1507a15355 (diff)
parent9051785f6928456db0692b8ca972778b9bf42099 (diff)
downloadlinux-97b80e685ffae9a6dc946ab08ed32f1eafda97d7.tar.xz
Merge branch 'pm-cpuidle'
* pm-cpuidle: PM / suspend: Always use deepest C-state in the "freeze" sleep state cpuidle / menu: move repeated correction factor check to init cpuidle / menu: Return (-1) if there are no suitable states cpuidle: Combine cpuidle_enabled() with cpuidle_select() ARM: clps711x: Add cpuidle driver
Diffstat (limited to 'drivers')
-rw-r--r--drivers/cpuidle/Kconfig.arm6
-rw-r--r--drivers/cpuidle/Makefile1
-rw-r--r--drivers/cpuidle/cpuidle-clps711x.c64
-rw-r--r--drivers/cpuidle/cpuidle.c55
-rw-r--r--drivers/cpuidle/governors/menu.c17
5 files changed, 122 insertions, 21 deletions
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index 97ccc31dbdd8..371e75d2348d 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -13,6 +13,12 @@ config ARM_BIG_LITTLE_CPUIDLE
define different C-states for little and big cores through the
multiple CPU idle drivers infrastructure.
+config ARM_CLPS711X_CPUIDLE
+ bool "CPU Idle Driver for CLPS711X processors"
+ depends on ARCH_CLPS711X || COMPILE_TEST
+ help
+ Select this to enable cpuidle on Cirrus Logic CLPS711X SOCs.
+
config ARM_HIGHBANK_CPUIDLE
bool "CPU Idle Driver for Calxeda processors"
depends on ARM_PSCI
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index f71ae1b373c5..534fff575823 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
##################################################################################
# ARM SoC drivers
obj-$(CONFIG_ARM_BIG_LITTLE_CPUIDLE) += cpuidle-big_little.o
+obj-$(CONFIG_ARM_CLPS711X_CPUIDLE) += cpuidle-clps711x.o
obj-$(CONFIG_ARM_HIGHBANK_CPUIDLE) += cpuidle-calxeda.o
obj-$(CONFIG_ARM_KIRKWOOD_CPUIDLE) += cpuidle-kirkwood.o
obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o
diff --git a/drivers/cpuidle/cpuidle-clps711x.c b/drivers/cpuidle/cpuidle-clps711x.c
new file mode 100644
index 000000000000..5243811daa6e
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-clps711x.c
@@ -0,0 +1,64 @@
+/*
+ * CLPS711X CPU idle driver
+ *
+ * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#define CLPS711X_CPUIDLE_NAME "clps711x-cpuidle"
+
+static void __iomem *clps711x_halt;
+
+static int clps711x_cpuidle_halt(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int index)
+{
+ writel(0xaa, clps711x_halt);
+
+ return index;
+}
+
+static struct cpuidle_driver clps711x_idle_driver = {
+ .name = CLPS711X_CPUIDLE_NAME,
+ .owner = THIS_MODULE,
+ .states[0] = {
+ .name = "HALT",
+ .desc = "CLPS711X HALT",
+ .enter = clps711x_cpuidle_halt,
+ .exit_latency = 1,
+ },
+ .state_count = 1,
+};
+
+static int __init clps711x_cpuidle_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ clps711x_halt = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(clps711x_halt))
+ return PTR_ERR(clps711x_halt);
+
+ return cpuidle_register(&clps711x_idle_driver, NULL);
+}
+
+static struct platform_driver clps711x_cpuidle_driver = {
+ .driver = {
+ .name = CLPS711X_CPUIDLE_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+module_platform_driver_probe(clps711x_cpuidle_driver, clps711x_cpuidle_probe);
+
+MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
+MODULE_DESCRIPTION("CLPS711X CPU idle driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 8236746e46bb..cb7019977c50 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -32,6 +32,7 @@ LIST_HEAD(cpuidle_detected_devices);
static int enabled_devices;
static int off __read_mostly;
static int initialized __read_mostly;
+static bool use_deepest_state __read_mostly;
int cpuidle_disabled(void)
{
@@ -65,23 +66,42 @@ int cpuidle_play_dead(void)
}
/**
- * cpuidle_enabled - check if the cpuidle framework is ready
- * @dev: cpuidle device for this cpu
- * @drv: cpuidle driver for this cpu
+ * cpuidle_use_deepest_state - Enable/disable the "deepest idle" mode.
+ * @enable: Whether enable or disable the feature.
+ *
+ * If the "deepest idle" mode is enabled, cpuidle will ignore the governor and
+ * always use the state with the greatest exit latency (out of the states that
+ * are not disabled).
*
- * Return 0 on success, otherwise:
- * -NODEV : the cpuidle framework is not available
- * -EBUSY : the cpuidle framework is not initialized
+ * This function can only be called after cpuidle_pause() to avoid races.
*/
-int cpuidle_enabled(struct cpuidle_driver *drv, struct cpuidle_device *dev)
+void cpuidle_use_deepest_state(bool enable)
{
- if (off || !initialized)
- return -ENODEV;
+ use_deepest_state = enable;
+}
- if (!drv || !dev || !dev->enabled)
- return -EBUSY;
+/**
+ * cpuidle_find_deepest_state - Find the state of the greatest exit latency.
+ * @drv: cpuidle driver for a given CPU.
+ * @dev: cpuidle device for a given CPU.
+ */
+static int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev)
+{
+ unsigned int latency_req = 0;
+ int i, ret = CPUIDLE_DRIVER_STATE_START - 1;
- return 0;
+ for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+ struct cpuidle_state *s = &drv->states[i];
+ struct cpuidle_state_usage *su = &dev->states_usage[i];
+
+ if (s->disabled || su->disable || s->exit_latency <= latency_req)
+ continue;
+
+ latency_req = s->exit_latency;
+ ret = i;
+ }
+ return ret;
}
/**
@@ -138,6 +158,15 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
*/
int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
+ if (off || !initialized)
+ return -ENODEV;
+
+ if (!drv || !dev || !dev->enabled)
+ return -EBUSY;
+
+ if (unlikely(use_deepest_state))
+ return cpuidle_find_deepest_state(drv, dev);
+
return cpuidle_curr_governor->select(drv, dev);
}
@@ -169,7 +198,7 @@ int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev,
*/
void cpuidle_reflect(struct cpuidle_device *dev, int index)
{
- if (cpuidle_curr_governor->reflect)
+ if (cpuidle_curr_governor->reflect && !unlikely(use_deepest_state))
cpuidle_curr_governor->reflect(dev, index);
}
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 71b523293354..c4f80c15a48d 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -296,7 +296,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
data->needs_update = 0;
}
- data->last_state_idx = 0;
+ data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1;
/* Special case when user has set very strict latency requirement */
if (unlikely(latency_req == 0))
@@ -311,13 +311,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
data->bucket = which_bucket(data->next_timer_us);
/*
- * if the correction factor is 0 (eg first time init or cpu hotplug
- * etc), we actually want to start out with a unity factor.
- */
- if (data->correction_factor[data->bucket] == 0)
- data->correction_factor[data->bucket] = RESOLUTION * DECAY;
-
- /*
* Force the result of multiplication to be 64 bits even if both
* operands are 32 bits.
* Make sure to round up for half microseconds.
@@ -466,9 +459,17 @@ static int menu_enable_device(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
{
struct menu_device *data = &per_cpu(menu_devices, dev->cpu);
+ int i;
memset(data, 0, sizeof(struct menu_device));
+ /*
+ * if the correction factor is 0 (eg first time init or cpu hotplug
+ * etc), we actually want to start out with a unity factor.
+ */
+ for(i = 0; i < BUCKETS; i++)
+ data->correction_factor[i] = RESOLUTION * DECAY;
+
return 0;
}