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authorJon Medhurst <tixy@linaro.org>2013-05-09 14:07:03 +0100
committerJon Medhurst <tixy@linaro.org>2013-05-09 14:07:03 +0100
commitc5b970dd2f809ce3675902f672a1d676aed43c7a (patch)
tree89311b14d29ab1d8ea2966e22941ac5b2214db25 /drivers/cpuidle/arm_big_little.c
parent3bc528d32c5c98a496c3473353e701a6e23c0cb3 (diff)
parent892404cc9460bdc9156ec0ca3ac27c6f20539213 (diff)
downloadvexpress-lsk-c5b970dd2f809ce3675902f672a1d676aed43c7a.tar.gz
Merge branch 'tracking-armlt-tc2-pm' into lsk-3.9-vexpress
Conflicts: arch/arm/mach-vexpress/Kconfig arch/arm/mach-vexpress/Makefile
Diffstat (limited to 'drivers/cpuidle/arm_big_little.c')
-rw-r--r--drivers/cpuidle/arm_big_little.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/drivers/cpuidle/arm_big_little.c b/drivers/cpuidle/arm_big_little.c
new file mode 100644
index 00000000000..a430800d4a7
--- /dev/null
+++ b/drivers/cpuidle/arm_big_little.c
@@ -0,0 +1,183 @@
+/*
+ * big.LITTLE CPU idle driver.
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
+ *
+ * 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.
+ */
+
+#include <linux/arm-cci.h>
+#include <linux/bitmap.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/clockchips.h>
+#include <linux/debugfs.h>
+#include <linux/hrtimer.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/tick.h>
+#include <linux/vexpress.h>
+#include <asm/mcpm.h>
+#include <asm/cpuidle.h>
+#include <asm/cputype.h>
+#include <asm/idmap.h>
+#include <asm/proc-fns.h>
+#include <asm/suspend.h>
+#include <linux/of.h>
+
+static int bl_cpuidle_simple_enter(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int index)
+{
+ ktime_t time_start, time_end;
+ s64 diff;
+
+ time_start = ktime_get();
+
+ cpu_do_idle();
+
+ time_end = ktime_get();
+
+ local_irq_enable();
+
+ diff = ktime_to_us(ktime_sub(time_end, time_start));
+ if (diff > INT_MAX)
+ diff = INT_MAX;
+
+ dev->last_residency = (int) diff;
+
+ return index;
+}
+
+static int bl_enter_powerdown(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int idx);
+
+static struct cpuidle_state bl_cpuidle_set[] __initdata = {
+ [0] = {
+ .enter = bl_cpuidle_simple_enter,
+ .exit_latency = 1,
+ .target_residency = 1,
+ .power_usage = UINT_MAX,
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .name = "WFI",
+ .desc = "ARM WFI",
+ },
+ [1] = {
+ .enter = bl_enter_powerdown,
+ .exit_latency = 300,
+ .target_residency = 1000,
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .name = "C1",
+ .desc = "ARM power down",
+ },
+};
+
+struct cpuidle_driver bl_idle_driver = {
+ .name = "bl_idle",
+ .owner = THIS_MODULE,
+ .safe_state_index = 0
+};
+
+static DEFINE_PER_CPU(struct cpuidle_device, bl_idle_dev);
+
+static int notrace bl_powerdown_finisher(unsigned long arg)
+{
+ unsigned int mpidr = read_cpuid_mpidr();
+ unsigned int cluster = (mpidr >> 8) & 0xf;
+ unsigned int cpu = mpidr & 0xf;
+
+ mcpm_set_entry_vector(cpu, cluster, cpu_resume);
+ mcpm_cpu_suspend(0); /* 0 should be replaced with better value here */
+ return 1;
+}
+
+/*
+ * bl_enter_powerdown - Programs CPU to enter the specified state
+ * @dev: cpuidle device
+ * @drv: The target state to be programmed
+ * @idx: state index
+ *
+ * Called from the CPUidle framework to program the device to the
+ * specified target state selected by the governor.
+ */
+static int bl_enter_powerdown(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int idx)
+{
+ struct timespec ts_preidle, ts_postidle, ts_idle;
+ int ret;
+
+ /* Used to keep track of the total time in idle */
+ getnstimeofday(&ts_preidle);
+
+ BUG_ON(!irqs_disabled());
+
+ cpu_pm_enter();
+
+ clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu);
+
+ ret = cpu_suspend((unsigned long) dev, bl_powerdown_finisher);
+ if (ret)
+ BUG();
+
+ mcpm_cpu_powered_up();
+
+ clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
+
+ cpu_pm_exit();
+
+ getnstimeofday(&ts_postidle);
+ local_irq_enable();
+ ts_idle = timespec_sub(ts_postidle, ts_preidle);
+
+ dev->last_residency = ts_idle.tv_nsec / NSEC_PER_USEC +
+ ts_idle.tv_sec * USEC_PER_SEC;
+ return idx;
+}
+
+/*
+ * bl_idle_init
+ *
+ * Registers the bl specific cpuidle driver with the cpuidle
+ * framework with the valid set of states.
+ */
+int __init bl_idle_init(void)
+{
+ struct cpuidle_device *dev;
+ int i, cpu_id;
+ struct cpuidle_driver *drv = &bl_idle_driver;
+
+ if (!of_find_compatible_node(NULL, NULL, "arm,generic")) {
+ pr_info("%s: No compatible node found\n", __func__);
+ return -ENODEV;
+ }
+
+ drv->state_count = (sizeof(bl_cpuidle_set) /
+ sizeof(struct cpuidle_state));
+
+ for (i = 0; i < drv->state_count; i++) {
+ memcpy(&drv->states[i], &bl_cpuidle_set[i],
+ sizeof(struct cpuidle_state));
+ }
+
+ cpuidle_register_driver(drv);
+
+ for_each_cpu(cpu_id, cpu_online_mask) {
+ pr_err("CPUidle for CPU%d registered\n", cpu_id);
+ dev = &per_cpu(bl_idle_dev, cpu_id);
+ dev->cpu = cpu_id;
+
+ dev->state_count = drv->state_count;
+
+ if (cpuidle_register_device(dev)) {
+ printk(KERN_ERR "%s: Cpuidle register device failed\n",
+ __func__);
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+late_initcall(bl_idle_init);