1 files changed, 245 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
new file mode 100644
index 00000000000..cfdbb86bc84
--- /dev/null
+++ b/arch/arm/mach-omap2/cpuidle44xx.c
@@ -0,0 +1,245 @@
+/*
+ * OMAP4 CPU idle Routines
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Santosh Shilimkar <santosh.shilimkar@ti.com>
+ * Rajendra Nayak <rnayak@ti.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/sched.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/export.h>
+#include <linux/clockchips.h>
+
+#include <asm/proc-fns.h>
+
+#include "common.h"
+#include "pm.h"
+#include "prm.h"
+
+#ifdef CONFIG_CPU_IDLE
+
+/* Machine specific information to be recorded in the C-state driver_data */
+struct omap4_idle_statedata {
+	u32 cpu_state;
+	u32 mpu_logic_state;
+	u32 mpu_state;
+	u8 valid;
+};
+
+static struct cpuidle_params cpuidle_params_table[] = {
+	/* C1 - CPU0 ON + CPU1 ON + MPU ON */
+	{.exit_latency = 2 + 2 , .target_residency = 5, .valid = 1},
+	/* C2- CPU0 OFF + CPU1 OFF + MPU CSWR */
+	{.exit_latency = 328 + 440 , .target_residency = 960, .valid = 1},
+	/* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */
+	{.exit_latency = 460 + 518 , .target_residency = 1100, .valid = 1},
+};
+
+#define OMAP4_NUM_STATES ARRAY_SIZE(cpuidle_params_table)
+
+struct omap4_idle_statedata omap4_idle_data[OMAP4_NUM_STATES];
+static struct powerdomain *mpu_pd, *cpu0_pd, *cpu1_pd;
+
+/**
+ * omap4_enter_idle - Programs OMAP4 to enter the specified state
+ * @dev: cpuidle device
+ * @drv: cpuidle driver
+ * @index: the index of state to be entered
+ *
+ * Called from the CPUidle framework to program the device to the
+ * specified low power state selected by the governor.
+ * Returns the amount of time spent in the low power state.
+ */
+static int omap4_enter_idle(struct cpuidle_device *dev,
+			struct cpuidle_driver *drv,
+			int index)
+{
+	struct omap4_idle_statedata *cx =
+			cpuidle_get_statedata(&dev->states_usage[index]);
+	struct timespec ts_preidle, ts_postidle, ts_idle;
+	u32 cpu1_state;
+	int idle_time;
+	int new_state_idx;
+	int cpu_id = smp_processor_id();
+
+	/* Used to keep track of the total time in idle */
+	getnstimeofday(&ts_preidle);
+
+	local_irq_disable();
+	local_fiq_disable();
+
+	/*
+	 * CPU0 has to stay ON (i.e in C1) until CPU1 is OFF state.
+	 * This is necessary to honour hardware recommondation
+	 * of triggeing all the possible low power modes once CPU1 is
+	 * out of coherency and in OFF mode.
+	 * Update dev->last_state so that governor stats reflects right
+	 * data.
+	 */
+	cpu1_state = pwrdm_read_pwrst(cpu1_pd);
+	if (cpu1_state != PWRDM_POWER_OFF) {
+		new_state_idx = drv->safe_state_index;
+		cx = cpuidle_get_statedata(&dev->states_usage[new_state_idx]);
+	}
+
+	if (index > 0)
+		clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu_id);
+
+	/*
+	 * Call idle CPU PM enter notifier chain so that
+	 * VFP and per CPU interrupt context is saved.
+	 */
+	if (cx->cpu_state == PWRDM_POWER_OFF)
+		cpu_pm_enter();
+
+	pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state);
+	omap_set_pwrdm_state(mpu_pd, cx->mpu_state);
+
+	/*
+	 * Call idle CPU cluster PM enter notifier chain
+	 * to save GIC and wakeupgen context.
+	 */
+	if ((cx->mpu_state == PWRDM_POWER_RET) &&
+		(cx->mpu_logic_state == PWRDM_POWER_OFF))
+			cpu_cluster_pm_enter();
+
+	omap4_enter_lowpower(dev->cpu, cx->cpu_state);
+
+	/*
+	 * Call idle CPU PM exit notifier chain to restore
+	 * VFP and per CPU IRQ context. Only CPU0 state is
+	 * considered since CPU1 is managed by CPU hotplug.
+	 */
+	if (pwrdm_read_prev_pwrst(cpu0_pd) == PWRDM_POWER_OFF)
+		cpu_pm_exit();
+
+	/*
+	 * Call idle CPU cluster PM exit notifier chain
+	 * to restore GIC and wakeupgen context.
+	 */
+	if (omap4_mpuss_read_prev_context_state())
+		cpu_cluster_pm_exit();
+
+	if (index > 0)
+		clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu_id);
+
+	getnstimeofday(&ts_postidle);
+	ts_idle = timespec_sub(ts_postidle, ts_preidle);
+
+	local_irq_enable();
+	local_fiq_enable();
+
+	idle_time = ts_idle.tv_nsec / NSEC_PER_USEC + ts_idle.tv_sec * \
+								USEC_PER_SEC;
+
+	/* Update cpuidle counters */
+	dev->last_residency = idle_time;
+
+	return index;
+}
+
+DEFINE_PER_CPU(struct cpuidle_device, omap4_idle_dev);
+
+struct cpuidle_driver omap4_idle_driver = {
+	.name =		"omap4_idle",
+	.owner =	THIS_MODULE,
+};
+
+static inline void _fill_cstate(struct cpuidle_driver *drv,
+					int idx, const char *descr)
+{
+	struct cpuidle_state *state = &drv->states[idx];
+
+	state->exit_latency	= cpuidle_params_table[idx].exit_latency;
+	state->target_residency	= cpuidle_params_table[idx].target_residency;
+	state->flags		= CPUIDLE_FLAG_TIME_VALID;
+	state->enter		= omap4_enter_idle;
+	sprintf(state->name, "C%d", idx + 1);
+	strncpy(state->desc, descr, CPUIDLE_DESC_LEN);
+}
+
+static inline struct omap4_idle_statedata *_fill_cstate_usage(
+					struct cpuidle_device *dev,
+					int idx)
+{
+	struct omap4_idle_statedata *cx = &omap4_idle_data[idx];
+	struct cpuidle_state_usage *state_usage = &dev->states_usage[idx];
+
+	cx->valid		= cpuidle_params_table[idx].valid;
+	cpuidle_set_statedata(state_usage, cx);
+
+	return cx;
+}
+
+
+
+/**
+ * omap4_idle_init - Init routine for OMAP4 idle
+ *
+ * Registers the OMAP4 specific cpuidle driver to the cpuidle
+ * framework with the valid set of states.
+ */
+int __init omap4_idle_init(void)
+{
+	struct omap4_idle_statedata *cx;
+	struct cpuidle_device *dev;
+	struct cpuidle_driver *drv = &omap4_idle_driver;
+	unsigned int cpu_id = 0;
+
+	mpu_pd = pwrdm_lookup("mpu_pwrdm");
+	cpu0_pd = pwrdm_lookup("cpu0_pwrdm");
+	cpu1_pd = pwrdm_lookup("cpu1_pwrdm");
+	if ((!mpu_pd) || (!cpu0_pd) || (!cpu1_pd))
+		return -ENODEV;
+
+
+	drv->safe_state_index = -1;
+	dev = &per_cpu(omap4_idle_dev, cpu_id);
+	dev->cpu = cpu_id;
+
+	/* C1 - CPU0 ON + CPU1 ON + MPU ON */
+	_fill_cstate(drv, 0, "MPUSS ON");
+	drv->safe_state_index = 0;
+	cx = _fill_cstate_usage(dev, 0);
+	cx->valid = 1;	/* C1 is always valid */
+	cx->cpu_state = PWRDM_POWER_ON;
+	cx->mpu_state = PWRDM_POWER_ON;
+	cx->mpu_logic_state = PWRDM_POWER_RET;
+
+	/* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */
+	_fill_cstate(drv, 1, "MPUSS CSWR");
+	cx = _fill_cstate_usage(dev, 1);
+	cx->cpu_state = PWRDM_POWER_OFF;
+	cx->mpu_state = PWRDM_POWER_RET;
+	cx->mpu_logic_state = PWRDM_POWER_RET;
+
+	/* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */
+	_fill_cstate(drv, 2, "MPUSS OSWR");
+	cx = _fill_cstate_usage(dev, 2);
+	cx->cpu_state = PWRDM_POWER_OFF;
+	cx->mpu_state = PWRDM_POWER_RET;
+	cx->mpu_logic_state = PWRDM_POWER_OFF;
+
+	drv->state_count = OMAP4_NUM_STATES;
+	cpuidle_register_driver(&omap4_idle_driver);
+
+	dev->state_count = OMAP4_NUM_STATES;
+	if (cpuidle_register_device(dev)) {
+		pr_err("%s: CPUidle register device failed\n", __func__);
+			return -EIO;
+		}
+
+	return 0;
+}
+#else
+int __init omap4_idle_init(void)
+{
+	return 0;
+}
+#endif /* CONFIG_CPU_IDLE */