Initial import

1 files changed, 337 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/cpuidle34xx.c b/arch/arm/mach-omap2/cpuidle34xx.c
new file mode 100644
index 000000000..aa7b379e2
--- /dev/null
+++ b/arch/arm/mach-omap2/cpuidle34xx.c
@@ -0,0 +1,337 @@
+/*
+ * linux/arch/arm/mach-omap2/cpuidle34xx.c
+ *
+ * OMAP3 CPU IDLE Routines
+ *
+ * Copyright (C) 2008 Texas Instruments, Inc.
+ * Rajendra Nayak <rnayak@ti.com>
+ *
+ * Copyright (C) 2007 Texas Instruments, Inc.
+ * Karthik Dasu <karthik-dp@ti.com>
+ *
+ * Copyright (C) 2006 Nokia Corporation
+ * Tony Lindgren <tony@atomide.com>
+ *
+ * Copyright (C) 2005 Texas Instruments, Inc.
+ * Richard Woodruff <r-woodruff2@ti.com>
+ *
+ * Based on pm.c for omap2
+ *
+ * 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/export.h>
+#include <linux/cpu_pm.h>
+#include <asm/cpuidle.h>
+
+#include "powerdomain.h"
+#include "clockdomain.h"
+
+#include "pm.h"
+#include "control.h"
+#include "common.h"
+
+/* Mach specific information to be recorded in the C-state driver_data */
+struct omap3_idle_statedata {
+	u8 mpu_state;
+	u8 core_state;
+	u8 per_min_state;
+	u8 flags;
+};
+
+static struct powerdomain *mpu_pd, *core_pd, *per_pd, *cam_pd;
+
+/*
+ * Possible flag bits for struct omap3_idle_statedata.flags:
+ *
+ * OMAP_CPUIDLE_CX_NO_CLKDM_IDLE: don't allow the MPU clockdomain to go
+ *    inactive.  This in turn prevents the MPU DPLL from entering autoidle
+ *    mode, so wakeup latency is greatly reduced, at the cost of additional
+ *    energy consumption.  This also prevents the CORE clockdomain from
+ *    entering idle.
+ */
+#define OMAP_CPUIDLE_CX_NO_CLKDM_IDLE		BIT(0)
+
+/*
+ * Prevent PER OFF if CORE is not in RETention or OFF as this would
+ * disable PER wakeups completely.
+ */
+static struct omap3_idle_statedata omap3_idle_data[] = {
+	{
+		.mpu_state = PWRDM_POWER_ON,
+		.core_state = PWRDM_POWER_ON,
+		/* In C1 do not allow PER state lower than CORE state */
+		.per_min_state = PWRDM_POWER_ON,
+		.flags = OMAP_CPUIDLE_CX_NO_CLKDM_IDLE,
+	},
+	{
+		.mpu_state = PWRDM_POWER_ON,
+		.core_state = PWRDM_POWER_ON,
+		.per_min_state = PWRDM_POWER_RET,
+	},
+	{
+		.mpu_state = PWRDM_POWER_RET,
+		.core_state = PWRDM_POWER_ON,
+		.per_min_state = PWRDM_POWER_RET,
+	},
+	{
+		.mpu_state = PWRDM_POWER_OFF,
+		.core_state = PWRDM_POWER_ON,
+		.per_min_state = PWRDM_POWER_RET,
+	},
+	{
+		.mpu_state = PWRDM_POWER_RET,
+		.core_state = PWRDM_POWER_RET,
+		.per_min_state = PWRDM_POWER_OFF,
+	},
+	{
+		.mpu_state = PWRDM_POWER_OFF,
+		.core_state = PWRDM_POWER_RET,
+		.per_min_state = PWRDM_POWER_OFF,
+	},
+	{
+		.mpu_state = PWRDM_POWER_OFF,
+		.core_state = PWRDM_POWER_OFF,
+		.per_min_state = PWRDM_POWER_OFF,
+	},
+};
+
+/**
+ * omap3_enter_idle - Programs OMAP3 to enter the specified state
+ * @dev: cpuidle device
+ * @drv: cpuidle driver
+ * @index: the index of state to be entered
+ */
+static int omap3_enter_idle(struct cpuidle_device *dev,
+			    struct cpuidle_driver *drv,
+			    int index)
+{
+	struct omap3_idle_statedata *cx = &omap3_idle_data[index];
+
+	if (omap_irq_pending() || need_resched())
+		goto return_sleep_time;
+
+	/* Deny idle for C1 */
+	if (cx->flags & OMAP_CPUIDLE_CX_NO_CLKDM_IDLE) {
+		clkdm_deny_idle(mpu_pd->pwrdm_clkdms[0]);
+	} else {
+		pwrdm_set_next_pwrst(mpu_pd, cx->mpu_state);
+		pwrdm_set_next_pwrst(core_pd, cx->core_state);
+	}
+
+	/*
+	 * Call idle CPU PM enter notifier chain so that
+	 * VFP context is saved.
+	 */
+	if (cx->mpu_state == PWRDM_POWER_OFF)
+		cpu_pm_enter();
+
+	/* Execute ARM wfi */
+	omap_sram_idle();
+
+	/*
+	 * Call idle CPU PM enter notifier chain to restore
+	 * VFP context.
+	 */
+	if (cx->mpu_state == PWRDM_POWER_OFF &&
+	    pwrdm_read_prev_pwrst(mpu_pd) == PWRDM_POWER_OFF)
+		cpu_pm_exit();
+
+	/* Re-allow idle for C1 */
+	if (cx->flags & OMAP_CPUIDLE_CX_NO_CLKDM_IDLE)
+		clkdm_allow_idle(mpu_pd->pwrdm_clkdms[0]);
+
+return_sleep_time:
+
+	return index;
+}
+
+/**
+ * next_valid_state - Find next valid C-state
+ * @dev: cpuidle device
+ * @drv: cpuidle driver
+ * @index: Index of currently selected c-state
+ *
+ * If the state corresponding to index is valid, index is returned back
+ * to the caller. Else, this function searches for a lower c-state which is
+ * still valid (as defined in omap3_power_states[]) and returns its index.
+ *
+ * A state is valid if the 'valid' field is enabled and
+ * if it satisfies the enable_off_mode condition.
+ */
+static int next_valid_state(struct cpuidle_device *dev,
+			    struct cpuidle_driver *drv, int index)
+{
+	struct omap3_idle_statedata *cx = &omap3_idle_data[index];
+	u32 mpu_deepest_state = PWRDM_POWER_RET;
+	u32 core_deepest_state = PWRDM_POWER_RET;
+	int idx;
+	int next_index = 0; /* C1 is the default value */
+
+	if (enable_off_mode) {
+		mpu_deepest_state = PWRDM_POWER_OFF;
+		/*
+		 * Erratum i583: valable for ES rev < Es1.2 on 3630.
+		 * CORE OFF mode is not supported in a stable form, restrict
+		 * instead the CORE state to RET.
+		 */
+		if (!IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583))
+			core_deepest_state = PWRDM_POWER_OFF;
+	}
+
+	/* Check if current state is valid */
+	if ((cx->mpu_state >= mpu_deepest_state) &&
+	    (cx->core_state >= core_deepest_state))
+		return index;
+
+	/*
+	 * Drop to next valid state.
+	 * Start search from the next (lower) state.
+	 */
+	for (idx = index - 1; idx >= 0; idx--) {
+		cx = &omap3_idle_data[idx];
+		if ((cx->mpu_state >= mpu_deepest_state) &&
+		    (cx->core_state >= core_deepest_state)) {
+			next_index = idx;
+			break;
+		}
+	}
+
+	return next_index;
+}
+
+/**
+ * omap3_enter_idle_bm - Checks for any bus activity
+ * @dev: cpuidle device
+ * @drv: cpuidle driver
+ * @index: array index of target state to be programmed
+ *
+ * This function checks for any pending activity and then programs
+ * the device to the specified or a safer state.
+ */
+static int omap3_enter_idle_bm(struct cpuidle_device *dev,
+			       struct cpuidle_driver *drv,
+			       int index)
+{
+	int new_state_idx, ret;
+	u8 per_next_state, per_saved_state;
+	struct omap3_idle_statedata *cx;
+
+	/*
+	 * Use only C1 if CAM is active.
+	 * CAM does not have wakeup capability in OMAP3.
+	 */
+	if (pwrdm_read_pwrst(cam_pd) == PWRDM_POWER_ON)
+		new_state_idx = drv->safe_state_index;
+	else
+		new_state_idx = next_valid_state(dev, drv, index);
+
+	/*
+	 * FIXME: we currently manage device-specific idle states
+	 *        for PER and CORE in combination with CPU-specific
+	 *        idle states.  This is wrong, and device-specific
+	 *        idle management needs to be separated out into
+	 *        its own code.
+	 */
+
+	/* Program PER state */
+	cx = &omap3_idle_data[new_state_idx];
+
+	per_next_state = pwrdm_read_next_pwrst(per_pd);
+	per_saved_state = per_next_state;
+	if (per_next_state < cx->per_min_state) {
+		per_next_state = cx->per_min_state;
+		pwrdm_set_next_pwrst(per_pd, per_next_state);
+	}
+
+	ret = omap3_enter_idle(dev, drv, new_state_idx);
+
+	/* Restore original PER state if it was modified */
+	if (per_next_state != per_saved_state)
+		pwrdm_set_next_pwrst(per_pd, per_saved_state);
+
+	return ret;
+}
+
+static struct cpuidle_driver omap3_idle_driver = {
+	.name             = "omap3_idle",
+	.owner            = THIS_MODULE,
+	.states = {
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 2 + 2,
+			.target_residency = 5,
+			.name		  = "C1",
+			.desc		  = "MPU ON + CORE ON",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 10 + 10,
+			.target_residency = 30,
+			.name		  = "C2",
+			.desc		  = "MPU ON + CORE ON",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 50 + 50,
+			.target_residency = 300,
+			.name		  = "C3",
+			.desc		  = "MPU RET + CORE ON",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 1500 + 1800,
+			.target_residency = 4000,
+			.name		  = "C4",
+			.desc		  = "MPU OFF + CORE ON",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 2500 + 7500,
+			.target_residency = 12000,
+			.name		  = "C5",
+			.desc		  = "MPU RET + CORE RET",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 3000 + 8500,
+			.target_residency = 15000,
+			.name		  = "C6",
+			.desc		  = "MPU OFF + CORE RET",
+		},
+		{
+			.enter		  = omap3_enter_idle_bm,
+			.exit_latency	  = 10000 + 30000,
+			.target_residency = 30000,
+			.name		  = "C7",
+			.desc		  = "MPU OFF + CORE OFF",
+		},
+	},
+	.state_count = ARRAY_SIZE(omap3_idle_data),
+	.safe_state_index = 0,
+};
+
+/* Public functions */
+
+/**
+ * omap3_idle_init - Init routine for OMAP3 idle
+ *
+ * Registers the OMAP3 specific cpuidle driver to the cpuidle
+ * framework with the valid set of states.
+ */
+int __init omap3_idle_init(void)
+{
+	mpu_pd = pwrdm_lookup("mpu_pwrdm");
+	core_pd = pwrdm_lookup("core_pwrdm");
+	per_pd = pwrdm_lookup("per_pwrdm");
+	cam_pd = pwrdm_lookup("cam_pwrdm");
+
+	if (!mpu_pd || !core_pd || !per_pd || !cam_pd)
+		return -ENODEV;
+
+	return cpuidle_register(&omap3_idle_driver, NULL);
+}