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diff --git a/kernel/arch/arm/mach-omap2/cpuidle34xx.c b/kernel/arch/arm/mach-omap2/cpuidle34xx.c
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+/*
+ * 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);
+}