Initial import

1 files changed, 248 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
new file mode 100644
index 000000000..4b8e9f4d5
--- /dev/null
+++ b/arch/arm/mach-omap2/cpuidle44xx.c
@@ -0,0 +1,248 @@
+/*
+ * OMAP4+ CPU idle Routines
+ *
+ * Copyright (C) 2011-2013 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/tick.h>
+
+#include <asm/cpuidle.h>
+
+#include "common.h"
+#include "pm.h"
+#include "prm.h"
+#include "clockdomain.h"
+
+#define MAX_CPUS	2
+
+/* Machine specific information */
+struct idle_statedata {
+	u32 cpu_state;
+	u32 mpu_logic_state;
+	u32 mpu_state;
+};
+
+static struct idle_statedata omap4_idle_data[] = {
+	{
+		.cpu_state = PWRDM_POWER_ON,
+		.mpu_state = PWRDM_POWER_ON,
+		.mpu_logic_state = PWRDM_POWER_RET,
+	},
+	{
+		.cpu_state = PWRDM_POWER_OFF,
+		.mpu_state = PWRDM_POWER_RET,
+		.mpu_logic_state = PWRDM_POWER_RET,
+	},
+	{
+		.cpu_state = PWRDM_POWER_OFF,
+		.mpu_state = PWRDM_POWER_RET,
+		.mpu_logic_state = PWRDM_POWER_OFF,
+	},
+};
+
+static struct powerdomain *mpu_pd, *cpu_pd[MAX_CPUS];
+static struct clockdomain *cpu_clkdm[MAX_CPUS];
+
+static atomic_t abort_barrier;
+static bool cpu_done[MAX_CPUS];
+static struct idle_statedata *state_ptr = &omap4_idle_data[0];
+
+/* Private functions */
+
+/**
+ * omap_enter_idle_[simple/coupled] - OMAP4PLUS cpuidle entry functions
+ * @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 omap_enter_idle_simple(struct cpuidle_device *dev,
+			struct cpuidle_driver *drv,
+			int index)
+{
+	omap_do_wfi();
+	return index;
+}
+
+static int omap_enter_idle_coupled(struct cpuidle_device *dev,
+			struct cpuidle_driver *drv,
+			int index)
+{
+	struct idle_statedata *cx = state_ptr + index;
+	u32 mpuss_can_lose_context = 0;
+
+	/*
+	 * CPU0 has to wait and stay ON 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.
+	 */
+	if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
+		while (pwrdm_read_pwrst(cpu_pd[1]) != PWRDM_POWER_OFF) {
+			cpu_relax();
+
+			/*
+			 * CPU1 could have already entered & exited idle
+			 * without hitting off because of a wakeup
+			 * or a failed attempt to hit off mode.  Check for
+			 * that here, otherwise we could spin forever
+			 * waiting for CPU1 off.
+			 */
+			if (cpu_done[1])
+			    goto fail;
+
+		}
+	}
+
+	mpuss_can_lose_context = (cx->mpu_state == PWRDM_POWER_RET) &&
+				 (cx->mpu_logic_state == PWRDM_POWER_OFF);
+
+	tick_broadcast_enter();
+
+	/*
+	 * Call idle CPU PM enter notifier chain so that
+	 * VFP and per CPU interrupt context is saved.
+	 */
+	cpu_pm_enter();
+
+	if (dev->cpu == 0) {
+		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 (mpuss_can_lose_context)
+			cpu_cluster_pm_enter();
+	}
+
+	omap4_enter_lowpower(dev->cpu, cx->cpu_state);
+	cpu_done[dev->cpu] = true;
+
+	/* Wakeup CPU1 only if it is not offlined */
+	if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
+
+		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) &&
+		    mpuss_can_lose_context)
+			gic_dist_disable();
+
+		clkdm_wakeup(cpu_clkdm[1]);
+		omap_set_pwrdm_state(cpu_pd[1], PWRDM_POWER_ON);
+		clkdm_allow_idle(cpu_clkdm[1]);
+
+		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) &&
+		    mpuss_can_lose_context) {
+			while (gic_dist_disabled()) {
+				udelay(1);
+				cpu_relax();
+			}
+			gic_timer_retrigger();
+		}
+	}
+
+	/*
+	 * Call idle CPU PM exit notifier chain to restore
+	 * VFP and per CPU IRQ context.
+	 */
+	cpu_pm_exit();
+
+	/*
+	 * Call idle CPU cluster PM exit notifier chain
+	 * to restore GIC and wakeupgen context.
+	 */
+	if (dev->cpu == 0 && mpuss_can_lose_context)
+		cpu_cluster_pm_exit();
+
+	tick_broadcast_exit();
+
+fail:
+	cpuidle_coupled_parallel_barrier(dev, &abort_barrier);
+	cpu_done[dev->cpu] = false;
+
+	return index;
+}
+
+/*
+ * For each cpu, setup the broadcast timer because local timers
+ * stops for the states above C1.
+ */
+static void omap_setup_broadcast_timer(void *arg)
+{
+	tick_broadcast_enable();
+}
+
+static struct cpuidle_driver omap4_idle_driver = {
+	.name				= "omap4_idle",
+	.owner				= THIS_MODULE,
+	.states = {
+		{
+			/* C1 - CPU0 ON + CPU1 ON + MPU ON */
+			.exit_latency = 2 + 2,
+			.target_residency = 5,
+			.enter = omap_enter_idle_simple,
+			.name = "C1",
+			.desc = "CPUx ON, MPUSS ON"
+		},
+		{
+			/* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */
+			.exit_latency = 328 + 440,
+			.target_residency = 960,
+			.flags = CPUIDLE_FLAG_COUPLED,
+			.enter = omap_enter_idle_coupled,
+			.name = "C2",
+			.desc = "CPUx OFF, MPUSS CSWR",
+		},
+		{
+			/* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */
+			.exit_latency = 460 + 518,
+			.target_residency = 1100,
+			.flags = CPUIDLE_FLAG_COUPLED,
+			.enter = omap_enter_idle_coupled,
+			.name = "C3",
+			.desc = "CPUx OFF, MPUSS OSWR",
+		},
+	},
+	.state_count = ARRAY_SIZE(omap4_idle_data),
+	.safe_state_index = 0,
+};
+
+/* Public functions */
+
+/**
+ * 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)
+{
+	mpu_pd = pwrdm_lookup("mpu_pwrdm");
+	cpu_pd[0] = pwrdm_lookup("cpu0_pwrdm");
+	cpu_pd[1] = pwrdm_lookup("cpu1_pwrdm");
+	if ((!mpu_pd) || (!cpu_pd[0]) || (!cpu_pd[1]))
+		return -ENODEV;
+
+	cpu_clkdm[0] = clkdm_lookup("mpu0_clkdm");
+	cpu_clkdm[1] = clkdm_lookup("mpu1_clkdm");
+	if (!cpu_clkdm[0] || !cpu_clkdm[1])
+		return -ENODEV;
+
+	/* Configure the broadcast timer on each cpu */
+	on_each_cpu(omap_setup_broadcast_timer, NULL, 1);
+
+	return cpuidle_register(&omap4_idle_driver, cpu_online_mask);
+}