Merge tag 'tegra-for-3.9-soc-cpuidle' of git://git.kernel.org/pub/scm…

…/linux/kernel/git/swarren/linux-tegra into next/soc

From Stephen Warren:
ARM: tegra: cpuidle enhancements

This pull request implements a new "LP2" cpuidle state for Tegra20,
which makes use of the couple cpuidle feature.

It is based on (most of) the previous pull request, with tag
tegra-for-3.9-soc-usb.

* tag 'tegra-for-3.9-soc-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra:
  ARM: tegra20: cpuidle: apply coupled cpuidle for powered-down mode
  ARM: tegra20: flowctrl: add support for cpu_suspend_enter/exit
  clk: tegra20: Implementing CPU low-power function for tegra_cpu_car_ops
  ARM: tegra20: cpuidle: add powered-down state for secondary CPU
  ARM: tegra: add pending SGI checking API

Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/mach-tegra/Kconfig

@@ -4,6 +4,7 @@ comment "NVIDIA Tegra options"
 
 config ARCH_TEGRA_2x_SOC
 	bool "Enable support for Tegra20 family"
+	select ARCH_NEEDS_CPU_IDLE_COUPLED if SMP
 	select ARCH_REQUIRE_GPIOLIB
 	select ARM_ERRATA_720789
 	select ARM_ERRATA_742230 if SMP

arch/arm/mach-tegra/cpuidle-tegra20.c

@@ -22,28 +22,214 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/clockchips.h>
+#include <linux/clk/tegra.h>
 
 #include <asm/cpuidle.h>
+#include <asm/proc-fns.h>
+#include <asm/suspend.h>
+#include <asm/smp_plat.h>
+
+#include "pm.h"
+#include "sleep.h"
+#include "iomap.h"
+#include "irq.h"
+#include "flowctrl.h"
+
+#ifdef CONFIG_PM_SLEEP
+static bool abort_flag;
+static atomic_t abort_barrier;
+static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev,
+				    struct cpuidle_driver *drv,
+				    int index);
+#endif
+
+static struct cpuidle_state tegra_idle_states[] = {
+	[0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
+#ifdef CONFIG_PM_SLEEP
+	[1] = {
+		.enter			= tegra20_idle_lp2_coupled,
+		.exit_latency		= 5000,
+		.target_residency	= 10000,
+		.power_usage		= 0,
+		.flags			= CPUIDLE_FLAG_TIME_VALID |
+					  CPUIDLE_FLAG_COUPLED,
+		.name			= "powered-down",
+		.desc			= "CPU power gated",
+	},
+#endif
+};
 
 static struct cpuidle_driver tegra_idle_driver = {
 	.name = "tegra_idle",
 	.owner = THIS_MODULE,
 	.en_core_tk_irqen = 1,
-	.state_count = 1,
-	.states = {
-		[0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
-	},
 };
 
 static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device);
 
+#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_SMP
+static void __iomem *pmc = IO_ADDRESS(TEGRA_PMC_BASE);
+
+static int tegra20_reset_sleeping_cpu_1(void)
+{
+	int ret = 0;
+
+	tegra_pen_lock();
+
+	if (readl(pmc + PMC_SCRATCH41) == CPU_RESETTABLE)
+		tegra20_cpu_shutdown(1);
+	else
+		ret = -EINVAL;
+
+	tegra_pen_unlock();
+
+	return ret;
+}
+
+static void tegra20_wake_cpu1_from_reset(void)
+{
+	tegra_pen_lock();
+
+	tegra20_cpu_clear_resettable();
+
+	/* enable cpu clock on cpu */
+	tegra_enable_cpu_clock(1);
+
+	/* take the CPU out of reset */
+	tegra_cpu_out_of_reset(1);
+
+	/* unhalt the cpu */
+	flowctrl_write_cpu_halt(1, 0);
+
+	tegra_pen_unlock();
+}
+
+static int tegra20_reset_cpu_1(void)
+{
+	if (!cpu_online(1) || !tegra20_reset_sleeping_cpu_1())
+		return 0;
+
+	tegra20_wake_cpu1_from_reset();
+	return -EBUSY;
+}
+#else
+static inline void tegra20_wake_cpu1_from_reset(void)
+{
+}
+
+static inline int tegra20_reset_cpu_1(void)
+{
+	return 0;
+}
+#endif
+
+static bool tegra20_cpu_cluster_power_down(struct cpuidle_device *dev,
+					   struct cpuidle_driver *drv,
+					   int index)
+{
+	struct cpuidle_state *state = &drv->states[index];
+	u32 cpu_on_time = state->exit_latency;
+	u32 cpu_off_time = state->target_residency - state->exit_latency;
+
+	while (tegra20_cpu_is_resettable_soon())
+		cpu_relax();
+
+	if (tegra20_reset_cpu_1() || !tegra_cpu_rail_off_ready())
+		return false;
+
+	clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu);
+
+	tegra_idle_lp2_last(cpu_on_time, cpu_off_time);
+
+	clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
+
+	if (cpu_online(1))
+		tegra20_wake_cpu1_from_reset();
+
+	return true;
+}
+
+#ifdef CONFIG_SMP
+static bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev,
+					 struct cpuidle_driver *drv,
+					 int index)
+{
+	clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu);
+
+	cpu_suspend(0, tegra20_sleep_cpu_secondary_finish);
+
+	tegra20_cpu_clear_resettable();
+
+	clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
+
+	return true;
+}
+#else
+static inline bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev,
+						struct cpuidle_driver *drv,
+						int index)
+{
+	return true;
+}
+#endif
+
+static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev,
+				    struct cpuidle_driver *drv,
+				    int index)
+{
+	u32 cpu = is_smp() ? cpu_logical_map(dev->cpu) : dev->cpu;
+	bool entered_lp2 = false;
+
+	if (tegra_pending_sgi())
+		ACCESS_ONCE(abort_flag) = true;
+
+	cpuidle_coupled_parallel_barrier(dev, &abort_barrier);
+
+	if (abort_flag) {
+		cpuidle_coupled_parallel_barrier(dev, &abort_barrier);
+		abort_flag = false;	/* clean flag for next coming */
+		return -EINTR;
+	}
+
+	local_fiq_disable();
+
+	tegra_set_cpu_in_lp2(cpu);
+	cpu_pm_enter();
+
+	if (cpu == 0)
+		entered_lp2 = tegra20_cpu_cluster_power_down(dev, drv, index);
+	else
+		entered_lp2 = tegra20_idle_enter_lp2_cpu_1(dev, drv, index);
+
+	cpu_pm_exit();
+	tegra_clear_cpu_in_lp2(cpu);
+
+	local_fiq_enable();
+
+	smp_rmb();
+
+	return entered_lp2 ? index : 0;
+}
+#endif
+
 int __init tegra20_cpuidle_init(void)
 {
 	int ret;
 	unsigned int cpu;
 	struct cpuidle_device *dev;
 	struct cpuidle_driver *drv = &tegra_idle_driver;
 
+#ifdef CONFIG_PM_SLEEP
+	tegra_tear_down_cpu = tegra20_tear_down_cpu;
+#endif
+
+	drv->state_count = ARRAY_SIZE(tegra_idle_states);
+	memcpy(drv->states, tegra_idle_states,
+			drv->state_count * sizeof(drv->states[0]));
+
 	ret = cpuidle_register_driver(&tegra_idle_driver);
 	if (ret) {
 		pr_err("CPUidle driver registration failed\n");
@@ -53,6 +239,9 @@ int __init tegra20_cpuidle_init(void)
 	for_each_possible_cpu(cpu) {
 		dev = &per_cpu(tegra_idle_device, cpu);
 		dev->cpu = cpu;
+#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
+		dev->coupled_cpus = *cpu_possible_mask;
+#endif
 
 		dev->state_count = drv->state_count;
 		ret = cpuidle_register_device(dev);

arch/arm/mach-tegra/flowctrl.c

@@ -25,6 +25,7 @@
 
 #include "flowctrl.h"
 #include "iomap.h"
+#include "fuse.h"
 
 static u8 flowctrl_offset_halt_cpu[] = {
 	FLOW_CTRL_HALT_CPU0_EVENTS,
@@ -75,11 +76,26 @@ void flowctrl_cpu_suspend_enter(unsigned int cpuid)
 	int i;
 
 	reg = flowctrl_read_cpu_csr(cpuid);
-	reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP;	/* clear wfe bitmap */
-	reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP;	/* clear wfi bitmap */
+	switch (tegra_chip_id) {
+	case TEGRA20:
+		/* clear wfe bitmap */
+		reg &= ~TEGRA20_FLOW_CTRL_CSR_WFE_BITMAP;
+		/* clear wfi bitmap */
+		reg &= ~TEGRA20_FLOW_CTRL_CSR_WFI_BITMAP;
+		/* pwr gating on wfe */
+		reg |= TEGRA20_FLOW_CTRL_CSR_WFE_CPU0 << cpuid;
+		break;
+	case TEGRA30:
+		/* clear wfe bitmap */
+		reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP;
+		/* clear wfi bitmap */
+		reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP;
+		/* pwr gating on wfi */
+		reg |= TEGRA30_FLOW_CTRL_CSR_WFI_CPU0 << cpuid;
+		break;
+	}
 	reg |= FLOW_CTRL_CSR_INTR_FLAG;			/* clear intr flag */
 	reg |= FLOW_CTRL_CSR_EVENT_FLAG;		/* clear event flag */
-	reg |= TEGRA30_FLOW_CTRL_CSR_WFI_CPU0 << cpuid;	/* pwr gating on wfi */
 	reg |= FLOW_CTRL_CSR_ENABLE;			/* pwr gating */
 	flowctrl_write_cpu_csr(cpuid, reg);
 
@@ -99,8 +115,20 @@ void flowctrl_cpu_suspend_exit(unsigned int cpuid)
 
 	/* Disable powergating via flow controller for CPU0 */
 	reg = flowctrl_read_cpu_csr(cpuid);
-	reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP;	/* clear wfe bitmap */
-	reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP;	/* clear wfi bitmap */
+	switch (tegra_chip_id) {
+	case TEGRA20:
+		/* clear wfe bitmap */
+		reg &= ~TEGRA20_FLOW_CTRL_CSR_WFE_BITMAP;
+		/* clear wfi bitmap */
+		reg &= ~TEGRA20_FLOW_CTRL_CSR_WFI_BITMAP;
+		break;
+	case TEGRA30:
+		/* clear wfe bitmap */
+		reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP;
+		/* clear wfi bitmap */
+		reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP;
+		break;
+	}
 	reg &= ~FLOW_CTRL_CSR_ENABLE;			/* clear enable */
 	reg |= FLOW_CTRL_CSR_INTR_FLAG;			/* clear intr */
 	reg |= FLOW_CTRL_CSR_EVENT_FLAG;		/* clear event */

arch/arm/mach-tegra/flowctrl.h

@@ -34,6 +34,10 @@
 #define FLOW_CTRL_HALT_CPU1_EVENTS	0x14
 #define FLOW_CTRL_CPU1_CSR		0x18
 
+#define TEGRA20_FLOW_CTRL_CSR_WFE_CPU0		(1 << 4)
+#define TEGRA20_FLOW_CTRL_CSR_WFE_BITMAP	(3 << 4)
+#define TEGRA20_FLOW_CTRL_CSR_WFI_BITMAP	0
+
 #define TEGRA30_FLOW_CTRL_CSR_WFI_CPU0		(1 << 8)
 #define TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP	(0xF << 4)
 #define TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP	(0xF << 8)

arch/arm/mach-tegra/irq.c

@@ -44,6 +44,8 @@
 
 #define FIRST_LEGACY_IRQ 32
 
+#define SGI_MASK 0xFFFF
+
 static int num_ictlrs;
 
 static void __iomem *ictlr_reg_base[] = {
@@ -54,6 +56,19 @@ static void __iomem *ictlr_reg_base[] = {
 	IO_ADDRESS(TEGRA_QUINARY_ICTLR_BASE),
 };
 
+bool tegra_pending_sgi(void)
+{
+	u32 pending_set;
+	void __iomem *distbase = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
+
+	pending_set = readl_relaxed(distbase + GIC_DIST_PENDING_SET);
+
+	if (pending_set & SGI_MASK)
+		return true;
+
+	return false;
+}
+
 static inline void tegra_irq_write_mask(unsigned int irq, unsigned long reg)
 {
 	void __iomem *base;

arch/arm/mach-tegra/irq.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2012, NVIDIA Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __TEGRA_IRQ_H
+#define __TEGRA_IRQ_H
+
+bool tegra_pending_sgi(void);
+
+#endif

arch/arm/mach-tegra/pm.c

@@ -36,6 +36,7 @@
 #include "iomap.h"
 #include "reset.h"
 #include "flowctrl.h"
+#include "fuse.h"
 #include "sleep.h"
 
 #define TEGRA_POWER_CPU_PWRREQ_OE	(1 << 16)  /* CPU pwr req enable */
@@ -173,6 +174,8 @@ bool tegra_set_cpu_in_lp2(int phy_cpu_id)
 
 	if ((phy_cpu_id == 0) && cpumask_equal(cpu_lp2_mask, cpu_online_mask))
 		last_cpu = true;
+	else if (tegra_chip_id == TEGRA20 && phy_cpu_id == 1)
+		tegra20_cpu_set_resettable_soon();
 
 	spin_unlock(&tegra_lp2_lock);
 	return last_cpu;