ARM: ux500: Add suspend support

Change-Id: I039557aed52693dfad9b76ea0f2f746193aa4316
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/32074

5 files changed, 157 insertions, 4 deletions

diff --git a/arch/arm/configs/u8500_defconfig b/arch/arm/configs/u8500_defconfig
index 3d534f7d33f..0dfc7040436 100755
--- a/arch/arm/configs/u8500_defconfig
+++ b/arch/arm/configs/u8500_defconfig
@@ -37,6 +37,7 @@ CONFIG_DISPLAY_AV8100_TRIPPLE_BUFFER=y
 CONFIG_DBX500_PRCMU_QOS_POWER=y
 CONFIG_DBX500_PRCMU_DEBUG=y
 # CONFIG_UX500_DEBUG_NO_LAUTERBACH is not set
+CONFIG_UX500_SUSPEND=y
 CONFIG_UX500_CONTEXT=y
 CONFIG_CPU_FREQ=y
 CONFIG_CPU_FREQ_STAT_DETAILS=y
diff --git a/arch/arm/mach-ux500/hotplug.c b/arch/arm/mach-ux500/hotplug.c
index 5a05b15cc87..0cf4798aa07 100644
--- a/arch/arm/mach-ux500/hotplug.c
+++ b/arch/arm/mach-ux500/hotplug.c
@@ -15,20 +15,29 @@
 
 #include <asm/cacheflush.h>
 
+#include <mach/context.h>
+
 extern volatile int pen_release;
 
+static DECLARE_COMPLETION(cpu_killed);
+
 static inline void platform_do_lowpower(unsigned int cpu)
 {
 	flush_cache_all();
 
 	for (;;) {
 
-		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
-				     : : : "memory");
+		context_varm_save_core();
+		context_save_cpu_registers();
+
+		context_save_to_sram_and_wfi(false);
+
+		context_restore_cpu_registers();
+		context_varm_restore_core();
 
 		if (pen_release == cpu) {
 			/*
-			 * OK, proper wakeup, we're done
+			* OK, proper wakeup, we're done
 			 */
 			break;
 		}
@@ -37,7 +46,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
 
 int platform_cpu_kill(unsigned int cpu)
 {
-	return 1;
+	return wait_for_completion_timeout(&cpu_killed, 5000);
 }
 
 /*
@@ -47,6 +56,19 @@ int platform_cpu_kill(unsigned int cpu)
  */
 void platform_cpu_die(unsigned int cpu)
 {
+#ifdef DEBUG
+	unsigned int this_cpu = hard_smp_processor_id();
+
+	if (cpu != this_cpu) {
+		printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n",
+			   this_cpu, cpu);
+		BUG();
+	}
+#endif
+
+	printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
+	complete(&cpu_killed);
+
 	/* directly enter low power state, skipping secure registers */
 	platform_do_lowpower(cpu);
 }
diff --git a/arch/arm/mach-ux500/pm/Kconfig b/arch/arm/mach-ux500/pm/Kconfig
index cfa12977bc0..0a449421eca 100644
--- a/arch/arm/mach-ux500/pm/Kconfig
+++ b/arch/arm/mach-ux500/pm/Kconfig
@@ -18,3 +18,10 @@ config UX500_PM_PERFORMANCE
 	help
 	  Enable supervision of events which may require a boost
 	  of platform performance.
+
+config UX500_SUSPEND
+	bool "Suspend to mem and standby support"
+	depends on (UX500_SOC_DB8500 || UX500_SOC_DB5500) && PM && SUSPEND
+	select UX500_CONTEXT
+	help
+	  Add support for suspend.
diff --git a/arch/arm/mach-ux500/pm/Makefile b/arch/arm/mach-ux500/pm/Makefile
index 9f2aa590c6b..68112b371a4 100644
--- a/arch/arm/mach-ux500/pm/Makefile
+++ b/arch/arm/mach-ux500/pm/Makefile
@@ -5,4 +5,5 @@ obj-y := pm.o runtime.o no_suspend.o
 
 obj-$(CONFIG_DBX500_PRCMU_QOS_POWER)	+= prcmu-qos-power.o
 obj-$(CONFIG_UX500_CONTEXT) 		+= context.o context_arm.o context-db8500.o context-db5500.o
+obj-$(CONFIG_UX500_SUSPEND)		+= suspend.o
 obj-$(CONFIG_UX500_PM_PERFORMANCE)	+= performance.o
diff --git a/arch/arm/mach-ux500/pm/suspend.c b/arch/arm/mach-ux500/pm/suspend.c
new file mode 100644
index 00000000000..a3ad87c6d84
--- /dev/null
+++ b/arch/arm/mach-ux500/pm/suspend.c
@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) STMicroelectronics 2009
+ * Copyright (C) ST-Ericsson SA 2010-2011
+ *
+ * License Terms: GNU General Public License v2
+ *
+ * Authors: Rickard Andersson <rickard.andersson@stericsson.com>,
+ *	    Jonas Aaberg <jonas.aberg@stericsson.com>,
+ *          Sundar Iyer for ST-Ericsson.
+ */
+
+#include <linux/suspend.h>
+#include <linux/mfd/dbx500-prcmu.h>
+
+#include <mach/context.h>
+#include <mach/pm.h>
+
+static int suspend(bool do_deepsleep)
+{
+	int ret = 0;
+
+	/* configure the prcm for a sleep wakeup */
+	prcmu_enable_wakeups(PRCMU_WAKEUP(ABB));
+
+	context_vape_save();
+
+	ux500_pm_gic_decouple();
+
+	if (ux500_pm_gic_pending_interrupt()) {
+		pr_info("suspend/resume: pending interrupt\n");
+
+		/* Recouple GIC with the interrupt bus */
+		ux500_pm_gic_recouple();
+		ret = -EBUSY;
+
+		goto exit;
+	}
+	ux500_pm_prcmu_set_ioforce(true);
+
+	if (do_deepsleep) {
+		context_varm_save_common();
+		context_varm_save_core();
+		context_gic_dist_disable_unneeded_irqs();
+		context_save_cpu_registers();
+
+		/*
+		 * Due to we have only 100us between requesting a powerstate
+		 * and wfi, we clean the cache before as well to assure the
+		 * final cache clean before wfi has as little as possible to
+		 * do.
+		 */
+		context_clean_l1_cache_all();
+
+		(void) prcmu_set_power_state(PRCMU_AP_DEEP_SLEEP,
+					     false, false);
+		context_save_to_sram_and_wfi(true);
+
+		context_restore_cpu_registers();
+		context_varm_restore_core();
+		context_varm_restore_common();
+
+	} else {
+
+		context_clean_l1_cache_all();
+		(void) prcmu_set_power_state(APEXECUTE_TO_APSLEEP,
+					     false, false);
+		dsb();
+		__asm__ __volatile__("wfi\n\t" : : : "memory");
+	}
+
+	context_vape_restore();
+
+	/* APE was turned off, restore IO ring */
+	ux500_pm_prcmu_set_ioforce(false);
+
+exit:
+	/* This is what cpuidle wants */
+	prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) |
+			     PRCMU_WAKEUP(ABB));
+	return ret;
+}
+
+static int ux500_suspend_enter(suspend_state_t state)
+{
+	if (state == PM_SUSPEND_MEM)
+		return suspend(true);
+	else if (state == PM_SUSPEND_STANDBY)
+		return suspend(false);
+	else
+		return -EINVAL;
+}
+
+static int ux500_suspend_valid(suspend_state_t state)
+{
+	return state == PM_SUSPEND_MEM || state == PM_SUSPEND_STANDBY;
+}
+
+static int ux500_suspend_prepare_late(void)
+{
+	/* ESRAM to retention instead of OFF until ROM is fixed */
+	(void) prcmu_config_esram0_deep_sleep(ESRAM0_DEEP_SLEEP_STATE_RET);
+	return 0;
+}
+
+static void ux500_suspend_wake(void)
+{
+	(void) prcmu_config_esram0_deep_sleep(ESRAM0_DEEP_SLEEP_STATE_RET);
+}
+
+static struct platform_suspend_ops ux500_suspend_ops = {
+	.enter	      = ux500_suspend_enter,
+	.valid	      = ux500_suspend_valid,
+	.prepare_late = ux500_suspend_prepare_late,
+	.wake	      = ux500_suspend_wake,
+};
+
+static __init int ux500_suspend_init(void)
+{
+	suspend_set_ops(&ux500_suspend_ops);
+	return 0;
+}
+device_initcall(ux500_suspend_init);