ARM: tegra: Catch early LP2 exits

Change-Id: I107d301ec8e8cd3b69ea293faab15b8d766e38f4
Signed-off-by: Scott Williams <scwilliams@nvidia.com>
DW: Split into logical changes
Signed-off-by: Dan Willemsen <dwillemsen@nvidia.com>

Rebase-Id: R9f8f016c1850e2c65f30f2f67241a94acf8a7755

4 files changed, 26 insertions, 3 deletions

diff --git a/arch/arm/mach-tegra/cpuidle-t2.c b/arch/arm/mach-tegra/cpuidle-t2.c
index 446dea09479e..0fccb335e1cb 100644
--- a/arch/arm/mach-tegra/cpuidle-t2.c
+++ b/arch/arm/mach-tegra/cpuidle-t2.c
@@ -151,6 +151,7 @@ bool tegra2_lp2_is_allowed(struct cpuidle_device *dev,
 static int tegra2_idle_lp2_last(struct cpuidle_device *dev,
 			struct cpuidle_state *state, s64 request)
 {
+	bool sleep_completed = false;
 	int i;
 
 	while (tegra2_cpu_is_resettable_soon())
@@ -165,7 +166,10 @@ static int tegra2_idle_lp2_last(struct cpuidle_device *dev,
 		return -EBUSY;
 	}
 
-	tegra_idle_lp2_last(request, 0);
+	if (tegra_idle_lp2_last(request, 0) == 0)
+		sleep_completed = true;
+	else
+		idle_stats.lp2_int_count[tegra_pending_interrupt()]++;
 
 	for_each_online_cpu(i) {
 		if (i != dev->cpu) {
@@ -174,6 +178,13 @@ static int tegra2_idle_lp2_last(struct cpuidle_device *dev,
 		}
 	}
 
+	if (sleep_completed) {
+		/*
+		 * Stayed in LP2 for the full time until the next tick
+		 */
+		pr_debug("%lld\n", request);
+	}
+
 	return 0;
 }
 
diff --git a/arch/arm/mach-tegra/cpuidle.h b/arch/arm/mach-tegra/cpuidle.h
index 8f17ba66aa85..35c3360a6e17 100644
--- a/arch/arm/mach-tegra/cpuidle.h
+++ b/arch/arm/mach-tegra/cpuidle.h
@@ -73,6 +73,15 @@ static inline int tegra_lp2_debug_show(struct seq_file *s, void *data)
 }
 #endif
 
+static inline int tegra_pending_interrupt(void)
+{
+	void __iomem *gic_cpu = IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x100);
+	u32 reg = readl(gic_cpu + 0x18);
+	reg &= 0x3FF;
+
+	return reg;
+}
+
 #ifdef CONFIG_CPU_IDLE
 void tegra_lp2_in_idle(bool enable);
 #else
diff --git a/arch/arm/mach-tegra/pm.c b/arch/arm/mach-tegra/pm.c
index 5775208e67d9..c13b17a993ad 100644
--- a/arch/arm/mach-tegra/pm.c
+++ b/arch/arm/mach-tegra/pm.c
@@ -425,9 +425,10 @@ bool tegra_set_cpu_in_lp2(int cpu)
 	return last_cpu;
 }
 
-void tegra_idle_lp2_last(unsigned int sleep_time, unsigned int flags)
+unsigned int tegra_idle_lp2_last(unsigned int sleep_time, unsigned int flags)
 {
 	u32 reg;
+	unsigned int remain;
 
 	/* Only the last cpu down does the final suspend steps */
 	reg = readl(pmc + PMC_CTRL);
@@ -469,6 +470,7 @@ void tegra_idle_lp2_last(unsigned int sleep_time, unsigned int flags)
 	restore_cpu_complex();
 	cpu_complex_pm_exit();
 
+	remain = tegra_lp2_timer_remain();
 	if (sleep_time)
 		tegra_lp2_set_trigger(0);
 
@@ -491,6 +493,7 @@ void tegra_idle_lp2_last(unsigned int sleep_time, unsigned int flags)
 			tegra_cluster_switch_times[tegra_cluster_switch_time_id_start]);
 	}
 #endif
+	return remain;
 }
 
 static int tegra_common_suspend(void)
diff --git a/arch/arm/mach-tegra/pm.h b/arch/arm/mach-tegra/pm.h
index 9a689a857ebb..cb9c9fc306e6 100644
--- a/arch/arm/mach-tegra/pm.h
+++ b/arch/arm/mach-tegra/pm.h
@@ -102,7 +102,7 @@ u64 tegra_rtc_read_ms(void);
  */
 extern void (*tegra_deep_sleep)(int);
 
-void tegra_idle_lp2_last(unsigned int us, unsigned int flags);
+unsigned int tegra_idle_lp2_last(unsigned int us, unsigned int flags);
 
 #ifdef CONFIG_ARCH_TEGRA_2x_SOC