From: Santosh Shilimkar <redacted>

Add OMAP5/DRA74/72 CPUIDLE support.

This patch adds MPUSS low power states in cpuidle.

        C1 - CPU0 WFI + CPU1 WFI + MPU ON
        C2 - CPU0 RET + CPU1 RET + MPU CSWR

Tested on DRA74/72-EVM for C1 and C2 states.

NOTE: DRA7 does not do voltage scaling as part of retention transition
and has Mercury which speeds up transition paths - Latency numbers are
based on measurements done by toggling GPIOs.

Signed-off-by: Santosh Shilimkar <redacted>
[ j-keerthy at ti.com rework on 3.14]
Signed-off-by: Keerthy <j-keerthy@ti.com>
[nm at ti.com: updates based on profiling, OMAP5 squashed]
Signed-off-by: Nishanth Menon <nm@ti.com>
---
 arch/arm/mach-omap2/cpuidle44xx.c |   82 ++++++++++++++++++++++++++++++++++++-
 arch/arm/mach-omap2/pm44xx.c      |    2 +-
 2 files changed, 82 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
index 2498ab0..8ad4f44 100644
--- a/arch/arm/mach-omap2/cpuidle44xx.c
+++ b/arch/arm/mach-omap2/cpuidle44xx.c

@@ -22,6 +22,7 @@
 #include "common.h"
 #include "pm.h"
 #include "prm.h"
+#include "soc.h"
 #include "clockdomain.h"
 
 #define MAX_CPUS	2

@@ -31,6 +32,7 @@ struct idle_statedata {
 	u32 cpu_state;
 	u32 mpu_logic_state;
 	u32 mpu_state;
+	u32 mpu_state_vote;
 };
 
 static struct idle_statedata omap4_idle_data[] = {

@@ -51,12 +53,26 @@ static struct idle_statedata omap4_idle_data[] = {
 	},
 };
 
+static struct idle_statedata dra7_idle_data[] = {
+	{
+		.cpu_state = PWRDM_POWER_ON,
+		.mpu_state = PWRDM_POWER_ON,
+		.mpu_logic_state = PWRDM_POWER_ON,
+	},
+	{
+		.cpu_state = PWRDM_POWER_RET,
+		.mpu_state = PWRDM_POWER_RET,
+		.mpu_logic_state = PWRDM_POWER_RET,
+	},
+};
+
 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];
+static DEFINE_RAW_SPINLOCK(mpu_lock);
 
 /* Private functions */
 

@@ -78,6 +94,32 @@ static int omap_enter_idle_simple(struct cpuidle_device *dev,
 	return index;
 }
 
+static int omap_enter_idle_smp(struct cpuidle_device *dev,
+			       struct cpuidle_driver *drv,
+			       int index)
+{
+	struct idle_statedata *cx = state_ptr + index;
+	unsigned long flag;
+
+	raw_spin_lock_irqsave(&mpu_lock, flag);
+	cx->mpu_state_vote++;
+	if (cx->mpu_state_vote == num_online_cpus()) {
+		pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state);
+		omap_set_pwrdm_state(mpu_pd, cx->mpu_state);
+	}
+	raw_spin_unlock_irqrestore(&mpu_lock, flag);
+
+	omap4_enter_lowpower(dev->cpu, cx->cpu_state);
+
+	raw_spin_lock_irqsave(&mpu_lock, flag);
+	if (cx->mpu_state_vote == num_online_cpus())
+		omap_set_pwrdm_state(mpu_pd, PWRDM_POWER_ON);
+	cx->mpu_state_vote--;
+	raw_spin_unlock_irqrestore(&mpu_lock, flag);
+
+	return index;
+}