[PATCHv2 19/19] ARM: OMAP4: powerdomain: update mpu / core off counters during device off

[Tero Kristo]

Currently device off does not have any counters / timers of its own
and it is impossible to track the time spent in this state. In device
off, MPU / CORE powerdomains enter OSWR, so normally the RETENTION
state times / counts are increased during device off.

This patch adds a new field to the powerdomain struct for context loss
register, which is checked during pwrdm_post_transition to see if
a device off type context loss has happened. If this is the case,
the counters + timers for OFF state are touched instead of RETENTION.

Signed-off-by: Tero Kristo <t-kristo at ti.com>
---
 arch/arm/mach-omap2/omap-mpuss-lowpower.c   |    1 -
 arch/arm/mach-omap2/powerdomain.c           |    9 +++++++++
 arch/arm/mach-omap2/powerdomain.h           |    2 ++
 arch/arm/mach-omap2/powerdomains44xx_data.c |    2 ++
 arch/arm/mach-omap2/prm44xx.c               |   15 +++++++++++++++
 arch/arm/mach-omap2/prm44xx.h               |    2 ++
 6 files changed, 30 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
index 1f06f97..f187025 100644
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -404,7 +404,6 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
 	if (omap4_device_prev_state_off()) {
 		omap4_dpll_resume_off();
 		omap4_cm_resume_off();
-		omap4_device_clear_prev_off_state();
 	}
 
 sar_save_failed:
diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c
index 96ad3dbe..f13bb2c 100644
--- a/arch/arm/mach-omap2/powerdomain.c
+++ b/arch/arm/mach-omap2/powerdomain.c
@@ -156,6 +156,15 @@ static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
 		break;
 	case PWRDM_STATE_PREV:
 		prev = pwrdm_read_prev_pwrst(pwrdm);
+
+		/*
+		 * If powerdomain has context offset defined, check if
+		 * the domain has lost context (i.e. entered off)
+		 */
+		if (pwrdm->context_offs)
+			if (omap4_pwrdm_lost_context_rff(pwrdm->prcm_offs,
+							 pwrdm->context_offs))
+				prev = PWRDM_POWER_OFF;
 		if (pwrdm->state != prev)
 			pwrdm->state_counter[prev]++;
 		if (prev == PWRDM_POWER_RET)
diff --git a/arch/arm/mach-omap2/powerdomain.h b/arch/arm/mach-omap2/powerdomain.h
index 0d72a8a..a427645 100644
--- a/arch/arm/mach-omap2/powerdomain.h
+++ b/arch/arm/mach-omap2/powerdomain.h
@@ -82,6 +82,7 @@ struct powerdomain;
  * @name: Powerdomain name
  * @voltdm: voltagedomain containing this powerdomain
  * @prcm_offs: the address offset from CM_BASE/PRM_BASE
+ * @context_offs: the address offset for the CONTEXT register
  * @prcm_partition: (OMAP4 only) the PRCM partition ID containing @prcm_offs
  * @pwrsts: Possible powerdomain power states
  * @pwrsts_logic_ret: Possible logic power states when pwrdm in RETENTION
@@ -106,6 +107,7 @@ struct powerdomain {
 		struct voltagedomain *ptr;
 	} voltdm;
 	const s16 prcm_offs;
+	const s16 context_offs;
 	const u8 pwrsts;
 	const u8 pwrsts_logic_ret;
 	const u8 flags;
diff --git a/arch/arm/mach-omap2/powerdomains44xx_data.c b/arch/arm/mach-omap2/powerdomains44xx_data.c
index d8701ce..c4de02f 100644
--- a/arch/arm/mach-omap2/powerdomains44xx_data.c
+++ b/arch/arm/mach-omap2/powerdomains44xx_data.c
@@ -36,6 +36,7 @@ static struct powerdomain core_44xx_pwrdm = {
 	.voltdm		  = { .name = "core" },
 	.prcm_offs	  = OMAP4430_PRM_CORE_INST,
 	.prcm_partition	  = OMAP4430_PRM_PARTITION,
+	.context_offs	  = OMAP4_RM_L3_1_L3_1_CONTEXT_OFFSET,
 	.pwrsts		  = PWRSTS_RET_ON,
 	.pwrsts_logic_ret = PWRSTS_OFF_RET,
 	.banks		  = 5,
@@ -205,6 +206,7 @@ static struct powerdomain mpu_44xx_pwrdm = {
 	.voltdm		  = { .name = "mpu" },
 	.prcm_offs	  = OMAP4430_PRM_MPU_INST,
 	.prcm_partition	  = OMAP4430_PRM_PARTITION,
+	.context_offs	  = OMAP4_RM_MPU_MPU_CONTEXT_OFFSET,
 	.pwrsts		  = PWRSTS_RET_ON,
 	.pwrsts_logic_ret = PWRSTS_OFF_RET,
 	.banks		  = 3,
diff --git a/arch/arm/mach-omap2/prm44xx.c b/arch/arm/mach-omap2/prm44xx.c
index 86c6c6b..de9132f 100644
--- a/arch/arm/mach-omap2/prm44xx.c
+++ b/arch/arm/mach-omap2/prm44xx.c
@@ -289,6 +289,21 @@ static void __init omap44xx_prm_enable_io_wakeup(void)
 			OMAP4_PRM_IO_PMCTRL_OFFSET);
 }
 
+bool omap4_pwrdm_lost_context_rff(s16 inst, s16 offset)
+{
+	u32 val;
+
+	val = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION, inst, offset);
+
+	if (val & OMAP4430_LOSTCONTEXT_RFF_MASK) {
+		omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION, inst,
+					     offset);
+		return true;
+	}
+
+	return false;
+}
+
 /**
  * omap4_device_set_state_off() - setup device off state
  * @enable:	set to off or not.
diff --git a/arch/arm/mach-omap2/prm44xx.h b/arch/arm/mach-omap2/prm44xx.h
index ee72ae6..fa76d9c 100644
--- a/arch/arm/mach-omap2/prm44xx.h
+++ b/arch/arm/mach-omap2/prm44xx.h
@@ -771,6 +771,8 @@ extern void omap44xx_prm_ocp_barrier(void);
 extern void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask);
 extern void omap44xx_prm_restore_irqen(u32 *saved_mask);
 
+extern bool omap4_pwrdm_lost_context_rff(s16 inst, s16 offset);
+
 # endif
 
 #endif
-- 
1.7.4.1