msm: pm: warmboot entry/exit counters on IMEM

Add warmboot entry/exit counters for each core on a non-cacheable always
on IMEM memory. This is a useful feature during debug to understand if
the system has correctly warmbooted after a power collapse. The debug
counters start at a memory offset of 0x664 on the IMEM. Each core
reserves 4 words for events, of which 3 are being used to monitor the
following events,
1) power collapse entry
2) warmboot exit
3) failed power collapse when wfi returns with a pending interrupt.

Change-Id: I45aac8e4a4d3421d586790b3b66fd71a8d88ea9d
Signed-off-by: Mahesh Sivasubramanian <msivasub@codeaurora.org>
diff --git a/arch/arm/mach-msm/idle-v7.S b/arch/arm/mach-msm/idle-v7.S
index f970769..1d8f313 100644
--- a/arch/arm/mach-msm/idle-v7.S
+++ b/arch/arm/mach-msm/idle-v7.S
@@ -128,6 +128,19 @@
 	bne	skip
 	bl	v7_flush_dcache_all
 skip:
+	mrc	p15, 0, r0, c0, c0, 5	/* MPIDR */
+	and	r0, r0, #15		/* what CPU am I */
+
+	ldr	r1, =msm_pc_debug_counters /*load the IMEM debug location */
+	ldr	r1, [r1]
+	cmp	r1, #0
+	beq	skip_pc_debug1
+	add	r1, r1, r0, LSL #4	/* debug location for this CPU */
+	ldr	r2, [r1]
+	add	r2, #1
+	str	r2, [r1]
+skip_pc_debug1:
+
 #ifdef CONFIG_ARCH_MSM_KRAIT
 	ldr	r0, =SCM_SVC_BOOT
 	ldr	r1, =SCM_CMD_TERMINATE_PC
@@ -155,6 +168,21 @@
 #if defined(CONFIG_MSM_FIQ_SUPPORT)
 	cpsie   f
 #endif
+	mrc	p15, 0, r0, c0, c0, 5 /* MPIDR */
+	and	r0, r0, #15              /* what CPU am I                  */
+
+	ldr	r1, =msm_pc_debug_counters /*load the IMEM debug location */
+	ldr	r1, [r1]
+	cmp	r1, #0
+	beq	skip_pc_debug2
+	add	r1, r1, r0, LSL #4	/* debug location for this CPU */
+	add	r1, #8
+	ldr	r2, [r1]
+	add	r2, #1
+	str	r2, [r1]
+
+skip_pc_debug2:
+
 #ifdef CONFIG_MSM_JTAG
 	bl	msm_jtag_restore_state
 #endif
@@ -276,6 +304,22 @@
 	mrc     p15, 0, r0, c0, c0, 5    /* MPIDR                          */
 	and     r0, r0, #15              /* what CPU am I                  */
 
+	ldr	r1, =msm_pc_debug_counters_phys /*phys addr for IMEM reg */
+	ldr	r2, =msm_pm_boot_entry
+	adr	r3, msm_pm_boot_entry
+	add	r1, r1, r3               /* translate virt to phys addr    */
+	sub	r1, r1, r2
+	ldr	r1,[r1]
+
+	cmp	r1, #0
+	beq	skip_pc_debug3
+	add	r1, r1, r0, LSL #4	/* debug location for this CPU */
+	add	r1, #4			/* warmboot entry counter*/
+	ldr	r2, [r1]
+	add	r2, #1
+	str	r2, [r1]
+
+skip_pc_debug3:
 	ldr     r1, =msm_pm_boot_vector
 	ldr     r2, =msm_pm_boot_entry
 	adr     r3, msm_pm_boot_entry
@@ -325,6 +369,14 @@
 l2x0_base_addr:
 	.long 0x0
 
+	.globl msm_pc_debug_counters_phys
+msm_pc_debug_counters_phys:
+	.long 0x0
+
+	.globl msm_pc_debug_counters
+msm_pc_debug_counters:
+	.long 0x0
+
 /*
  * Default the l2 flush flag to 1 so that caches are flushed during power
  * collapse unless the  L2 driver decides to flush them only during L2