msm: rtb: Log the context id in the rtb

Store the context id in the register trace buffer.
The process id can be derived from the context id.
This gives a general idea about what process was last
running when the RTB stopped.

Change-Id: I2fb8934d008b8cf3666f1df2652846c15faca776
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 14536f6..946899d 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -17,6 +17,8 @@
 #include <asm/thread_notify.h>
 #include <asm/tlbflush.h>
 
+#include <mach/msm_rtb.h>
+
 static DEFINE_RAW_SPINLOCK(cpu_asid_lock);
 unsigned int cpu_last_asid = ASID_FIRST_VERSION;
 #ifdef CONFIG_SMP
@@ -25,6 +27,7 @@
 
 static void write_contextidr(u32 contextidr)
 {
+	uncached_logk(LOGK_CTXID, (void *)contextidr);
 	asm("mcr	p15, 0, %0, c13, c0, 1" : : "r" (contextidr));
 	isb();
 }