ux500: sw reset: Save SW Reset Reason before reset

Converts the reboot reason string received in SYSCALL_DEFINE4 in
sys.c into a 2 bytes reset reason code. This 16 bit value is
stored in the TCDM Memory at location: tcdm_base + 0xFF8.

The string to code mapping structure has been added in file
reboot_reasons.h and reboot_reasons.c. The code for translation
has been placed in cpu.c.

ST-Ericsson Linux next: Tested and reviewed with 2011-03-28
ST-Ericsson ID: 327863
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: I5fe83b824c6dbe3f61a3d77671ce845e6f81d87b
Signed-off-by: rickard evertsson <rickard.evertsson@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/19174
Reviewed-by: Mattias WALLIN <mattias.wallin@stericsson.com>

Conflicts:

	arch/arm/mach-ux500/Makefile
	arch/arm/mach-ux500/cpu.c

1 files changed, 30 insertions, 1 deletions

diff --git a/arch/arm/mach-ux500/cpu.c b/arch/arm/mach-ux500/cpu.c
index d8a62845791..3d4ceed17e3 100644
--- a/arch/arm/mach-ux500/cpu.c
+++ b/arch/arm/mach-ux500/cpu.c
@@ -24,6 +24,7 @@
 #include <mach/devices.h>
 #include <mach/prcmu-fw-api.h>
 #include <mach/prcmu-db5500.h>
+#include <mach/reboot_reasons.h>
 
 #include "clock.h"
 
@@ -33,9 +34,37 @@ void __iomem *_PRCMU_BASE;
 static void __iomem *l2x0_base;
 #endif
 
+/*
+ * The reboot reason string can be 255 characters long and the memory
+ * in which we save the sw reset reason is 2 bytes. Therefore we need to
+ * convert the string into a 16 bit pattern.
+ *
+ * See file reboot_reasons.h for conversion.
+ */
+static unsigned short map_cmd_to_code(const char *cmd)
+{
+	int i;
+
+	if (cmd == NULL)
+		/* normal reboot w/o argument */
+		return SW_RESET_NO_ARGUMENT;
+
+	/* Search through reboot reason list */
+	for (i = 0; i < reboot_reasons_size; i++) {
+		if (!strcmp(reboot_reasons[i].reason, cmd))
+			return reboot_reasons[i].code;
+	}
+
+	/* No valid Reboot Reason found */
+	return SW_RESET_CRASH;
+}
+
 static void ux500_restart(char mode, const char *cmd)
 {
-	prcmu_system_reset();
+	unsigned short reset_code;
+
+	reset_code = map_cmd_to_code(cmd);
+	prcmu_system_reset(reset_code);
 
 	mdelay(1000);
 	printk("Reboot via PRCMU failed -- System halted\n");