mpc83xx: Add support for the display of reset status

From: Dave Liu <[email protected]>

83xx processor family has many reset sources, such as power on reset, software hard reset, software soft reset, JTAG, bus monitor, software watchdog, check stop reset, external hard reset, external software reset. sometimes, to figure out the fault of system, we need to know the cause of reset early before the prompt of u-boot present.

Signed-off-by Dave Liu <[email protected]>

---
 cpu/mpc83xx/cpu_init.c |   36 ++++++++++++++++++++++++++++++++++++
 include/common.h       |    2 ++
 lib_ppc/board.c        |    6 ++++--
 3 files changed, 42 insertions(+), 2 deletions(-)

cpu/mpc83xx/cpu_init.c +36 -0

index 3ac9161..46a6300 100644
@@ -247,3 +247,39 @@ int cpu_init_r (void)
 #endif
 	return 0;
 }
+
+/*
+ * Figure out the cause of the reset
+ */
+int prt_83xx_rsr(void)
+{
+	static struct {
+		ulong mask;
+		char *desc;
+	} bits[] = {
+		{
+		RSR_SWSR, "Software Soft"}, {
+		RSR_SWHR, "Software Hard"}, {
+		RSR_JSRS, "JTAG Soft"}, {
+		RSR_CSHR, "Check Stop"}, {
+		RSR_SWRS, "Software Watchdog"}, {
+		RSR_BMRS, "Bus Monitor"}, {
+		RSR_SRS,  "External/Internal Soft"}, {
+		RSR_HRS,  "External/Internal Hard"}
+	};
+	static int n = sizeof bits / sizeof bits[0];
+	ulong rsr = gd->reset_status;
+	int i;
+	char *sep;
+	
+	puts("Reset Status:");
+
+	sep = " ";
+	for (i = 0; i < n; i++)
+		if (rsr & bits[i].mask) {
+			printf("%s%s", sep, bits[i].desc);
+			sep = ", ";
+		}
+	puts("\n\n");
+	return 0;
+}

include/common.h +2 -0

index 3c4b37b..a710d38 100644
@@ -511,6 +511,8 @@ void	cpu_init_f    (void);
 int	cpu_init_r    (void);
 #if defined(CONFIG_8260)
 int	prt_8260_rsr  (void);
+#elif defined(CONFIG_MPC83XX)
+int	prt_83xx_rsr  (void);
 #endif
 
 /* $(CPU)/interrupts.c */

lib_ppc/board.c +4 -2

index c4fc580..fea9bf8 100644
@@ -309,7 +309,9 @@ init_fnc_t *init_sequence[] = {
 	prt_8260_rsr,
 	prt_8260_clks,
 #endif /* CONFIG_8260 */
-
+#if defined(CONFIG_MPC83XX)
+	prt_83xx_rsr,
+#endif
 	checkcpu,
 #if defined(CONFIG_MPC5xxx)
 	prt_mpc5xxx_clks,

@@ -376,7 +378,7 @@ void board_init_f (ulong bootflag)
 	/* compiler optimization barrier needed for GCC >= 3.4 */
 	__asm__ __volatile__("": : :"memory");
 
-#if !defined(CONFIG_CPM2)
+#if !defined(CONFIG_CPM2) && !defined(CONFIG_MPC83XX)
 	/* Clear initial global data */
 	memset ((void *) gd, 0, sizeof (gd_t));
 #endif

Quoted 7 lines

83xx processor family has many reset sources, such as power on reset, software hard reset, software soft reset, JTAG, bus monitor, software watchdog, check stop reset, external hard reset, external software reset. sometimes, to figure out the fault of system, we need to know the cause of reset early before the prompt of u-boot present.

How do you detect power on reset? I have looked for that but the rsr reg does not seem to support that and I really want to detect this.

Quoted 8 lines

Quoted 7 lines

83xx processor family has many reset sources, such as power on reset, software hard reset, software soft reset, JTAG, bus monitor, software watchdog, check stop reset, external hard reset, external software reset. sometimes, to figure out the fault of system, we need to know the cause of reset early before the prompt of u-boot present.

Quoted 3 lines

How do you detect power on reset? I have looked for that but the rsr reg does not seem to support that and I really want to detect this.

Usually, if all of these status bits of rsr is zero, consider this as power on reset.