[U-Boot] [PATCH v4 2/3] MX31: Introduce get_reset_cause()

[Fabio Estevam <festevam@gmail.com>]

Introduce get_reset_cause() function to indicate the source of the reset.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
 arch/arm/cpu/arm1136/mx31/generic.c        |   26 +++++++++++++++++++++++++
 arch/arm/include/asm/arch-mx31/sys_proto.h |   29 ++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/include/asm/arch-mx31/sys_proto.h

diff --git a/arch/arm/cpu/arm1136/mx31/generic.c b/arch/arm/cpu/arm1136/mx31/generic.c
index 9b7a7a2..ea452a9 100644
--- a/arch/arm/cpu/arm1136/mx31/generic.c
+++ b/arch/arm/cpu/arm1136/mx31/generic.c
@@ -132,6 +132,32 @@ char *get_cpu_rev(void)
 		return "unknown";
 }
 
+char *get_reset_cause(void)
+{
+	/* read SRS register from CCM module */
+	struct clock_control_regs *ccm =
+		(struct clock_control_regs *)CCM_BASE;
+
+	u32 cause = readl(&ccm->rcsr) & 0x07;
+
+	switch (cause) {
+	case 0x0000:
+		return "POR";
+		break;
+	case 0x0001:
+		return "RST";
+		break;
+	case 0x0002:
+		return "WDOG";
+		break;
+	case 0x0006:
+		return "JTAG";
+		break;
+	default:
+		return "unknown reset";
+	}
+}
+
 #if defined(CONFIG_DISPLAY_CPUINFO)
 int print_cpuinfo (void)
 {
diff --git a/arch/arm/include/asm/arch-mx31/sys_proto.h b/arch/arm/include/asm/arch-mx31/sys_proto.h
new file mode 100644
index 0000000..7a0d03f
--- /dev/null
+++ b/arch/arm/include/asm/arch-mx31/sys_proto.h
@@ -0,0 +1,29 @@
+/*
+ * (C) Copyright 2011
+ * Stefano Babic, DENX Software Engineering, sbabic at denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _SYS_PROTO_H_
+#define _SYS_PROTO_H_
+
+extern char *get_reset_cause(void);
+
+#endif
-- 
1.6.0.4