[U-Boot] [PATCH] imx: save reset cause in 'reset_cause' environment variable

Eric Nelson
2015-02-05T22:58:27Z

The cause of a reset is generally useful, and shouldn't be
blindly cleared in the process of displaying it as a part
of the boot announcement.

Stash the string representation in the environment variable
"reset_cause".

Values include:
"POR" - power on reset
"CSU" - reset was the result of the csu_reset_b input
"IPP-USER" - ipp_user_reset_b qualified reset
"WDOG" - watchdog reset
"JTAG-HIGH-Z" - HIGH-Z reset from JTAG
"JTAG-SW" - software reset from JTAG
"WARM-BOOT" - WARM boot was initiated by software

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
---
arch/arm/imx-common/cpu.c | 25 ++++++++++++++++---------
1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/arm/imx-common/cpu.c b/arch/arm/imx-common/cpu.c
index 28ccd29..4a54051 100644
--- a/arch/arm/imx-common/cpu.c
+++ b/arch/arm/imx-common/cpu.c
@@ -28,6 +28,7 @@ char *get_reset_cause(void)
{
u32 cause;
struct src *src_regs = (struct src *)SRC_BASE_ADDR;
+ char *rval = "unknown";

cause = readl(&src_regs->srsr);
writel(cause, &src_regs->srsr);
@@ -35,22 +36,28 @@ char *get_reset_cause(void)
switch (cause) {
case 0x00001:
case 0x00011:
- return "POR";
+ rval = "POR";
+ break;
case 0x00004:
- return "CSU";
+ rval = "CSU";
+ break;
case 0x00008:
- return "IPP USER";
+ rval = "IPP-USER";
+ break;
case 0x00010:
- return "WDOG";
+ rval = "WDOG";
+ break;
case 0x00020:
- return "JTAG HIGH-Z";
+ rval = "JTAG-HIGH-Z";
+ break;
case 0x00040:
- return "JTAG SW";
+ rval = "JTAG-SW";
+ break;
case 0x10000:
- return "WARM BOOT";
- default:
- return "unknown reset";
+ rval = "WARM-BOOT";
}
+ setenv("reset_cause", rval);
+ return rval;
}

#if defined(CONFIG_MX53) || defined(CONFIG_MX6)
--
1.9.1