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

Troy Kisky
2015-02-05T23:06:56Z

On 2/5/2015 3:58 PM, Eric Nelson wrote:
> 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";

Instead of removing default, can we have a hex value, something like
sprintf(buf, "unknown(0x%x)", cause);

> }
> + setenv("reset_cause", rval);
> + return rval;
> }
>
> #if defined(CONFIG_MX53) || defined(CONFIG_MX6)
>