Re: [PATCH v2 2/2] watchdog: s3c2410_wdt: Report when the watchdog reset the system

Guenter Roeck
2013-12-06T19:54:23Z

On Thu, Dec 05, 2013 at 10:15:29AM -0800, Doug Anderson wrote:
> A good watchdog driver is supposed to report when it was responsible
> for resetting the system. Implement this for the s3c2410, at least on
> exynos5250 and exynos5420 where we already have a pointer to the PMU
> registers to read the information.
>
> Note that exynos4 SoCs also provide the reset status, but providing
> that is left as an exercise for future changes and is not plumbed up
> in this patch series. Also note the exynos4 SoCs don't appear to need
> any PMU config, which is why this patch separates the concepts of
> having PMU Registers vs. needing PMU Config.
>
> Signed-off-by: Doug Anderson <dianders@chromium.org>
> ---
> Changes in v2:
> - Explained QUIRK organization in patch descritpion.
> - Reduced indentation as per Olof and Tomasz suggestion.
> - Now atop proposed v12 of Leela Krishna's patches.

Hi Doug,

The patch doesn't apply on top of v12, unfortunately.

> - NEEDS => HAS, EXYNOS5 prefix
>
> drivers/watchdog/s3c2410_wdt.c | 42 +++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 39 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
> index 6a00299..45a9503 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
> @@ -62,9 +62,15 @@
> #define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
> #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
>
> +#define EXYNOS5_RST_STAT_REG_OFFSET 0x0404
> #define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
> #define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
> #define QUIRK_HAS_PMU_CONFIG (1 << 0)
> +#define QUIRK_HAS_RST_STAT (1 << 1)
> +
> +/* These quirks require that we have a PMU register map */
> +#define QUIRKS_HAVE_PMUREG (QUIRK_HAS_PMU_CONFIG | \
> + QUIRK_HAS_RST_STAT)
>
> static bool nowayout = WATCHDOG_NOWAYOUT;
> static int tmr_margin;
> @@ -98,6 +104,9 @@ MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
> * timer reset functionality.
> * @mask_bit: Bit number for the watchdog timer in the disable register and the
> * mask reset register.
> + * @rst_stat_reg: Offset in pmureg for the register that has the reset status.
> + * @rst_stat_bit: Bit number in the rst_stat register indicating a watchdog
> + * reset.
> * @quirks: A bitfield of quirks.
> */
>
> @@ -105,6 +114,8 @@ struct s3c2410_wdt_variant {
> int disable_reg;
> int mask_reset_reg;
> int mask_bit;
> + int rst_stat_reg;
> + int rst_stat_bit;
> u32 quirks;
> };
>
> @@ -131,14 +142,20 @@ static const struct s3c2410_wdt_variant drv_data_exynos5250 = {
> .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
> .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
> .mask_bit = 20,
> - .quirks = QUIRK_HAS_PMU_CONFIG
> + .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
> + .rst_stat_bit = 20,
> + .quirks = QUIRK_HAS_PMU_CONFIG |
> + QUIRK_HAS_RST_STAT,

Any reason not to use QUIRKS_HAVE_PMUREG ?

> };
>
> static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
> .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
> .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
> .mask_bit = 0,
> - .quirks = QUIRK_HAS_PMU_CONFIG
> + .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
> + .rst_stat_bit = 9,
> + .quirks = QUIRK_HAS_PMU_CONFIG |
> + QUIRK_HAS_RST_STAT,

Same here. Even if you don't use QUIRKS_HAVE_PMUREG, the continuation line is not needed.

Thanks,
Guenter