On 12/01/2023, Peter Griffin wrote:
> The WDT uses the CPU core signal DBGACK to determine whether the SoC
> is running in debug mode or not. If the DBGACK signal is asserted and
> DBGACK_MASK bit is enabled, then WDT output and interrupt is masked
> (disabled).
>
> Presence of the DBGACK_MASK bit is determined by adding a new
> QUIRK_HAS_DBGACK_BIT quirk.
>
> Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
Tested-by: Will McVicker <willmcvicker@xxxxxxxxxx>
---
I verified boot to a busybox console and that the watchdog probes.
Regards,
Will
> ---
> drivers/watchdog/s3c2410_wdt.c | 27 ++++++++++++++++++++++++---
> 1 file changed, 24 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
> index 0b4bd883ff28..39f3489e41d6 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
> @@ -34,9 +34,10 @@
>
> #define S3C2410_WTCNT_MAXCNT 0xffff
>
> -#define S3C2410_WTCON_RSTEN (1 << 0)
> -#define S3C2410_WTCON_INTEN (1 << 2)
> -#define S3C2410_WTCON_ENABLE (1 << 5)
> +#define S3C2410_WTCON_RSTEN (1 << 0)
> +#define S3C2410_WTCON_INTEN (1 << 2)
> +#define S3C2410_WTCON_ENABLE (1 << 5)
> +#define S3C2410_WTCON_DBGACK_MASK (1 << 16)
>
> #define S3C2410_WTCON_DIV16 (0 << 3)
> #define S3C2410_WTCON_DIV32 (1 << 3)
> @@ -100,12 +101,17 @@
> * %QUIRK_HAS_PMU_CNT_EN: PMU block has some register (e.g. CLUSTERx_NONCPU_OUT)
> * with "watchdog counter enable" bit. That bit should be set to make watchdog
> * counter running.
> + *
> + * %QUIRK_HAS_DBGACK_BIT: WTCON register has DBGACK_MASK bit. Setting the
> + * DBGACK_MASK bit disables the watchdog outputs when the SoC is in debug mode.
> + * Debug mode is determined by the DBGACK CPU signal.
> */
> #define QUIRK_HAS_WTCLRINT_REG (1 << 0)
> #define QUIRK_HAS_PMU_MASK_RESET (1 << 1)
> #define QUIRK_HAS_PMU_RST_STAT (1 << 2)
> #define QUIRK_HAS_PMU_AUTO_DISABLE (1 << 3)
> #define QUIRK_HAS_PMU_CNT_EN (1 << 4)
> +#define QUIRK_HAS_DBGACK_BIT (1 << 5)
>
> /* These quirks require that we have a PMU register map */
> #define QUIRKS_HAVE_PMUREG \
> @@ -375,6 +381,19 @@ static int s3c2410wdt_enable(struct s3c2410_wdt *wdt, bool en)
> return 0;
> }
>
> +static void s3c2410wdt_mask_dbgack(struct s3c2410_wdt *wdt)
> +{
> + unsigned long wtcon;
> +
> + if (!(wdt->drv_data->quirks & QUIRK_HAS_DBGACK_BIT))
> + return;
> +
> + /* disable watchdog outputs if CPU is in debug mode */
> + wtcon = readl(wdt->reg_base + S3C2410_WTCON);
> + wtcon |= S3C2410_WTCON_DBGACK_MASK;
> + writel(wtcon, wdt->reg_base + S3C2410_WTCON);
> +}
> +
> static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
> {
> struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
> @@ -700,6 +719,8 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
> wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
> wdt->wdt_device.parent = dev;
>
> + s3c2410wdt_mask_dbgack(wdt);
> +
> /*
> * If "tmr_atboot" param is non-zero, start the watchdog right now. Also
> * set WDOG_HW_RUNNING bit, so that watchdog core can kick the watchdog.
> --
> 2.43.0.rc2.451.g8631bc7472-goog
>
