[PATCH v2 2/2] watchdog: mtk_wdt: Add reset_by_toprgu support

[Guenter Roeck]

On 1/16/23 02:53, Allen-KH Cheng wrote:
> In some cases, the MediaTek watchdog requires the toprgu to reset
> timer after system resets.
> 
> Provide a reset_by_toprgu parameter for configuration.
> 
> Signed-off-by: Allen-KH Cheng <allen-kh.cheng at mediatek.com>

Reviewed-by: Guenter Roeck <linux at roeck-us.net>

> ---
>   drivers/watchdog/mtk_wdt.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
> index 3e6212591e69..a9c437598e7e 100644
> --- a/drivers/watchdog/mtk_wdt.c
> +++ b/drivers/watchdog/mtk_wdt.c
> @@ -50,6 +50,7 @@
>   #define WDT_MODE_IRQ_EN		(1 << 3)
>   #define WDT_MODE_AUTO_START	(1 << 4)
>   #define WDT_MODE_DUAL_EN	(1 << 6)
> +#define WDT_MODE_CNT_SEL	(1 << 8)
>   #define WDT_MODE_KEY		0x22000000
>   
>   #define WDT_SWRST		0x14
> @@ -70,6 +71,7 @@ struct mtk_wdt_dev {
>   	spinlock_t lock; /* protects WDT_SWSYSRST reg */
>   	struct reset_controller_dev rcdev;
>   	bool disable_wdt_extrst;
> +	bool reset_by_toprgu;
>   };
>   
>   struct mtk_wdt_data {
> @@ -279,6 +281,8 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
>   		reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
>   	if (mtk_wdt->disable_wdt_extrst)
>   		reg &= ~WDT_MODE_EXRST_EN;
> +	if (mtk_wdt->reset_by_toprgu)
> +		reg |= WDT_MODE_CNT_SEL;
>   	reg |= (WDT_MODE_EN | WDT_MODE_KEY);
>   	iowrite32(reg, wdt_base + WDT_MODE);
>   
> @@ -408,6 +412,9 @@ static int mtk_wdt_probe(struct platform_device *pdev)
>   	mtk_wdt->disable_wdt_extrst =
>   		of_property_read_bool(dev->of_node, "mediatek,disable-extrst");
>   
> +	mtk_wdt->reset_by_toprgu =
> +		of_property_read_bool(dev->of_node, "mediatek,reset-by-toprgu");
> +
>   	return 0;
>   }
>