[PATCH v3 1/3] watchdog: mtk_wdt: Refactor code to support more SoCs

Guenter Roeck linux at roeck-us.net
Thu May 13 08:22:40 PDT 2021


On Thu, May 13, 2021 at 04:35:13AM +0300, Boris Lysov wrote:
> This patch makes some constants SoC-dependent to support more watchdogs
> in the future. It adds shifts of WDT_MODE_KEY and SWSYSRST_KEY to
> mtk_wdt_data struct. This is done to bring support for various Mediatek
> watchdogs which use same register structure but slightly different field
> offsets in the UNLOCK_KEY registers. For example, mt6577 watchdog has
> WDT_MODE_KEY and SWSYSRST_KEY at [15:8] instead of currently (and only)
> supported [31:24].
> Moreover, this patch adds SWSYSRST_KEY value to mtk_wdt_data because this
> value also depends on specific SoC watchdog, for example mt6577 uses 0x15
> instead of 0x88.
> 
> Signed-off-by: Boris Lysov <arzamas-16 at mail.ee>

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

> ---
> Changes since v2 [3]:
> - rename the newly introduced structure element ('data' -> 'config') to
>   avoid changing the names of already existing variables; suggested [4]
>   by Guenter Roeck.
> 
> Changes since v1 [1]:
> - a complete rewrite to get rid of the configuration flags which made
>   the watchdog not support other SoCs; suggested [2] by Guenter Roeck.
> 
> [1] https://lore.kernel.org/linux-mediatek/20210131234425.9773-3-arzamas-16@mail.ee/
> [2] https://lore.kernel.org/linux-mediatek/050f2f8e-9c3c-10e3-05ef-cd84e949b98f@roeck-us.net/
> [3] https://lore.kernel.org/linux-mediatek/20210509211702.549-2-arzamas-16@mail.ee/
> [4] https://lore.kernel.org/linux-mediatek/efdce3a5-e5b4-19a8-35f1-8a536220bb3f@roeck-us.net/
> 
>  drivers/watchdog/mtk_wdt.c | 66 ++++++++++++++++++++++++++++++--------
>  1 file changed, 52 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
> index 97ca993bd009..0878fa33dffe 100644
> --- a/drivers/watchdog/mtk_wdt.c
> +++ b/drivers/watchdog/mtk_wdt.c
> @@ -44,13 +44,27 @@
>  #define WDT_MODE_IRQ_EN		(1 << 3)
>  #define WDT_MODE_AUTO_START	(1 << 4)
>  #define WDT_MODE_DUAL_EN	(1 << 6)
> -#define WDT_MODE_KEY		0x22000000
> +#define WDT_MODE_KEY		0x22
>  
>  #define WDT_SWRST		0x14
>  #define WDT_SWRST_KEY		0x1209
> -
>  #define WDT_SWSYSRST		0x18U
> -#define WDT_SWSYS_RST_KEY	0x88000000
> +
> +#define MT2712_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT2712_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT2712_SWSYSRST_KEY		0x88
> +
> +#define MT6589_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT6589_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT6589_SWSYSRST_KEY		0x88
> +
> +#define MT8183_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT8183_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT8183_SWSYSRST_KEY		0x88
> +
> +#define MT8192_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT8192_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
> +#define MT8192_SWSYSRST_KEY		0x88
>  
>  #define DRV_NAME		"mtk-wdt"
>  #define DRV_VERSION		"1.0"
> @@ -60,6 +74,7 @@ static unsigned int timeout;
>  
>  struct mtk_wdt_dev {
>  	struct watchdog_device wdt_dev;
> +	const struct mtk_wdt_data *config;
>  	void __iomem *wdt_base;
>  	spinlock_t lock; /* protects WDT_SWSYSRST reg */
>  	struct reset_controller_dev rcdev;
> @@ -67,18 +82,37 @@ struct mtk_wdt_dev {
>  
>  struct mtk_wdt_data {
>  	int toprgu_sw_rst_num;
> +	u8 wdt_mode_key_shift;
> +	u8 wdt_swsys_rst_key;
> +	u8 wdt_swsys_rst_key_shift;
>  };
>  
>  static const struct mtk_wdt_data mt2712_data = {
> -	.toprgu_sw_rst_num = MT2712_TOPRGU_SW_RST_NUM,
> +	.toprgu_sw_rst_num =		MT2712_TOPRGU_SW_RST_NUM,
> +	.wdt_mode_key_shift =		MT2712_WDT_MODE_KEY_SHIFT,
> +	.wdt_swsys_rst_key_shift =	MT2712_SWSYSRST_KEY_SHIFT,
> +	.wdt_swsys_rst_key =		MT2712_SWSYSRST_KEY,
> +};
> +
> +static const struct mtk_wdt_data mt6589_data = {
> +	.toprgu_sw_rst_num =		-1,
> +	.wdt_mode_key_shift =		MT6589_WDT_MODE_KEY_SHIFT,
> +	.wdt_swsys_rst_key_shift =	MT6589_SWSYSRST_KEY_SHIFT,
> +	.wdt_swsys_rst_key =		MT6589_SWSYSRST_KEY,
>  };
>  
>  static const struct mtk_wdt_data mt8183_data = {
> -	.toprgu_sw_rst_num = MT8183_TOPRGU_SW_RST_NUM,
> +	.toprgu_sw_rst_num =		MT8183_TOPRGU_SW_RST_NUM,
> +	.wdt_mode_key_shift =		MT8183_WDT_MODE_KEY_SHIFT,
> +	.wdt_swsys_rst_key_shift =	MT8183_SWSYSRST_KEY_SHIFT,
> +	.wdt_swsys_rst_key =		MT8183_SWSYSRST_KEY,
>  };
>  
>  static const struct mtk_wdt_data mt8192_data = {
> -	.toprgu_sw_rst_num = MT8192_TOPRGU_SW_RST_NUM,
> +	.toprgu_sw_rst_num =		MT8192_TOPRGU_SW_RST_NUM,
> +	.wdt_mode_key_shift =		MT8192_WDT_MODE_KEY_SHIFT,
> +	.wdt_swsys_rst_key_shift =	MT8192_SWSYSRST_KEY_SHIFT,
> +	.wdt_swsys_rst_key =		MT8192_SWSYSRST_KEY,
>  };
>  
>  static int toprgu_reset_update(struct reset_controller_dev *rcdev,
> @@ -96,7 +130,7 @@ static int toprgu_reset_update(struct reset_controller_dev *rcdev,
>  		tmp |= BIT(id);
>  	else
>  		tmp &= ~BIT(id);
> -	tmp |= WDT_SWSYS_RST_KEY;
> +	tmp |= data->config->wdt_swsys_rst_key << data->config->wdt_swsys_rst_key_shift;
>  	writel(tmp, data->wdt_base + WDT_SWSYSRST);
>  
>  	spin_unlock_irqrestore(&data->lock, flags);
> @@ -221,7 +255,7 @@ static int mtk_wdt_stop(struct watchdog_device *wdt_dev)
>  
>  	reg = readl(wdt_base + WDT_MODE);
>  	reg &= ~WDT_MODE_EN;
> -	reg |= WDT_MODE_KEY;
> +	reg |= WDT_MODE_KEY << mtk_wdt->config->wdt_mode_key_shift;
>  	iowrite32(reg, wdt_base + WDT_MODE);
>  
>  	return 0;
> @@ -240,7 +274,7 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
>  
>  	reg = ioread32(wdt_base + WDT_MODE);
>  	reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
> -	reg |= (WDT_MODE_EN | WDT_MODE_KEY);
> +	reg |= (WDT_MODE_EN | (WDT_MODE_KEY << mtk_wdt->config->wdt_mode_key_shift));
>  	iowrite32(reg, wdt_base + WDT_MODE);
>  
>  	return 0;
> @@ -266,7 +300,6 @@ static int mtk_wdt_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct mtk_wdt_dev *mtk_wdt;
> -	const struct mtk_wdt_data *wdt_data;
>  	int err;
>  
>  	mtk_wdt = devm_kzalloc(dev, sizeof(*mtk_wdt), GFP_KERNEL);
> @@ -279,6 +312,12 @@ static int mtk_wdt_probe(struct platform_device *pdev)
>  	if (IS_ERR(mtk_wdt->wdt_base))
>  		return PTR_ERR(mtk_wdt->wdt_base);
>  
> +	mtk_wdt->config = of_device_get_match_data(dev);
> +	if (!mtk_wdt->config) {
> +		dev_err(dev, "watchdog data is not defined\n");
> +		return -EINVAL;
> +	}
> +
>  	mtk_wdt->wdt_dev.info = &mtk_wdt_info;
>  	mtk_wdt->wdt_dev.ops = &mtk_wdt_ops;
>  	mtk_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
> @@ -302,10 +341,9 @@ static int mtk_wdt_probe(struct platform_device *pdev)
>  	dev_info(dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)\n",
>  		 mtk_wdt->wdt_dev.timeout, nowayout);
>  
> -	wdt_data = of_device_get_match_data(dev);
> -	if (wdt_data) {
> +	if (mtk_wdt->config->toprgu_sw_rst_num > -1) {
>  		err = toprgu_register_reset_controller(pdev,
> -						       wdt_data->toprgu_sw_rst_num);
> +						       mtk_wdt->config->toprgu_sw_rst_num);
>  		if (err)
>  			return err;
>  	}
> @@ -338,7 +376,7 @@ static int mtk_wdt_resume(struct device *dev)
>  
>  static const struct of_device_id mtk_wdt_dt_ids[] = {
>  	{ .compatible = "mediatek,mt2712-wdt", .data = &mt2712_data },
> -	{ .compatible = "mediatek,mt6589-wdt" },
> +	{ .compatible = "mediatek,mt6589-wdt", .data = &mt6589_data },
>  	{ .compatible = "mediatek,mt8183-wdt", .data = &mt8183_data },
>  	{ .compatible = "mediatek,mt8192-wdt", .data = &mt8192_data },
>  	{ /* sentinel */ }
> -- 
> 2.20.1
> 



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