diff mbox series

[v4,2/2] watchdog: rzg2l_wdt: Add rzv2m support

Message ID 20220823093233.8577-3-phil.edworthy@renesas.com (mailing list archive)
State Accepted
Delegated to: Geert Uytterhoeven
Headers show
Series arm64: renesas: Add RZ/V2M watchdog support | expand

Commit Message

Phil Edworthy Aug. 23, 2022, 9:32 a.m. UTC 
The WDT on RZ/V2M devices is basically the same as RZ/G2L, but without
the parity error registers. This means the driver has to reset the
hardware plus set the minimum timeout in order to do a restart and has
a single interrupt.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4:
 - Fix enum names from I2C_* to WDT_*
 - Change cast from of_device_get_match_data() to avoid clang warning
v3:
 - Don't call pm_runtime_get_sync() in restart()
 - Use mdelay instead of udelay, avoids DIV64_U64_ROUND_UP
v2:
 - Replace use of parity error registers in restart
 - Commit msg modified to reflect different contents
---
 drivers/watchdog/rzg2l_wdt.c | 39 ++++++++++++++++++++++++++++++------
 1 file changed, 33 insertions(+), 6 deletions(-)

Comments

Guenter Roeck Sept. 25, 2022, 2:41 p.m. UTC | #1 
On Tue, Aug 23, 2022 at 10:32:33AM +0100, Phil Edworthy wrote:
> The WDT on RZ/V2M devices is basically the same as RZ/G2L, but without
> the parity error registers. This means the driver has to reset the
> hardware plus set the minimum timeout in order to do a restart and has
> a single interrupt.
> 
> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

> ---
> v4:
>  - Fix enum names from I2C_* to WDT_*
>  - Change cast from of_device_get_match_data() to avoid clang warning
> v3:
>  - Don't call pm_runtime_get_sync() in restart()
>  - Use mdelay instead of udelay, avoids DIV64_U64_ROUND_UP
> v2:
>  - Replace use of parity error registers in restart
>  - Commit msg modified to reflect different contents
> ---
>  drivers/watchdog/rzg2l_wdt.c | 39 ++++++++++++++++++++++++++++++------
>  1 file changed, 33 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c
> index 6eea0ee4af49..974a4194a8fd 100644
> --- a/drivers/watchdog/rzg2l_wdt.c
> +++ b/drivers/watchdog/rzg2l_wdt.c
> @@ -10,7 +10,7 @@
>  #include <linux/io.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> -#include <linux/of.h>
> +#include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/reset.h>
> @@ -40,6 +40,11 @@ module_param(nowayout, bool, 0);
>  MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
>  				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
>  
> +enum rz_wdt_type {
> +	WDT_RZG2L,
> +	WDT_RZV2M,
> +};
> +
>  struct rzg2l_wdt_priv {
>  	void __iomem *base;
>  	struct watchdog_device wdev;
> @@ -48,6 +53,7 @@ struct rzg2l_wdt_priv {
>  	unsigned long delay;
>  	struct clk *pclk;
>  	struct clk *osc_clk;
> +	enum rz_wdt_type devtype;
>  };
>  
>  static void rzg2l_wdt_wait_delay(struct rzg2l_wdt_priv *priv)
> @@ -142,11 +148,29 @@ static int rzg2l_wdt_restart(struct watchdog_device *wdev,
>  	clk_prepare_enable(priv->pclk);
>  	clk_prepare_enable(priv->osc_clk);
>  
> -	/* Generate Reset (WDTRSTB) Signal on parity error */
> -	rzg2l_wdt_write(priv, 0, PECR);
> +	if (priv->devtype == WDT_RZG2L) {
> +		/* Generate Reset (WDTRSTB) Signal on parity error */
> +		rzg2l_wdt_write(priv, 0, PECR);
> +
> +		/* Force parity error */
> +		rzg2l_wdt_write(priv, PEEN_FORCE, PEEN);
> +	} else {
> +		/* RZ/V2M doesn't have parity error registers */
> +
> +		wdev->timeout = 0;
> +
> +		/* Initialize time out */
> +		rzg2l_wdt_init_timeout(wdev);
>  
> -	/* Force parity error */
> -	rzg2l_wdt_write(priv, PEEN_FORCE, PEEN);
> +		/* Initialize watchdog counter register */
> +		rzg2l_wdt_write(priv, 0, WDTTIM);
> +
> +		/* Enable watchdog timer*/
> +		rzg2l_wdt_write(priv, WDTCNT_WDTEN, WDTCNT);
> +
> +		/* Wait 2 consecutive overflow cycles for reset */
> +		mdelay(DIV_ROUND_UP(2 * 0xFFFFF * 1000, priv->osc_clk_rate));
> +	}
>  
>  	return 0;
>  }
> @@ -227,6 +251,8 @@ static int rzg2l_wdt_probe(struct platform_device *pdev)
>  	if (ret)
>  		return dev_err_probe(dev, ret, "failed to deassert");
>  
> +	priv->devtype = (uintptr_t)of_device_get_match_data(dev);
> +
>  	pm_runtime_enable(&pdev->dev);
>  
>  	priv->wdev.info = &rzg2l_wdt_ident;
> @@ -255,7 +281,8 @@ static int rzg2l_wdt_probe(struct platform_device *pdev)
>  }
>  
>  static const struct of_device_id rzg2l_wdt_ids[] = {
> -	{ .compatible = "renesas,rzg2l-wdt", },
> +	{ .compatible = "renesas,rzg2l-wdt", .data = (void *)WDT_RZG2L },
> +	{ .compatible = "renesas,rzv2m-wdt", .data = (void *)WDT_RZV2M },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, rzg2l_wdt_ids);
diff mbox series

Patch

diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c
index 6eea0ee4af49..974a4194a8fd 100644
--- a/drivers/watchdog/rzg2l_wdt.c
+++ b/drivers/watchdog/rzg2l_wdt.c
@@ -10,7 +10,7 @@ 
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
@@ -40,6 +40,11 @@  module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
+enum rz_wdt_type {
+	WDT_RZG2L,
+	WDT_RZV2M,
+};
+
 struct rzg2l_wdt_priv {
 	void __iomem *base;
 	struct watchdog_device wdev;
@@ -48,6 +53,7 @@  struct rzg2l_wdt_priv {
 	unsigned long delay;
 	struct clk *pclk;
 	struct clk *osc_clk;
+	enum rz_wdt_type devtype;
 };
 
 static void rzg2l_wdt_wait_delay(struct rzg2l_wdt_priv *priv)
@@ -142,11 +148,29 @@  static int rzg2l_wdt_restart(struct watchdog_device *wdev,
 	clk_prepare_enable(priv->pclk);
 	clk_prepare_enable(priv->osc_clk);
 
-	/* Generate Reset (WDTRSTB) Signal on parity error */
-	rzg2l_wdt_write(priv, 0, PECR);
+	if (priv->devtype == WDT_RZG2L) {
+		/* Generate Reset (WDTRSTB) Signal on parity error */
+		rzg2l_wdt_write(priv, 0, PECR);
+
+		/* Force parity error */
+		rzg2l_wdt_write(priv, PEEN_FORCE, PEEN);
+	} else {
+		/* RZ/V2M doesn't have parity error registers */
+
+		wdev->timeout = 0;
+
+		/* Initialize time out */
+		rzg2l_wdt_init_timeout(wdev);
 
-	/* Force parity error */
-	rzg2l_wdt_write(priv, PEEN_FORCE, PEEN);
+		/* Initialize watchdog counter register */
+		rzg2l_wdt_write(priv, 0, WDTTIM);
+
+		/* Enable watchdog timer*/
+		rzg2l_wdt_write(priv, WDTCNT_WDTEN, WDTCNT);
+
+		/* Wait 2 consecutive overflow cycles for reset */
+		mdelay(DIV_ROUND_UP(2 * 0xFFFFF * 1000, priv->osc_clk_rate));
+	}
 
 	return 0;
 }
@@ -227,6 +251,8 @@  static int rzg2l_wdt_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to deassert");
 
+	priv->devtype = (uintptr_t)of_device_get_match_data(dev);
+
 	pm_runtime_enable(&pdev->dev);
 
 	priv->wdev.info = &rzg2l_wdt_ident;
@@ -255,7 +281,8 @@  static int rzg2l_wdt_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id rzg2l_wdt_ids[] = {
-	{ .compatible = "renesas,rzg2l-wdt", },
+	{ .compatible = "renesas,rzg2l-wdt", .data = (void *)WDT_RZG2L },
+	{ .compatible = "renesas,rzv2m-wdt", .data = (void *)WDT_RZV2M },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rzg2l_wdt_ids);