[PATCH 5.10.y-cip 08/23] watchdog: rzg2l_wdt: Add rzv2m support

Biju Das
2023-05-19T08:21:27Z

From: Phil Edworthy <phil.edworthy@renesas.com>

commit ec122fd94eeb87b2e906360efe7447362f83e9ae upstream.

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>
Link: https://lore.kernel.org/r/20220823093233.8577-3-phil.edworthy@renesas.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
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 d217bc54b729..ceca42db0837 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)
@@ -140,11 +146,29 @@ 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;
}
@@ -225,6 +249,8 @@ 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;
@@ -253,7 +279,8 @@ 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);
--
2.25.1