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

From: Allen-KH Cheng
Date: Fri Jan 06 2023 - 06:54:56 EST


In some cases, the MediaTek watchdog requires the toprgu to reset
counter after wdt resets.

Provide a reset_by_toprgu parameter for configuration.

Signed-off-by: Allen-KH Cheng <allen-kh.cheng@xxxxxxxxxxxx>
---
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;
}

--
2.18.0