[PATCH 2/2] watchdog: s3c2410_wdt: Add support for Exynos8855 SoC

From: Alim Akhtar

Date: Sun Sep 27 2026 - 10:13:49 EST


Watchdog IP on this SoC is similar to Exynos850/ExynosAutov{9/920}.
This does not have CNT_EN_WDT bit in PMU and offset of RST_STAT is
different then the previously support SoC.
Reuse the offset as much as from already supported SoC

Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
---
drivers/watchdog/s3c2410_wdt.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 7053963fb0ac..8ce4ca3e2aa8 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -58,6 +58,7 @@
#define S3C2410_WATCHDOG_DEFAULT_TIME (15)

#define EXYNOS5_RST_STAT_REG_OFFSET 0x0404
+#define EXYNOS8855_RST_STAT_REG_OFFSET 0x10
#define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
#define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
#define EXYNOS850_CLUSTER0_NONCPU_OUT 0x1220
@@ -281,6 +282,26 @@ static const struct s3c2410_wdt_variant drv_data_exynos850_cl1 = {
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_CNT_EN,
};

+static const struct s3c2410_wdt_variant drv_data_exynos8855_cl0 = {
+ .mask_reset_reg = EXYNOS850_CLUSTER0_NONCPU_INT_EN,
+ .mask_bit = 2,
+ .mask_reset_inv = true,
+ .rst_stat_reg = EXYNOS8855_RST_STAT_REG_OFFSET,
+ .rst_stat_bit = EXYNOS850_CLUSTER0_WDTRESET_BIT,
+ .quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET |
+ QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_DBGACK_BIT,
+};
+
+static const struct s3c2410_wdt_variant drv_data_exynos8855_cl1 = {
+ .mask_reset_reg = EXYNOSAUTOV920_CLUSTER1_NONCPU_INT_EN,
+ .mask_bit = 2,
+ .mask_reset_inv = true,
+ .rst_stat_reg = EXYNOS8855_RST_STAT_REG_OFFSET,
+ .rst_stat_bit = EXYNOSAUTOV9_CLUSTER0_WDTRESET_BIT,
+ .quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET |
+ QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_DBGACK_BIT,
+};
+
static const struct s3c2410_wdt_variant drv_data_exynos990_cl0 = {
.mask_reset_reg = GS_CLUSTER0_NONCPU_INT_EN,
.mask_bit = 2,
@@ -400,6 +421,8 @@ static const struct of_device_id s3c2410_wdt_match[] = {
.data = &drv_data_exynos7 },
{ .compatible = "samsung,exynos850-wdt",
.data = &drv_data_exynos850_cl0 },
+ { .compatible = "samsung,exynos8855-wdt",
+ .data = &drv_data_exynos8855_cl0 },
{ .compatible = "samsung,exynos990-wdt",
.data = &drv_data_exynos990_cl0 },
{ .compatible = "samsung,exynosautov9-wdt",
@@ -723,6 +746,7 @@ s3c2410_get_wdt_drv_data(struct platform_device *pdev, struct s3c2410_wdt *wdt)
/* Choose Exynos850/ExynosAutov9 driver data w.r.t. cluster index */
if (variant == &drv_data_exynos850_cl0 ||
variant == &drv_data_exynosautov9_cl0 ||
+ variant == &drv_data_exynos8855_cl0 ||
variant == &drv_data_gs101_cl0 ||
variant == &drv_data_exynosautov920_cl0 ||
variant == &drv_data_exynos990_cl0) {
@@ -740,6 +764,8 @@ s3c2410_get_wdt_drv_data(struct platform_device *pdev, struct s3c2410_wdt *wdt)
case 1:
if (variant == &drv_data_exynos850_cl0)
variant = &drv_data_exynos850_cl1;
+ else if (variant == &drv_data_exynos8855_cl0)
+ variant = &drv_data_exynos8855_cl1;
else if (variant == &drv_data_exynosautov9_cl0)
variant = &drv_data_exynosautov9_cl1;
else if (variant == &drv_data_gs101_cl0)
--
2.34.1