[PATCH v4 7/8] watchdog: ulp_wdog: Use driver model for reset_cpu()
alice.guo at oss.nxp.com
alice.guo at oss.nxp.com
Tue May 19 08:22:07 CEST 2026
From: Alice Guo <alice.guo at nxp.com>
Replace hardcoded WDOG_BASE_ADDR with driver model based dynamic address
lookup from device tree, allowing reset_cpu() to dynamically locate
watchdog devices from device tree.
This change also enables CONFIG_WDT for relevant boards and ensures the
watchdog nodes are available for driver model usage.
- Remove hardcoded WDOG_BASE_ADDR from hw_watchdog_* functions
- Reimplement reset_cpu() using UCLASS_WDT device iteration
- Add ulp_wdt_expire_now() callback for standard WDT interface
- Pass wdog register pointer to hw_watchdog_set_timeout()
- Enable CONFIG_WDT for boards using ULP watchdog
- Remove wdog3 status = "disabled" overrides from U-Boot device tree
overlays, as the watchdog device needs to be accessible for driver
model based reset functionality.
Signed-off-by: Alice Guo <alice.guo at nxp.com>
Acked-by: Francesco Dolcini <francesco.dolcini at toradex.com> # Toradex boards
---
arch/arm/dts/imx8ulp-evk-u-boot.dtsi | 4 --
arch/arm/dts/imx943-evk-u-boot.dtsi | 4 --
arch/arm/dts/imx95-15x15-evk-u-boot.dtsi | 4 --
arch/arm/dts/imx95-19x19-evk-u-boot.dtsi | 4 --
arch/arm/dts/imx95-toradex-smarc-dev-u-boot.dtsi | 4 --
arch/arm/dts/imx95-verdin-wifi-dev-u-boot.dtsi | 4 --
configs/imx8ulp_evk_defconfig | 1 +
configs/imx93-phycore_defconfig | 1 +
configs/imx943_evk_defconfig | 1 +
configs/imx95_15x15_evk_defconfig | 1 +
configs/imx95_evk.config | 1 +
configs/mx7ulp_com_defconfig | 1 +
configs/toradex-smarc-imx95_defconfig | 1 +
configs/verdin-imx95_defconfig | 1 +
drivers/watchdog/ulp_wdog.c | 79 +++++++++---------------
15 files changed, 36 insertions(+), 75 deletions(-)
diff --git a/arch/arm/dts/imx8ulp-evk-u-boot.dtsi b/arch/arm/dts/imx8ulp-evk-u-boot.dtsi
index 860994129ae..ac130b54738 100644
--- a/arch/arm/dts/imx8ulp-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx8ulp-evk-u-boot.dtsi
@@ -26,10 +26,6 @@
status = "disabled";
};
-&wdog3 {
- status = "disabled";
-};
-
&per_bridge4 {
bootph-pre-ram;
};
diff --git a/arch/arm/dts/imx943-evk-u-boot.dtsi b/arch/arm/dts/imx943-evk-u-boot.dtsi
index 247a7ed6838..3b3619d2232 100644
--- a/arch/arm/dts/imx943-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx943-evk-u-boot.dtsi
@@ -153,10 +153,6 @@
bootph-pre-ram;
};
-&wdog3 {
- status = "disabled";
-};
-
&xspi1 {
bootph-pre-ram;
pinctrl-names = "default";
diff --git a/arch/arm/dts/imx95-15x15-evk-u-boot.dtsi b/arch/arm/dts/imx95-15x15-evk-u-boot.dtsi
index 514dd729be9..34b4073ff35 100644
--- a/arch/arm/dts/imx95-15x15-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx95-15x15-evk-u-boot.dtsi
@@ -44,10 +44,6 @@
bootph-pre-ram;
};
-&wdog3 {
- status = "disabled";
-};
-
&pinctrl_uart1 {
bootph-pre-ram;
};
diff --git a/arch/arm/dts/imx95-19x19-evk-u-boot.dtsi b/arch/arm/dts/imx95-19x19-evk-u-boot.dtsi
index 8b59831b7ca..1083d863c4d 100644
--- a/arch/arm/dts/imx95-19x19-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx95-19x19-evk-u-boot.dtsi
@@ -28,10 +28,6 @@
bootph-pre-ram;
};
-&wdog3 {
- status = "disabled";
-};
-
&pinctrl_uart1 {
bootph-pre-ram;
};
diff --git a/arch/arm/dts/imx95-toradex-smarc-dev-u-boot.dtsi b/arch/arm/dts/imx95-toradex-smarc-dev-u-boot.dtsi
index 97ce7402e50..c30e2d6aaee 100644
--- a/arch/arm/dts/imx95-toradex-smarc-dev-u-boot.dtsi
+++ b/arch/arm/dts/imx95-toradex-smarc-dev-u-boot.dtsi
@@ -104,7 +104,3 @@
&usdhc2 {
bootph-pre-ram;
};
-
-&wdog3 {
- status = "disabled";
-};
diff --git a/arch/arm/dts/imx95-verdin-wifi-dev-u-boot.dtsi b/arch/arm/dts/imx95-verdin-wifi-dev-u-boot.dtsi
index 83802156d52..7d16001baa5 100644
--- a/arch/arm/dts/imx95-verdin-wifi-dev-u-boot.dtsi
+++ b/arch/arm/dts/imx95-verdin-wifi-dev-u-boot.dtsi
@@ -106,7 +106,3 @@
&usdhc1 {
bootph-pre-ram;
};
-
-&wdog3 {
- status = "disabled";
-};
diff --git a/configs/imx8ulp_evk_defconfig b/configs/imx8ulp_evk_defconfig
index baa8c1e4695..2101532833e 100644
--- a/configs/imx8ulp_evk_defconfig
+++ b/configs/imx8ulp_evk_defconfig
@@ -92,3 +92,4 @@ CONFIG_SPI=y
CONFIG_DM_SPI=y
CONFIG_NXP_FSPI=y
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
diff --git a/configs/imx93-phycore_defconfig b/configs/imx93-phycore_defconfig
index 0634378149d..f87581d4ddc 100644
--- a/configs/imx93-phycore_defconfig
+++ b/configs/imx93-phycore_defconfig
@@ -156,6 +156,7 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x1fc9
CONFIG_USB_GADGET_PRODUCT_NUM=0x0152
CONFIG_CI_UDC=y
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
# CONFIG_RSA is not set
# CONFIG_SPL_SHA256 is not set
CONFIG_LZO=y
diff --git a/configs/imx943_evk_defconfig b/configs/imx943_evk_defconfig
index 70265f13bba..b60d39a1fa2 100644
--- a/configs/imx943_evk_defconfig
+++ b/configs/imx943_evk_defconfig
@@ -151,3 +151,4 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5
CONFIG_SDP_LOADADDR=0x90400000
CONFIG_SPL_USB_SDP_SUPPORT=y
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
diff --git a/configs/imx95_15x15_evk_defconfig b/configs/imx95_15x15_evk_defconfig
index e9cd289d31f..3c18956ffe9 100644
--- a/configs/imx95_15x15_evk_defconfig
+++ b/configs/imx95_15x15_evk_defconfig
@@ -147,5 +147,6 @@ CONFIG_SPI=y
CONFIG_DM_SPI=y
CONFIG_NXP_FSPI=y
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
CONFIG_LZO=y
CONFIG_BZIP2=y
diff --git a/configs/imx95_evk.config b/configs/imx95_evk.config
index 30ad2e60313..743778d9554 100644
--- a/configs/imx95_evk.config
+++ b/configs/imx95_evk.config
@@ -151,3 +151,4 @@ CONFIG_NXP_FSPI=y
CONFIG_ULP_WATCHDOG=y
CONFIG_LZO=y
CONFIG_BZIP2=y
+CONFIG_WDT=y
diff --git a/configs/mx7ulp_com_defconfig b/configs/mx7ulp_com_defconfig
index d63168fe886..c9c3f6b5f26 100644
--- a/configs/mx7ulp_com_defconfig
+++ b/configs/mx7ulp_com_defconfig
@@ -63,3 +63,4 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5
CONFIG_CI_UDC=y
CONFIG_USB_GADGET_DOWNLOAD=y
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
diff --git a/configs/toradex-smarc-imx95_defconfig b/configs/toradex-smarc-imx95_defconfig
index caf0718fc13..9363eb5cbb6 100644
--- a/configs/toradex-smarc-imx95_defconfig
+++ b/configs/toradex-smarc-imx95_defconfig
@@ -175,5 +175,6 @@ CONFIG_USB_GADGET_OS_DESCRIPTORS=y
CONFIG_CI_UDC=y
CONFIG_SDP_LOADADDR=0x90400000
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
# CONFIG_SPL_SHA1 is not set
CONFIG_LZO=y
diff --git a/configs/verdin-imx95_defconfig b/configs/verdin-imx95_defconfig
index 50515250d17..ea1ebb0c492 100644
--- a/configs/verdin-imx95_defconfig
+++ b/configs/verdin-imx95_defconfig
@@ -180,5 +180,6 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0x4000
CONFIG_USB_GADGET_OS_DESCRIPTORS=y
CONFIG_SDP_LOADADDR=0x90400000
CONFIG_ULP_WATCHDOG=y
+CONFIG_WDT=y
# CONFIG_SPL_SHA1 is not set
CONFIG_LZO=y
diff --git a/drivers/watchdog/ulp_wdog.c b/drivers/watchdog/ulp_wdog.c
index 83f19dc0e86..e3a89031c44 100644
--- a/drivers/watchdog/ulp_wdog.c
+++ b/drivers/watchdog/ulp_wdog.c
@@ -7,6 +7,7 @@
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
#include <dm.h>
+#include <linux/delay.h>
#include <wdt.h>
/*
@@ -51,11 +52,9 @@ struct ulp_wdt_priv {
#define CLK_RATE_1KHZ 1000
#define CLK_RATE_32KHZ 125
-void hw_watchdog_set_timeout(u16 val)
+void hw_watchdog_set_timeout(struct wdog_regs *wdog, u16 val)
{
/* setting timeout value */
- struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
-
writel(val, &wdog->toval);
}
@@ -89,7 +88,7 @@ void ulp_watchdog_init(struct wdog_regs *wdog, u16 timeout)
while (!(readl(&wdog->cs) & WDGCS_ULK))
;
- hw_watchdog_set_timeout(timeout);
+ hw_watchdog_set_timeout(wdog, timeout);
writel(0, &wdog->win);
/* setting 1-kHz clock source, enable counter running, and clear interrupt */
@@ -107,57 +106,20 @@ void ulp_watchdog_init(struct wdog_regs *wdog, u16 timeout)
ulp_watchdog_reset(wdog);
}
-void hw_watchdog_reset(void)
-{
- struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
-
- ulp_watchdog_reset(wdog);
-}
-
-void hw_watchdog_init(void)
-{
- struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
-
- ulp_watchdog_init(wdog, CONFIG_WATCHDOG_TIMEOUT_MSECS);
-}
-
-#if !CONFIG_IS_ENABLED(SYSRESET)
+#if !CONFIG_IS_ENABLED(SYSRESET) && CONFIG_IS_ENABLED(WDT)
void reset_cpu(void)
{
- struct wdog_regs *wdog = (struct wdog_regs *)WDOG_BASE_ADDR;
- u32 cmd32 = 0;
-
- if (readl(&wdog->cs) & WDGCS_CMD32EN) {
- writel(UNLOCK_WORD, &wdog->cnt);
- cmd32 = WDGCS_CMD32EN;
- } else {
- dmb();
- __raw_writel(UNLOCK_WORD0, &wdog->cnt);
- __raw_writel(UNLOCK_WORD1, &wdog->cnt);
- dmb();
- }
+ struct udevice *wdt;
- /* Wait WDOG Unlock */
- while (!(readl(&wdog->cs) & WDGCS_ULK))
- ;
+ for (uclass_first_device(UCLASS_WDT, &wdt);
+ wdt;
+ uclass_next_device(&wdt)) {
+ if (!dev_read_enabled(wdt))
+ continue;
- hw_watchdog_set_timeout(5); /* 5ms timeout for general; 40ms timeout for imx93 */
- writel(0, &wdog->win);
-
- /* enable counter running */
- if (IS_ENABLED(CONFIG_ARCH_IMX9))
- writel((cmd32 | WDGCS_WDGE | (WDG_LPO_CLK << 8) | WDOG_CS_PRES |
- WDGCS_INT), &wdog->cs);
- else
- writel((cmd32 | WDGCS_WDGE | (WDG_LPO_CLK << 8)), &wdog->cs);
-
- /* Wait WDOG reconfiguration */
- while (!(readl(&wdog->cs) & WDGCS_RCS))
- ;
-
- hw_watchdog_reset();
-
- while (1);
+ wdt_expire_now(wdt, 0);
+ break;
+ }
}
#endif
@@ -184,6 +146,20 @@ static int ulp_wdt_reset(struct udevice *dev)
return 0;
}
+static int ulp_wdt_expire_now(struct udevice *dev, ulong flags)
+{
+ int ret;
+
+ /* 5ms timeout for all others; 40ms timeout for "fsl,imx93-wdt" */
+ ret = ulp_wdt_start(dev, 5, flags);
+ if (ret)
+ return ret;
+
+ mdelay(50);
+
+ return 0;
+}
+
static int ulp_wdt_probe(struct udevice *dev)
{
struct ulp_wdt_priv *priv = dev_get_priv(dev);
@@ -202,6 +178,7 @@ static int ulp_wdt_probe(struct udevice *dev)
static const struct wdt_ops ulp_wdt_ops = {
.start = ulp_wdt_start,
.reset = ulp_wdt_reset,
+ .expire_now = ulp_wdt_expire_now,
};
static const struct udevice_id ulp_wdt_ids[] = {
--
2.34.1
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