[PATCH 0/2] arm64: dts: qcom: x1e80100: Enable APSS watchdog in EL2

[PATCH 0/2] arm64: dts: qcom: x1e80100: Enable APSS watchdog in EL2

[Abel Vesa]

On X1E80100 platforms, in EL2, the APSS watchdog is accessible.
The APSS WDT HW is compatible with the one from SC8280XP, SM8250 and the
like. So describe it in the EL2 overlay and document its compatible.

Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
---
Abel Vesa (2):
      dt-bindings: watchdog: Document X1E80100 compatible
      arm64: dts: qcom: x1-el2: Add the APSS watchdog

 Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml |  1 +
 arch/arm64/boot/dts/qcom/x1-el2.dtso                     | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)
---
base-commit: d9771d0dbe18dd643760431870a6abf9b0866bb0
change-id: 20251214-arm64-dts-qcom-x1e80100-el2-add-apss-wdt-e04ca6c99f0f

Best regards,
--  
Abel Vesa <abel.vesa@oss.qualcomm.com>

[PATCH 1/2] dt-bindings: watchdog: Document X1E80100 compatible

[Abel Vesa]

Document the compatible for the X1E80100 platform to the Qualcomm watchdog
binding. The HW implementation is compatible with the KPSS WDT.

Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml b/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
index 54f5311ed016..f2c4bc900e5f 100644
--- a/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
+++ b/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
@@ -43,6 +43,7 @@ properties:
               - qcom,apss-wdt-sm6350
               - qcom,apss-wdt-sm8150
               - qcom,apss-wdt-sm8250
+              - qcom,apss-wdt-x1e80100
           - const: qcom,kpss-wdt
       - const: qcom,kpss-wdt
         deprecated: true

-- 
2.48.1

Re: [PATCH 1/2] dt-bindings: watchdog: Document X1E80100 compatible

[Rob Herring (Arm)]

On Sun, 14 Dec 2025 22:49:58 +0200, Abel Vesa wrote:
> Document the compatible for the X1E80100 platform to the Qualcomm watchdog
> binding. The HW implementation is compatible with the KPSS WDT.
> 
> Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
> ---
>  Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml | 1 +
>  1 file changed, 1 insertion(+)
> 

Acked-by: Rob Herring (Arm) <robh@kernel.org>

[PATCH 2/2] arm64: dts: qcom: x1-el2: Add the APSS watchdog

[Abel Vesa]

The watchdog support in EL1 is SBSA compliant, handled by Gunyah
hypervisor, but in EL2. the watchdog is an instance of the APSS WDT HW
block, same as older platforms. So describe the APSS WDT node in the EL2
overlay.

Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/x1-el2.dtso | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/x1-el2.dtso b/arch/arm64/boot/dts/qcom/x1-el2.dtso
index 2d1c9151cf1b..404174a15659 100644
--- a/arch/arm64/boot/dts/qcom/x1-el2.dtso
+++ b/arch/arm64/boot/dts/qcom/x1-el2.dtso
@@ -7,6 +7,8 @@
 /dts-v1/;
 /plugin/;
 
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
 /* We can't and don't need to use zap shader in EL2 as linux can zap the gpu on it's own. */
 &gpu_zap_shader {
 	status = "disabled";
@@ -55,3 +57,17 @@ &pcie_smmu {
 &sbsa_watchdog {
 	status = "disabled";
 };
+
+&soc {
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	/* The APSS watchdog is only accessible in EL2 */
+	watchdog@17410000 {
+		compatible = "qcom,apss-wdt-x1e80100", "qcom,kpss-wdt";
+		reg = <0x0 0x17410000 0x0 0x1000>;
+		clocks = <&sleep_clk>;
+		interrupts = <GIC_SPI 0 IRQ_TYPE_EDGE_RISING>;
+		interrupt-parent = <&intc>;
+	};
+};

-- 
2.48.1

Re: [PATCH 2/2] arm64: dts: qcom: x1-el2: Add the APSS watchdog

[Dmitry Baryshkov]

On Sun, Dec 14, 2025 at 10:49:59PM +0200, Abel Vesa wrote:
> The watchdog support in EL1 is SBSA compliant, handled by Gunyah
> hypervisor, but in EL2. the watchdog is an instance of the APSS WDT HW
> block, same as older platforms. So describe the APSS WDT node in the EL2
> overlay.
> 
> Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/x1-el2.dtso | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>


-- 
With best wishes
Dmitry

Re: [PATCH 2/2] arm64: dts: qcom: x1-el2: Add the APSS watchdog

[Stephan Gerhold]

On Sun, Dec 14, 2025 at 10:49:59PM +0200, Abel Vesa wrote:
> The watchdog support in EL1 is SBSA compliant, handled by Gunyah
> hypervisor, but in EL2. the watchdog is an instance of the APSS WDT HW
> block, same as older platforms. So describe the APSS WDT node in the EL2
> overlay.
> 
> Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/x1-el2.dtso | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/x1-el2.dtso b/arch/arm64/boot/dts/qcom/x1-el2.dtso
> index 2d1c9151cf1b..404174a15659 100644
> --- a/arch/arm64/boot/dts/qcom/x1-el2.dtso
> +++ b/arch/arm64/boot/dts/qcom/x1-el2.dtso
> @@ -7,6 +7,8 @@
>  /dts-v1/;
>  /plugin/;
>  
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +
>  /* We can't and don't need to use zap shader in EL2 as linux can zap the gpu on it's own. */
>  &gpu_zap_shader {
>  	status = "disabled";
> @@ -55,3 +57,17 @@ &pcie_smmu {
>  &sbsa_watchdog {
>  	status = "disabled";
>  };
> +
> +&soc {
> +	#address-cells = <2>;
> +	#size-cells = <2>;
> +
> +	/* The APSS watchdog is only accessible in EL2 */
> +	watchdog@17410000 {
> +		compatible = "qcom,apss-wdt-x1e80100", "qcom,kpss-wdt";
> +		reg = <0x0 0x17410000 0x0 0x1000>;
> +		clocks = <&sleep_clk>;
> +		interrupts = <GIC_SPI 0 IRQ_TYPE_EDGE_RISING>;
> +		interrupt-parent = <&intc>;
> +	};

For consistency with &pcie_smmu, I think it would be cleaner to put this
into hamoa.dtsi, mark it as status = "reserved"; and then enable it here
in the overlay. That way, we have a full hardware description in
hamoa.dtsi.

You should also be able to drop the interrupt-parent if you move it
there.

Thanks,
Stephan

Re: [PATCH 2/2] arm64: dts: qcom: x1-el2: Add the APSS watchdog

[Abel Vesa]

On 25-12-18 11:06:08, Stephan Gerhold wrote:
> On Sun, Dec 14, 2025 at 10:49:59PM +0200, Abel Vesa wrote:
> > The watchdog support in EL1 is SBSA compliant, handled by Gunyah
> > hypervisor, but in EL2. the watchdog is an instance of the APSS WDT HW
> > block, same as older platforms. So describe the APSS WDT node in the EL2
> > overlay.
> > 
> > Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
> > ---
> >  arch/arm64/boot/dts/qcom/x1-el2.dtso | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/qcom/x1-el2.dtso b/arch/arm64/boot/dts/qcom/x1-el2.dtso
> > index 2d1c9151cf1b..404174a15659 100644
> > --- a/arch/arm64/boot/dts/qcom/x1-el2.dtso
> > +++ b/arch/arm64/boot/dts/qcom/x1-el2.dtso
> > @@ -7,6 +7,8 @@
> >  /dts-v1/;
> >  /plugin/;
> >  
> > +#include <dt-bindings/interrupt-controller/arm-gic.h>
> > +
> >  /* We can't and don't need to use zap shader in EL2 as linux can zap the gpu on it's own. */
> >  &gpu_zap_shader {
> >  	status = "disabled";
> > @@ -55,3 +57,17 @@ &pcie_smmu {
> >  &sbsa_watchdog {
> >  	status = "disabled";
> >  };
> > +
> > +&soc {
> > +	#address-cells = <2>;
> > +	#size-cells = <2>;
> > +
> > +	/* The APSS watchdog is only accessible in EL2 */
> > +	watchdog@17410000 {
> > +		compatible = "qcom,apss-wdt-x1e80100", "qcom,kpss-wdt";
> > +		reg = <0x0 0x17410000 0x0 0x1000>;
> > +		clocks = <&sleep_clk>;
> > +		interrupts = <GIC_SPI 0 IRQ_TYPE_EDGE_RISING>;
> > +		interrupt-parent = <&intc>;
> > +	};
> 
> For consistency with &pcie_smmu, I think it would be cleaner to put this
> into hamoa.dtsi, mark it as status = "reserved"; and then enable it here
> in the overlay. That way, we have a full hardware description in
> hamoa.dtsi.

Sounds like a good idea. Will do that in v2.

> 
> You should also be able to drop the interrupt-parent if you move it
> there.

Yes. It will not be needed.

Thanks for reviewing,
Abel