Switch to SMC watchdog because we need direct control of HW watchdog
registers from kernel. The corresponding firmware was uploaded in
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3405.

Signed-off-by: Pin-yen Lin <treapking@chromium.org>
---

Changes in v4:
- Rename the watchdog node (smc_watchdog -> watchdog)
- Correct the patch summary (mt8173-oak -> mt8173-elm)

Changes in v3:
- Remove /delete-node/ and create a new node for SMC watchdog.

Changes in v2:
- Move the modifications to mt8173-elm.dtsi and add some comments.

 arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
index e21feb85d822..421bb2945135 100644
--- a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
@@ -161,6 +161,19 @@ hdmi_connector_in: endpoint {
 			};
 		};
 	};
+
+
+	watchdog {
+		compatible = "arm,smc-wdt";
+	};
+};
+
+/*
+ * Disable the original MMIO watch dog and switch to the SMC watchdog, which
+ * operates on the same MMIO.
+ */
+&watchdog {
+	status = "disabled";
 };
 
 &mfg_async {
-- 
2.37.1.455.g008518b4e5-goog

Il 29/07/22 05:24, Pin-yen Lin ha scritto:
> Switch to SMC watchdog because we need direct control of HW watchdog
> registers from kernel. The corresponding firmware was uploaded in
> https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3405.
> 
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> ---
> 
> Changes in v4:
> - Rename the watchdog node (smc_watchdog -> watchdog)
> - Correct the patch summary (mt8173-oak -> mt8173-elm)
> 
> Changes in v3:
> - Remove /delete-node/ and create a new node for SMC watchdog.
> 
> Changes in v2:
> - Move the modifications to mt8173-elm.dtsi and add some comments.
> 
>   arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 13 +++++++++++++
>   1 file changed, 13 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> index e21feb85d822..421bb2945135 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> @@ -161,6 +161,19 @@ hdmi_connector_in: endpoint {
>   			};
>   		};
>   	};
> +
> +

You don't need two blank lines, just one is enough (please fix).

After which:

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

> +	watchdog {
> +		compatible = "arm,smc-wdt";
> +	};
> +};
> +
> +/*
> + * Disable the original MMIO watch dog and switch to the SMC watchdog, which
> + * operates on the same MMIO.
> + */
> +&watchdog {
> +	status = "disabled";
>   };
>   
>   &mfg_async {
>

On Fri, Jul 29, 2022 at 4:01 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com> wrote:
>
> Il 29/07/22 05:24, Pin-yen Lin ha scritto:
> > Switch to SMC watchdog because we need direct control of HW watchdog
> > registers from kernel. The corresponding firmware was uploaded in
> > https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3405.
> >
> > Signed-off-by: Pin-yen Lin <treapking@chromium.org>
> > ---
> >
> > Changes in v4:
> > - Rename the watchdog node (smc_watchdog -> watchdog)
> > - Correct the patch summary (mt8173-oak -> mt8173-elm)
> >
> > Changes in v3:
> > - Remove /delete-node/ and create a new node for SMC watchdog.
> >
> > Changes in v2:
> > - Move the modifications to mt8173-elm.dtsi and add some comments.
> >
> >   arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 13 +++++++++++++
> >   1 file changed, 13 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> > index e21feb85d822..421bb2945135 100644
> > --- a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> > +++ b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
> > @@ -161,6 +161,19 @@ hdmi_connector_in: endpoint {
> >                       };
> >               };
> >       };
> > +
> > +
>
> You don't need two blank lines, just one is enough (please fix).

This is already addressed in v5. Thanks for the review though.
>
> After which:
>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>
> > +     watchdog {
> > +             compatible = "arm,smc-wdt";
> > +     };
> > +};
> > +
> > +/*
> > + * Disable the original MMIO watch dog and switch to the SMC watchdog, which
> > + * operates on the same MMIO.
> > + */
> > +&watchdog {
> > +     status = "disabled";
> >   };
> >
> >   &mfg_async {
> >
>
>