[PATCH v2] arm64: dts: mt8173-oak: Switch to SMC watchdog

[Pin-yen Lin]

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 at chromium.org>
---

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

 arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
index e21feb85d822..b2269770abc3 100644
--- a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi
@@ -161,6 +161,18 @@ hdmi_connector_in: endpoint {
 			};
 		};
 	};
+
+	soc {
+		/*
+		 * Disable the original MMIO watch dog and switch to the SMC watchdog,
+		 * which operates on the same MMIO.
+		 */
+		/delete-node/ watchdog at 10007000;
+
+		watchdog {
+			compatible = "arm,smc-wdt";
+		};
+	};
 };
 
 &mfg_async {
-- 
2.37.1.359.gd136c6c3e2-goog