[PATCH] ARM: dts: imx6qdl-hummingboard: Add rtc0 and rtc1 aliases to fix hctosys

Josua Mayer josua at solid-run.com
Thu Jan 18 07:01:10 PST 2024


HummingBoard has two RTCs, first integrated within SoC that can be used to
wake up from sleep - and a second on the carrier board including back-up
battery which is intended for keeping time during power-off.

Add aliases for both, ensuring that the battery-backed clock is primary
rtc and used by default during boot for restoring system time.

Fixes keeping time across power-cycle observed on Debian,
which sets RTC_HCTOSYS_DEVICE="rtc0".

Signed-off-by: Josua Mayer <josua at solid-run.com>
---
 arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard.dtsi  | 7 ++++++-
 arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard2.dtsi | 5 +++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard.dtsi b/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard.dtsi
index bfade7149080..a955c77cd499 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard.dtsi
@@ -41,6 +41,11 @@
 #include <dt-bindings/sound/fsl-imx-audmux.h>
 
 / {
+	aliases {
+		rtc0 = &carrier_rtc;
+		rtc1 = &snvs_rtc;
+	};
+
 	/* Will be filled by the bootloader */
 	memory at 10000000 {
 		device_type = "memory";
@@ -187,7 +192,7 @@ &i2c1 {
 	status = "okay";
 
 	/* Pro baseboard model */
-	rtc at 68 {
+	carrier_rtc: rtc at 68 {
 		compatible = "nxp,pcf8523";
 		reg = <0x68>;
 	};
diff --git a/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard2.dtsi b/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard2.dtsi
index 0883ef99cded..e6017f9bf640 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard2.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/imx6qdl-hummingboard2.dtsi
@@ -41,6 +41,11 @@
 #include <dt-bindings/sound/fsl-imx-audmux.h>
 
 / {
+	aliases {
+		rtc0 = &pcf8523;
+		rtc1 = &snvs_rtc;
+	};
+
 	/* Will be filled by the bootloader */
 	memory at 10000000 {
 		device_type = "memory";

---
base-commit: 0dd3ee31125508cd67f7e7172247f05b7fd1753a
change-id: 20240118-imx6-hb-primary-rtc-047d47fd6eaa

Sincerely,
-- 
Josua Mayer <josua at solid-run.com>




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