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* [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases
@ 2021-01-10 11:53 Adam Ford
  2021-01-13  6:04 ` Krzysztof Kozlowski
  2021-01-18  0:18 ` Shawn Guo
  0 siblings, 2 replies; 3+ messages in thread
From: Adam Ford @ 2021-01-10 11:53 UTC (permalink / raw)
  To: linux-arm-kernel
  Cc: aford, Adam Ford, Rob Herring, Shawn Guo, Sascha Hauer,
	Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
	devicetree, linux-kernel

On the i.MX8MN Beacon SOM, there is an RTC chip which is fed power
from the baseboard during power off.  The SNVS RTC integrated into
the SoC is not fed power.  Depending on the order the modules are
loaded, this can be a problem if the external RTC isn't rtc0.

Make the alias for rtc0 point to the external RTC all the time and
rtc1 point to the SVNS in order to correctly hold date/time over
a power-cycle.

Signed-off-by: Adam Ford <aford173@gmail.com>

diff --git a/arch/arm64/boot/dts/freescale/imx8mn-beacon-som.dtsi b/arch/arm64/boot/dts/freescale/imx8mn-beacon-som.dtsi
index 67e5e5b9ddea..2120e6485393 100644
--- a/arch/arm64/boot/dts/freescale/imx8mn-beacon-som.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mn-beacon-som.dtsi
@@ -4,6 +4,11 @@
  */
 
 / {
+	aliases {
+		rtc0 = &rtc;
+		rtc1 = &snvs_rtc;
+	};
+
 	usdhc1_pwrseq: usdhc1_pwrseq {
 		compatible = "mmc-pwrseq-simple";
 		pinctrl-names = "default";
@@ -212,7 +217,7 @@ eeprom@50 {
 		reg = <0x50>;
 	};
 
-	rtc@51 {
+	rtc: rtc@51 {
 		compatible = "nxp,pcf85263";
 		reg = <0x51>;
 	};
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases
  2021-01-10 11:53 [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases Adam Ford
@ 2021-01-13  6:04 ` Krzysztof Kozlowski
  2021-01-18  0:18 ` Shawn Guo
  1 sibling, 0 replies; 3+ messages in thread
From: Krzysztof Kozlowski @ 2021-01-13  6:04 UTC (permalink / raw)
  To: Adam Ford
  Cc: linux-arm-kernel, aford, Rob Herring, Shawn Guo, Sascha Hauer,
	Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
	devicetree, linux-kernel

On Sun, Jan 10, 2021 at 05:53:53AM -0600, Adam Ford wrote:
> On the i.MX8MN Beacon SOM, there is an RTC chip which is fed power
> from the baseboard during power off.  The SNVS RTC integrated into
> the SoC is not fed power.  Depending on the order the modules are
> loaded, this can be a problem if the external RTC isn't rtc0.
> 
> Make the alias for rtc0 point to the external RTC all the time and
> rtc1 point to the SVNS in order to correctly hold date/time over
> a power-cycle.
> 
> Signed-off-by: Adam Ford <aford173@gmail.com>

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases
  2021-01-10 11:53 [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases Adam Ford
  2021-01-13  6:04 ` Krzysztof Kozlowski
@ 2021-01-18  0:18 ` Shawn Guo
  1 sibling, 0 replies; 3+ messages in thread
From: Shawn Guo @ 2021-01-18  0:18 UTC (permalink / raw)
  To: Adam Ford
  Cc: linux-arm-kernel, aford, Rob Herring, Sascha Hauer,
	Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
	devicetree, linux-kernel

On Sun, Jan 10, 2021 at 05:53:53AM -0600, Adam Ford wrote:
> On the i.MX8MN Beacon SOM, there is an RTC chip which is fed power
> from the baseboard during power off.  The SNVS RTC integrated into
> the SoC is not fed power.  Depending on the order the modules are
> loaded, this can be a problem if the external RTC isn't rtc0.
> 
> Make the alias for rtc0 point to the external RTC all the time and
> rtc1 point to the SVNS in order to correctly hold date/time over
> a power-cycle.
> 
> Signed-off-by: Adam Ford <aford173@gmail.com>

Applied, thanks.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-01-18  0:19 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2021-01-10 11:53 [PATCH] arm64: dts: imx8mn-beacon-som: Configure RTC aliases Adam Ford
2021-01-13  6:04 ` Krzysztof Kozlowski
2021-01-18  0:18 ` Shawn Guo

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