[PATCH 1/3] arm64: dts: allwinner: a527: cubie-a5e: Drop external 32.768 KHz crystal

[PATCH 1/3] arm64: dts: allwinner: a527: cubie-a5e: Drop external 32.768 KHz crystal

[Chen-Yu Tsai]

From: Chen-Yu Tsai <wens@csie.org>

The Radxa Cubie A5E has empty pads for a 32.768 KHz crystal, but it is
left unpopulated, as per the schematics and seen on board images. A dead
give away is the RTC's LOSC auto switch register showing the external
OSC to be abnormal.

Drop the external crystal from the device tree. It was not referenced
anyway.

Fixes: c2520cd032ae ("arm64: dts: allwinner: a523: add Radxa A5E support")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts b/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
index 71074b072184..e333bbaf01d3 100644
--- a/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
+++ b/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
@@ -24,13 +24,6 @@ chosen {
 		stdout-path = "serial0:115200n8";
 	};
 
-	ext_osc32k: ext-osc32k-clk {
-		#clock-cells = <0>;
-		compatible = "fixed-clock";
-		clock-frequency = <32768>;
-		clock-output-names = "ext_osc32k";
-	};
-
 	leds {
 		compatible = "gpio-leds";
 
-- 
2.39.5

[PATCH 2/3] arm64: dts: allwinner: t527: avaota-a1: hook up external 32k crystal

[Chen-Yu Tsai]

From: Chen-Yu Tsai <wens@csie.org>

When the board was added, its external 32.768 KHz crystal was described
but not hooked up correctly. This meant the device had to fall back to
the SoC's internal oscillator or divide a 32 KHz clock from the main
oscillator, neither of which are accurate for the RTC. As a result the
RTC clock will drift badly.

Hook the crystal up to the RTC block and request the correct clock rate.

Fixes: dbe54efa32af ("arm64: dts: allwinner: a523: add Avaota-A1 router support")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts b/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
index 535387912d9b..054d0357c139 100644
--- a/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
+++ b/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
@@ -354,6 +354,14 @@ &r_pio {
 	vcc-pm-supply = <&reg_aldo3>;
 };
 
+&rtc {
+	clocks = <&r_ccu CLK_BUS_R_RTC>, <&osc24M>,
+		 <&r_ccu CLK_R_AHB>, <&ext_osc32k>;
+	clock-names = "bus", "hosc", "ahb", "ext-osc32k";
+	assigned-clocks = <&rtc CLK_OSC32K>;
+	assigned-clock-rates = <32768>;
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pb_pins>;
-- 
2.39.5

Re: [PATCH 2/3] arm64: dts: allwinner: t527: avaota-a1: hook up external 32k crystal

[Jernej Škrabec]

Dne sobota, 13. september 2025 ob 12:24:49 Srednjeevropski poletni čas je Chen-Yu Tsai napisal(a):
> From: Chen-Yu Tsai <wens@csie.org>
> 
> When the board was added, its external 32.768 KHz crystal was described
> but not hooked up correctly. This meant the device had to fall back to
> the SoC's internal oscillator or divide a 32 KHz clock from the main
> oscillator, neither of which are accurate for the RTC. As a result the
> RTC clock will drift badly.
> 
> Hook the crystal up to the RTC block and request the correct clock rate.
> 
> Fixes: dbe54efa32af ("arm64: dts: allwinner: a523: add Avaota-A1 router support")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> ---
>  arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts b/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
> index 535387912d9b..054d0357c139 100644
> --- a/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts
> @@ -354,6 +354,14 @@ &r_pio {
>  	vcc-pm-supply = <&reg_aldo3>;
>  };
>  
> +&rtc {
> +	clocks = <&r_ccu CLK_BUS_R_RTC>, <&osc24M>,
> +		 <&r_ccu CLK_R_AHB>, <&ext_osc32k>;
> +	clock-names = "bus", "hosc", "ahb", "ext-osc32k";
> +	assigned-clocks = <&rtc CLK_OSC32K>;
> +	assigned-clock-rates = <32768>;
> +};
> +
>  &uart0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&uart0_pb_pins>;
> 

[PATCH 3/3] arm64: dts: allwinner: t527: orangepi-4a: hook up external 32k crystal

[Chen-Yu Tsai]

From: Chen-Yu Tsai <wens@csie.org>

When the board was added, its external 32.768 KHz crystal was described
but not hooked up correctly. This meant the device had to fall back to
the SoC's internal oscillator or divide a 32 KHz clock from the main
oscillator, neither of which are accurate for the RTC. As a result the
RTC clock will drift badly.

Hook the crystal up to the RTC block and request the correct clock rate.

Fixes: de713ccb9934 ("arm64: dts: allwinner: t527: Add OrangePi 4A board")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts b/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
index fb5311a46c2e..f71860db83d3 100644
--- a/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
+++ b/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
@@ -393,6 +393,14 @@ &r_pio {
 	vcc-pm-supply = <&reg_bldo2>;
 };
 
+&rtc {
+	clocks = <&r_ccu CLK_BUS_R_RTC>, <&osc24M>,
+		 <&r_ccu CLK_R_AHB>, <&ext_osc32k>;
+	clock-names = "bus", "hosc", "ahb", "ext-osc32k";
+	assigned-clocks = <&rtc CLK_OSC32K>;
+	assigned-clock-rates = <32768>;
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pb_pins>;
-- 
2.39.5

Re: [PATCH 3/3] arm64: dts: allwinner: t527: orangepi-4a: hook up external 32k crystal

[Jernej Škrabec]

Dne sobota, 13. september 2025 ob 12:24:50 Srednjeevropski poletni čas je Chen-Yu Tsai napisal(a):
> From: Chen-Yu Tsai <wens@csie.org>
> 
> When the board was added, its external 32.768 KHz crystal was described
> but not hooked up correctly. This meant the device had to fall back to
> the SoC's internal oscillator or divide a 32 KHz clock from the main
> oscillator, neither of which are accurate for the RTC. As a result the
> RTC clock will drift badly.
> 
> Hook the crystal up to the RTC block and request the correct clock rate.
> 
> Fixes: de713ccb9934 ("arm64: dts: allwinner: t527: Add OrangePi 4A board")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> ---
>  arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts b/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
> index fb5311a46c2e..f71860db83d3 100644
> --- a/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts
> @@ -393,6 +393,14 @@ &r_pio {
>  	vcc-pm-supply = <&reg_bldo2>;
>  };
>  
> +&rtc {
> +	clocks = <&r_ccu CLK_BUS_R_RTC>, <&osc24M>,
> +		 <&r_ccu CLK_R_AHB>, <&ext_osc32k>;
> +	clock-names = "bus", "hosc", "ahb", "ext-osc32k";
> +	assigned-clocks = <&rtc CLK_OSC32K>;
> +	assigned-clock-rates = <32768>;
> +};
> +
>  &uart0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&uart0_pb_pins>;
> 

Re: [PATCH 1/3] arm64: dts: allwinner: a527: cubie-a5e: Drop external 32.768 KHz crystal

[Jernej Škrabec]

Dne sobota, 13. september 2025 ob 12:24:48 Srednjeevropski poletni čas je Chen-Yu Tsai napisal(a):
> From: Chen-Yu Tsai <wens@csie.org>
> 
> The Radxa Cubie A5E has empty pads for a 32.768 KHz crystal, but it is
> left unpopulated, as per the schematics and seen on board images. A dead
> give away is the RTC's LOSC auto switch register showing the external
> OSC to be abnormal.
> 
> Drop the external crystal from the device tree. It was not referenced
> anyway.
> 
> Fixes: c2520cd032ae ("arm64: dts: allwinner: a523: add Radxa A5E support")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> ---
>  arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts | 7 -------
>  1 file changed, 7 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts b/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
> index 71074b072184..e333bbaf01d3 100644
> --- a/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
> +++ b/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts
> @@ -24,13 +24,6 @@ chosen {
>  		stdout-path = "serial0:115200n8";
>  	};
>  
> -	ext_osc32k: ext-osc32k-clk {
> -		#clock-cells = <0>;
> -		compatible = "fixed-clock";
> -		clock-frequency = <32768>;
> -		clock-output-names = "ext_osc32k";
> -	};
> -
>  	leds {
>  		compatible = "gpio-leds";
>  
> 

Re: [PATCH 1/3] arm64: dts: allwinner: a527: cubie-a5e: Drop external 32.768 KHz crystal

[Chen-Yu Tsai]

On Sat, 13 Sep 2025 18:24:48 +0800, Chen-Yu Tsai wrote:
> The Radxa Cubie A5E has empty pads for a 32.768 KHz crystal, but it is
> left unpopulated, as per the schematics and seen on board images. A dead
> give away is the RTC's LOSC auto switch register showing the external
> OSC to be abnormal.
> 
> Drop the external crystal from the device tree. It was not referenced
> anyway.
> 
> [...]

Applied to sunxi/dt-for-6.18 in local tree, thanks!

[1/3] arm64: dts: allwinner: a527: cubie-a5e: Drop external 32.768 KHz crystal
      commit: 9f01e1e14e71defefcb4d6823b8476a15f3cf04a
[2/3] arm64: dts: allwinner: t527: avaota-a1: hook up external 32k crystal
      commit: 3d5e1ba00af8dd34ae1e573c2c07e00b5ec65267
[3/3] arm64: dts: allwinner: t527: orangepi-4a: hook up external 32k crystal
      commit: bd1ce7ef6aef4ee7349eb3124166e712693650ce

Best regards,
-- 
Chen-Yu Tsai <wens@csie.org>