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

["Jernej Škrabec" <jernej.skrabec@gmail.com>]

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>;
>