Re: [PATCH 7/8] arm64: dts: allwinner: a523: Add MCU PRCM CCU node

[Andre Przywara <andre.przywara@arm.com>]

On Sun, 31 Aug 2025 01:09:00 +0800
Chen-Yu Tsai <wens@kernel.org> wrote:

> From: Chen-Yu Tsai <wens@csie.org>
> 
> Add a device node for the third supported clock controller found in the
> A523 / T527 SoCs. This controller has clocks and resets for the RISC-V
> MCU, and others peripherals possibly meant to operate in low power mode
> driven by the MCU, such as audio interfaces, an audio DSP, and the NPU.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
>  .../arm64/boot/dts/allwinner/sun55i-a523.dtsi | 25 +++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi b/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> index 79bd9ce08c7c..b6e82d53af54 100644
> --- a/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> +++ b/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> @@ -4,8 +4,10 @@
>  #include <dt-bindings/interrupt-controller/arm-gic.h>
>  #include <dt-bindings/clock/sun6i-rtc.h>
>  #include <dt-bindings/clock/sun55i-a523-ccu.h>
> +#include <dt-bindings/clock/sun55i-a523-mcu-ccu.h>
>  #include <dt-bindings/clock/sun55i-a523-r-ccu.h>
>  #include <dt-bindings/reset/sun55i-a523-ccu.h>
> +#include <dt-bindings/reset/sun55i-a523-mcu-ccu.h>
>  #include <dt-bindings/reset/sun55i-a523-r-ccu.h>
>  #include <dt-bindings/power/allwinner,sun55i-a523-ppu.h>
>  #include <dt-bindings/power/allwinner,sun55i-a523-pck-600.h>
> @@ -825,6 +827,29 @@ rtc: rtc@7090000 {
>  			clock-names = "bus", "hosc", "ahb";
>  			#clock-cells = <1>;
>  		};
> +
> +		mcu_ccu: clock-controller@7102000 {
> +			compatible = "allwinner,sun55i-a523-mcu-ccu";
> +			reg = <0x7102000 0x164>;

There is a register at 0x164, and even though the Linux driver doesn't use
it, we should let the region cover it. Maybe even going to 0x200?

The clock names match up with those .fw_name used in the driver, so with
the region size fixed:

Reviewed-by: Andre Przywara <andre.przywara@arm.com>

Cheers,
Andre

> +			clocks = <&osc24M>,
> +				 <&rtc CLK_OSC32K>,
> +				 <&rtc CLK_IOSC>,
> +				 <&ccu CLK_PLL_AUDIO0_4X>,
> +				 <&ccu CLK_PLL_PERIPH0_300M>,
> +				 <&ccu CLK_DSP>,
> +				 <&r_ccu CLK_R_AHB>,
> +				 <&ccu CLK_MBUS>;
> +			clock-names = "hosc",
> +				      "losc",
> +				      "iosc",
> +				      "pll-audio0-4x",
> +				      "pll-periph0-300m",
> +				      "dsp",
> +				      "r-ahb",
> +				      "mbus";
> +			#clock-cells = <1>;
> +			#reset-cells = <1>;
> +		};
>  	};
>  
>  	thermal-zones {