Re: [PATCH 1/1] arm64: dts: rockchip: enable SCMI clk for RK3528 SoC

[Jonas Karlman <jonas@kwiboo.se>]

Hi Chukun,

On 2025-03-06 14:10, Chukun Pan wrote:
> Same as RK3568, RK3528 uses SCMI clk instead of ARMCLK.
> Add SCMI clk for CPU, GPU and RNG will also use it.
> 
> Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
> ---
>  arch/arm64/boot/dts/rockchip/rk3528.dtsi | 32 ++++++++++++++++++++++++
>  1 file changed, 32 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3528.dtsi b/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> index 0c0e7f151462..aa68c2fef2f3 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> @@ -59,6 +59,7 @@ cpu0: cpu@0 {
>  			reg = <0x0>;
>  			device_type = "cpu";
>  			enable-method = "psci";
> +			clocks = <&scmi_clk SCMI_CLK_CPU>;
>  		};
>  
>  		cpu1: cpu@1 {
> @@ -66,6 +67,7 @@ cpu1: cpu@1 {
>  			reg = <0x1>;
>  			device_type = "cpu";
>  			enable-method = "psci";
> +			clocks = <&scmi_clk SCMI_CLK_CPU>;
>  		};
>  
>  		cpu2: cpu@2 {
> @@ -73,6 +75,7 @@ cpu2: cpu@2 {
>  			reg = <0x2>;
>  			device_type = "cpu";
>  			enable-method = "psci";
> +			clocks = <&scmi_clk SCMI_CLK_CPU>;
>  		};
>  
>  		cpu3: cpu@3 {
> @@ -80,6 +83,22 @@ cpu3: cpu@3 {
>  			reg = <0x3>;
>  			device_type = "cpu";
>  			enable-method = "psci";
> +			clocks = <&scmi_clk SCMI_CLK_CPU>;
> +		};
> +	};
> +
> +	firmware {
> +		scmi: scmi {
> +			compatible = "arm,scmi-smc";
> +			arm,smc-id = <0x82000010>;
> +			shmem = <&scmi_shmem>;
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			scmi_clk: protocol@14 {
> +				reg = <0x14>;
> +				#clock-cells = <1>;
> +			};
>  		};
>  	};
>  
> @@ -110,6 +129,19 @@ gmac0_clk: clock-gmac50m {
>  		#clock-cells = <0>;
>  	};
>  
> +	sram@10f000 {
> +		compatible = "mmio-sram";
> +		reg = <0x0 0x0010f000 0x0 0x100>;
> +		ranges = <0 0x0 0x0010f000 0x100>;
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +
> +		scmi_shmem: sram@0 {
> +			compatible = "arm,scmi-shmem";
> +			reg = <0x0 0x100>;
> +		};
> +	};

This does not look correct, the shared memory is located in DRAM not in
SRAM. I used reserved-memory in my work-in-progress commit for adding
the GPU [1], something like, not sure if this is more correct:

	reserved-memory  {
		#address-cells = <2>;
		#size-cells = <2>;
		ranges;

		scmi_shmem: scmi-shmem@10f000 {
			compatible = "arm,scmi-shmem";
			reg = <0x0 0x0010f000 0x0 0x100>;
			no-map;
		};
	};

[1] https://github.com/Kwiboo/linux-rockchip/commit/f1cd58b2431a01e8cf6a430922204a71fee484f3

Regards,
Jonas

> +
>  	soc {
>  		compatible = "simple-bus";
>  		ranges = <0x0 0xfe000000 0x0 0xfe000000 0x0 0x2000000>;