Re: [PATCH v7 10/10] arm64: dts: rockchip: rk3576-rock-4d: enable NPU

Hi Jiaxing,

On 8/12/2026 5:41 PM, Jiaxing Hu wrote:
> Enable rknn_core_0 and its IOMMU on the Radxa ROCK 4D and supply the
> core from vdd_npu_s0.
> 
> The supply is marked always-on because the NPU power domains are what
> gate the block here, and dropping the rail underneath them takes an
> async SError on the next power-on rather than a clean retry. Only
> rknn_core_0 is enabled: the driver binds one core per node and the
> second core is left to whoever can test it.
> 
> Signed-off-by: Jiaxing Hu <[email protected]>
> ---
>  arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts b/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
> index 272af1012..965e0906b 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
> +++ b/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
> @@ -442,6 +442,7 @@ regulator-state-mem {
>  			};
>  
>  			vdd_npu_s0: dcdc-reg2 {
> +				regulator-always-on;
>  				regulator-boot-on;
>  				regulator-enable-ramp-delay = <400>;
>  				regulator-min-microvolt = <550000>;
> @@ -869,3 +870,12 @@ vp0_out_hdmi: endpoint@ROCKCHIP_VOP2_EP_HDMI0 {
>  		remote-endpoint = <&hdmi_in_vp0>;
>  	};
>  };
> +
> +&rknn_core_0 {
> +	npu-supply = <&vdd_npu_s0>;

Out of curiosity, I searched for code about this supply in the rocket
driver and found nothing.

Then what is the consumer of this regulator? I have reason to suspect 
they were automatically disabled.


> +	status = "okay";
> +};
> +
> +&rknn_mmu_0 {
> +	status = "okay";
> +};

-- 
Best, 
Chaoyi