Re: [PATCH v3 2/4] dts: arm64: qcom: sdm845: add SLPI FastRPC support

[Konrad Dybcio]

On 30.03.2023 18:53, Dylan Van Assche wrote:
> Qualcomm SDM845 SoC features a SLPI DSP which uses FastRPC through
> an allocated memory region to load files from the host filesystem
> such as sensor configuration files.
> 
> Add a FastRPC node at /dev/fastrpc-sdsp and a DMA region, similar to
> downstream, to allow userspace to communicate with the SLPI via the
> FastRPC interface for initializing the sensors on the SLPI.
> 
> Signed-off-by: Dylan Van Assche <me@xxxxxxxxxxxxxxxxx>
> ---
>  arch/arm64/boot/dts/qcom/sdm845.dtsi | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sdm845.dtsi b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> index 3b547cb7aeb8..8ea4944f3ad6 100644
> --- a/arch/arm64/boot/dts/qcom/sdm845.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> @@ -878,6 +878,14 @@ mdata_mem: mpss-metadata {
>  			size = <0 0x4000>;
>  			no-map;
>  		};
> +
> +		fastrpc_mem: fastrpc {
> +			compatible = "shared-dma-pool";
> +			reusable;
Please move it last to get a nice reverse-Christmas-tree layout.

> +			alloc-ranges = <0 0x00000000 0 0xffffffff>;
Would there be any issues with it starting over (1<<31 - 1)?

> +			alignment = <0 0x400000>;
Please use 0x0 for the 0 here, as it's essentially reg.size with
size-cells = 2

> +			size = <0 0x1000000>;
Ditto

> +		};
>  	};
>  
>  	adsp_pas: remoteproc-adsp {
> @@ -3344,6 +3352,22 @@ glink-edge {
>  				label = "dsps";
>  				qcom,remote-pid = <3>;
>  				mboxes = <&apss_shared 24>;
> +
> +				fastrpc {
> +					compatible = "qcom,fastrpc";
> +					qcom,glink-channels = "fastrpcglink-apps-dsp";
> +					label = "sdsp";
> +					qcom,non-secure-domain;
> +					qcom,vmids = <0x3 0xF 0x5 0x6>;
Please use the recently-introduced header and depend on (and
make a patch atop)

https://lore.kernel.org/linux-arm-msm/8685b710-b74d-556a-815d-0ffef2b0eeff@xxxxxxxxxx/T/#t

Konrad

> +					memory-region = <&fastrpc_mem>;
> +					#address-cells = <1>;
> +					#size-cells = <0>;
> +
> +					compute-cb@0 {
> +						compatible = "qcom,fastrpc-compute-cb";
> +						reg = <0>;
> +					};
> +				};
>  			};
>  		};
>