[PATCH v4 5/6] arm64: dts: imx8mp: Add fsl,dsp-ctrl property for dsp

[Frank Li]

On Wed, Feb 12, 2025 at 10:52:21AM +0200, Daniel Baluta wrote:
> Audio block control contains a set of registers and some of them used for
> DSP configuration.
>
> Drivers (rproc, SOF) are using fsl,dsp-ctrl property in order to control
> the DSP, particularly for Run/Stall bit.
>
> Note that audio block control doesn't offer the functionality to reset
> thte DSP. Reset is done via DAP interface.
>
> Reviewed-by: Iuliana Prodan <iuliana.prodan at nxp.com>
> Reviewed-by: Peng Fan <peng.fan at nxp.com>
> Signed-off-by: Daniel Baluta <daniel.baluta at nxp.com>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 14cfbd228b45..46b33fbb9bd1 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -1609,7 +1609,7 @@ sdma2: dma-controller at 30e10000 {
>  			};
>
>  			audio_blk_ctrl: clock-controller at 30e20000 {
> -				compatible = "fsl,imx8mp-audio-blk-ctrl";
> +				compatible = "fsl,imx8mp-audio-blk-ctrl", "syscon";
>  				reg = <0x30e20000 0x10000>;
>  				#clock-cells = <1>;
>  				#reset-cells = <1>;
> @@ -2425,6 +2425,7 @@ dsp: dsp at 3b6e8000 {
>  			mboxes = <&mu2 0 0>, <&mu2 1 0>, <&mu2 3 0>;
>  			firmware-name = "imx/dsp/hifi4.bin";
>  			memory-region = <&dsp_reserved>;
> +			fsl,dsp-ctrl = <&audio_blk_ctrl>;

I think kk's comments in v3

"This should have been implemented as reset controller, not syscon. It's
really poor choice to call everything syscon. It does not scale, does
not provide you runtime PM or probe ordering (device links). Quick look
at your drivers suggest that you have exacvtly that problems."

The above is quite good suggestion.

Your reply "But for Run/Stall bits we need to use a syscon.",

Run/Stall actually is reset, Most system, release reset signal means dsp/core
RUN.

Frank

>  			status = "disabled";
>  		};
>  	};
> --
> 2.43.0
>