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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z6zGLn3B6SVXhTV1@lizhi-Precision-Tower-5810>
Date: Wed, 12 Feb 2025 11:02:54 -0500
From: Frank Li <Frank.li@....com>
To: Daniel Baluta <daniel.baluta@....com>
Cc: shawnguo@...nel.org, robh@...nel.org, s.hauer@...gutronix.de,
	kernel@...gutronix.de, krzk+dt@...nel.org, conor+dt@...nel.org,
	festevam@...il.com, devicetree@...r.kernel.org, imx@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	aisheng.dong@....com, daniel.baluta@...il.com,
	laurentiu.mihalcea@....com, shengjiu.wang@....com,
	iuliana.prodan@....com, a.fatoum@...gutronix.de,
	Peng Fan <peng.fan@....com>
Subject: Re: [PATCH v4 5/6] arm64: dts: imx8mp: Add fsl,dsp-ctrl property for
 dsp

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@....com>
> Reviewed-by: Peng Fan <peng.fan@....com>
> Signed-off-by: Daniel Baluta <daniel.baluta@....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@...10000 {
>  			};
>
>  			audio_blk_ctrl: clock-controller@...20000 {
> -				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@...e8000 {
>  			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
>