[PATCH v2 2/3] arm64: dts: ti: k3-{j784s4-j742s2/j721s2}-mcu-wakeup: Add HSM M4F node

[Nishanth Menon]

On 16:17-20260106, Beleswar Padhi wrote:
> The TI K3 J721S2, J784S4 and J742S2 SoCs have a HSM (High Security
> Module) M4F core in the Wakeup Voltage Domain which could be used to run
> secure services like Authentication. Add Device Tree Node definitions
> for the HSM core in the respective SoC wakeup dtsi files.
> 
> Signed-off-by: Beleswar Padhi <b-padhi at ti.com>
> ---
> v2: Changelog:
> 1. None
> 
> Link to v1:
> https://lore.kernel.org/all/20251231165102.950644-3-b-padhi@ti.com/
> 
>  arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi  | 15 +++++++++++++++
>  .../ti/k3-j784s4-j742s2-mcu-wakeup-common.dtsi    | 15 +++++++++++++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
> index fd01437726ab4..c3d78d4a838a1 100644
> --- a/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
> @@ -766,4 +766,19 @@ mcu_watchdog1: watchdog at 40610000 {
>  		/* reserved for MCU_R5F0_1 */
>  		status = "reserved";
>  	};
> +
> +	hsm_m4fss: m4fss at 43c00000 {

You did fix this in the binding example.. but missed in dts.

The node name should use the generic type, not the instance name. It should
be "remoteproc at 43c00000", not "m4fss at 43c00000".

Additionally for the label, why not just use hsm: like we have for sms?

> +		compatible = "ti,hsm-m4fss";
> +		reg = <0x00 0x43c00000 0x00 0x20000>,
> +		      <0x00 0x43c20000 0x00 0x10000>,
> +		      <0x00 0x43c30000 0x00 0x10000>;

The total address range covered here is 0x43c00000-0x43c40000, which is
0x40000 bytes, matching the ranges entry. However, you're defining three
separate regions: 0x43c00000-0x43c20000 (0x20000), 0x43c20000-0x43c30000
(0x10000), and 0x43c30000-0x43c40000 (0x10000).

I assume you are doing this since the h/w integration could be
instantiated differently?


> +		reg-names = "sram0_0", "sram0_1", "sram1";
> +		resets = <&k3_reset 304 1>;
> +		firmware-name = "hsm.bin";

I am not a fan of putting firmware-name in SoC.dtsi - esp when it is
reserved, further, so far we have been using j722s-wkup-r5f0_0-fw and
so on.. which allows for firmware specific to SoC.. which kind of makes
sense here as well.

> +		ti,sci = <&sms>;
> +		ti,sci-dev-id = <304>;
> +		ti,sci-proc-ids = <0x80 0xff>;
> +		status = "disabled";

As usual, document why? Additionally, should this be reserved?

> +		bootph-pre-ram;

"standard property"

Documentation/devicetree/bindings/dts-coding-style.rst - note the order:
1. "compatible"
2. "reg"
3. "ranges"
4. Standard/common properties (defined by common bindings, e.g. without
   vendor-prefixes)
5. Vendor-specific properties
6. "status" (if applicable), preceded by a blank line if there is content
   before the property
7. Child nodes, where each node is preceded with a blank line
> +	};
>  };

Same for the rest of the patches and nodes

> diff --git a/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-mcu-wakeup-common.dtsi b/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-mcu-wakeup-common.dtsi
> index cc22bfb5f5996..42565f41b7bac 100644
> --- a/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-mcu-wakeup-common.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-j784s4-j742s2-mcu-wakeup-common.dtsi
> @@ -762,4 +762,19 @@ mcu_watchdog1: watchdog at 40610000 {
>  		/* reserved for MCU_R5F0_1 */
>  		status = "reserved";
>  	};
> +
> +	hsm_m4fss: m4fss at 43c00000 {
> +		compatible = "ti,hsm-m4fss";
> +		reg = <0x00 0x43c00000 0x00 0x20000>,
> +		      <0x00 0x43c20000 0x00 0x10000>,
> +		      <0x00 0x43c30000 0x00 0x10000>;
> +		reg-names = "sram0_0", "sram0_1", "sram1";
> +		resets = <&k3_reset 371 1>;
> +		firmware-name = "hsm.bin";
> +		ti,sci = <&sms>;
> +		ti,sci-dev-id = <371>;
> +		ti,sci-proc-ids = <0x80 0xff>;
> +		status = "disabled";
> +		bootph-pre-ram;
> +	};
>  };
> -- 
> 2.34.1
> 

-- 
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3  1A34 DDB5 849D 1736 249D
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