Re: [PATCH v6 2/5] arm64: dts: qcom: ipq5424: Add the IMEM node

[Konrad Dybcio]

On 1/30/26 11:44 AM, Kathiravan Thirumoorthy wrote:
> Add the IMEM node to the device tree to extract debugging information
> like system restart reason, which is populated via IMEM. Define the
> IMEM region to enable this functionality.
> 
> As described, overall IMEM region is 112KB but only initial 4KB is
> accessible by all masters in the SoC.
> 
> Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@xxxxxxxxxxxxxxxx>
> ---
> Changes in v6:
> 	- move to mmio-sram and drop the Konrad's R-b tag
> Changes in v5:
> 	- No changes
> Changes in v4:
> 	- No changes
> Changes in v3:
> 	- Picked up the R-b tag
> Changes in v2:
> 	- Describe the entire IMEM region in the node
> 	- Explicitly call out that initial 4K only accessible by all
> 	  masters in the commit message
> ---
>  arch/arm64/boot/dts/qcom/ipq5424.dtsi | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/ipq5424.dtsi b/arch/arm64/boot/dts/qcom/ipq5424.dtsi
> index eb393f3fd728f0b2fc8cd93c849f8c170d76e312..90790f99f0597b63801d4e07b9b72cd372ad46d4 100644
> --- a/arch/arm64/boot/dts/qcom/ipq5424.dtsi
> +++ b/arch/arm64/boot/dts/qcom/ipq5424.dtsi
> @@ -697,6 +697,15 @@ ssphy_0: phy@7d000 {
>  			status = "disabled";
>  		};
>  
> +		sram@8600000 {
> +			compatible = "qcom,ipq5424-imem", "mmio-sram";
> +			reg = <0 0x08600000 0 0x1c000>;
> +			ranges = <0 0 0x08600000 0x1c000>;
> +
> +			#address-cells = <1>;
> +			#size-cells = <1>;

I think you may need to add 'no-memory-wc' too, in case someone uses
any of the sram functions on this in the future

Konrad