Re: [PATCH 3/4] arm64: dts: qcom: sdm630: describe adsp_mem region properly

[Ekansh Gupta]

On 17-04-2026 23:06, Nickolay Goppen wrote:
> I'm assigning this region in the fourth patch
Okay, I see. Thanks for pointing it out.
> 
> 17 апреля 2026 г. 18:15:45 GMT+03:00, Ekansh Gupta <ekansh.gupta@xxxxxxxxxxxxxxxx> wrote:
>> On 15-04-2026 15:22, Konrad Dybcio wrote:
>>> On 4/15/26 11:40 AM, Nickolay Goppen wrote:
>>>> Downstream [1] this region is marked as shared and reusable so
>>>> describe it that way.
>>>>
>>>> [1]: https://github.com/xiaomi-sdm660/android_kernel_xiaomi_sdm660/blob/11-EAS/arch/arm/boot/dts/qcom/sdm660.dtsi#L448
>>>>
>>>> Signed-off-by: Nickolay Goppen <setotau@xxxxxxxxxxxxxx>
>>>> ---
>>>
>>> +Ekansh some insight, please?
>>>
>>> We're giving away that memory via qcom_scm_assign_mem() anyway
>>> and I would assume that making it not-"no-map" could introduce issues
>>> when the OS tries to access that region
>>>
>> With the current version and the upcoming planned enhancements, I don't
>> see any major benefits of making this as not-"no-map".
>>
>> With posted enhancements[1], the plan is to qcom_scm_assign_mem() the
>> entire memory-region to lpass VMIDs. and un-assign it only during
>> fastrpc_rpmsg_remove(). There have been implementation in downstream
>> where this memory is dumped in case of SSR or audio PDR using minidump,
>> so marking it `reusable` might make sense there, but that dump logic is
>> not added upstream.
>>
>> Upon checking the DT, I see a bigger problem here, this memory-region
>> looks to me unused, it's not added under fastrpc adsp node(ref. [2]).
>> Please correct me if I am wrong about this point.
>>
>> [1]
>> https://lore.kernel.org/all/20260409062617.1182-1-jianping.li@xxxxxxxxxxxxxxxx/
>> [2]
>> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/arch/arm64/boot/dts/qcom/lemans.dtsi#n7500
>>
>> //Ekansh
>>> Konrad
>>>
>>>
>>>>  arch/arm64/boot/dts/qcom/sdm630.dtsi | 3 ++-
>>>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/qcom/sdm630.dtsi b/arch/arm64/boot/dts/qcom/sdm630.dtsi
>>>> index 4b47efdb57b2..13094b5e9339 100644
>>>> --- a/arch/arm64/boot/dts/qcom/sdm630.dtsi
>>>> +++ b/arch/arm64/boot/dts/qcom/sdm630.dtsi
>>>> @@ -495,8 +495,9 @@ venus_region: venus@9f800000 {
>>>>  		};
>>>>  
>>>>  		adsp_mem: adsp-region@f6000000 {
>>>> +			compatible = "shared-dma-pool";
>>>>  			reg = <0x0 0xf6000000 0x0 0x800000>;
>>>> -			no-map;
>>>> +			reusable;
>>>>  		};
>>>>  
>>>>  		qseecom_mem: qseecom-region@f6800000 {
>>>>
> 
> Best regards
> Nickolay