Re: [PATCH v2 1/3] arm64: dts: qcom: sdm630/660: Add CDSP-related nodes

[Nickolay Goppen <setotau@mainlining.org>]

20.11.2025 07:55, Ekansh Gupta пишет:
>
> On 11/20/2025 1:58 AM, Srinivas Kandagatla wrote:
>> On 11/12/25 1:52 PM, Konrad Dybcio wrote:
>>> On 11/10/25 6:41 PM, Srinivas Kandagatla wrote:
>>>> On 11/3/25 12:52 PM, Konrad Dybcio wrote:
>>>>> On 10/31/25 12:30 PM, Nickolay Goppen wrote:
>>>>>> 24.10.2025 16:58, Nickolay Goppen пишет:
>>>>>>> 24.10.2025 11:28, Konrad Dybcio пишет:
>>>>>>>> On 10/23/25 9:51 PM, Nickolay Goppen wrote:
>>>>>>>>> In order to enable CDSP support for SDM660 SoC:
>>>>>>>>>    * add shared memory p2p nodes for CDSP
>>>>>>>>>    * add CDSP-specific smmu node
>>>>>>>>>    * add CDSP peripheral image loader node
>>>>>>>>>
>>>>>>>>> Memory region for CDSP in SDM660 occupies the same spot as
>>>>>>>>> TZ buffer mem defined in sdm630.dtsi (which does not have CDSP).
>>>>>>>>> In sdm660.dtsi replace buffer_mem inherited from SDM630 with
>>>>>>>>> cdsp_region, which is also larger in size.
>>>>>>>>>
>>>>>>>>> SDM636 also doesn't have CDSP, so remove inherited from sdm660.dtsi
>>>>>>>>> related nodes and add buffer_mem back.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Nickolay Goppen <setotau@mainlining.org>
>>>>>>>>> ---
>>>>>>>> [...]
>>>>>>>>
>>>>>>>>> +            label = "turing";
>>>>>>>> "cdsp"
>>>>>>> Ok, I'll change this in the next revision.
>>>>>>>>> +            mboxes = <&apcs_glb 29>;
>>>>>>>>> +            qcom,remote-pid = <5>;
>>>>>>>>> +
>>>>>>>>> +            fastrpc {
>>>>>>>>> +                compatible = "qcom,fastrpc";
>>>>>>>>> +                qcom,glink-channels = "fastrpcglink-apps-dsp";
>>>>>>>>> +                label = "cdsp";
>>>>>>>>> +                qcom,non-secure-domain;
>>>>>>>> This shouldn't matter, both a secure and a non-secure device is
>>>>>>>> created for CDSP
>>>>>>> I've added this property, because it is used in other SoC's, such as SDM845 and SM6115 for both ADSP and CDSP
>>>>>> Is this property not neccessary anymore?
>>>>> +Srini?
>>>> That is true, we do not require this for CDSP, as CDSP allows both
>>>> unsigned and signed loading, we create both secured and non-secure node
>>>> by default. May be we can provide that clarity in yaml bindings so that
>>>> it gets caught during dtb checks.
>>>>
>>>>
>>>> However in ADSP case, we only support singed modules, due to historical
>>>> reasons how this driver evolved over years, we have this flag to allow
>>>> compatiblity for such users.
>>> Does that mean that we can only load signed modules on the ADSP, but
>>> the driver behavior was previously such that unsigned modules were
>>> allowed (which was presumably fine on devboards, but not on fused
>>> devices)?
>> Yes, its true that we allowed full access to adsp device nodes when we
>> first started upstreaming fastrpc driver.
>>
>> irrespective of the board only signed modules are supported on the ADSP.
>> I think there was one version of SoC i think 8016 or some older one
>> which had adsp with hvx which can load unsigned modules for compute
>> usecase only.
>>
>> I have added @Ekansh for more clarity.
>>
>> --srini
> For all the available platforms, ADSP supports only signed modules. Unsigned
> modules(as well as signed) are supported by CDSP and GDSP subsystems.
>
> qcom,non-secure-domain property marks the corresponding DSP as non-secure DSP.
> The implications of adding this property would be the following:
> on ADSP, SDSP, MDSP:
> - Only non-secure device node(/dev/fastrpc-Xdsp) is created.
> - Non-secure device node can be used for signed DSP PD offload.
>
> on CDSP, GDSP:
> - Both secure(/dev/fastrpc-Xdsp-secure) and non-secure(/dev/fastrpc-Xdsp) devices
>    are created, regardless of this property.
> - Both the nodes can be used for signed and unsigned DSP PD offload.
>
> Note: If the property is not added for CDSP/GDSP, only secure device node can
> be used for signed PD offload, if non-secure device is used, the request gets
> rejected[1].
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/misc/fastrpc.c#n1245
>
> //Ekansh
Does this mean that the qcom,non-secure-domain property should be 
dropped from both nodes?
>>
>>> Konrad

-- 
Best regards,
Nickolay