Re: [PATCH] arm64: dts: qcom: sm8750: Add adsp fastrpc support

[Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>]

On 5/9/2025 7:01 PM, Srinivas Kandagatla wrote:
> On 5/9/25 14:16, Alexey Klimov wrote:
>> On Fri May 2, 2025 at 11:51 AM BST, Srinivas Kandagatla wrote:
>>> On 5/2/25 02:15, Alexey Klimov wrote:
>>>> While at this, also add required memory region for fastrpc.
>>>>
>>>> Tested on sm8750-mtp device with adsprpdcd.
>>>>
>>>> Cc: Ekansh Gupta <quic_ekangupt@quicinc.com>
>>>> Cc: Srinivas Kandagatla <srini@kernel.org>
>>>> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>>> Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
>>>> ---
>>>>  arch/arm64/boot/dts/qcom/sm8750.dtsi | 70 ++++++++++++++++++++++++++++
>>>>  1 file changed, 70 insertions(+)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/qcom/sm8750.dtsi b/arch/arm64/boot/dts/qcom/sm8750.dtsi
>>>> index 149d2ed17641..48ee66125a89 100644
>>>> --- a/arch/arm64/boot/dts/qcom/sm8750.dtsi
>>>> +++ b/arch/arm64/boot/dts/qcom/sm8750.dtsi
>>>> @@ -7,6 +7,7 @@
>>>>  #include <dt-bindings/clock/qcom,sm8750-gcc.h>
>>>>  #include <dt-bindings/clock/qcom,sm8750-tcsr.h>
>>>>  #include <dt-bindings/dma/qcom-gpi.h>
>>>> +#include <dt-bindings/firmware/qcom,scm.h>
>>>>  #include <dt-bindings/interconnect/qcom,icc.h>
>>>>  #include <dt-bindings/interconnect/qcom,sm8750-rpmh.h>
>>>>  #include <dt-bindings/interrupt-controller/arm-gic.h>
>>>> @@ -523,6 +524,14 @@ llcc_lpi_mem: llcc-lpi@ff800000 {
>>>>  			reg = <0x0 0xff800000 0x0 0x800000>;
>>>>  			no-map;
>>>>  		};
>>>> +
>>>> +		adsp_rpc_remote_heap_mem: adsp-rpc-remote-heap {
>>>> +			compatible = "shared-dma-pool";
>>>> +			alloc-ranges = <0x0 0x00000000 0x0 0xffffffff>;
>>>> +			alignment = <0x0 0x400000>;
>>>> +			size = <0x0 0xc00000>;
>>>> +			reusable;
>>>> +		};
>>>>  	};
>>>>  
>>>>  	smp2p-adsp {
>>>> @@ -2237,6 +2246,67 @@ q6prmcc: clock-controller {
>>>>  						};
>>>>  					};
>>>>  				};
>>>> +
>>>> +				fastrpc {
>>>> +					compatible = "qcom,fastrpc";
>>>> +					qcom,glink-channels = "fastrpcglink-apps-dsp";
>>>> +					label = "adsp";
>>>> +					memory-region = <&adsp_rpc_remote_heap_mem>;
>>>> +					qcom,vmids = <QCOM_SCM_VMID_LPASS
>>>> +						      QCOM_SCM_VMID_ADSP_HEAP>;
>>>> +					qcom,non-secure-domain;
>>> Any reason why we what to mark adsp as non-secure domain by default?
>> No particular reason. That's what we went with on other platforms, so this just follows
>> the same. If we need to update this flag to secure then most likely that should be done
>> for some other platforms as well.
>> The only thing I know that adsprpcd + audio pd works with non-secure flag.
>> I can try to re-test with secure flag.
>>
> I know that this is loosely enforced in the current state.
> We want adsp to be always in secure mode as it will have access to some
> of the IP blocks inside the DSP other than just hexagon compute.
>
>
>> Ekansh, do we have any preference here regarding this?
> @Ekansh, we should provide that clarity in dt bindings.

qcom,non-secure-domain should actually represent the DSPs supporting
unsigned PD(low privileged) and secure only supports Signed PD(privileged).
I had added some details here[1] also.

I agree with Srini's point about providing clarity in dt bindings for this
property. I'll send some changes for this.

[1] https://lore.kernel.org/all/412fe24e-ce70-4733-ace5-d3fbe43476c4@oss.qualcomm.com/

//Ekansh

>
> --srini
>> Best regards,
>> Alexey