Re: [PATCH v5 2/3] arm64: dts: qcom: Introduce sa8255p SoC

[Deepti Jaggi]

On 3/11/2026 6:41 AM, Konrad Dybcio wrote:
> On 3/5/26 5:28 AM, Deepti Jaggi wrote:
>> From: Nikunj Kela <quic_nkela@xxxxxxxxxxx>
>>
>> Introduce base device tree support for sa8255p Qualcomm's automotive
>> infotainment SoC. The base dt file describes core SoC components- CPUs,
>> CPU map, ipcc, QUP,  geni UART, interrupt controller, TLMM, reserved
>> memory, SMMU, firmware scm, scmi, watchdog, SRAM, PSCI, ufs, pcie, pmu
>> nodes and enable booting to shell with ramdisk.
>>
>> The Qualcomm automotive sa8255p SoC utilizes firmware to configure
>> platform resources such as clocks, interconnects, and TLMM. Device drivers
>> request these resources through the SCMI power,reset and performance
>> protocols. Assign each device driver a dedicated SCMI channel and Tx/Rx
>> doorbells to support parallel resource requests and aggregation in the
>> SCMI platform server. Operate the SCMI server stack in an SMP-enabled VM,
>> using the Qualcomm SMC/HVC transport driver for communication.
>>
>> Group resource operations to improve abstraction and reduce the number of
>> SCMI requests. Follow the SCMI-based resource management approach
>> demonstrated by Qualcomm at LinaroConnect 2024.[1]
>>
>> Limit initial support to basic platform resources, serial console, ufs
>> and pcie.Defer enabling USB, and Ethernet to subsequent updates.
>>
>> [1]: https://resources.linaro.org/en/resource/wfnfEwBhRjLV1PEAJoDDte
>>
>> Co-developed-by: Shazad Hussain <shazad.hussain@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Shazad Hussain <shazad.hussain@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Nikunj Kela <quic_nkela@xxxxxxxxxxx>
>> Co-developed-by: Deepti Jaggi <deepti.jaggi@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Deepti Jaggi <deepti.jaggi@xxxxxxxxxxxxxxxx>
>> ---
> [...]

Thanks for reviewing the series .

>> +		tsens2: thermal-sensor@c251000 {
>> +			compatible = "qcom,sa8255p-tsens", "qcom,tsens-v2";
>> +			reg = <0x0 0x0c251000 0x0 0x1ff>,
>> +			      <0x0 0x0c224000 0x0 0x8>;
> All TSENS regions are 0x1000-long
>
> [...]

Ack

>
>> +		tlmm: pinctrl@f000000 {
>> +			compatible = "qcom,sa8255p-tlmm", "qcom,sa8775p-tlmm";
>> +			reg = <0x0 0x0f000000 0x0 0x1000000>;
>> +			interrupts = <GIC_SPI 208 IRQ_TYPE_LEVEL_HIGH>;
>> +			gpio-controller;
>> +			#gpio-cells = <2>;
>> +			interrupt-controller;
>> +			#interrupt-cells = <2>;
>> +			gpio-ranges = <&tlmm 0 0 149>;
>> +			wakeup-parent = <&pdc>;
>> +		};
> Praveen suggested GPIOs are not controlled by Linux:
>
> https://lore.kernel.org/linux-arm-msm/12063990-70fe-4faf-89fa-c74c7bd97f42@xxxxxxxxxxxxxxxx/
>
> Could you comment on this?
>
> [...]

For buses,FW is handling, but for PCIe and ethernet , pin configuration is controlled by Linux. 

>
>> +		aoss-0-thermal {
>> +			thermal-sensors = <&tsens0 0>;
> Is Linux going to act on any of these thermal trips?
>
> Konrad

Thanks,
Deepti