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

[Shazad Hussain]

On 3/11/2026 7:11 PM, 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>
> > ---
>
> [...]
>
> > +		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
>
> [...]
>
> > +		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?
>
> [...]
>
> > +		aoss-0-thermal {
> > +			thermal-sensors = <&tsens0 0>;
>
> Is Linux going to act on any of these thermal trips?

Yes Konard, it's going to act on these for thermal mitigations.

-Shazad

> Konrad