Re: [PATCH v3 RESEND 3/5] arm64: dts: qcom: Add device tree for Nord SA8797P SoC

[Dmitry Baryshkov]

On Wed, Jul 08, 2026 at 08:19:06PM -0700, Deepti Jaggi wrote:
> 
> 
> On 7/6/2026 8:38 PM, Pavan Kondeti wrote:
> > On Mon, Jul 06, 2026 at 07:15:15PM -0700, Deepti Jaggi wrote:
> >>
> >>
> >> On 7/6/2026 6:57 AM, Pavan Kondeti wrote:
> >>> On Tue, May 26, 2026 at 01:12:58PM +0800, Shawn Guo wrote:
> >>>> diff --git a/arch/arm64/boot/dts/qcom/scmi-common.dtsi b/arch/arm64/boot/dts/qcom/scmi-common.dtsi
> >>>> new file mode 100644
> >>>> index 000000000000..0c7ffe9e415c
> >>>> --- /dev/null
> >>>> +++ b/arch/arm64/boot/dts/qcom/scmi-common.dtsi
> >>>> @@ -0,0 +1,1918 @@
> >>>> +// SPDX-License-Identifier: BSD-3-Clause
> >>>> +/*
> >>>> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> >>>> + */
> >>>> +
> >>>> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> >>>> +
> >>>> +&firmware {
> >>>> +	scmi0: scmi-0 {
> >>>> +		compatible = "qcom,scmi-smc";
> >>>> +		arm,smc-id = <0xc6008012>;
> >>>> +		shmem = <&shmem0>;
> >>>> +		interrupts = <GIC_SPI 963 IRQ_TYPE_EDGE_RISING>;
> >>>> +		interrupt-names = "a2p";
> >>>
> >>> I believe this interrupt source is GearVM firmware via Gunyah's
> >>> doorbell, correct? How do we know that scmi0 instance's interrupt 
> >>> is GIC_SPI#963? Are these assumed to be constant/fixed through out
> >>> the life time of this SoC?
> >>
> >> Yes, this interrupt is a Gunyah Rx doorbell VIRQ for SCMI a2p completion
> >> from GearVM to Linux. It is allocated by Gunyah RM from the platform's virtual
> >> IRQ range and patched into the DTB by Linux bootloader at boot stage.
> >>  
> >>>
> > 
> > Thanks Deepti. IIUC, GIC_SPI#963 may be overridden by bootloader and
> > potentially this IRQ can change across runs or when firmware is changed
> > etc. The interrupt property is a place holder. can you confirm please?
> >
> 
> IRQ will not change across runs , it may change with firmware updates.

If it is provided by the firmware, why is it a part of the DT?

-- 
With best wishes
Dmitry