[PATCH V2 3/3] arm64: dts: nvidia: Add nodes for CMDQV

Ashish Mhetre amhetre at nvidia.com
Mon Dec 1 07:54:07 PST 2025


On 12/1/2025 7:41 PM, Thierry Reding wrote:
> On Mon, Dec 01, 2025 at 03:06:55PM +0530, Ashish Mhetre wrote:
>> On 11/25/2025 3:52 PM, Jon Hunter wrote:
>>>
>>> On 25/11/2025 07:16, Ashish Mhetre wrote:
>>>> The Command Queue Virtualization (CMDQV) hardware is part of the
>>>> SMMUv3 implementation on NVIDIA Tegra SoCs. It assists in
>>>> virtualizing the command queue for the SMMU.
>>>>
>>>> Update SMMU compatible strings to use nvidia,tegra264-smmu to enable
>>>> CMDQV support. Add device tree nodes for the CMDQV hardware and enable
>>>> them on the tegra264-p3834 platform where SMMUs are enabled. Each SMMU
>>>> instance is paired with its corresponding CMDQV instance via the
>>>> nvidia,cmdqv property.
>>>>
>>>> Signed-off-by: Ashish Mhetre <amhetre at nvidia.com>
>>>> ---
>>>>    .../arm64/boot/dts/nvidia/tegra264-p3834.dtsi |  8 +++
>>>>    arch/arm64/boot/dts/nvidia/tegra264.dtsi      | 55 +++++++++++++++++--
>>>>    2 files changed, 58 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
>>>> b/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
>>>> index 06795c82427a..375d122b92fa 100644
>>>> --- a/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
>>>> +++ b/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
>>>> @@ -26,5 +26,13 @@ iommu at 5000000 {
>>>>            iommu at 6000000 {
>>>>                status = "okay";
>>>>            };
>>>> +
>>>> +        cmdqv at 5200000 {
>>>> +            status = "okay";
>>>> +        };
>>> This needs to be ordered in the file according to its address.
>> Hi Jon, Thanks for the review.
>> cmdqv nodes follow same ordering as its corresponding iommu nodes.
>> I have added them immediately after corresponding iommu nodes.
> No, you didn't. It seems like you sorted by type and then address. But
> we always sort by address first. Type doesn't matter.
>
> This node belongs above the iommu at 6000000 node and after iommu at 5000000.
> The same ordering should be respected in the DTS include.
>
> Thierry

Oh, I got it. Thanks for clarification. I'll make these changes in v3.




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