Re: [PATCH v7 01/15] arm64: dts: qcom: kodiak: Add EL2 overlay
From: Mukesh Ojha
Date: Tue Jun 23 2026 - 12:32:40 EST
On Fri, May 22, 2026 at 05:29:22PM +0530, Sumit Garg wrote:
> From: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>
>
> All the existing variants Kodiak boards are using Gunyah hypervisor
> which means that, so far, Linux-based OS could only boot in EL1 on those
> devices. However, it is possible for us to boot Linux at EL2 on these
> devices [1].
>
> When running under Gunyah, the remote processor firmware IOMMU
> streams are controlled by Gunyah. However, without Gunyah, the IOMMU is
> managed by the consumer of this DeviceTree. Therefore, describe the
> firmware streams for each remote processor.
>
> Add a EL2-specific DT overlay and apply it to Kodiak IOT variant
> devices to create -el2.dtb for each of them alongside "normal" dtb.
>
> Note that modem and media subsystems haven't been supported yet due
> to missing dependencies. For GPU to work, zap shader is disabled and
> in EL2 mode the kernel owns hardware watchdog which is enabled here.
>
> [1]
> https://docs.qualcomm.com/bundle/publicresource/topics/80-70020-4/boot-developer-touchpoints.html#uefi
>
> Signed-off-by: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>
> [SG: watchdog and modem fixup]
> Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxxxxxxxx>
As discussed internally, I will be taking this patch separately and you
can drop this from series.
--
-Mukesh Ojha