Re: [PATCH v2 01/15] arm64: dts: qcom: kodiak: Add EL2 overlay

Mukesh Ojha
2026-03-13T06:05:10Z

On Thu, Mar 12, 2026 at 11:57:42AM +0530, Sumit Garg wrote:
> From: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
>
> 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.
>
> [1]
> https://docs.qualcomm.com/bundle/publicresource/topics/80-70020-4/boot-developer-touchpoints.html#uefi
>
> Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
> [SG: watchdog fixup]
> Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> ---
> arch/arm64/boot/dts/qcom/Makefile | 2 ++
> arch/arm64/boot/dts/qcom/kodiak-el2.dtso | 35 ++++++++++++++++++++++++
> 2 files changed, 37 insertions(+)
> create mode 100644 arch/arm64/boot/dts/qcom/kodiak-el2.dtso
>
> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
> index f80b5d9cf1e8..09a7f943190e 100644
> --- a/arch/arm64/boot/dts/qcom/Makefile
> +++ b/arch/arm64/boot/dts/qcom/Makefile
> @@ -139,6 +139,8 @@ dtb-$(CONFIG_ARCH_QCOM) += qcs404-evb-4000.dtb
> dtb-$(CONFIG_ARCH_QCOM) += qcs615-ride.dtb
> dtb-$(CONFIG_ARCH_QCOM) += qcs6490-radxa-dragon-q6a.dtb
> dtb-$(CONFIG_ARCH_QCOM) += qcs6490-rb3gen2.dtb
> +qcs6490-rb3gen2-el2-dtbs := qcs6490-rb3gen2.dtb kodiak-el2.dtbo
> +dtb-$(CONFIG_ARCH_QCOM) += qcs6490-rb3gen2-el2.dtb

We may need to add for couple of more variants..

>
> qcs6490-rb3gen2-vision-mezzanine-dtbs := qcs6490-rb3gen2.dtb qcs6490-rb3gen2-vision-mezzanine.dtbo
> qcs6490-rb3gen2-industrial-mezzanine-dtbs := qcs6490-rb3gen2.dtb qcs6490-rb3gen2-industrial-mezzanine.dtbo
> diff --git a/arch/arm64/boot/dts/qcom/kodiak-el2.dtso b/arch/arm64/boot/dts/qcom/kodiak-el2.dtso
> new file mode 100644
> index 000000000000..0b3a69a0d765
> --- /dev/null
> +++ b/arch/arm64/boot/dts/qcom/kodiak-el2.dtso
> @@ -0,0 +1,35 @@
> +// SPDX-License-Identifier: BSD-3-Clause
> +/*
> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> + *
> + * Kodiak specific modifications required to boot in EL2.
> + */
> +
> +
> +/dts-v1/;
> +/plugin/;
> +
> +&gpu_zap_shader {
> + status = "disabled";
> +};
> +
> +&remoteproc_adsp {
> + iommus = <&apps_smmu 0x1800 0x0>;
> +};
> +
> +&remoteproc_cdsp {
> + iommus = <&apps_smmu 0x11a0 0x0400>;
> +};
> +
> +&remoteproc_wpss {
> + iommus = <&apps_smmu 0x1c03 0x1>,
> + <&apps_smmu 0x1c83 0x1>;
> +};
> +
> +&venus {
> + status = "disabled";
> +};
> +
> +&watchdog {
> + status = "okay";
> +};

rb3gen2 has modem as well, did we test that as well ?

--
-Mukesh Ojha