Re: [PATCH v8] arm64: dts: qcom: kodiak: Add EL2 overlay

[Miaoqing Pan <miaoqing.pan@oss.qualcomm.com>]

On 6/24/2026 2:39 PM, Mukesh Ojha wrote:
> 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.
> And for wifi to work wpss copy engine memory need to be mapped for
> WPSS firmware to work which is aligning with sc7280 chrome.
>
> [1]
> https://docs.qualcomm.com/bundle/publicresource/topics/80-70020-4/boot-developer-touchpoints.html#uefi
>
> Co-developed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
> ---
> Changes in v8: https://lore.kernel.org/lkml/20260522115936.201208-2-sumit.garg@kernel.org/
>   - Added a wpss copy engine memory similar to chrome for Wifi to work.
>   - WPSS does not have firmware Stream, so that was removed.
>   - Added wifi streams similar to chrome for wifi to work.
>   - Removed this patch from Generic Pas patch series, can be followed
>     separately.
>   - Moved Sumit as co-author as part of modification done to the patch
>     in the past.
>   - Added some more kodiak's board variants in the makefile.
>
> Changes in v1-v7:
>   - mpss was disabled and will be enabled once the dependencies patches
>    get merged.
>
>   arch/arm64/boot/dts/qcom/Makefile        | 12 ++++++
>   arch/arm64/boot/dts/qcom/kodiak-el2.dtso | 52 ++++++++++++++++++++++++
>   arch/arm64/boot/dts/qcom/kodiak.dtsi     |  2 +-
>   3 files changed, 65 insertions(+), 1 deletion(-)
>   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 6f33c4e2f09c..d2cee1190954 100644
> --- a/arch/arm64/boot/dts/qcom/Makefile
> +++ b/arch/arm64/boot/dts/qcom/Makefile
> @@ -164,7 +164,11 @@ purwa-iot-evk-el2-dtbs	:= purwa-iot-evk.dtb x1-el2.dtbo
>   
>   dtb-$(CONFIG_ARCH_QCOM)	+= purwa-iot-evk-el2.dtb
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcm6490-fairphone-fp5.dtb
> +
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcm6490-idp.dtb
> +qcm6490-idp-el2-dtbs := qcm6490-idp.dtb kodiak-el2.dtbo
> +dtb-$(CONFIG_ARCH_QCOM)	+= qcm6490-idp-el2.dtb
> +
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcm6490-particle-tachyon.dtb
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcm6490-shift-otter.dtb
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs404-evb-1000.dtb
> @@ -176,12 +180,20 @@ qcs615-ride-el2-dtbs := qcs615-ride.dtb talos-el2.dtbo
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs615-ride-el2.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-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-el2.dtb
>   
>   qcs6490-rb3gen2-vision-mezzanine-dtbs := qcs6490-rb3gen2.dtb qcs6490-rb3gen2-vision-mezzanine.dtbo
>   qcs6490-rb3gen2-industrial-mezzanine-dtbs := qcs6490-rb3gen2.dtb qcs6490-rb3gen2-industrial-mezzanine.dtbo
>   
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-industrial-mezzanine.dtb
> +qcs6490-rb3gen2-industrial-mezzanine-el2-dtbs := qcs6490-rb3gen2-industrial-mezzanine.dtb kodiak-el2.dtbo
> +dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-industrial-mezzanine-el2.dtb
> +
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-vision-mezzanine.dtb
> +qcs6490-rb3gen2-vision-mezzanine-el2-dtbs := qcs6490-rb3gen2-vision-mezzanine.dtb kodiak-el2.dtbo
> +dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-vision-mezzanine-el2.dtb
> +
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-thundercomm-minipc-g1iot.dtb
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-thundercomm-rubikpi3.dtb
>   dtb-$(CONFIG_ARCH_QCOM)	+= qcs8300-ride.dtb
> 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..91e4cda45b49
> --- /dev/null
> +++ b/arch/arm64/boot/dts/qcom/kodiak-el2.dtso
> @@ -0,0 +1,52 @@
> +// 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_mpss {
> +	status = "disabled";
> +};
> +
> +&reserved_memory {
> +	#address-cells = <2>;
> +	#size-cells = <2>;
> +
> +	wlan_ce_mem: wlan-ce@4cd000 {
> +		no-map;
> +		reg = <0x0 0x004cd000 0x0 0x1000>;
> +	};
> +};
> +
Is it necessary to redefine |wlan_ce_mem|? Can we consider updating 
|qcs6490-rb3gen2.dts|?
I have verified that with the following changes, *NON-KVM works fine*, 
and |wlan_ce_mem| is only used by the WCN6750 firmware.

--- a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
+++ b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
@@ -26,7 +26,6 @@
/delete-node/ &adsp_mem;
/delete-node/ &cdsp_mem;
/delete-node/ &video_mem;
-/delete-node/ &wlan_ce_mem;
/delete-node/ &wpss_mem;
/delete-node/ &xbl_mem;

@@ -1686,7 +1685,6 @@ &venus {
};

&wifi {
-       memory-region = <&wlan_fw_mem>;
         qcom,calibration-variant = "Qualcomm_rb3gen2";


> +&venus {
> +	status = "disabled";
> +};
> +
> +&watchdog {
> +	status = "okay";
> +};
> +
> +&wifi {
> +	memory-region = <&wlan_fw_mem>, <&wlan_ce_mem>;
> +	status = "okay";
> +
> +	wifi-firmware {
> +		iommus = <&apps_smmu 0x1c02 0x1>;
> +	};
> +};
> diff --git a/arch/arm64/boot/dts/qcom/kodiak.dtsi b/arch/arm64/boot/dts/qcom/kodiak.dtsi
> index fa540d8c2615..2486d15fa2ba 100644
> --- a/arch/arm64/boot/dts/qcom/kodiak.dtsi
> +++ b/arch/arm64/boot/dts/qcom/kodiak.dtsi
> @@ -91,7 +91,7 @@ sleep_clk: sleep-clk {
>   		};
>   	};
>   
> -	reserved-memory {
> +	reserved_memory: reserved-memory {
>   		#address-cells = <2>;
>   		#size-cells = <2>;
>   		ranges;