Subject: [PATCH v7 01/15] arm64: dts: qcom: kodiak: Add EL2 overlay

From: Sumit Garg <[email-masked]>
Date: Fri, 22 May 2026 17:29:22 +0530

From: Mukesh Ojha <[email-masked]>

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 <[email-masked]>
[SG: watchdog and modem fixup]
Signed-off-by: Sumit Garg <[email-masked]>
---
 arch/arm64/boot/dts/qcom/Makefile        |  2 ++
 arch/arm64/boot/dts/qcom/kodiak-el2.dtso | 39 ++++++++++++++++++++++++
 2 files changed, 41 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 795cee4757ab..d10490590e4c 100644
--- a/arch/arm64/boot/dts/qcom/Makefile
+++ b/arch/arm64/boot/dts/qcom/Makefile
@@ -176,6 +176,8 @@ 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
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..520ed582370d
--- /dev/null
+++ b/arch/arm64/boot/dts/qcom/kodiak-el2.dtso
@@ -0,0 +1,39 @@
+// 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";
+};
+
+&remoteproc_wpss {
+	iommus = <&apps_smmu 0x1c03 0x1>,
+		 <&apps_smmu 0x1c83 0x1>;
+};
+
+&venus {
+	status = "disabled";
+};
+
+&watchdog {
+	status = "okay";
+};
-- 
2.51.0