All the Monaco IOT variants 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 Monaco 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>
---
 arch/arm64/boot/dts/qcom/Makefile        |  8 ++++++++
 arch/arm64/boot/dts/qcom/monaco-el2.dtso | 29 +++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
index f80b5d9cf1e8..cbf7d89e432c 100644
--- a/arch/arm64/boot/dts/qcom/Makefile
+++ b/arch/arm64/boot/dts/qcom/Makefile
@@ -45,6 +45,10 @@ lemans-evk-el2-dtbs := lemans-evk.dtb lemans-el2.dtbo
 dtb-$(CONFIG_ARCH_QCOM)	+= lemans-evk-el2.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= milos-fairphone-fp6.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= monaco-evk.dtb
+
+monaco-evk-el2-dtbs := monaco-evk.dtb monaco-el2.dtbo
+
+dtb-$(CONFIG_ARCH_QCOM)	+= monaco-evk-el2.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= msm8216-samsung-fortuna3g.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= msm8916-acer-a1-724.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= msm8916-alcatel-idol347.dtb
@@ -147,6 +151,10 @@ dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-industrial-mezzanine.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-rb3gen2-vision-mezzanine.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs6490-thundercomm-rubikpi3.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs8300-ride.dtb
+
+qcs8300-ride-el2-dtbs := qcs8300-ride.dtb monaco-el2.dtbo
+
+dtb-$(CONFIG_ARCH_QCOM)	+= qcs8300-ride-el2.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs8550-aim300-aiot.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs9100-ride.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= qcs9100-ride-r3.dtb
diff --git a/arch/arm64/boot/dts/qcom/monaco-el2.dtso b/arch/arm64/boot/dts/qcom/monaco-el2.dtso
new file mode 100644
index 000000000000..a7e3270f8609
--- /dev/null
+++ b/arch/arm64/boot/dts/qcom/monaco-el2.dtso
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
+ *
+ * Monaco specific modifications required to boot in EL2.
+ */
+
+/dts-v1/;
+/plugin/;
+
+&gpu_zap_shader {
+	status = "disabled";
+};
+
+&iris {
+	status = "disabled";
+};
+
+&remoteproc_adsp {
+	iommus = <&apps_smmu 0x2000 0x0>;
+};
+
+&remoteproc_cdsp {
+	iommus = <&apps_smmu 0x19c0 0x0400>;
+};
+
+&remoteproc_gpdsp {
+	iommus = <&apps_smmu 0x28a0 0x0>;
+};

-- 
2.50.1

On 1/27/26 12:43 PM, Mukesh Ojha wrote:
> All the Monaco IOT variants 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 Monaco 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>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad