[PATCH v2 0/2] arm64: dts: qcom: shikra: Add EL2 overlay for EVK variants

[PATCH v2 0/2] arm64: dts: qcom: shikra: Add EL2 overlay for EVK variants

[Komal Bajaj]

All existing Shikra EVK board variants boot Linux under a hypervisor,
which means Linux typically runs at EL1. For EL2 boot without the
hypervisor, remote processor firmware IOMMU streams must be described in
the DeviceTree consumed by Linux.

Add a Shikra EL2-specific DT overlay and wire it up in the Makefile to
produce -el2.dtb artifacts for the Shikra EVK variants alongside the
regular dtbs.

This series also relaxes the Qualcomm PAS remoteproc `iommus` item limit,
needed for Shikra EL2 remoteproc SMMU mappings.

Komal Bajaj (2):
  dt-bindings: remoteproc: qcom: Relax PAS iommus item limit
  arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

 .../bindings/remoteproc/qcom,pas-common.yaml       |  3 ++-
 arch/arm64/boot/dts/qcom/Makefile                  | 12 ++++++++++++
 arch/arm64/boot/dts/qcom/shikra-el2.dtso           | 23 +++++++++++++++++++++++
 3 files changed, 37 insertions(+), 1 deletion(-)

Signed-off-by: Komal Bajaj <komal.bajaj@oss.qualcomm.com>
---
Changes in v2:
- Relax the Qualcomm PAS remoteproc `iommus` item limit, needed for Shikra EL2 remoteproc SMMU mappings.
- Link to v1: https://lore.kernel.org/r/20260918-shikra-el2-v1-1-07bb072baa31@oss.qualcomm.com

---
Komal Bajaj (2):
      dt-bindings: remoteproc: qcom: Relax PAS iommus item limit
      arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

 .../bindings/remoteproc/qcom,pas-common.yaml       |  3 ++-
 arch/arm64/boot/dts/qcom/Makefile                  | 12 +++++++++++
 arch/arm64/boot/dts/qcom/shikra-el2.dtso           | 23 ++++++++++++++++++++++
 3 files changed, 37 insertions(+), 1 deletion(-)
---
base-commit: 6474fa070f2b8013b4b87350b775b8c3be6e8aac
change-id: 20260918-shikra-el2-ea8969385c3c

Best regards,
-- 
Komal Bajaj <komal.bajaj@oss.qualcomm.com>

[PATCH v2 1/2] dt-bindings: remoteproc: qcom: Relax PAS iommus item limit

[Komal Bajaj]

Some PAS users require more than one IOMMU mapping. Update
qcom,pas-common.yaml to allow up to three iommus entries so
PAS bindings can represent multi-stream mappings used by
platform device trees and avoid dt-schema array length failures.

Signed-off-by: Komal Bajaj <komal.bajaj@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
index f75cab6b4ed9..d56be38aec9e 100644
--- a/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
@@ -33,7 +33,8 @@ properties:
     maxItems: 6
 
   iommus:
-    maxItems: 1
+    minItems: 1
+    maxItems: 3
 
   power-domains:
     minItems: 1

-- 
2.34.1

Re: [PATCH v2 1/2] dt-bindings: remoteproc: qcom: Relax PAS iommus item limit

[Krzysztof Kozlowski]

On Wed, Sep 30, 2026 at 05:19:03PM +0530, Komal Bajaj wrote:
> Some PAS users require more than one IOMMU mapping. Update
> qcom,pas-common.yaml to allow up to three iommus entries so
> PAS bindings can represent multi-stream mappings used by
> platform device trees and avoid dt-schema array length failures.

This is incomplete. You just added two more iommus to all devices. You
need constraints and proper user of this.

Best regards,
Krzysztof

Re: [PATCH v2 1/2] dt-bindings: remoteproc: qcom: Relax PAS iommus item limit

[Komal Bajaj]

On 10/1/2026 2:03 PM, Krzysztof Kozlowski wrote:
> On Wed, Sep 30, 2026 at 05:19:03PM +0530, Komal Bajaj wrote:
>> Some PAS users require more than one IOMMU mapping. Update
>> qcom,pas-common.yaml to allow up to three iommus entries so
>> PAS bindings can represent multi-stream mappings used by
>> platform device trees and avoid dt-schema array length failures.
> This is incomplete. You just added two more iommus to all devices. You
> need constraints and proper user of this.

I see your point. This change relaxes constraint for all targets, which 
is broader than intended.
I will rework this and add required Shikra specific constraints in next 
revision.

Thanks
Komal

>
> Best regards,
> Krzysztof
>

[PATCH v2 2/2] arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

[Komal Bajaj]

Shikra boards currently boot Linux under a hypervisor, where the
remote processor firmware IOMMU streams are managed by the hypervisor.
When booting Linux directly at EL2 without the hypervisor, the IOMMU
is instead managed by the consumer of this DeviceTree, so the firmware
streams for each remote processor need to be described explicitly.

Add an EL2-specific DT overlay and apply it to all Shikra EVK variants
devices to produce an -el2.dtb alongside the "normal" dtb.

Co-developed-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
Signed-off-by: Komal Bajaj <komal.bajaj@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/Makefile        | 12 ++++++++++++
 arch/arm64/boot/dts/qcom/shikra-el2.dtso | 23 +++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
index 4e714251d5e6..634914b8f229 100644
--- a/arch/arm64/boot/dts/qcom/Makefile
+++ b/arch/arm64/boot/dts/qcom/Makefile
@@ -367,9 +367,20 @@ dtb-$(CONFIG_ARCH_QCOM)	+= sdm850-lenovo-yoga-c630.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdm850-samsung-w737.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sdx75-idp.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqm-evk.dtb
+
+shikra-cqm-evk-el2-dtbs	:= shikra-cqm-evk.dtb shikra-el2.dtbo
+dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqm-evk-el2.dtb
+
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqs-evk.dtb
+
+shikra-cqs-evk-el2-dtbs	:= shikra-cqs-evk.dtb shikra-el2.dtbo
+dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqs-evk-el2.dtb
+
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-iqs-evk.dtb
 
+shikra-iqs-evk-el2-dtbs	:= shikra-iqs-evk.dtb shikra-el2.dtbo
+dtb-$(CONFIG_ARCH_QCOM)	+= shikra-iqs-evk-el2.dtb
+
 shikra-cqm-evk-imx577-camera-dtbs	:= shikra-cqm-evk.dtb shikra-cqm-cqs-evk-imx577-camera.dtbo
 shikra-cqs-evk-imx577-camera-dtbs	:= shikra-cqs-evk.dtb shikra-cqm-cqs-evk-imx577-camera.dtbo
 shikra-iqs-evk-imx577-camera-dtbs	:= shikra-iqs-evk.dtb shikra-iqs-evk-imx577-camera.dtbo
@@ -377,6 +388,7 @@ shikra-iqs-evk-imx577-camera-dtbs	:= shikra-iqs-evk.dtb shikra-iqs-evk-imx577-ca
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqm-evk-imx577-camera.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqs-evk-imx577-camera.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= shikra-iqs-evk-imx577-camera.dtb
+
 dtb-$(CONFIG_ARCH_QCOM)	+= sm4250-oneplus-billie2.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sm4450-qrd.dtb
 dtb-$(CONFIG_ARCH_QCOM)	+= sm6115-fxtec-pro1x.dtb
diff --git a/arch/arm64/boot/dts/qcom/shikra-el2.dtso b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
new file mode 100644
index 000000000000..d2f3186bd47d
--- /dev/null
+++ b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
+ *
+ * Shikra specific modifications required to boot in EL2.
+ */
+
+/dts-v1/;
+/plugin/;
+
+&gpu_zap_shader {
+	status = "disabled";
+};
+
+&remoteproc_cdsp {
+	iommus = <&apps_smmu 0x0200 0x0>;
+};
+
+&remoteproc_lpaicp {
+	iommus = <&apps_smmu 0x0360 0x0005>,
+		 <&apps_smmu 0x0366 0x0000>,
+		 <&apps_smmu 0x00e7 0x0000>;
+};

-- 
2.34.1

Re: [PATCH v2 2/2] arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] Missing EL2 targets for camera EVK variants
- [Medium] Undocumented disablement of GPU zap shader in EL2 overlay
--

commit 07c9abdfac5fabfba8cfb72f094624db1d5cb41b
Author: Komal Bajaj <komal.bajaj@oss.qualcomm.com>

arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

This commit introduces an EL2-specific DeviceTree overlay for Shikra boards.
It explicitly configures the firmware IOMMU streams for remote processors,
allowing Linux to boot directly at EL2 without a hypervisor.

> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
> index 4e714251d5e6b..634914b8f229b 100644
> --- a/arch/arm64/boot/dts/qcom/Makefile
> +++ b/arch/arm64/boot/dts/qcom/Makefile
[ ... ]
> @@ -377,6 +388,7 @@ shikra-iqs-evk-imx577-camera-dtbs	:= shikra-iqs-evk.dtb shikra-iqs-evk-imx577-ca
>  dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqm-evk-imx577-camera.dtb
>  dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqs-evk-imx577-camera.dtb
>  dtb-$(CONFIG_ARCH_QCOM)	+= shikra-iqs-evk-imx577-camera.dtb

[Severity: Medium]
The commit message states the overlay is applied to "all Shikra EVK variants
devices", but are we missing the EL2 targets for these camera variants?

Without adding targets like shikra-cqm-evk-imx577-camera-el2-dtbs, the camera
variants cannot be built or booted natively at EL2.

> +
>  dtb-$(CONFIG_ARCH_QCOM)	+= sm4250-oneplus-billie2.dtb

[ ... ]

> diff --git a/arch/arm64/boot/dts/qcom/shikra-el2.dtso b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
> new file mode 100644
> index 0000000000000..d2f3186bd47db
> --- /dev/null
> +++ b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
> @@ -0,0 +1,23 @@
> +// SPDX-License-Identifier: BSD-3-Clause
> +/*
> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> + *
> + * Shikra specific modifications required to boot in EL2.
> + */
> +
> +/dts-v1/;
> +/plugin/;
> +
> +&gpu_zap_shader {
> +	status = "disabled";
> +};

[Severity: Medium]
Is it intended to disable the GPU zap shader in this overlay without
mentioning it in the commit message?

The commit message only describes adding remoteproc SMMU mappings. While
disabling the zap shader might be necessary for EL2 boot, this hardware
feature disablement is currently an undocumented side effect.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260930-shikra-el2-v2-0-f0822be5aaee@oss.qualcomm.com?part=2

Re: [PATCH v2 2/2] arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings

[Komal Bajaj]

On 9/30/2026 5:25 PM, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
> - [Medium] Missing EL2 targets for camera EVK variants
> - [Medium] Undocumented disablement of GPU zap shader in EL2 overlay
> --
>
> commit 07c9abdfac5fabfba8cfb72f094624db1d5cb41b
> Author: Komal Bajaj <komal.bajaj@oss.qualcomm.com>
>
> arm64: dts: qcom: shikra: Add EL2 overlay for remoteproc SMMU mappings
>
> This commit introduces an EL2-specific DeviceTree overlay for Shikra boards.
> It explicitly configures the firmware IOMMU streams for remote processors,
> allowing Linux to boot directly at EL2 without a hypervisor.
>
>> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
>> index 4e714251d5e6b..634914b8f229b 100644
>> --- a/arch/arm64/boot/dts/qcom/Makefile
>> +++ b/arch/arm64/boot/dts/qcom/Makefile
> [ ... ]
>> @@ -377,6 +388,7 @@ shikra-iqs-evk-imx577-camera-dtbs	:= shikra-iqs-evk.dtb shikra-iqs-evk-imx577-ca
>>   dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqm-evk-imx577-camera.dtb
>>   dtb-$(CONFIG_ARCH_QCOM)	+= shikra-cqs-evk-imx577-camera.dtb
>>   dtb-$(CONFIG_ARCH_QCOM)	+= shikra-iqs-evk-imx577-camera.dtb
> [Severity: Medium]
> The commit message states the overlay is applied to "all Shikra EVK variants
> devices", but are we missing the EL2 targets for these camera variants?
>
> Without adding targets like shikra-cqm-evk-imx577-camera-el2-dtbs, the camera
> variants cannot be built or booted natively at EL2.

Camera variants have not yet been validated in EL2, so the corresponding 
*-el2-dtbs targets were not added.
We will add them in a follow-up change once EL2 validation is completed.

>> +
>>   dtb-$(CONFIG_ARCH_QCOM)	+= sm4250-oneplus-billie2.dtb
> [ ... ]
>
>> diff --git a/arch/arm64/boot/dts/qcom/shikra-el2.dtso b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
>> new file mode 100644
>> index 0000000000000..d2f3186bd47db
>> --- /dev/null
>> +++ b/arch/arm64/boot/dts/qcom/shikra-el2.dtso
>> @@ -0,0 +1,23 @@
>> +// SPDX-License-Identifier: BSD-3-Clause
>> +/*
>> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
>> + *
>> + * Shikra specific modifications required to boot in EL2.
>> + */
>> +
>> +/dts-v1/;
>> +/plugin/;
>> +
>> +&gpu_zap_shader {
>> +	status = "disabled";
>> +};
> [Severity: Medium]
> Is it intended to disable the GPU zap shader in this overlay without
> mentioning it in the commit message?
>
> The commit message only describes adding remoteproc SMMU mappings. While
> disabling the zap shader might be necessary for EL2 boot, this hardware
> feature disablement is currently an undocumented side effect.

Zap shader is not required in EL2, as Linux can perform GPU zap sequence 
on its own. Disabling it is intentional.

Thanks
Komal