[PATCH v2 00/12] media: iris: Migrate iommus to iris sub nodes

[PATCH v2 00/12] media: iris: Migrate iommus to iris sub nodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can 
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+

A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer inside the low 600 MB. Once an allocation lands below
that boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Daniel, who reported the crash issue, have also raised a patch to workaround
the issue. While the patch partially handles the limitation, it is inefficient
in a way that it keep iris hardwares away from using the 600MB address space
for all the different streams.

To address this limitation, the subset of stream/s are now represented as
sub nodes, so that they can be associated to the respective addressable
range.
In the past, this limitation was tried with iommu-map approach, with iris
driver dynamically creating the devices. The approach was later concluded
as an hack to avoid having sub nodes and NAKed by iommu maintainers.
It was discussed in detail in the discussion
https://lore.kernel.org/all/c7b956a9-d3e8-4e18-b780-5d08f5cd2ca1@kernel.org/

It was agreed by maintainers to proceed with sub node approach to address
the VPU hardware limitation.

Stable branch handling - one of the suggestion was to bring the 
workaround on mainline and stable, and later revert it on mainline and
apply this series. This would ideally breach the binding policy of
adding something to describe the hardware and then reverting it. As per 
binding maintainer, the approach is not acceptable.
This series can be applied to mainline as well as -stable, and in the process
if there are any conflicts in stable, I would resolve them.

Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
Changes in v2:
- Fixed sashiko issues.
- Moved subnodes into common schema (Dmitry)
- Kept the firmware name as the one defained earlier (Dmitry)
- Added dma-ranges to specify parent-child address translation
- Moved context bank hooks to VPU ops (Dmitry)
- Updated commit description.
- Link to v1: https://lore.kernel.org/r/20260709-vpu_iommu_iova_handling-v1-0-72bb62cb2dfd@oss.qualcomm.com

---
Vikash Garodia (12):
      dt-bindings: media: qcom,venus: Add context bank subnodes to common schema
      dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes
      media: iris: Add platform hooks for context bank device setup
      media: iris: Add helper to create a context bank device
      media: iris: Route buffers to the matching context bank device
      media: iris: Skip DMA mask setup when the core device has no IOMMU
      media: iris: Create pixel and non-pixel context banks on VPU3x
      arm64: dts: qcom: hamoa: Add Iris context bank subnodes
      arm64: dts: qcom: sm8550: Add Iris context bank subnodes
      arm64: dts: qcom: lemans: Add Iris context bank subnodes
      arm64: dts: qcom: monaco: Add Iris context bank subnodes
      arm64: dts: qcom: sm8650: Add Iris context bank subnodes

 .../bindings/media/qcom,sc7180-venus.yaml          | 15 -----
 .../bindings/media/qcom,sm8550-iris.yaml           | 18 +++++-
 .../bindings/media/qcom,venus-common.yaml          | 51 ++++++++++++++++
 arch/arm64/boot/dts/qcom/hamoa.dtsi                | 19 +++++-
 arch/arm64/boot/dts/qcom/lemans.dtsi               | 19 +++++-
 arch/arm64/boot/dts/qcom/monaco.dtsi               | 19 +++++-
 arch/arm64/boot/dts/qcom/qcs8550.dtsi              |  4 ++
 arch/arm64/boot/dts/qcom/sm8550.dtsi               | 19 +++++-
 arch/arm64/boot/dts/qcom/sm8650.dtsi               | 20 ++++++-
 drivers/media/platform/qcom/iris/iris_buffer.c     |  8 +--
 drivers/media/platform/qcom/iris/iris_core.h       |  4 ++
 drivers/media/platform/qcom/iris/iris_hfi_queue.c  | 16 ++---
 drivers/media/platform/qcom/iris/iris_probe.c      | 33 +++++++++--
 drivers/media/platform/qcom/iris/iris_resources.c  | 69 ++++++++++++++++++++++
 drivers/media/platform/qcom/iris/iris_resources.h  |  2 +
 drivers/media/platform/qcom/iris/iris_vidc.c       |  4 +-
 drivers/media/platform/qcom/iris/iris_vpu3x.c      | 38 ++++++++++++
 drivers/media/platform/qcom/iris/iris_vpu_common.h |  2 +
 18 files changed, 314 insertions(+), 46 deletions(-)
---
base-commit: 95d6a9ccef99117115e41e9adb271243bd5e985b
change-id: 20260701-vpu_iommu_iova_handling-556e969a1f1c

Best regards,
-- 
Vikash Garodia <vikash.garodia@oss.qualcomm.com>

[PATCH v2 01/12] dt-bindings: media: qcom,venus: Add context bank subnodes to common schema

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer inside the low 600 MB. Once an allocation lands below
that boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe each stream as its own context bank subnode instead, so that
each can be associated with the IOVA range its stream can actually
reach. This limitation applies to every VPU generation, so add the
subnodes to the common schema rather than to each SoC schema
individually. "video-firmware" moves here from qcom,sc7180-venus.yaml
for the same reason; it is the same kind of node and was already
duplicated per-SoC.
Adding the subnodes requires two supporting properties on the parent
video-codec node:
- '#address-cells' and '#size-cells', both fixed at 2. These do not
   describe registers on the codec node. They set the cell widths
   used when a reserved-memory node names one of these subnodes in an
   "iommu-addresses" entry: of_translate_dma_region() reads the
   address/size cell counts from the parent of the phandle target, not
   from the reserved-memory node. Pinning both to 2 lets a subnode be
   referenced with a full 64-bit IOVA base and length, and keeps the
   encoding identical across SoCs, whose buses vary between 1 and 2
   cells.
- "dma-ranges", empty "dma-ranges" states the intended translation:
   the subnode DMA address space maps 1:1 into the parent's, so an IOVA
   reservation written against a subnode needs no offset applied.
   of_translate_one() treats an empty "dma-ranges" as exactly that
   identity mapping.

The parent's "iommus" is kept as an alternative via "oneOf", so
platforms that have not been converted to subnodes still validate. New
platforms should use the subnode form.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 .../bindings/media/qcom,sc7180-venus.yaml          | 15 -------
 .../bindings/media/qcom,venus-common.yaml          | 51 ++++++++++++++++++++++
 2 files changed, 51 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml b/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
index b21bed314848480b82153e49602f0b19e08e7335..bfd8b1ad473128c974bce84639cb0aff59d8c2cc 100644
--- a/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
+++ b/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
@@ -91,21 +91,6 @@ properties:
     deprecated: true
     additionalProperties: false
 
-  video-firmware:
-    type: object
-    additionalProperties: false
-
-    description: |
-      Firmware subnode is needed when the platform does not
-      have TrustZone.
-
-    properties:
-      iommus:
-        maxItems: 1
-
-    required:
-      - iommus
-
 required:
   - compatible
   - power-domain-names
diff --git a/Documentation/devicetree/bindings/media/qcom,venus-common.yaml b/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
index 59a3fde846d2196ab1e4588eb396012ba6860712..ccae41bed757bf3d9518cd4afe4565f043b45166 100644
--- a/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
+++ b/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
@@ -47,6 +47,50 @@ properties:
     minItems: 1
     maxItems: 4
 
+  dma-ranges: true
+
+  '#address-cells':
+    const: 2
+
+  '#size-cells':
+    const: 2
+
+  non-pixel:
+    type: object
+    description:
+      Context bank for VPU non-pixel buffers, including compressed and internal buffers.
+    properties:
+      iommus:
+        maxItems: 1
+      memory-region:
+        maxItems: 1
+    required:
+      - iommus
+      - memory-region
+    additionalProperties: false
+
+  pixel:
+    type: object
+    description:
+      Context bank for VPU pixel buffers containing uncompressed video data.
+    properties:
+      iommus:
+        maxItems: 1
+    required:
+      - iommus
+    additionalProperties: false
+
+  video-firmware:
+    type: object
+    description:
+      Context bank for the VPU firmware processing domain.
+    properties:
+      iommus:
+        maxItems: 1
+    required:
+      - iommus
+    additionalProperties: false
+
 required:
   - reg
   - clocks
@@ -55,4 +99,11 @@ required:
   - memory-region
   - power-domains
 
+oneOf:
+  - required:
+      - iommus
+  - required:
+      - non-pixel
+      - pixel
+
 additionalProperties: true

-- 
2.34.1

[PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Reference qcom,venus-common.yaml, which describes the per-stream context
bank subnodes, and drop "iommus" from the required list. The common
schema accepts either the flat "iommus" or the "non-pixel" and "pixel"
subnode pair, so device trees that have not been converted still
validate.

Update the example to the subnode form, which also picks up the two
supporting properties the subnodes need on the parent video-codec node,
'#address-cells' and '#size-cells' of 2 and an empty "dma-ranges". Both
are described in the common schema change.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 .../devicetree/bindings/media/qcom,sm8550-iris.yaml    | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
index 0400ca1bff05dcef6b742c3fbf77e38adca9f280..3d8ff5677bd4fb7f3619a95b1c5f6f9eaf39b32c 100644
--- a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
+++ b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
@@ -98,10 +98,10 @@ required:
   - interconnect-names
   - resets
   - reset-names
-  - iommus
   - dma-coherent
 
 allOf:
+  - $ref: qcom,venus-common.yaml#
   - if:
       properties:
         compatible:
@@ -177,12 +177,24 @@ examples:
         resets = <&gcc GCC_VIDEO_AXI0_CLK_ARES>;
         reset-names = "bus";
 
-        iommus = <&apps_smmu 0x1940 0x0000>,
-                 <&apps_smmu 0x1947 0x0000>;
         dma-coherent;
 
         operating-points-v2 = <&iris_opp_table>;
 
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        dma-ranges;
+
+        non-pixel {
+            iommus = <&apps_smmu 0x1940 0x0000>;
+            memory-region = <&iris_resv>;
+        };
+
+        pixel {
+            iommus = <&apps_smmu 0x1947 0x0000>;
+        };
+
         iris_opp_table: opp-table {
             compatible = "operating-points-v2";
 

-- 
2.34.1

[PATCH v2 03/12] media: iris: Add platform hooks for context bank device setup

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range. Keeping each stream inside its own range needs a
separate IOMMU domain per stream, which in turn needs a separate struct
device per stream, since the IOMMU core attaches a domain per device.

Which streams exist, and therefore which context bank devices have to be
created, differs between VPU generations. Add init_cb_devs() and
deinit_cb_devs() to struct vpu_ops so platform data can supply the right
setup, and call them from probe and remove. Both hooks are optional, so
platforms that do not implement them keep the existing behaviour of
performing DMA through the parent device.

Set the context banks up before v4l2_device_register() so the DMA
plumbing is in place before any video device is visible to userspace,
and tear them down on the probe error path and in iris_remove().

No functional change yet, as no platform implements the hooks.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_probe.c      | 25 +++++++++++++++++++++-
 drivers/media/platform/qcom/iris/iris_vpu_common.h |  2 ++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
index c2dcb50a27824d45d5fbc8b9e22591decbe2a23b..2594f5a67378af9a547f23dec2d2c057506dda65 100644
--- a/drivers/media/platform/qcom/iris/iris_probe.c
+++ b/drivers/media/platform/qcom/iris/iris_probe.c
@@ -15,6 +15,7 @@
 #include "iris_core.h"
 #include "iris_ctrls.h"
 #include "iris_vidc.h"
+#include "iris_vpu_common.h"
 
 static int iris_init_icc(struct iris_core *core)
 {
@@ -150,6 +151,20 @@ static int iris_init_resources(struct iris_core *core)
 	return iris_init_resets(core);
 }
 
+static int iris_init_cb_devs(struct iris_core *core)
+{
+	if (core->iris_platform_data->vpu_ops->init_cb_devs)
+		return core->iris_platform_data->vpu_ops->init_cb_devs(core);
+
+	return 0;
+}
+
+static void iris_deinit_cb_devs(struct iris_core *core)
+{
+	if (core->iris_platform_data->vpu_ops->deinit_cb_devs)
+		core->iris_platform_data->vpu_ops->deinit_cb_devs(core);
+}
+
 static int iris_register_video_device(struct iris_core *core, enum domain_type type)
 {
 	struct video_device *vdev;
@@ -207,6 +222,8 @@ static void iris_remove(struct platform_device *pdev)
 
 	v4l2_device_unregister(&core->v4l2_dev);
 
+	iris_deinit_cb_devs(core);
+
 	mutex_destroy(&core->lock);
 }
 
@@ -273,10 +290,14 @@ static int iris_probe(struct platform_device *pdev)
 
 	iris_session_init_caps(core);
 
-	ret = v4l2_device_register(dev, &core->v4l2_dev);
+	ret = iris_init_cb_devs(core);
 	if (ret)
 		return ret;
 
+	ret = v4l2_device_register(dev, &core->v4l2_dev);
+	if (ret)
+		goto err_cb_deinit;
+
 	ret = iris_register_video_device(core, DECODER);
 	if (ret)
 		goto err_v4l2_unreg;
@@ -310,6 +331,8 @@ static int iris_probe(struct platform_device *pdev)
 	video_unregister_device(core->vdev_dec);
 err_v4l2_unreg:
 	v4l2_device_unregister(&core->v4l2_dev);
+err_cb_deinit:
+	iris_deinit_cb_devs(core);
 
 	return ret;
 }
diff --git a/drivers/media/platform/qcom/iris/iris_vpu_common.h b/drivers/media/platform/qcom/iris/iris_vpu_common.h
index 09799a375c1426d808ab5ea4fdfcac3a203e15b3..a8df9af0d3da407b59d2d2c5f2b8a08c75e93192 100644
--- a/drivers/media/platform/qcom/iris/iris_vpu_common.h
+++ b/drivers/media/platform/qcom/iris/iris_vpu_common.h
@@ -22,6 +22,8 @@ struct vpu_ops {
 	void (*program_bootup_registers)(struct iris_core *core);
 	u64 (*calc_freq)(struct iris_inst *inst, size_t data_size);
 	int (*set_hwmode)(struct iris_core *core);
+	int (*init_cb_devs)(struct iris_core *core);
+	void (*deinit_cb_devs)(struct iris_core *core);
 };
 
 int iris_vpu_boot_firmware(struct iris_core *core);

-- 
2.34.1

[PATCH v2 04/12] media: iris: Add helper to create a context bank device

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range. A stream can only be confined to its range if it
has an IOMMU domain of its own, and the IOMMU core attaches a domain per
struct device, so each stream needs its own device.
Add iris_create_cb_dev(), which looks up a named child of the iris node
and registers it as a platform device parented to the iris core. The
child's fwnode is handed to platform_device_register_full() so the OF
core applies that subnode's "iommus" property and the new device gets
its own IOMMU domain. The DMA mask comes from platform data, and the
segment size and boundary are capped at 32 bits to match the addressing
the VPU performs.
Return NULL when the named child is absent, so callers can treat a
device tree without context bank subnodes as a supported configuration
rather than an error.
Backports are intended since the first DTS of 8550 binding schema.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_resources.c | 28 +++++++++++++++++++++++
 drivers/media/platform/qcom/iris/iris_resources.h |  1 +
 2 files changed, 29 insertions(+)

diff --git a/drivers/media/platform/qcom/iris/iris_resources.c b/drivers/media/platform/qcom/iris/iris_resources.c
index 872bd09656b151eb9ed5eda2f9774d3095d3aeeb..9e02a92baae75803c2c12a2ca994006987c69596 100644
--- a/drivers/media/platform/qcom/iris/iris_resources.c
+++ b/drivers/media/platform/qcom/iris/iris_resources.c
@@ -5,6 +5,7 @@
 
 #include <linux/clk.h>
 #include <linux/devfreq.h>
+#include <linux/dma-mapping.h>
 #include <linux/interconnect.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_opp.h>
@@ -137,3 +138,30 @@ int iris_disable_unprepare_clock(struct iris_core *core, enum platform_clk_type
 
 	return 0;
 }
+
+struct device *iris_create_cb_dev(struct iris_core *core, const char *name)
+{
+	struct platform_device_info plat_dev_info = {};
+	struct device_node *child_of_node;
+	struct platform_device *pdev;
+
+	child_of_node = of_get_child_by_name(core->dev->of_node, name);
+	if (!child_of_node)
+		return NULL;
+
+	plat_dev_info.dma_mask = core->iris_platform_data->dma_mask;
+	plat_dev_info.fwnode = &child_of_node->fwnode;
+	plat_dev_info.name = child_of_node->name;
+	plat_dev_info.id = PLATFORM_DEVID_AUTO;
+	plat_dev_info.parent = core->dev;
+
+	pdev = platform_device_register_full(&plat_dev_info);
+	of_node_put(child_of_node);
+	if (IS_ERR(pdev))
+		return ERR_CAST(pdev);
+
+	dma_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));
+	dma_set_seg_boundary(&pdev->dev, DMA_BIT_MASK(32));
+
+	return &pdev->dev;
+}
diff --git a/drivers/media/platform/qcom/iris/iris_resources.h b/drivers/media/platform/qcom/iris/iris_resources.h
index 6bfbd2dc6db095ec05e53c894e048285f82446c6..ca53c01f60aef2040002f526b8f1b6a9094d1518 100644
--- a/drivers/media/platform/qcom/iris/iris_resources.h
+++ b/drivers/media/platform/qcom/iris/iris_resources.h
@@ -15,5 +15,6 @@ int iris_unset_icc_bw(struct iris_core *core);
 int iris_set_icc_bw(struct iris_core *core, unsigned long icc_bw);
 int iris_disable_unprepare_clock(struct iris_core *core, enum platform_clk_type clk_type);
 int iris_prepare_enable_clock(struct iris_core *core, enum platform_clk_type clk_type);
+struct device *iris_create_cb_dev(struct iris_core *core, const char *name);
 
 #endif

-- 
2.34.1

[PATCH v2 05/12] media: iris: Route buffers to the matching context bank device

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range. With a context bank device per stream, every
allocation has to be made against the device whose IOMMU domain can
address it: allocating a non-pixel buffer against the pixel device, or
against the parent, places it in a domain that carries no restriction and
the VPU faults when it later accesses that address.

Add iris_get_cb_dev(), which maps a buffer type to the owning context
bank device. Bitstream and internal buffers (BIN, ARP, COMV, LINE,
NON_COMV, PERSIST) belong to the non-pixel device, and uncompressed
buffers (DPB, PARTIAL, SCRATCH_1, SCRATCH_2, VPSS) to the pixel device.
BUF_INPUT and BUF_OUTPUT depend on direction and are resolved from
inst->domain: for a decoder the input is non-pixel and the output pixel,
and the other way round for an encoder.

Use it for internal buffer alloc and free, for the vb2 queue devices, and
for the HFI queue and SFR allocations, which are non-pixel.

Fall back to core->dev whenever the relevant context bank device is
absent, so platforms still describing "iommus" on the parent iris node
behave exactly as before and can be converted one at a time.

Backports are intended since the first DTS of 8550 binding schema.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_buffer.c    |  8 ++---
 drivers/media/platform/qcom/iris/iris_core.h      |  4 +++
 drivers/media/platform/qcom/iris/iris_hfi_queue.c | 16 +++++----
 drivers/media/platform/qcom/iris/iris_resources.c | 41 +++++++++++++++++++++++
 drivers/media/platform/qcom/iris/iris_resources.h |  1 +
 drivers/media/platform/qcom/iris/iris_vidc.c      |  4 +--
 6 files changed, 61 insertions(+), 13 deletions(-)

diff --git a/drivers/media/platform/qcom/iris/iris_buffer.c b/drivers/media/platform/qcom/iris/iris_buffer.c
index 246ad0abbac3510113e1f760406c81b1461377a3..249c9f1d0d5dadb391f269e9aee5181fe408cd3b 100644
--- a/drivers/media/platform/qcom/iris/iris_buffer.c
+++ b/drivers/media/platform/qcom/iris/iris_buffer.c
@@ -529,7 +529,7 @@ static int iris_create_internal_buffer(struct iris_inst *inst,
 				       enum iris_buffer_type buffer_type, u32 index)
 {
 	struct iris_buffers *buffers = &inst->buffers[buffer_type];
-	struct iris_core *core = inst->core;
+	struct device *dev = iris_get_cb_dev(inst, buffer_type);
 	struct iris_buffer *buffer;
 
 	if (!buffers->size)
@@ -545,7 +545,7 @@ static int iris_create_internal_buffer(struct iris_inst *inst,
 	buffer->buffer_size = buffers->size;
 	buffer->dma_attrs = DMA_ATTR_WRITE_COMBINE | DMA_ATTR_NO_KERNEL_MAPPING;
 
-	buffer->kvaddr = dma_alloc_attrs(core->dev, buffer->buffer_size,
+	buffer->kvaddr = dma_alloc_attrs(dev, buffer->buffer_size,
 					 &buffer->device_addr, GFP_KERNEL, buffer->dma_attrs);
 	if (!buffer->kvaddr) {
 		kfree(buffer);
@@ -682,10 +682,10 @@ int iris_queue_internal_buffers(struct iris_inst *inst, u32 plane)
 
 int iris_destroy_internal_buffer(struct iris_inst *inst, struct iris_buffer *buffer)
 {
-	struct iris_core *core = inst->core;
+	struct device *dev = iris_get_cb_dev(inst, buffer->type);
 
 	list_del(&buffer->list);
-	dma_free_attrs(core->dev, buffer->buffer_size, buffer->kvaddr,
+	dma_free_attrs(dev, buffer->buffer_size, buffer->kvaddr,
 		       buffer->device_addr, buffer->dma_attrs);
 	kfree(buffer);
 
diff --git a/drivers/media/platform/qcom/iris/iris_core.h b/drivers/media/platform/qcom/iris/iris_core.h
index 24da60448cf24820af7947b85eb7208555ab7786..3c96f46cf567b2802148b2a7cedb8488b6b9468b 100644
--- a/drivers/media/platform/qcom/iris/iris_core.h
+++ b/drivers/media/platform/qcom/iris/iris_core.h
@@ -36,6 +36,8 @@ struct qcom_ubwc_cfg_data;
  * struct iris_core - holds core parameters valid for all instances
  *
  * @dev: reference to device structure
+ * @np_dev: reference to non-pixel device structure
+ * @p_dev: reference to pixel device structure
  * @reg_base: IO memory base address
  * @irq: iris irq
  * @v4l2_dev: a holder for v4l2 device structure
@@ -81,6 +83,8 @@ struct qcom_ubwc_cfg_data;
 
 struct iris_core {
 	struct device				*dev;
+	struct device				*np_dev;
+	struct device				*p_dev;
 	void __iomem				*reg_base;
 	int					irq;
 	struct v4l2_device			v4l2_dev;
diff --git a/drivers/media/platform/qcom/iris/iris_hfi_queue.c b/drivers/media/platform/qcom/iris/iris_hfi_queue.c
index bf6db23b53e2106c08f2139b643f8626af8bc40a..ce6a682b0f9ada79f9fae26289db298855d777c2 100644
--- a/drivers/media/platform/qcom/iris/iris_hfi_queue.c
+++ b/drivers/media/platform/qcom/iris/iris_hfi_queue.c
@@ -245,25 +245,26 @@ static void iris_hfi_queue_deinit(struct iris_iface_q_info *iface_q)
 
 int iris_hfi_queues_init(struct iris_core *core)
 {
+	struct device *dev = core->np_dev ? core->np_dev : core->dev;
 	struct iris_hfi_queue_table_header *q_tbl_hdr;
 	u32 queue_size;
 
 	/* Iris hardware requires 4K queue alignment */
 	queue_size = ALIGN((sizeof(*q_tbl_hdr) + (IFACEQ_QUEUE_SIZE * IFACEQ_NUMQ)), SZ_4K);
-	core->iface_q_table_vaddr = dma_alloc_attrs(core->dev, queue_size,
+	core->iface_q_table_vaddr = dma_alloc_attrs(dev, queue_size,
 						    &core->iface_q_table_daddr,
 						    GFP_KERNEL, DMA_ATTR_WRITE_COMBINE);
 	if (!core->iface_q_table_vaddr) {
-		dev_err(core->dev, "queues alloc and map failed\n");
+		dev_err(dev, "queues alloc and map failed\n");
 		return -ENOMEM;
 	}
 
-	core->sfr_vaddr = dma_alloc_attrs(core->dev, SFR_SIZE,
+	core->sfr_vaddr = dma_alloc_attrs(dev, SFR_SIZE,
 					  &core->sfr_daddr,
 					  GFP_KERNEL, DMA_ATTR_WRITE_COMBINE);
 	if (!core->sfr_vaddr) {
-		dev_err(core->dev, "sfr alloc and map failed\n");
-		dma_free_attrs(core->dev, queue_size, core->iface_q_table_vaddr,
+		dev_err(dev, "sfr alloc and map failed\n");
+		dma_free_attrs(dev, queue_size, core->iface_q_table_vaddr,
 			       core->iface_q_table_daddr, DMA_ATTR_WRITE_COMBINE);
 		return -ENOMEM;
 	}
@@ -291,6 +292,7 @@ int iris_hfi_queues_init(struct iris_core *core)
 
 void iris_hfi_queues_deinit(struct iris_core *core)
 {
+	struct device *dev = core->np_dev ? core->np_dev : core->dev;
 	u32 queue_size;
 
 	if (!core->iface_q_table_vaddr)
@@ -300,7 +302,7 @@ void iris_hfi_queues_deinit(struct iris_core *core)
 	iris_hfi_queue_deinit(&core->message_queue);
 	iris_hfi_queue_deinit(&core->command_queue);
 
-	dma_free_attrs(core->dev, SFR_SIZE, core->sfr_vaddr,
+	dma_free_attrs(dev, SFR_SIZE, core->sfr_vaddr,
 		       core->sfr_daddr, DMA_ATTR_WRITE_COMBINE);
 
 	core->sfr_vaddr = NULL;
@@ -309,7 +311,7 @@ void iris_hfi_queues_deinit(struct iris_core *core)
 	queue_size = ALIGN(sizeof(struct iris_hfi_queue_table_header) +
 		(IFACEQ_QUEUE_SIZE * IFACEQ_NUMQ), SZ_4K);
 
-	dma_free_attrs(core->dev, queue_size, core->iface_q_table_vaddr,
+	dma_free_attrs(dev, queue_size, core->iface_q_table_vaddr,
 		       core->iface_q_table_daddr, DMA_ATTR_WRITE_COMBINE);
 
 	core->iface_q_table_vaddr = NULL;
diff --git a/drivers/media/platform/qcom/iris/iris_resources.c b/drivers/media/platform/qcom/iris/iris_resources.c
index 9e02a92baae75803c2c12a2ca994006987c69596..fbbe529c74216cd476f06c6d0a5dd6f72b98d3e6 100644
--- a/drivers/media/platform/qcom/iris/iris_resources.c
+++ b/drivers/media/platform/qcom/iris/iris_resources.c
@@ -13,6 +13,7 @@
 #include <linux/reset.h>
 
 #include "iris_core.h"
+#include "iris_instance.h"
 #include "iris_resources.h"
 
 #define BW_THRESHOLD 50000
@@ -165,3 +166,43 @@ struct device *iris_create_cb_dev(struct iris_core *core, const char *name)
 
 	return &pdev->dev;
 }
+
+struct device *iris_get_cb_dev(struct iris_inst *inst, enum iris_buffer_type buffer_type)
+{
+	struct iris_core *core = inst->core;
+	struct device *dev = NULL;
+
+	switch (buffer_type) {
+	case BUF_INPUT:
+		if (inst->domain == DECODER)
+			dev = core->np_dev;
+		else
+			dev = core->p_dev;
+		break;
+	case BUF_OUTPUT:
+		if (inst->domain == DECODER)
+			dev = core->p_dev;
+		else
+			dev = core->np_dev;
+		break;
+	case BUF_DPB:
+	case BUF_PARTIAL:
+	case BUF_SCRATCH_1:
+	case BUF_SCRATCH_2:
+	case BUF_VPSS:
+		dev = core->p_dev;
+		break;
+	case BUF_BIN:
+	case BUF_ARP:
+	case BUF_COMV:
+	case BUF_LINE:
+	case BUF_NON_COMV:
+	case BUF_PERSIST:
+		dev = core->np_dev;
+		break;
+	default:
+		dev_err(core->dev, "invalid buffer type: %d\n", buffer_type);
+	}
+
+	return dev ? dev : core->dev;
+}
diff --git a/drivers/media/platform/qcom/iris/iris_resources.h b/drivers/media/platform/qcom/iris/iris_resources.h
index ca53c01f60aef2040002f526b8f1b6a9094d1518..2eef0676a146f1836fc7445a715e43185c645099 100644
--- a/drivers/media/platform/qcom/iris/iris_resources.h
+++ b/drivers/media/platform/qcom/iris/iris_resources.h
@@ -16,5 +16,6 @@ int iris_set_icc_bw(struct iris_core *core, unsigned long icc_bw);
 int iris_disable_unprepare_clock(struct iris_core *core, enum platform_clk_type clk_type);
 int iris_prepare_enable_clock(struct iris_core *core, enum platform_clk_type clk_type);
 struct device *iris_create_cb_dev(struct iris_core *core, const char *name);
+struct device *iris_get_cb_dev(struct iris_inst *inst, enum iris_buffer_type buffer_type);
 
 #endif
diff --git a/drivers/media/platform/qcom/iris/iris_vidc.c b/drivers/media/platform/qcom/iris/iris_vidc.c
index 14d63dc76c9bacbed3533147cd5325410f9c94bd..26df872fb4fa1cc6b2aacebb7453256864b1462a 100644
--- a/drivers/media/platform/qcom/iris/iris_vidc.c
+++ b/drivers/media/platform/qcom/iris/iris_vidc.c
@@ -107,7 +107,7 @@ iris_m2m_queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_
 	src_vq->drv_priv = inst;
 	src_vq->buf_struct_size = sizeof(struct iris_buffer);
 	src_vq->min_reqbufs_allocation = MIN_BUFFERS;
-	src_vq->dev = inst->core->dev;
+	src_vq->dev = iris_get_cb_dev(inst, BUF_INPUT);
 	src_vq->lock = &inst->ctx_q_lock;
 	ret = vb2_queue_init(src_vq);
 	if (ret)
@@ -121,7 +121,7 @@ iris_m2m_queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_
 	dst_vq->drv_priv = inst;
 	dst_vq->buf_struct_size = sizeof(struct iris_buffer);
 	dst_vq->min_reqbufs_allocation = MIN_BUFFERS;
-	dst_vq->dev = inst->core->dev;
+	dst_vq->dev = iris_get_cb_dev(inst, BUF_OUTPUT);
 	dst_vq->lock = &inst->ctx_q_lock;
 
 	return vb2_queue_init(dst_vq);

-- 
2.34.1

[PATCH v2 06/12] media: iris: Skip DMA mask setup when the core device has no IOMMU

[Vikash Garodia]

Once the streams are described as context bank subnodes, the "iommus"
property no longer sits on the parent iris node. That device then has no
IOMMU domain of its own and never performs DMA directly, so calling
dma_set_mask_and_coherent() on it is meaningless, and on a device with no
IOMMU it can fail and abort probe.

Set the DMA mask only when device_iommu_mapped() reports an IOMMU on the
core device. Platforms that have not been converted still carry "iommus"
on the parent node and keep the existing setup. For converted platforms
the mask is applied to each context bank device instead, in
iris_create_cb_dev().

Backports are intended since the first DTS of 8550 binding schema.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_probe.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
index 2594f5a67378af9a547f23dec2d2c057506dda65..c40c4ec44e83e4aa212b58a19b64d46a3d9f16ce 100644
--- a/drivers/media/platform/qcom/iris/iris_probe.c
+++ b/drivers/media/platform/qcom/iris/iris_probe.c
@@ -310,9 +310,11 @@ static int iris_probe(struct platform_device *pdev)
 
 	dma_mask = core->iris_platform_data->dma_mask;
 
-	ret = dma_set_mask_and_coherent(dev, dma_mask);
-	if (ret)
-		goto err_vdev_unreg_enc;
+	if (device_iommu_mapped(dev)) {
+		ret = dma_set_mask_and_coherent(dev, dma_mask);
+		if (ret)
+			goto err_vdev_unreg_enc;
+	}
 
 	dma_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));
 	dma_set_seg_boundary(&pdev->dev, DMA_BIT_MASK(32));

-- 
2.34.1

[PATCH v2 07/12] media: iris: Create pixel and non-pixel context banks on VPU3x

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range.

Implement the context bank hooks for VPU3x. iris_vpu3x_init_cb_devs()
creates the "non-pixel" and "pixel" devices from the matching device tree
subnodes, and iris_vpu3x_deinit_cb_devs() unregisters them. If creating
the pixel device fails, the non-pixel device is unregistered and its
pointer cleared before the error is returned.

Wire the hooks into iris_vpu3_ops and iris_vpu33_ops, which cover the
platforms whose device trees are converted to context bank subnodes.
iris_vpu35_ops is left unchanged, as sm8750 still describes its streams
with "iommus" on the parent node, and the fallback in iris_get_cb_dev()
keeps it working until its device tree is converted.

Backports are intended since the first DTS of 8550 binding schema.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_vpu3x.c | 38 +++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/media/platform/qcom/iris/iris_vpu3x.c b/drivers/media/platform/qcom/iris/iris_vpu3x.c
index 3dad47be78b58f6cd5ed6f333b3376571a04dbf0..623a0f8a7982c0b5c2e3741a34c1367e9aaf4e27 100644
--- a/drivers/media/platform/qcom/iris/iris_vpu3x.c
+++ b/drivers/media/platform/qcom/iris/iris_vpu3x.c
@@ -254,6 +254,40 @@ static void iris_vpu35_power_off_hw(struct iris_core *core)
 	iris_disable_unprepare_clock(core, IRIS_AXI_CLK);
 }
 
+static int iris_vpu3x_init_cb_devs(struct iris_core *core)
+{
+	struct device *dev;
+
+	dev = iris_create_cb_dev(core, "non-pixel");
+	if (IS_ERR(dev))
+		return PTR_ERR(dev);
+
+	core->np_dev = dev;
+
+	dev = iris_create_cb_dev(core, "pixel");
+	if (IS_ERR(dev))
+		goto unreg_np_dev;
+
+	core->p_dev = dev;
+
+	return 0;
+
+unreg_np_dev:
+	if (core->np_dev)
+		platform_device_unregister(to_platform_device(core->np_dev));
+	core->np_dev = NULL;
+
+	return PTR_ERR(dev);
+}
+
+static void iris_vpu3x_deinit_cb_devs(struct iris_core *core)
+{
+	if (core->p_dev)
+		platform_device_unregister(to_platform_device(core->p_dev));
+	if (core->np_dev)
+		platform_device_unregister(to_platform_device(core->np_dev));
+}
+
 const struct vpu_ops iris_vpu3_ops = {
 	.power_off_hw = iris_vpu3_power_off_hardware,
 	.power_on_hw = iris_vpu_power_on_hw,
@@ -261,6 +295,8 @@ const struct vpu_ops iris_vpu3_ops = {
 	.power_on_controller = iris_vpu_power_on_controller,
 	.calc_freq = iris_vpu3x_vpu4x_calculate_frequency,
 	.set_hwmode = iris_vpu_set_hwmode,
+	.init_cb_devs = iris_vpu3x_init_cb_devs,
+	.deinit_cb_devs = iris_vpu3x_deinit_cb_devs,
 };
 
 const struct vpu_ops iris_vpu33_ops = {
@@ -270,6 +306,8 @@ const struct vpu_ops iris_vpu33_ops = {
 	.power_on_controller = iris_vpu_power_on_controller,
 	.calc_freq = iris_vpu3x_vpu4x_calculate_frequency,
 	.set_hwmode = iris_vpu_set_hwmode,
+	.init_cb_devs = iris_vpu3x_init_cb_devs,
+	.deinit_cb_devs = iris_vpu3x_deinit_cb_devs,
 };
 
 const struct vpu_ops iris_vpu35_ops = {

-- 
2.34.1

[PATCH v2 08/12] arm64: dts: qcom: hamoa: Add Iris context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe the two streams as "non-pixel" and "pixel" subnodes so each gets
its own IOMMU domain, with stream 0x1940 becoming non-pixel and 0x1947
becoming pixel. Point the non-pixel subnode at a reserved-memory node
whose "iommu-addresses" covers [0, 0x25800000), which excludes the low
600 MB from that domain's IOVA allocator and keeps its allocations above
the boundary the stream can address. The reservation node carries no
"reg", so it is a pure IOVA carve-out rather than a memory mapping. The
pixel stream is left free to use the whole range.

The video-codec node also gains '#address-cells' and '#size-cells' of 2,
which set the cell widths used to parse the "iommu-addresses" entry that
refers to the non-pixel subnode, and an empty "dma-ranges" declaring the
1:1 DMA translation into the parent. Both are described in the common
schema change.

Fixes: 9065340ac04d ("arm64: dts: qcom: x1e80100: Add IRIS video codec")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/hamoa.dtsi | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/hamoa.dtsi b/arch/arm64/boot/dts/qcom/hamoa.dtsi
index 09527dcf957672b4b9658988359e79d8a432fd93..37f4449aa91e605a2112f399604df0cc6c64162b 100644
--- a/arch/arm64/boot/dts/qcom/hamoa.dtsi
+++ b/arch/arm64/boot/dts/qcom/hamoa.dtsi
@@ -658,6 +658,10 @@ smem_mem: smem@ffe00000 {
 			hwlocks = <&tcsr_mutex 3>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	qup_opp_table_100mhz: opp-table-qup100mhz {
@@ -5436,10 +5440,12 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			resets = <&gcc GCC_VIDEO_AXI0_CLK_ARES>;
 			reset-names = "bus";
 
-			iommus = <&apps_smmu 0x1940 0>,
-				 <&apps_smmu 0x1947 0>;
 			dma-coherent;
 
+			#address-cells = <2>;
+			#size-cells = <2>;
+			dma-ranges;
+
 			/*
 			 * IRIS firmware is signed by vendors, only
 			 * enable on boards where the proper signed firmware
@@ -5447,6 +5453,15 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			 */
 			status = "disabled";
 
+			iris_non_pixel: non-pixel {
+				iommus = <&apps_smmu 0x1940 0x0>;
+				memory-region = <&iris_resv>;
+			};
+
+			iris_pixel: pixel {
+				iommus = <&apps_smmu 0x1947 0x0>;
+			};
+
 			iris_opp_table: opp-table {
 				compatible = "operating-points-v2";
 

-- 
2.34.1

[PATCH v2 09/12] arm64: dts: qcom: sm8550: Add Iris context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe the two streams as "non-pixel" and "pixel" subnodes so each gets
its own IOMMU domain, with stream 0x1940 becoming non-pixel and 0x1947
becoming pixel. Point the non-pixel subnode at a reserved-memory node
whose "iommu-addresses" covers [0, 0x25800000), which excludes the low
600 MB from that domain's IOVA allocator and keeps its allocations above
the boundary the stream can address. The reservation node carries no
"reg", so it is a pure IOVA carve-out rather than a memory mapping. The
pixel stream is left free to use the whole range.

qcs8550 discards the inherited reserved-memory node with /delete-node/,
so it needs its own copy of the reservation for the non-pixel subnode
phandle to resolve.

The video-codec node also gains '#address-cells' and '#size-cells' of 2,
which set the cell widths used to parse the "iommu-addresses" entry that
refers to the non-pixel subnode, and an empty "dma-ranges" declaring the
1:1 DMA translation into the parent. Both are described in the common
schema change.

Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/qcs8550.dtsi |  4 ++++
 arch/arm64/boot/dts/qcom/sm8550.dtsi  | 19 +++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/qcs8550.dtsi b/arch/arm64/boot/dts/qcom/qcs8550.dtsi
index f0acdd0b1e9384e684a90f7f49cf63633cd70d53..db0f539bc3d0a2e83b58b3929a05f0e44d9d513f 100644
--- a/arch/arm64/boot/dts/qcom/qcs8550.dtsi
+++ b/arch/arm64/boot/dts/qcom/qcs8550.dtsi
@@ -158,5 +158,9 @@ mpss_dsm_mem: mpss-dsm-region@d4d00000 {
 			reg = <0x0 0xd4d00000 0x0 0x3300000>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 };
diff --git a/arch/arm64/boot/dts/qcom/sm8550.dtsi b/arch/arm64/boot/dts/qcom/sm8550.dtsi
index 7599b7b7e645f389f817c2694317ba12998992a5..4c8ad7f026fe536fe6dd69b015f1e79edcbb60f6 100644
--- a/arch/arm64/boot/dts/qcom/sm8550.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8550.dtsi
@@ -1087,6 +1087,10 @@ hyp_ext_reserved_mem: hyp-ext-reserved-region@ff700000 {
 			reg = <0 0xff700000 0 0x100000>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	smp2p-adsp {
@@ -3690,10 +3694,12 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			resets = <&gcc GCC_VIDEO_AXI0_CLK_ARES>;
 			reset-names = "bus";
 
-			iommus = <&apps_smmu 0x1940 0>,
-				 <&apps_smmu 0x1947 0>;
 			dma-coherent;
 
+			#address-cells = <2>;
+			#size-cells = <2>;
+			dma-ranges;
+
 			/*
 			 * IRIS firmware is signed by vendors, only
 			 * enable on boards where the proper signed firmware
@@ -3701,6 +3707,15 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			 */
 			status = "disabled";
 
+			iris_non_pixel: non-pixel {
+				iommus = <&apps_smmu 0x1940 0x0>;
+				memory-region = <&iris_resv>;
+			};
+
+			iris_pixel: pixel {
+				iommus = <&apps_smmu 0x1947 0x0>;
+			};
+
 			iris_opp_table: opp-table {
 				compatible = "operating-points-v2";
 

-- 
2.34.1

[PATCH v2 10/12] arm64: dts: qcom: lemans: Add Iris context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe the two streams as "non-pixel" and "pixel" subnodes so each gets
its own IOMMU domain, with stream 0x0880 becoming non-pixel and 0x0887
becoming pixel. Point the non-pixel subnode at a reserved-memory node
whose "iommu-addresses" covers [0, 0x25800000), which excludes the low
600 MB from that domain's IOVA allocator and keeps its allocations above
the boundary the stream can address. The reservation node carries no
"reg", so it is a pure IOVA carve-out rather than a memory mapping. The
pixel stream is left free to use the whole range.

The video-codec node also gains '#address-cells' and '#size-cells' of 2,
which set the cell widths used to parse the "iommu-addresses" entry that
refers to the non-pixel subnode, and an empty "dma-ranges" declaring the
1:1 DMA translation into the parent. Both are described in the common
schema change.

Fixes: 7bc95052c64f ("arm64: dts: qcom: sa8775p: add support for video node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/lemans.dtsi | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/lemans.dtsi b/arch/arm64/boot/dts/qcom/lemans.dtsi
index 3b0539e27b5192582e0bc9ea248f1c0382e05030..04cdaabc14881ac28edc11f7f872b3cc49f1efbd 100644
--- a/arch/arm64/boot/dts/qcom/lemans.dtsi
+++ b/arch/arm64/boot/dts/qcom/lemans.dtsi
@@ -861,6 +861,10 @@ cpucp_fw_mem: cpucp-fw@db200000 {
 			reg = <0x0 0xdb200000 0x0 0x100000>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	smp2p-adsp {
@@ -4961,12 +4965,23 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			resets = <&gcc GCC_VIDEO_AXI0_CLK_ARES>;
 			reset-names = "bus";
 
-			iommus = <&apps_smmu 0x0880 0x0400>,
-				 <&apps_smmu 0x0887 0x0400>;
 			dma-coherent;
 
+			#address-cells = <2>;
+			#size-cells = <2>;
+			dma-ranges;
+
 			status = "disabled";
 
+			iris_non_pixel: non-pixel {
+				iommus = <&apps_smmu 0x0880 0x0400>;
+				memory-region = <&iris_resv>;
+			};
+
+			iris_pixel: pixel {
+				iommus = <&apps_smmu 0x0887 0x0400>;
+			};
+
 			iris_opp_table: opp-table {
 				compatible = "operating-points-v2";
 

-- 
2.34.1

[PATCH v2 11/12] arm64: dts: qcom: monaco: Add Iris context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe the two streams as "non-pixel" and "pixel" subnodes so each gets
its own IOMMU domain, with stream 0x0880 becoming non-pixel and 0x0887
becoming pixel. Point the non-pixel subnode at a reserved-memory node
whose "iommu-addresses" covers [0, 0x25800000), which excludes the low
600 MB from that domain's IOVA allocator and keeps its allocations above
the boundary the stream can address. The reservation node carries no
"reg", so it is a pure IOVA carve-out rather than a memory mapping. The
pixel stream is left free to use the whole range.

The video-codec node also gains '#address-cells' and '#size-cells' of 2,
which set the cell widths used to parse the "iommu-addresses" entry that
refers to the non-pixel subnode, and an empty "dma-ranges" declaring the
1:1 DMA translation into the parent. Both are described in the common
schema change.

Fixes: bf6ec39c3f36 ("arm64: dts: qcom: qcs8300: add video node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/monaco.dtsi | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/monaco.dtsi b/arch/arm64/boot/dts/qcom/monaco.dtsi
index 64fc0d592282cbe303efd81491cf93708cfb75e8..ec482258d03a3b2ecc1124a3b0971f16404f6096 100644
--- a/arch/arm64/boot/dts/qcom/monaco.dtsi
+++ b/arch/arm64/boot/dts/qcom/monaco.dtsi
@@ -811,6 +811,10 @@ video_mem: video-region@9be82000 {
 			reg = <0x0 0x9be82000 0x0 0x700000>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	smp2p-adsp {
@@ -5403,12 +5407,23 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			resets = <&gcc GCC_VIDEO_AXI0_CLK_ARES>;
 			reset-names = "bus";
 
-			iommus = <&apps_smmu 0x0880 0x0400>,
-				 <&apps_smmu 0x0887 0x0400>;
 			dma-coherent;
 
+			#address-cells = <2>;
+			#size-cells = <2>;
+			dma-ranges;
+
 			status = "disabled";
 
+			iris_non_pixel: non-pixel {
+				iommus = <&apps_smmu 0x0880 0x0400>;
+				memory-region = <&iris_resv>;
+			};
+
+			iris_pixel: pixel {
+				iommus = <&apps_smmu 0x0887 0x0400>;
+			};
+
 			iris_opp_table: opp-table {
 				compatible = "operating-points-v2";
 

-- 
2.34.1

[PATCH v2 12/12] arm64: dts: qcom: sm8650: Add Iris context bank subnodes

[Vikash Garodia]

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range:
    +-----------------------------------------------------------+
    | non-pixel stream addressable range (600 MB - 3.5 GB)      |
    | 0x25800000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
    | pixel stream addressable range (0 - 3.5 GB)               |
    | 0x00000000 - 0xe0000000                                   |
    +-----------------------------------------------------------+
A single "iommus" property on the video-codec node puts every stream in
one IOMMU domain sharing one IOVA allocator, so nothing keeps a
non-pixel buffer above 600 MB. Once an allocation lands below that
boundary the hardware faults, which shows up as unhandled SMMU page
faults and spontaneous reboots:
https://gitlab.freedesktop.org/drm/msm/-/work_items/100

Describe the two streams as "non-pixel" and "pixel" subnodes so each gets
its own IOMMU domain, with stream 0x1940 becoming non-pixel and 0x1947
becoming pixel. Point the non-pixel subnode at a reserved-memory node
whose "iommu-addresses" covers [0, 0x25800000), which excludes the low
600 MB from that domain's IOVA allocator and keeps its allocations above
the boundary the stream can address. The reservation node carries no
"reg", so it is a pure IOVA carve-out rather than a memory mapping. The
pixel stream is left free to use the whole range.

The video-codec node also gains '#address-cells' and '#size-cells' of 2,
which set the cell widths used to parse the "iommu-addresses" entry that
refers to the non-pixel subnode, and an empty "dma-ranges" declaring the
1:1 DMA translation into the parent. Both are described in the common
schema change.

Fixes: 56cf5ad39a55 ("arm64: dts: qcom: sm8650: add iris DT node")
Cc: stable@vger.kernel.org
Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/sm8650.dtsi | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi
index 9ecbc0010694faf8005eabdeb033efe630f95037..6fccd8a886ec0aaa42e20b7a20333a7b77c31b48 100644
--- a/arch/arm64/boot/dts/qcom/sm8650.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi
@@ -1905,6 +1905,10 @@ llcc_lpi_mem: llcc-lpi@ff800000 {
 			reg = <0 0xff800000 0 0x600000>;
 			no-map;
 		};
+
+		iris_resv: reservation-iris {
+			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	smp2p-adsp {
@@ -5275,11 +5279,12 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 				      "xo",
 				      "core";
 
-			iommus = <&apps_smmu 0x1940 0>,
-				 <&apps_smmu 0x1947 0>;
-
 			dma-coherent;
 
+			#address-cells = <2>;
+			#size-cells = <2>;
+			dma-ranges;
+
 			/*
 			 * IRIS firmware is signed by vendors, only
 			 * enable on boards where the proper signed firmware
@@ -5287,6 +5292,15 @@ &config_noc SLAVE_VENUS_CFG QCOM_ICC_TAG_ACTIVE_ONLY>,
 			 */
 			status = "disabled";
 
+			iris_non_pixel: non-pixel {
+				iommus = <&apps_smmu 0x1940 0x0>;
+				memory-region = <&iris_resv>;
+			};
+
+			iris_pixel: pixel {
+				iommus = <&apps_smmu 0x1947 0x0>;
+			};
+
 			iris_opp_table: opp-table {
 				compatible = "operating-points-v2";
 

-- 
2.34.1

Re: [PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The schema fails to require `#address-cells`, `#size-cells`, and `dma-ranges` on the parent node when the `non-pixel` and `pixel` subnodes are used.
--

--- Patch [2]: [PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes ---
commit ba9132c7e393d239aeadc5fc3b8d92905c2ec775
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

This commit updates the sm8550-iris device tree binding to support per-stream
context bank subnodes by referencing qcom,venus-common.yaml. It drops the flat
"iommus" property from the required list and updates the example to use the new
"non-pixel" and "pixel" subnodes along with their supporting bus properties.

> diff --git a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> index 0400ca1bff05d..3d8ff5677bd4f 100644
> --- a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> @@ -98,10 +98,10 @@ required:
>    - interconnect-names
>    - resets
>    - reset-names
> -  - iommus
>    - dma-coherent
>  
>  allOf:
> +  - $ref: qcom,venus-common.yaml#

[Severity: Medium]
When referencing qcom,venus-common.yaml to support the new non-pixel and
pixel subnodes, is it possible for incomplete device trees to silently pass
validation?

In Documentation/devicetree/bindings/media/qcom,venus-common.yaml, the oneOf
check requires the non-pixel and pixel subnodes:

  - required:
      - non-pixel
      - pixel

However, it doesn't appear to enforce the presence of #address-cells,
#size-cells, and dma-ranges on the parent node when those subnodes are used.

If a device tree writer implements the new subnode configuration but forgets
to include these supporting bus properties in the parent node, could this
defective configuration pass dt_binding_check and dtbs_check, ultimately
leading to the DMA translation failures and SMMU page faults described in
the commit message?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=2

Re: [PATCH v2 01/12] dt-bindings: media: qcom,venus: Add context bank subnodes to common schema

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [High] The newly defined context bank subnodes are entirely inaccessible to the targeted `sm8550-iris` platform.
- [Medium] Missing required properties in the common schema's subnode validation block.
- [Medium] Schema validation conflict for migrated child schemas due to unconditionally required `iommus` property.
--

--- Patch [1]: [PATCH v2 01/12] dt-bindings: media: qcom,venus: Add context bank subnodes to common schema ---
commit f7ccdc698c2e9a5f1a41568fd6c456d9da607bec
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

dt-bindings: media: qcom,venus: Add context bank subnodes to common schema

This commit describes each VPU SMMU stream as its own context bank subnode
to associate it with its reachable IOVA range. It adds non-pixel, pixel,
and video-firmware to the common schema, replacing the single iommus
property approach.

> diff --git a/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml b/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
> index b21bed3148484..bfd8b1ad47312 100644
> --- a/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,sc7180-venus.yaml
[ ... ]
> @@ -91,21 +91,6 @@ properties:
>      deprecated: true
>      additionalProperties: false
>  
> -  video-firmware:
> -    type: object
> -    additionalProperties: false
> -
> -    description: |
> -      Firmware subnode is needed when the platform does not
> -      have TrustZone.
> -
> -    properties:
> -      iommus:
> -        maxItems: 1
> -
> -    required:
> -      - iommus
> -
>  required:
>    - compatible
>    - power-domain-names

[Severity: Medium]
Does the unconditionally required iommus property in this file break migrations?

Since the common schema makes iommus optional when the new subnodes are
present via a oneOf block, if a platform like sc7180 is migrated to use the
new subnode layout (dropping the parent iommus), it will fail
make dt_binding_check because qcom,sc7180-venus.yaml still unconditionally
mandates iommus in its local required list.

> diff --git a/Documentation/devicetree/bindings/media/qcom,venus-common.yaml b/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
> index 59a3fde846d21..ccae41bed757b 100644
> --- a/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
> @@ -47,6 +47,50 @@ properties:
>      minItems: 1
>      maxItems: 4
>  
> +  dma-ranges: true
> +
> +  #address-cells:
> +    const: 2
> +
> +  #size-cells:
> +    const: 2
> +
> +  non-pixel:

[Severity: High]
Are these newly defined context bank subnodes accessible to the targeted
sm8550-iris platform?

The commit message notes this limitation applies to every VPU generation and
specifically mentions fixing an issue on sm8550. However,
qcom,sm8550-iris.yaml does not appear to include a $ref to
qcom,venus-common.yaml and sets unevaluatedProperties: false.

Would adding non-pixel or pixel subnodes to the sm8550 device tree result in
an immediate validation failure because the properties are undeclared in the
iris schema?

[ ... ]
> @@ -55,4 +99,11 @@ required:
>    - memory-region
>    - power-domains
>  
> +oneOf:
> +  - required:
> +      - iommus
> +  - required:
> +      - non-pixel
> +      - pixel

[Severity: Medium]
Should #address-cells, #size-cells, and dma-ranges be enforced here when the
subnodes are used?

The commit message explains that adding the subnodes requires these supporting
properties on the parent video-codec node. Without enforcing them in this
oneOf block alongside non-pixel and pixel, device trees can omit these
properties and still pass validation.

Could this cause of_translate_dma_region() to fail or return incorrect IOVAs
at runtime if the properties are omitted?

> +
>  additionalProperties: true

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=1

Re: [PATCH v2 03/12] media: iris: Add platform hooks for context bank device setup

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 4 potential issue(s) to consider:

Pre-existing issues:
- [High] V4L2 state object `core` is allocated with `devm_kzalloc`, leading to UAF if file descriptors are kept open after device unbind.
- [High] Hardware deinitialization occurs before video devices are unregistered, allowing a race with new `open()` calls.
- [High] Video device exposed to userspace before driver data is fully initialized, causing a TOCTOU race condition.
- [High] The `sys_error_handler` delayed work is never explicitly cancelled during module removal, leading to a potential Use-After-Free.
--

--- Patch [3]: [PATCH v2 03/12] media: iris: Add platform hooks for context bank device setup ---
commit a925a8b5dc58a6c33e49594b0c98c79bb206b111
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

media: iris: Add platform hooks for context bank device setup
    
The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range. Keeping each stream inside its own range needs a
separate IOMMU domain per stream, which in turn needs a separate struct
device per stream, since the IOMMU core attaches a domain per device.

> diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
> index c2dcb50a27824..2594f5a67378a 100644
> --- a/drivers/media/platform/qcom/iris/iris_probe.c
> +++ b/drivers/media/platform/qcom/iris/iris_probe.c

[ ... ]

> @@ -150,6 +151,20 @@ static int iris_init_resources(struct iris_core *core)
>  	return iris_init_resets(core);
>  }
>  
> +static int iris_init_cb_devs(struct iris_core *core)
> +{
> +	if (core->iris_platform_data->vpu_ops->init_cb_devs)
> +		return core->iris_platform_data->vpu_ops->init_cb_devs(core);
> +
> +	return 0;
> +}
> +
> +static void iris_deinit_cb_devs(struct iris_core *core)
> +{
> +	if (core->iris_platform_data->vpu_ops->deinit_cb_devs)
> +		core->iris_platform_data->vpu_ops->deinit_cb_devs(core);
> +}
> +
>  static int iris_register_video_device(struct iris_core *core, enum domain_type type)
>  {

[Severity: High]
This isn't a bug introduced by this patch, but is it possible for userspace
to open the device before the driver data is fully initialized?

Looking at iris_register_video_device(), video_register_device() is called
before video_set_drvdata():

	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
	if (ret)
		goto err_vdev_release;

	video_set_drvdata(vdev, core);

If a rapid concurrent open() happens from userspace, iris_open() will be
invoked. It will call video_drvdata(filp) which returns NULL, and then
attempt pm_runtime_resume_and_get(core->dev), resulting in a NULL pointer
dereference.

[ ... ]

> @@ -207,6 +222,8 @@ static void iris_remove(struct platform_device *pdev)
>  
>  	v4l2_device_unregister(&core->v4l2_dev);
>  
> +	iris_deinit_cb_devs(core);
> +
>  	mutex_destroy(&core->lock);
>  }

[Severity: High]
This is a pre-existing issue, but does this teardown sequence leave a race
condition with new open() calls?

In iris_remove(), the driver unloads firmware and powers off the VPU via
iris_core_deinit(core) before video_unregister_device() is called.

If a concurrent open() happens before the video devices are unregistered,
iris_open() will call iris_core_init(core), powering the hardware back on.
Once iris_remove() finishes and returns, the device is unbound and core is
freed, but the hardware is erroneously left powered on, which can corrupt
the system state.

[Severity: High]
This is another pre-existing issue, but can the sys_error_handler delayed
work execute after the device is unbound?

The delayed work sys_error_handler is scheduled on HFI/hardware errors, but
it is never explicitly cancelled during module removal.

If a fatal hardware error triggers an interrupt just before or during
unbind, the work could be scheduled. When iris_remove() finishes, core is
freed by the devres subsystem. The delayed work will then run,
dereferencing the freed memory. Is a call to cancel_delayed_work_sync()
needed here?

[ ... ]

> @@ -273,10 +290,14 @@ static int iris_probe(struct platform_device *pdev)
>  
>  	iris_session_init_caps(core);
>  
> -	ret = v4l2_device_register(dev, &core->v4l2_dev);
> +	ret = iris_init_cb_devs(core);
>  	if (ret)
>  		return ret;
>  
> +	ret = v4l2_device_register(dev, &core->v4l2_dev);
> +	if (ret)
> +		goto err_cb_deinit;
> +

[Severity: High]
This is a pre-existing issue, but is the V4L2 state object core safely
managed if file descriptors are kept open after device unbind?

The core structure is allocated with devm_kzalloc() in iris_probe(),
meaning it will be automatically freed when the device is unbound via
sysfs.

However, if a userspace process currently holds an open file descriptor,
the character device stays alive. Calling close() or an ioctl() later will
invoke driver callbacks (like iris_close()) which dereference inst->core,
resulting in a use-after-free crash since the memory was already freed by
device resource management.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=3

Re: [PATCH v2 09/12] arm64: dts: qcom: sm8550: Add Iris context bank subnodes

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:

Pre-existing issues:
- [High] In `of_iommu_get_resv_regions()`, the code fails to advance the `maps` pointer past a node's specifier cells if the node does not match `dev->of_node`, causing the parser to fall out of sync.
- [High] If `of_translate_dma_region()` fails to translate the address, it returns `NULL`, which is assigned to `maps` without a NULL check, leading to a guaranteed kernel panic on the next loop iteration.
--

--- Patch [9]: [PATCH v2 09/12] arm64: dts: qcom: sm8550: Add Iris context bank subnodes ---
commit d594fb5947e7e4fe6f238d480eadd3c2b7770369
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

arm64: dts: qcom: sm8550: Add Iris context bank subnodes

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range. This commit separates the streams into two
subnodes, pointing the non-pixel subnode to a reserved-memory node to
exclude the lower 600 MB from its IOVA allocator.

> diff --git a/arch/arm64/boot/dts/qcom/sm8550.dtsi b/arch/arm64/boot/dts/qcom/sm8550.dtsi
> index 7599b7b7e645f..4c8ad7f026fe5 100644
> --- a/arch/arm64/boot/dts/qcom/sm8550.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8550.dtsi
> @@ -1087,6 +1087,10 @@ hyp_ext_reserved_mem: hyp-ext-reserved-region@ff700000 {
>  			reg = <0 0xff700000 0 0x100000>;
>  			no-map;
>  		};
> +
> +		iris_resv: reservation-iris {
> +			iommu-addresses = <&iris_non_pixel 0x0 0x0 0x0 0x25800000>;

[Severity: High]
This isn't a bug introduced by this patch, but adding this property exposes
a pre-existing issue in of_iommu_get_resv_regions().

If a memory-region specifies an iommu-addresses list with multiple devices,
the parsing breaks for all entries after the first one because the code fails
to advance the maps pointer past a node's specifier cells if the node does
not match dev->of_node:

drivers/iommu/of_iommu.c:of_iommu_get_resv_regions() {
    ...
			if (np == dev->of_node) {
				int prot = IOMMU_READ | IOMMU_WRITE;
    ...
			}
    ...
}

There is no else branch to compute the specifier size and advance the maps
pointer over it. The next iteration incorrectly reads the first cell of the
specifier as the next phandle, throwing the parser out of sync.

Will this be an issue if additional devices are added to this list in the
future?

[Severity: High]
This is a pre-existing issue, but adding this property could trigger a kernel
panic if the device tree is ever misconfigured.

If of_translate_dma_region() fails to translate the address (for example,
due to a missing dma-ranges property), it returns NULL. This NULL is directly
assigned to maps without a check:

drivers/iommu/of_iommu.c:of_iommu_get_resv_regions() {
    ...
				maps = of_translate_dma_region(np, maps, &iova, &length);
    ...
}

Because length is uninitialized, the loop eventually proceeds to the next
iteration where the condition while (maps < end) evaluates to true since maps
is NULL. Dereferencing maps with be32_to_cpup(maps++) then causes a kernel
panic.

Should we add a NULL check in of_iommu_get_resv_regions() to prevent this?

> +		};
>  	};

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=9

Re: [PATCH v2 07/12] media: iris: Create pixel and non-pixel context banks on VPU3x

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [High] Unregistered and freed platform devices (p_dev, np_dev) can be used by concurrent ioctls during driver removal, leading to Use-After-Free.
- [High] Context bank platform devices are missing DMA configuration, causing fatal SMMU faults.

Pre-existing issues:
- [High] Missing cancellation of delayed work sys_error_handler causes Use-After-Free on module removal.
--

--- Patch [7]: [PATCH v2 07/12] media: iris: Create pixel and non-pixel context banks on VPU3x ---
commit 6bf8596f13d0c7afe5ee94339e572204b2a9c6df
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

media: iris: Create pixel and non-pixel context banks on VPU3x

This commit implements context bank hooks for VPU3x to create "non-pixel"
and "pixel" devices from matching device tree subnodes. It wires these hooks
into the ops for relevant platforms and handles device registration and
unregistration.

> diff --git a/drivers/media/platform/qcom/iris/iris_vpu3x.c b/drivers/media/platform/qcom/iris/iris_vpu3x.c
> index 3dad47be78b58..623a0f8a7982c 100644
> --- a/drivers/media/platform/qcom/iris/iris_vpu3x.c
> +++ b/drivers/media/platform/qcom/iris/iris_vpu3x.c

[ ... ]

> @@ -254,6 +254,40 @@ static void iris_vpu35_power_off_hw(struct iris_core *core)

[ ... ]

> +static int iris_vpu3x_init_cb_devs(struct iris_core *core)
> +{
> +	struct device *dev;
> +
> +	dev = iris_create_cb_dev(core, "non-pixel");

[Severity: High]
Does this new device need explicit DMA configuration?

Since iris_create_cb_dev() creates dummy platform devices for the IOMMU
context banks without a driver, the kernel driver core never calls
really_probe() and never invokes platform_dma_configure(). Without an
explicit call to of_dma_configure() in the driver, the device lacks an IOMMU
domain.

When iris_get_cb_dev() returns these devices for buffer allocation, will the
DMA API return raw physical addresses instead of IOVA, triggering an IOMMU
context fault when the VPU's enabled SMMU streams access this memory?

> +	if (IS_ERR(dev))
> +		return PTR_ERR(dev);
> +
> +	core->np_dev = dev;
> +
> +	dev = iris_create_cb_dev(core, "pixel");
> +	if (IS_ERR(dev))
> +		goto unreg_np_dev;
> +
> +	core->p_dev = dev;
> +
> +	return 0;
> +
> +unreg_np_dev:
> +	if (core->np_dev)
> +		platform_device_unregister(to_platform_device(core->np_dev));
> +	core->np_dev = NULL;
> +
> +	return PTR_ERR(dev);
> +}
> +
> +static void iris_vpu3x_deinit_cb_devs(struct iris_core *core)
> +{
> +	if (core->p_dev)
> +		platform_device_unregister(to_platform_device(core->p_dev));
> +	if (core->np_dev)
> +		platform_device_unregister(to_platform_device(core->np_dev));

[Severity: High]
Can concurrent ioctls access these devices after they are unregistered?

If iris_remove() is called while userspace holds a file descriptor open and
executes an ioctl (like VIDIOC_QBUF), this function unregisters and frees
p_dev and np_dev. The pointers in core are not cleared, and there doesn't
appear to be synchronization with active file handles.

Could a concurrent ioctl call iris_get_cb_dev(), retrieve the freed p_dev or
np_dev pointer, and pass it to the DMA API, resulting in a use-after-free of
the device structure?

> +}

[Severity: High]
This isn't a bug introduced by this patch, but does the module removal path
leave delayed work running?

Looking at the removal path, iris_remove() destroys the lock and exits without
cancelling the sys_error_handler delayed work:

drivers/media/platform/qcom/iris/iris_probe.c:iris_remove() {
    ...
    mutex_destroy(&core->lock);
}

If a hardware error schedules core->sys_error_handler with a delay, and
iris_remove() executes immediately after, the devres manager frees the core
structure. When the delayed work executes, it will call
iris_sys_error_handler(), attempting to access the freed core memory.

Should cancel_delayed_work_sync() be called during removal to prevent a
use-after-free of the core structure?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=7

Re: [PATCH v2 06/12] media: iris: Skip DMA mask setup when the core device has no IOMMU

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:

New issues:
- [High] Silent DMA allocation fallback causing hardware breakage on updated device trees.

Pre-existing issues:
- [High] Race condition exposing uninitialized device leading to NULL pointer dereference or DMA misconfiguration.
--

--- Patch [6]: [PATCH v2 06/12] media: iris: Skip DMA mask setup when the core device has no IOMMU ---
commit 91265093c9bc3bb22f1e175614f1dde24649bf5b
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

media: iris: Skip DMA mask setup when the core device has no IOMMU

This commit skips calling dma_set_mask_and_coherent() on the parent iris
device if it has no IOMMU mapped. It sets the DMA mask only when
device_iommu_mapped() reports an IOMMU on the core device, preventing
probe failures on newer platforms where "iommus" is on context bank subnodes.

Cc: stable@vger.kernel.org

> diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
> index 2594f5a67378a..c40c4ec44e83e 100644
> --- a/drivers/media/platform/qcom/iris/iris_probe.c
> +++ b/drivers/media/platform/qcom/iris/iris_probe.c
> @@ -310,9 +310,11 @@ static int iris_probe(struct platform_device *pdev)
>  
>  	dma_mask = core->iris_platform_data->dma_mask;
>  
> -	ret = dma_set_mask_and_coherent(dev, dma_mask);
> -	if (ret)
> -		goto err_vdev_unreg_enc;
> +	if (device_iommu_mapped(dev)) {
> +		ret = dma_set_mask_and_coherent(dev, dma_mask);
> +		if (ret)
> +			goto err_vdev_unreg_enc;
> +	}

[Severity: High]
Does this change introduce a silent DMA allocation fallback that could
cause SMMU faults or memory corruption at runtime?

If the new device tree bindings are used (where the "iommus" property is
moved to context bank subnodes), device_iommu_mapped(dev) returns false
and probe skips dma_set_mask_and_coherent().

However, if no platform actually implements the .init_cb_devs hook,
iris_init_cb_devs() will silently return success without creating the
context bank subdevices:

drivers/media/platform/qcom/iris/iris_probe.c:iris_init_cb_devs() {
	if (core->iris_platform_data->vpu_ops->init_cb_devs)
		return core->iris_platform_data->vpu_ops->init_cb_devs(core);

	return 0;
}

When DMA allocations occur, iris_get_cb_dev() falls back to the parent
core device which now has no IOMMU and an unconfigured DMA mask:

drivers/media/platform/qcom/iris/iris_resources.c:iris_get_cb_dev() {
	...
	return dev ? dev : core->dev;
}

[Severity: High]
This isn't a bug introduced by this patch, but there is a race condition
where device nodes are exposed to userspace before critical hardware setup
like DMA masks and PM runtime initialization occurs.

Earlier in iris_probe(), the video devices are registered:

drivers/media/platform/qcom/iris/iris_probe.c:iris_probe() {
	...
	ret = iris_register_video_device(core, DECODER);
	...
	ret = iris_register_video_device(core, ENCODER);
	...
}

Inside iris_register_video_device(), video_register_device() makes the
device accessible to userspace before video_set_drvdata() sets the driver
data:

drivers/media/platform/qcom/iris/iris_probe.c:iris_register_video_device() {
	...
	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
	if (ret)
		goto err_vdev_release;

	video_set_drvdata(vdev, core);
	...
}

If a userspace application like udev immediately opens the device,
iris_open() will retrieve a NULL pointer and trigger a NULL pointer
dereference when accessing core->dev:

drivers/media/platform/qcom/iris/iris_vidc.c:iris_open() {
	struct iris_core *core = video_drvdata(filp);
	...
	ret = pm_runtime_resume_and_get(core->dev);
	...
}

Even if video_set_drvdata() completes in time, iris_probe() registers the
video devices before executing dma_set_mask_and_coherent() and
devm_pm_runtime_enable(). Could this allow iris_open() to initiate PM/DMA
operations on an uninitialized hardware state?

>  
>  	dma_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));
>  	dma_set_seg_boundary(&pdev->dev, DMA_BIT_MASK(32));

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=6

Re: [PATCH v2 05/12] media: iris: Route buffers to the matching context bank device

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

Pre-existing issues:
- [Critical] In `iris_vdec_inst_init`, the memory allocations for `fmt_src` and `fmt_dst` are not checked for failure, leading to an immediate NULL pointer dereference on allocation failure.
- [High] The `fmt_src` and `fmt_dst` allocations are leaked if initialization fails during `iris_open` or at the end of the inst_init functions.
- [High] Use-After-Free of `struct iris_core` due to `devm_kzalloc` mismatch with V4L2 file descriptor lifetimes.
--

--- Patch [5]: [PATCH v2 05/12] media: iris: Route buffers to the matching context bank device ---
commit 727c95dcb8829de9509a16605cf4666c250086ac
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

media: iris: Route buffers to the matching context bank device

The VPU issues DMA through several SMMU streams, and the hardware does
not give every stream the same addressable range. The non-pixel stream
is restricted to use 0-600MB of IOVA space, while the pixel stream can
address the full range.

> diff --git a/drivers/media/platform/qcom/iris/iris_vidc.c b/drivers/media/platform/qcom/iris/iris_vidc.c
> index 14d63dc76c9ba..26df872fb4fa1 100644
> --- a/drivers/media/platform/qcom/iris/iris_vidc.c
> +++ b/drivers/media/platform/qcom/iris/iris_vidc.c

[ ... ]

While reviewing this driver, I noticed a few pre-existing regressions in
the related code that might need attention:

In drivers/media/platform/qcom/iris/iris_vdec.c:iris_vdec_inst_init():

> 	inst->fmt_src = kzalloc_obj(*inst->fmt_src);
> 	inst->fmt_dst = kzalloc_obj(*inst->fmt_dst);
> 
> 	inst->fw_min_count = 0;
> 
> 	f = inst->fmt_src;
> 	f->type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;

[Severity: Critical]
This isn't a bug introduced by this patch, but could kzalloc_obj() return
a null pointer under memory pressure and cause a dereference when setting
f->type?

In drivers/media/platform/qcom/iris/iris_vidc.c:iris_open():

> fail_m2m_ctx_release:
> 	v4l2_m2m_ctx_release(inst->m2m_ctx);
> fail_m2m_release:
> 	v4l2_m2m_release(inst->m2m_dev);
> fail_v4l2_fh_deinit:
> 	iris_v4l2_fh_deinit(inst, filp);
> 	mutex_destroy(&inst->ctx_q_lock);
> 	mutex_destroy(&inst->lock);
> 	kfree(inst);
> 
> 	return ret;

[Severity: High]
This isn't a bug introduced by this patch, but does this error path leave
the memory allocated for inst->fmt_src and inst->fmt_dst leaked?

In drivers/media/platform/qcom/iris/iris_probe.c:iris_probe():

> 	core = devm_kzalloc(&pdev->dev, sizeof(*core), GFP_KERNEL);

[Severity: High]
This isn't a bug introduced by this patch, but since core is allocated with
devm_kzalloc, its lifetime is tied to device binding.

If the driver is unbound but a file descriptor remains open, can a
subsequent close() lead to a use-after-free?

For example, when iris_check_num_queued_internal_buffers() is called
during close:

> 	const struct iris_firmware_data *firmware_data = inst->core->iris_firmware_data;

Could inst->core have already been freed by devres at this point?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=5

Re: [PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

[Rob Herring (Arm)]

On Fri, 31 Jul 2026 23:52:17 +0530, Vikash Garodia wrote:
> The VPU issues DMA through several SMMU streams, and the hardware does
> not give every stream the same addressable range. The non-pixel stream
> is restricted to use 0-600MB of IOVA space, while the pixel stream can
> address the full range:
>     +-----------------------------------------------------------+
>     | non-pixel stream addressable range (600 MB - 3.5 GB)      |
>     | 0x25800000 - 0xe0000000                                   |
>     +-----------------------------------------------------------+
>     | pixel stream addressable range (0 - 3.5 GB)               |
>     | 0x00000000 - 0xe0000000                                   |
>     +-----------------------------------------------------------+
> A single "iommus" property on the video-codec node puts every stream in
> one IOMMU domain sharing one IOVA allocator, so nothing keeps a
> non-pixel buffer above 600 MB. Once an allocation lands below that
> boundary the hardware faults, which shows up as unhandled SMMU page
> faults and spontaneous reboots:
> https://gitlab.freedesktop.org/drm/msm/-/work_items/100
> 
> Reference qcom,venus-common.yaml, which describes the per-stream context
> bank subnodes, and drop "iommus" from the required list. The common
> schema accepts either the flat "iommus" or the "non-pixel" and "pixel"
> subnode pair, so device trees that have not been converted still
> validate.
> 
> Update the example to the subnode form, which also picks up the two
> supporting properties the subnodes need on the parent video-codec node,
> '#address-cells' and '#size-cells' of 2 and an empty "dma-ranges". Both
> are described in the common schema change.
> 
> Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")
> Cc: stable@vger.kernel.org
> Co-developed-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
> Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
> Tested-by: Daniel J Blueman <daniel@quora.org>
> Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
> ---
>  .../devicetree/bindings/media/qcom,sm8550-iris.yaml    | 18 +++++++++++++++---
>  1 file changed, 15 insertions(+), 3 deletions(-)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Documentation/devicetree/bindings/media/qcom,sm8550-iris.example.dts:67.13-24: Warning (dma_ranges_format): /example-0/video-codec@aa00000:dma-ranges: empty "dma-ranges" property but its #address-cells (2) differs from /example-0 (1)
Documentation/devicetree/bindings/media/qcom,sm8550-iris.example.dts:67.13-24: Warning (dma_ranges_format): /example-0/video-codec@aa00000:dma-ranges: empty "dma-ranges" property but its #size-cells (2) differs from /example-0 (1)

doc reference errors (make refcheckdocs):

See https://patchwork.kernel.org/project/devicetree/patch/20260731-vpu_iommu_iova_handling-v2-2-da52b5228dbd@oss.qualcomm.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.