Re: [PATCH v4 1/3] dt-bindings: media: qcom,qcm2290-venus: document shikra Iris compatible

From: Bryan O'Donoghue

Date: Fri Jul 31 2026 - 10:02:43 EST


On 31/07/2026 14:39, Bryan O'Donoghue wrote:
On 21/07/2026 18:32, Vikash Garodia wrote:
diff --git a/Documentation/devicetree/bindings/media/qcom,venus- common.yaml b/Documentation/devicetree/bindings/media/qcom,venus- common.yaml
index 59a3fde846d2196ab1e4588eb396012ba6860712..0be2f9119e78233928d23af86836ac294aa769ee 100644
--- a/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
+++ b/Documentation/devicetree/bindings/media/qcom,venus-common.yaml
@@ -37,7 +37,10 @@ properties:
      maxItems: 20

    memory-region:
-    maxItems: 1
+    minItems: 1
+    items:
+      - description: Firmware-loaded codec carveout
+      - description: IOMMU IOVA reservation region

So we discussed separately the pixel and non-pixel sub-nodes as well as this basically alternate means of memory delination.

What I'd like is a clear statement

- Committing to this scheme for existing platforms
- Adding the pixel and sub-pixel to the shared
- Backporting at least one method to -stable

For that reason this extension should at a minimum be its own commit with a well articulated commit log.

Since this is minItems: 1 it is conceviable to land both this and the sub-node into the same file.

But my continued feedback and objection is not being clear about what's being done and having two separate methods without a clear roadmap.

You have your sub-node RFC and this change - I won't say sneaking in here but, its a surreptitious change as given as-is.

- Which method
- Both ? Then what goes to -stable

We also discussed offline the fact that right-now the lack of a means of addressing this in upstream means we are in effect leaving a known critical bug open to the vagaries of IOVA allocation @ runtime across every single venus and iris there is.

So to me minItems: 1 for -stable _in_this_kernel_cycle_ is warranted.

---
bod

Just thinking about our conversation on this topic..

Truth be told, I don't think any new features should be merged to venus or iris until this gets a resolution applicable to -stable. Its just not kosher to pretend everything is fine and keep merging new features with a known critical error festering unaddressed. Fixes: yes, other stuff no.

Bug fixes > New features many times over.

This absolutely has to go to the top of the queue, its going on for months unresolved - what use is a new video codec to a user on a system where we can mess up the IOVA/SID mappings and trigger a hard reset ? Its not just that its a bug, its that its a system resetting bug.

I'm going to have to insist.

---
bod