Hi,

Le mercredi 07 janvier 2026 à 15:19 +0100, Sven Püschel a écrit :

quoted

quoted

@@ -95,13 +96,16 @@ queue_init(void *priv, struct vb2_queue *src_vq,

struct vb2_queue *dst_vq)
   	src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
   	src_vq->drv_priv = ctx;
   	src_vq->ops = &rga_qops;
-	src_vq->mem_ops = &vb2_dma_sg_memops;
+	src_vq->mem_ops = &vb2_dma_contig_memops;

That's a bit I'm less knowledgeable here, since I never used the sg_memops
in
any of my work, but what is the consequence ? (appart from gaining external
iommu support)

This is only for the external iommu support, which uses the 
vb2_dma_contig_plane_dma_addr function to get a single linear address 
(instead of vb2_dma_sg_plane_desc used for the manual iommu mapping).

Without an external iommu the value is overridden afterwards to 
vb2_dma_sg_memops. I probably should move the if up to make clear that 
this is only set for the external iommu case.

Or did I misunderstand your question?

That was it, I read quickly thinking it was always vb2_dma_contig_memops now,
regardless which iommu implementation is used. If you can make it clearer that
the ops depends on the context, that would be great.

Nicolas