On Mon, Aug 17, 2026 at 10:17:40AM +0530, Ekansh Gupta wrote:

Register the QDA compute context bank bus (qda-compute-cb) with the IOMMU subsystem by adding it to the iommu_buses[] array.

The QDA driver creates synthetic devices on this bus to represent IOMMU context banks (CBs). Each CB device needs its own IOMMU domain so that the DSP memory manager can enforce per-session address space isolation. Without this registration, the IOMMU subsystem does not probe CB devices for IOMMU groups and of_dma_configure() in the bus dma_configure callback has no IOMMU domain to attach to.

Assisted-by: Claude:claude-sonnet-5 Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@oss.qualcomm.com Signed-off-by: Ekansh Gupta ekansh.gupta@oss.qualcomm.com

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drivers/iommu/iommu.c | 4 ++++ 1 file changed, 4 insertions(+)

Acked-by: Joerg Roedel joerg.roedel@amd.com