[PATCH v5 3/4] dt-bindings: sound: qcom,q6apm-dai: add memory-region and relax iommus

[Ajay Kumar Nandam <ajay.nandam@oss.qualcomm.com>]

On modem-DSP (mDSP) platforms the DSP runs in a stage-2 protected
context and cannot use the SMMU. PCM buffers must live in reserved-memory
carveouts that are SCM-assigned to the appropriate VMIDs.

Add an optional memory-region property (1-2 entries) for the
control-path and data-path carveouts, and remove iommus from the
required list since mDSP platforms have neither IOMMU nor VMID DT
properties.

Signed-off-by: Ajay Kumar Nandam <ajay.nandam@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/sound/qcom,q6apm-dai.yaml | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/sound/qcom,q6apm-dai.yaml b/Documentation/devicetree/bindings/sound/qcom,q6apm-dai.yaml
index 9e5b30d9c6e6..7d0415f2463a 100644
--- a/Documentation/devicetree/bindings/sound/qcom,q6apm-dai.yaml
+++ b/Documentation/devicetree/bindings/sound/qcom,q6apm-dai.yaml
@@ -20,9 +20,19 @@ properties:
     minItems: 1
     maxItems: 2
 
+  memory-region:
+    minItems: 1
+    maxItems: 2
+    items:
+      - description:
+          Control-path buffer (audio_heap_mem) for platforms where the DSP
+          runs in a stage-2 protected context (e.g. modem-DSP).
+      - description:
+          Data-path buffer pool from which per-stream DMA buffers are
+          allocated.
+
 required:
   - compatible
-  - iommus
 
 additionalProperties: false
 

-- 
2.34.1