[RFC][PATCH 1/3] dt-bindings: dma-buf: heaps: Describe CMA regions to be added to dmabuf heaps interface.

From: John Stultz
Date: Fri Oct 25 2019 - 18:50:24 EST


This binding specifies which CMA regions should be added to the
dmabuf heaps interface.

Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
Cc: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
Cc: Andrew F. Davis <afd@xxxxxx>
Cc: Chenbo Feng <fengc@xxxxxxxxxx>
Cc: Alistair Strachan <astrachan@xxxxxxxxxx>
Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
.../bindings/dma/dmabuf-heap-cma.txt | 31 +++++++++++++++++++
1 file changed, 31 insertions(+)
create mode 100644 Documentation/devicetree/bindings/dma/dmabuf-heap-cma.txt

diff --git a/Documentation/devicetree/bindings/dma/dmabuf-heap-cma.txt b/Documentation/devicetree/bindings/dma/dmabuf-heap-cma.txt
new file mode 100644
index 000000000000..bde7b1f1c269
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/dmabuf-heap-cma.txt
@@ -0,0 +1,31 @@
+* DMA-BUF CMA Heap
+
+Specifies a CMA region that should be added to the dma-buf heaps
+interface.
+
+Required properties:
+- compatible: Must be "dmabuf-heap-cma"
+- memory-region: phandle to a CMA reserved memory node
+
+Example:
+This example has a camera CMA node in reserved memory, which is then
+referenced by the dmabuf-heap-cma node.
+
+
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+ ...
+ cma_camera: cma-camera {
+ compatible = "shared-dma-pool";
+ reg = <0x0 0x24C00000 0x0 0x4000000>;
+ reusable;
+ };
+ ...
+ };
+
+ cma_heap {
+ compatible = "dmabuf-heap-cma";
+ memory-region = <&cma_camera>;
+ };
--
2.17.1