The shared-dmb-pool compatible string creates a Designated Movable
Block to contain a shared pool of DMA buffers.

Signed-off-by: Doug Berger <opendmb@gmail.com>
---
 .../bindings/reserved-memory/shared-dma-pool.yaml         | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/reserved-memory/shared-dma-pool.yaml b/Documentation/devicetree/bindings/reserved-memory/shared-dma-pool.yaml
index 618105f079be..85824fe05ac9 100644
--- a/Documentation/devicetree/bindings/reserved-memory/shared-dma-pool.yaml
+++ b/Documentation/devicetree/bindings/reserved-memory/shared-dma-pool.yaml
@@ -22,6 +22,14 @@ properties:
           operating system to instantiate the necessary pool management
           subsystem if necessary.
 
+      - const: shared-dmb-pool
+        description: >
+          This indicates a shared-dma-pool region that is located within
+          a Designated Movable Block. The operating system is free to
+          use unallocated memory for movable allocations in this region.
+          Devices need to be tolerant of allocation latency to use this
+          pool.
+
       - const: restricted-dma-pool
         description: >
           This indicates a region of memory meant to be used as a pool
-- 
2.25.1