These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / dma / dma.txt

diff --git a/kernel/Documentation/devicetree/bindings/dma/dma.txt b/kernel/Documentation/devicetree/bindings/dma/dma.txt
index 8210427..6312fb0 100644 (file)
--- a/kernel/Documentation/devicetree/bindings/dma/dma.txt
+++ b/kernel/Documentation/devicetree/bindings/dma/dma.txt
@@ -31,6 +31,34 @@ Example:
                dma-requests = <127>;
        };
 
+* DMA router
+
+DMA routers are transparent IP blocks used to route DMA request lines from
+devices to the DMA controller. Some SoCs (like TI DRA7x) have more peripherals
+integrated with DMA requests than what the DMA controller can handle directly.
+
+Required property:
+- dma-masters:         phandle of the DMA controller or list of phandles for
+                       the DMA controllers the router can direct the signal to.
+- #dma-cells:          Must be at least 1. Used to provide DMA router specific
+                       information. See DMA client binding below for more
+                       details.
+
+Optional properties:
+- dma-requests:        Number of incoming request lines the router can handle.
+- In the node pointed by the dma-masters:
+       - dma-requests: The router driver might need to look for this in order
+                       to configure the routing.
+
+Example:
+       sdma_xbar: dma-router@4a002b78 {
+               compatible = "ti,dra7-dma-crossbar";
+               reg = <0x4a002b78 0xfc>;
+               #dma-cells = <1>;
+               dma-requests = <205>;
+               ti,dma-safe-map = <0>;
+               dma-masters = <&sdma>;
+       };
 
 * DMA client