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-rw-r--r--Documentation/devicetree/bindings/dma/dma.txt28
-rw-r--r--Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt52
2 files changed, 80 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/dma.txt b/Documentation/devicetree/bindings/dma/dma.txt
index 8210427..6312fb0 100644
--- a/Documentation/devicetree/bindings/dma/dma.txt
+++ b/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
diff --git a/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
new file mode 100644
index 0000000..63a4892
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
@@ -0,0 +1,52 @@
+Texas Instruments DMA Crossbar (DMA request router)
+
+Required properties:
+- compatible: "ti,dra7-dma-crossbar" for DRA7xx DMA crossbar
+- reg: Memory map for accessing module
+- #dma-cells: Should be set to <1>.
+ Clients should use the crossbar request number (input)
+- dma-requests: Number of DMA requests the crossbar can receive
+- dma-masters: phandle pointing to the DMA controller
+
+The DMA controller node need to have the following poroperties:
+- dma-requests: Number of DMA requests the controller can handle
+
+Optional properties:
+- ti,dma-safe-map: Safe routing value for unused request lines
+
+Example:
+
+/* DMA controller */
+sdma: dma-controller@4a056000 {
+ compatible = "ti,omap4430-sdma";
+ reg = <0x4a056000 0x1000>;
+ interrupts = <GIC_SPI 7 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>;
+ #dma-cells = <1>;
+ dma-channels = <32>;
+ dma-requests = <127>;
+};
+
+/* DMA crossbar */
+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 */
+uart1: serial@4806a000 {
+ compatible = "ti,omap4-uart";
+ reg = <0x4806a000 0x100>;
+ interrupts-extended = <&gic GIC_SPI 67 IRQ_TYPE_LEVEL_HIGH>;
+ ti,hwmods = "uart1";
+ clock-frequency = <48000000>;
+ status = "disabled";
+ dmas = <&sdma_xbar 49>, <&sdma_xbar 50>;
+ dma-names = "tx", "rx";
+};
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