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

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

diff --git a/kernel/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt b/kernel/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
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+Texas Instruments DMA Crossbar (DMA request router)
+
+Required properties:
+- compatible:  "ti,dra7-dma-crossbar" for DRA7xx DMA crossbar
+               "ti,am335x-edma-crossbar" for AM335x and AM437x
+- reg:         Memory map for accessing module
+- #dma-cells:  Should be set to to match with the DMA controller's dma-cells
+               for ti,dra7-dma-crossbar and <3> for ti,am335x-edma-crossbar.
+- 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
+
+Notes:
+When requesting channel via ti,dra7-dma-crossbar, the DMA clinet must request
+the DMA event number as crossbar ID (input to the DMA crossbar).
+
+For ti,am335x-edma-crossbar: the meaning of parameters of dmas for clients:
+dmas = <&edma_xbar 12 0 1>; where <12> is the DMA request number, <0> is the TC
+the event should be assigned and <1> is the mux selection for in the crossbar.
+When mux 0 is used the DMA channel can be requested directly from edma node.
+
+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";
+       /* Requesting crossbar input 49 and 50 */
+       dmas = <&sdma_xbar 49>, <&sdma_xbar 50>;
+       dma-names = "tx", "rx";
+};