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+* SHDMA Device Tree bindings
+
+Sh-/r-mobile and r-car systems often have multiple identical DMA controller
+instances, capable of serving any of a common set of DMA slave devices, using
+the same configuration. To describe this topology we require all compatible
+SHDMA DT nodes to be placed under a DMA multiplexer node. All such compatible
+DMAC instances have the same number of channels and use the same DMA
+descriptors. Therefore respective DMA DT bindings can also all be placed in the
+multiplexer node. Even if there is only one such DMAC instance on a system, it
+still has to be placed under such a multiplexer node.
+
+* DMA multiplexer
+
+Required properties:
+- compatible:   should be "renesas,shdma-mux"
+- #dma-cells:   should be <1>, see "dmas" property below
+
+Optional properties (currently unused):
+- dma-channels: number of DMA channels
+- dma-requests: number of DMA request signals
+
+* DMA controller
+
+Required properties:
+- compatible:   should be "renesas,shdma"
+
+Example:
+        dmac: dma-mux0 {
+                compatible = "renesas,shdma-mux";
+                #dma-cells = <1>;
+                dma-channels = <6>;
+                dma-requests = <256>;
+                reg = <0 0>;    /* Needed for AUXDATA */
+                #address-cells = <1>;
+                #size-cells = <1>;
+                ranges;
+
+                dma0: shdma@fe008020 {
+                        compatible = "renesas,shdma";
+                        reg = <0xfe008020 0x270>,
+                                <0xfe009000 0xc>;
+                        interrupt-parent = <&gic>;
+                        interrupts = <0 34 4
+                                        0 28 4
+                                        0 29 4
+                                        0 30 4
+                                        0 31 4
+                                        0 32 4
+                                        0 33 4>;
+                        interrupt-names = "error",
+                                        "ch0", "ch1", "ch2", "ch3",
+                                        "ch4", "ch5";
+                };
+
+                dma1: shdma@fe018020 {
+                        ...
+                };
+
+                dma2: shdma@fe028020 {
+                        ...
+                };
+        };
+
+* DMA client
+
+Required properties:
+- dmas:         a list of <[DMA multiplexer phandle] [MID/RID value]> pairs,
+                where MID/RID values are fixed handles, specified in the SoC
+                manual
+- dma-names:    a list of DMA channel names, one per "dmas" entry
+
+Example:
+        dmas = <&dmac 0xd1
+                &dmac 0xd2>;
+        dma-names = "tx", "rx";