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Diffstat (limited to 'Documentation/devicetree/bindings/dma/nbpfaxi.txt')
-rw-r--r-- | Documentation/devicetree/bindings/dma/nbpfaxi.txt | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/nbpfaxi.txt b/Documentation/devicetree/bindings/dma/nbpfaxi.txt new file mode 100644 index 000000000..d2e1e62e3 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/nbpfaxi.txt @@ -0,0 +1,69 @@ +* Renesas "Type-AXI" NBPFAXI* DMA controllers + +* DMA controller + +Required properties + +- compatible: must be one of + "renesas,nbpfaxi64dmac1b4" + "renesas,nbpfaxi64dmac1b8" + "renesas,nbpfaxi64dmac1b16" + "renesas,nbpfaxi64dmac4b4" + "renesas,nbpfaxi64dmac4b8" + "renesas,nbpfaxi64dmac4b16" + "renesas,nbpfaxi64dmac8b4" + "renesas,nbpfaxi64dmac8b8" + "renesas,nbpfaxi64dmac8b16" +- #dma-cells: must be 2: the first integer is a terminal number, to which this + slave is connected, the second one is flags. Flags is a bitmask + with the following bits defined: + +#define NBPF_SLAVE_RQ_HIGH 1 +#define NBPF_SLAVE_RQ_LOW 2 +#define NBPF_SLAVE_RQ_LEVEL 4 + +Optional properties: +- max-burst-mem-read: limit burst size for memory reads + (DMA_MEM_TO_MEM/DMA_MEM_TO_DEV) to this value, specified in bytes, rather + than using the maximum burst size allowed by the hardware's buffer size. +- max-burst-mem-write: limit burst size for memory writes + (DMA_DEV_TO_MEM/DMA_MEM_TO_MEM) to this value, specified in bytes, rather + than using the maximum burst size allowed by the hardware's buffer size. + If both max-burst-mem-read and max-burst-mem-write are set, DMA_MEM_TO_MEM + will use the lower value. + +You can use dma-channels and dma-requests as described in dma.txt, although they +won't be used, this information is derived from the compatibility string. + +Example: + + dma: dma-controller@48000000 { + compatible = "renesas,nbpfaxi64dmac8b4"; + reg = <0x48000000 0x400>; + interrupts = <0 12 0x4 + 0 13 0x4 + 0 14 0x4 + 0 15 0x4 + 0 16 0x4 + 0 17 0x4 + 0 18 0x4 + 0 19 0x4>; + #dma-cells = <2>; + dma-channels = <8>; + dma-requests = <8>; + }; + +* DMA client + +Required properties: + +dmas and dma-names are required, as described in dma.txt. + +Example: + +#include <dt-bindings/dma/nbpfaxi.h> + +... + dmas = <&dma 0 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL) + &dma 1 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL)>; + dma-names = "rx", "tx"; |