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