45 lines
1.6 KiB
Plaintext
45 lines
1.6 KiB
Plaintext
* ARM PrimeCell PL330 DMA Controller
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The ARM PrimeCell PL330 DMA controller can move blocks of memory contents
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between memory and peripherals or memory to memory.
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Required properties:
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- compatible: should include both "arm,pl330" and "arm,primecell".
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- reg: physical base address of the controller and length of memory mapped
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region.
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- interrupts: interrupt number to the cpu.
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Optional properties:
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- dma-coherent : Present if dma operations are coherent
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- #dma-cells: must be <1>. used to represent the number of integer
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cells in the dmas property of client device.
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- dma-channels: contains the total number of DMA channels supported by the DMAC
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- dma-requests: contains the total number of DMA requests supported by the DMAC
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Example:
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pdma0: pdma@12680000 {
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compatible = "arm,pl330", "arm,primecell";
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reg = <0x12680000 0x1000>;
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interrupts = <99>;
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#dma-cells = <1>;
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#dma-channels = <8>;
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#dma-requests = <32>;
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};
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Client drivers (device nodes requiring dma transfers from dev-to-mem or
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mem-to-dev) should specify the DMA channel numbers and dma channel names
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as shown below.
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[property name] = <[phandle of the dma controller] [dma request id]>;
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[property name] = <[dma channel name]>
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where 'dma request id' is the dma request number which is connected
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to the client controller. The 'property name' 'dmas' and 'dma-names'
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as required by the generic dma device tree binding helpers. The dma
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names correspond 1:1 with the dma request ids in the dmas property.
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Example: dmas = <&pdma0 12
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&pdma1 11>;
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dma-names = "tx", "rx";
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