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49 lines
1.9 KiB
49 lines
1.9 KiB
* 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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- arm,pl330-broken-no-flushp: quirk for avoiding to execute DMAFLUSHP |
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- arm,pl330-periph-burst: quirk for performing burst transfer only |
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- resets: contains an entry for each entry in reset-names. |
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See ../reset/reset.txt for details. |
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- reset-names: must contain at least "dma", and optional is "dma-ocp". |
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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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