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48 lines
1.3 KiB
48 lines
1.3 KiB
* Freescale Direct Memory Access (DMA) Controller for i.MX |
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This document will only describe differences to the generic DMA Controller and |
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DMA request bindings as described in dma/dma.txt . |
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* DMA controller |
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Required properties: |
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- compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27 |
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- reg : Should contain DMA registers location and length |
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- interrupts : First item should be DMA interrupt, second one is optional and |
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should contain DMA Error interrupt |
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- #dma-cells : Has to be 1. imx-dma does not support anything else. |
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Optional properties: |
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- #dma-channels : Number of DMA channels supported. Should be 16. |
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- #dma-requests : Number of DMA requests supported. |
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Example: |
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dma: dma@10001000 { |
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compatible = "fsl,imx27-dma"; |
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reg = <0x10001000 0x1000>; |
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interrupts = <32 33>; |
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#dma-cells = <1>; |
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#dma-channels = <16>; |
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}; |
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* DMA client |
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Clients have to specify the DMA requests with phandles in a list. |
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Required properties: |
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- dmas: List of one or more DMA request specifiers. One DMA request specifier |
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consists of a phandle to the DMA controller followed by the integer |
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specifying the request line. |
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- dma-names: List of string identifiers for the DMA requests. For the correct |
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names, have a look at the specific client driver. |
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Example: |
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sdhci1: sdhci@10013000 { |
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... |
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dmas = <&dma 7>; |
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dma-names = "rx-tx"; |
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... |
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};
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