51 lines
1.4 KiB
Plaintext
51 lines
1.4 KiB
Plaintext
* 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-channels : deprecated
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- dma-requests : Number of DMA requests supported.
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- #dma-requests : deprecated
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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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