- Atmel Direct Memory Access Controller (DMA)
Required properties:
- compatible: Should be “atmel,
-dma”. - reg: Should contain DMA registers location and length.
- interrupts: Should contain DMA interrupt.
- #dma-cells: Must be <2>, used to represent the number of integer cells in
the dmas property of client devices.
Example:
dma0: dma@ffffec00 {
compatible = “atmel,at91sam9g45-dma”;
reg = <0xffffec00 0x200>;
interrupts = <21>;
#dma-cells = <2>;
};
DMA clients connected to the Atmel DMA controller must use the format
described in the dma.txt file, using a three-cell specifier for each channel:
a phandle plus two interger cells.
The three cells in order are:
- A phandle pointing to the DMA controller.
- The memory interface (16 most significant bits), the peripheral interface
(16 less significant bits). - The peripheral identifier for the hardware handshaking interface. The
identifier can be different for tx and rx.
Example:
i2c0@i2c@f8010000 {
compatible = “atmel,at91sam9x5-i2c”;
reg = <0xf8010000 0x100>;
interrupts = <9 4 6>;
dmas = <&dma0 1 7>,
<&dma0 1 8>;
dma-names = “tx”, “rx”;
};
