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- * Ingenic JZ4780 DMA Controller
- Required properties:
- - compatible: Should be "ingenic,jz4780-dma"
- - reg: Should contain the DMA controller registers location and length.
- - interrupts: Should contain the interrupt specifier of the DMA controller.
- - interrupt-parent: Should be the phandle of the interrupt controller that
- - clocks: Should contain a clock specifier for the JZ4780 PDMA clock.
- - #dma-cells: Must be <2>. Number of integer cells in the dmas property of
- DMA clients (see below).
- Optional properties:
- - ingenic,reserved-channels: Bitmask of channels to reserve for devices that
- need a specific channel. These channels will only be assigned when explicitly
- requested by a client. The primary use for this is channels 0 and 1, which
- can be configured to have special behaviour for NAND/BCH when using
- programmable firmware.
- Example:
- dma: dma@13420000 {
- compatible = "ingenic,jz4780-dma";
- reg = <0x13420000 0x10000>;
- interrupt-parent = <&intc>;
- interrupts = <10>;
- clocks = <&cgu JZ4780_CLK_PDMA>;
- #dma-cells = <2>;
- ingenic,reserved-channels = <0x3>;
- };
- DMA clients must use the format described in dma.txt, giving a phandle to the
- DMA controller plus the following 2 integer cells:
- 1. Request type: The DMA request type for transfers to/from the device on
- the allocated channel, as defined in the SoC documentation.
- 2. Channel: If set to 0xffffffff, any available channel will be allocated for
- the client. Otherwise, the exact channel specified will be used. The channel
- should be reserved on the DMA controller using the ingenic,reserved-channels
- property.
- Example:
- uart0: serial@10030000 {
- ...
- dmas = <&dma 0x14 0xffffffff
- &dma 0x15 0xffffffff>;
- dma-names = "tx", "rx";
- ...
- };
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