linux/Documentation/devicetree/bindings/dma/snps-dma.txt

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* Synopsys Designware DMA Controller
Required properties:
- compatible: "snps,dma-spear1340"
- reg: Address range of the DMAC registers
- interrupt-parent: Should be the phandle for the interrupt controller
that services interrupts for this device
- interrupt: Should contain the DMAC interrupt number
- nr_channels: Number of channels supported by hardware
- is_private: The device channels should be marked as private and not for by the
general purpose DMA channel allocator. False if not passed.
- chan_allocation_order: order of allocation of channel, 0 (default): ascending,
1: descending
- chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
increase from chan n->0
- block_size: Maximum block size supported by the controller
- nr_masters: Number of AHB masters supported by the controller
- data_width: Maximum data width supported by hardware per AHB master
(0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
- slave_info:
- bus_id: name of this device channel, not just a device name since
devices may have more than one channel e.g. "foo_tx". For using the
dw_generic_filter(), slave drivers must pass exactly this string as
param to filter function.
- cfg_hi: Platform-specific initializer for the CFG_HI register
- cfg_lo: Platform-specific initializer for the CFG_LO register
- src_master: src master for transfers on allocated channel.
- dst_master: dest master for transfers on allocated channel.
Example:
dma@fc000000 {
compatible = "snps,dma-spear1340";
reg = <0xfc000000 0x1000>;
interrupt-parent = <&vic1>;
interrupts = <12>;
nr_channels = <8>;
chan_allocation_order = <1>;
chan_priority = <1>;
block_size = <0xfff>;
nr_masters = <2>;
data_width = <3 3 0 0>;
slave_info {
uart0-tx {
bus_id = "uart0-tx";
cfg_hi = <0x4000>; /* 0x8 << 11 */
cfg_lo = <0>;
src_master = <0>;
dst_master = <1>;
};
spi0-tx {
bus_id = "spi0-tx";
cfg_hi = <0x2000>; /* 0x4 << 11 */
cfg_lo = <0>;
src_master = <0>;
dst_master = <0>;
};
};
};