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Texas Instruments eDMA

The eDMA3 consists of two components: Channel controller (CC) and Transfer
Controller(s) (TC). The CC is the main entry for DMA users since it is
responsible for the DMA channel handling, while the TCs are responsible to
execute the actual DMA tansfer.

------------------------------------------------------------------------------
eDMA3 Channel Controller

Required properties:
- compatible:	"ti,edma3-tpcc" for the channel controller(s)
- #dma-cells:	Should be set to <2>. The first number is the DMA request
		number and the second is the TC the channel is serviced on.
- reg:		Memory map of eDMA CC
- reg-names:	"edma3_cc"
- interrupts:	Interrupt lines for CCINT, MPERR and CCERRINT.
- interrupt-names: "edma3_ccint", "edma3_mperr" and "edma3_ccerrint"
- ti,tptcs:	List of TPTCs associated with the eDMA in the following form:
		<&tptc_phandle TC_priority_number>. The highest priority is 0.

Optional properties:
- ti,hwmods:	Name of the hwmods associated to the eDMA CC
- ti,edma-memcpy-channels: List of channels allocated to be used for memcpy, iow
		these channels will be SW triggered channels. See example.
- ti,edma-reserved-slot-ranges: PaRAM slot ranges which should not be used by
		the driver, they are allocated to be used by for example the
		DSP. See example.

------------------------------------------------------------------------------
eDMA3 Transfer Controller

Required properties:
- compatible:	"ti,edma3-tptc" for the transfer controller(s)
- reg:		Memory map of eDMA TC
- interrupts:	Interrupt number for TCerrint.

Optional properties:
- ti,hwmods:	Name of the hwmods associated to the given eDMA TC
- interrupt-names: "edma3_tcerrint"

------------------------------------------------------------------------------
Example:

edma: edma@49000000 {
	compatible = "ti,edma3-tpcc";
	ti,hwmods = "tpcc";
	reg =	<0x49000000 0x10000>;
	reg-names = "edma3_cc";
	interrupts = <12 13 14>;
	interrupt-names = "edma3_ccint", "edma3_mperr", "edma3_ccerrint";
	dma-requests = <64>;
	#dma-cells = <2>;

	ti,tptcs = <&edma_tptc0 7>, <&edma_tptc1 7>, <&edma_tptc2 0>;

	/* Channel 20 and 21 is allocated for memcpy */
	ti,edma-memcpy-channels = <20 21>;
	/* The following PaRAM slots are reserved: 35-44 and 100-109 */
	ti,edma-reserved-slot-ranges = <35 10>, <100 10>;
};

edma_tptc0: tptc@49800000 {
	compatible = "ti,edma3-tptc";
	ti,hwmods = "tptc0";
	reg =	<0x49800000 0x100000>;
	interrupts = <112>;
	interrupt-names = "edm3_tcerrint";
};

edma_tptc1: tptc@49900000 {
	compatible = "ti,edma3-tptc";
	ti,hwmods = "tptc1";
	reg =	<0x49900000 0x100000>;
	interrupts = <113>;
	interrupt-names = "edm3_tcerrint";
};

edma_tptc2: tptc@49a00000 {
	compatible = "ti,edma3-tptc";
	ti,hwmods = "tptc2";
	reg =	<0x49a00000 0x100000>;
	interrupts = <114>;
	interrupt-names = "edm3_tcerrint";
};

sham: sham@53100000 {
	compatible = "ti,omap4-sham";
	ti,hwmods = "sham";
	reg = <0x53100000 0x200>;
	interrupts = <109>;
	/* DMA channel 36 executed on eDMA TC0 - low priority queue */
	dmas = <&edma 36 0>;
	dma-names = "rx";
};

mcasp0: mcasp@48038000 {
	compatible = "ti,am33xx-mcasp-audio";
	ti,hwmods = "mcasp0";
	reg = <0x48038000 0x2000>,
		<0x46000000 0x400000>;
	reg-names = "mpu", "dat";
	interrupts = <80>, <81>;
	interrupt-names = "tx", "rx";
	status = "disabled";
	/* DMA channels 8 and 9 executed on eDMA TC2 - high priority queue */
	dmas = <&edma 8 2>,
	       <&edma 9 2>;
	dma-names = "tx", "rx";
};

------------------------------------------------------------------------------
DEPRECATED binding, new DTS files must use the ti,edma3-tpcc/ti,edma3-tptc
binding.

Required properties:
- compatible : "ti,edma3"
- #dma-cells: Should be set to <1>
              Clients should use a single channel number per DMA request.
- reg: Memory map for accessing module
- interrupt-parent: Interrupt controller the interrupt is routed through
- interrupts: Exactly 3 interrupts need to be specified in the order:
              1. Transfer completion interrupt.
              2. Memory protection interrupt.
              3. Error interrupt.
Optional properties:
- ti,hwmods: Name of the hwmods associated to the EDMA
- ti,edma-xbar-event-map: Crossbar event to channel map

Deprecated properties:
Listed here in case one wants to boot an old kernel with new DTB. These
properties might need to be added to the new DTS files.
- ti,edma-regions: Number of regions
- ti,edma-slots: Number of slots
- dma-channels: Specify total DMA channels per CC

Example:

edma: edma@49000000 {
	reg = <0x49000000 0x10000>;
	interrupt-parent = <&intc>;
	interrupts = <12 13 14>;
	compatible = "ti,edma3";
	ti,hwmods = "tpcc", "tptc0", "tptc1", "tptc2";
	#dma-cells = <1>;
	ti,edma-xbar-event-map = /bits/ 16 <1 12
					    2 13>;
};