Documentation/devicetree/bindings/dma/k3dma.txt

Source file repositories/reference/linux-study-clean/Documentation/devicetree/bindings/dma/k3dma.txt

File Facts

System
Linux kernel
Corpus path
Documentation/devicetree/bindings/dma/k3dma.txt
Extension
.txt
Size
1264 bytes
Lines
48
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

See dma.txt first

Required properties:
- compatible: Must be one of
-              "hisilicon,k3-dma-1.0"
-              "hisilicon,hisi-pcm-asp-dma-1.0"
- reg: Should contain DMA registers location and length.
- interrupts: Should contain one interrupt shared by all channel
- #dma-cells: see dma.txt, should be 1, para number
- dma-channels: physical channels supported
- dma-requests: virtual channels supported, each virtual channel
		have specific request line
- clocks: clock required

Example:

Controller:
		dma0: dma@fcd02000 {
			compatible = "hisilicon,k3-dma-1.0";
			reg = <0xfcd02000 0x1000>;
			#dma-cells = <1>;
			dma-channels = <16>;
			dma-requests = <27>;
			interrupts = <0 12 4>;
			clocks = <&pclk>;
		};

Client:
Use specific request line passing from dmax
For example, i2c0 read channel request line is 18, while write channel use 19

		i2c0: i2c@fcb08000 {
			compatible = "snps,designware-i2c";
			dmas =	<&dma0 18          /* read channel */
				 &dma0 19>;        /* write channel */
			dma-names = "rx", "tx";
		};

		i2c1: i2c@fcb09000 {
			compatible = "snps,designware-i2c";
			dmas =	<&dma0 20          /* read channel */
				 &dma0 21>;        /* write channel */
			dma-names = "rx", "tx";
		};

Annotation

Implementation Notes