AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

ARM: dts: at_xdmac: add bindings documentation

Browse Source 
Add bindings documentation for the new Atmel DMA controller (XDMAC)
introduced with SAMA5D4.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Ludovic Desroches 2014-10-22 17:22:19 +02:00 committed by Vinod Koul
parent e1f7c9eee7
commit a3d3044e7d
1 changed files with 54 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

54
Documentation/devicetree/bindings/dma/atmel-xdma.txt Normal file
View File

@ -0,0 +1,54 @@
* Atmel Extensible Direct Memory Access Controller (XDMAC)
* XDMA Controller
Required properties:
- compatible: Should be "atmel,<chip>-dma".
<chip> compatible description:
- sama5d4: first SoC adding the XDMAC
- reg: Should contain DMA registers location and length.
- interrupts: Should contain DMA interrupt.
- #dma-cells: Must be <1>, used to represent the number of integer cells in
the dmas property of client devices.
- The 1st cell specifies the channel configuration register:
- bit 13: SIF, source interface identifier, used to get the memory
interface identifier,
- bit 14: DIF, destination interface identifier, used to get the peripheral
interface identifier,
- bit 30-24: PERID, peripheral identifier.
Example:
dma1: dma-controller@f0004000 {
compatible = "atmel,sama5d4-dma";
reg = <0xf0004000 0x200>;
interrupts = <50 4 0>;
#dma-cells = <2>;
};
* DMA clients
DMA clients connected to the Atmel XDMA controller must use the format
described in the dma.txt file, using a one-cell specifier for each channel.
The two cells in order are:
1. A phandle pointing to the DMA controller.
2. Channel configuration register. Configurable fields are:
- bit 13: SIF, source interface identifier, used to get the memory
interface identifier,
- bit 14: DIF, destination interface identifier, used to get the peripheral
interface identifier,
- bit 30-24: PERID, peripheral identifier.
Example:
i2c2: i2c@f8024000 {
compatible = "atmel,at91sam9x5-i2c";
reg = <0xf8024000 0x4000>;
interrupts = <34 4 6>;
dmas = <&dma1
(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1)
| AT91_XDMAC_DT_PERID(6))>,
<&dma1
(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1)
| AT91_XDMAC_DT_PERID(7))>;
dma-names = "tx", "rx";
};