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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/devicetree/bindings/dma/atmel-xdma.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+* 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 = <1>;
+};
+
+
+* 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";
+};