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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/snps-dma.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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+* Synopsys Designware DMA Controller
+
+Required properties:
+- compatible: "snps,dma-spear1340"
+- reg: Address range of the DMAC registers
+- interrupt: Should contain the DMAC interrupt number
+- dma-channels: Number of channels supported by hardware
+- dma-requests: Number of DMA request lines supported, up to 16
+- dma-masters: Number of AHB masters supported by the controller
+- #dma-cells: must be <3>
+- 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
+- data_width: Maximum data width supported by hardware per AHB master
+ (0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
+
+
+Optional properties:
+- interrupt-parent: Should be the phandle for the interrupt controller
+ that services interrupts for this device
+- is_private: The device channels should be marked as private and not for by the
+ general purpose DMA channel allocator. False if not passed.
+
+Example:
+
+ dmahost: dma@fc000000 {
+ compatible = "snps,dma-spear1340";
+ reg = <0xfc000000 0x1000>;
+ interrupt-parent = <&vic1>;
+ interrupts = <12>;
+
+ dma-channels = <8>;
+ dma-requests = <16>;
+ dma-masters = <2>;
+ #dma-cells = <3>;
+ chan_allocation_order = <1>;
+ chan_priority = <1>;
+ block_size = <0xfff>;
+ data_width = <3 3>;
+ };
+
+DMA clients connected to the Designware DMA controller must use the format
+described in the dma.txt file, using a four-cell specifier for each channel.
+The four cells in order are:
+
+1. A phandle pointing to the DMA controller
+2. The DMA request line number
+3. Source master for transfers on allocated channel
+4. Destination master for transfers on allocated channel
+
+Example:
+
+ serial@e0000000 {
+ compatible = "arm,pl011", "arm,primecell";
+ reg = <0xe0000000 0x1000>;
+ interrupts = <0 35 0x4>;
+ status = "disabled";
+ dmas = <&dmahost 12 0 1>,
+ <&dmahost 13 0 1 0>;
+ dma-names = "rx", "rx";
+ };