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authorLinus Torvalds <torvalds@linux-foundation.org>2013-07-07 22:11:43 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-07-07 22:11:43 +0400
commitd2b4a646717153a1a180b64d4a8464054dbd700e (patch)
treea019907da37389f59ddb429c7d10de178514af1e /Documentation/devicetree/bindings/dma/shdma.txt
parent8dce5f3dee21bf976193ddb06426b9727cf5d1a2 (diff)
parent67eacc1583909d0588c8d5d80c16298c899a6382 (diff)
downloadlinux-d2b4a646717153a1a180b64d4a8464054dbd700e.tar.xz
Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine updates from Vinod Koul: "Once you have some time from extended weekend celebrations please consider pulling the following to get: - Various fixes and PCI driver for dw_dmac by Andy - DT binding for imx-dma by Markus & imx-sdma by Shawn - DT fixes for dmaengine by Lars - jz4740 dmac driver by Lars - and various fixes across the drivers" What "extended weekend celebrations"? I'm in the merge window, who has time for extended celebrations.. * 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (40 commits) DMA: shdma: add DT support DMA: shdma: shdma_chan_filter() has to be in shdma-base.h DMA: shdma: (cosmetic) don't re-calculate a pointer dmaengine: at_hdmac: prepare clk before calling enable dmaengine/trivial: at_hdmac: add curly brackets to if/else expressions dmaengine: at_hdmac: remove unsuded atc_cleanup_descriptors() dmaengine: at_hdmac: add FIFO configuration parameter to DMA DT binding ARM: at91: dt: add header to define at_hdmac configuration MIPS: jz4740: Correct clock gate bit for DMA controller MIPS: jz4740: Remove custom DMA API MIPS: jz4740: Register jz4740 DMA device dma: Add a jz4740 dmaengine driver MIPS: jz4740: Acquire and enable DMA controller clock dma: mmp_tdma: disable irq when disabling dma channel dmaengine: PL08x: Avoid collisions with get_signal() macro dmaengine: dw: select DW_DMAC_BIG_ENDIAN_IO automagically dma: dw: add PCI part of the driver dma: dw: split driver to library part and platform code dma: move dw_dmac driver to an own directory dw_dmac: don't check resource with devm_ioremap_resource ...
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+* SHDMA Device Tree bindings
+
+Sh-/r-mobile and r-car systems often have multiple identical DMA controller
+instances, capable of serving any of a common set of DMA slave devices, using
+the same configuration. To describe this topology we require all compatible
+SHDMA DT nodes to be placed under a DMA multiplexer node. All such compatible
+DMAC instances have the same number of channels and use the same DMA
+descriptors. Therefore respective DMA DT bindings can also all be placed in the
+multiplexer node. Even if there is only one such DMAC instance on a system, it
+still has to be placed under such a multiplexer node.
+
+* DMA multiplexer
+
+Required properties:
+- compatible: should be "renesas,shdma-mux"
+- #dma-cells: should be <1>, see "dmas" property below
+
+Optional properties (currently unused):
+- dma-channels: number of DMA channels
+- dma-requests: number of DMA request signals
+
+* DMA controller
+
+Required properties:
+- compatible: should be "renesas,shdma"
+
+Example:
+ dmac: dma-mux0 {
+ compatible = "renesas,shdma-mux";
+ #dma-cells = <1>;
+ dma-channels = <6>;
+ dma-requests = <256>;
+ reg = <0 0>; /* Needed for AUXDATA */
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ dma0: shdma@fe008020 {
+ compatible = "renesas,shdma";
+ reg = <0xfe008020 0x270>,
+ <0xfe009000 0xc>;
+ interrupt-parent = <&gic>;
+ interrupts = <0 34 4
+ 0 28 4
+ 0 29 4
+ 0 30 4
+ 0 31 4
+ 0 32 4
+ 0 33 4>;
+ interrupt-names = "error",
+ "ch0", "ch1", "ch2", "ch3",
+ "ch4", "ch5";
+ };
+
+ dma1: shdma@fe018020 {
+ ...
+ };
+
+ dma2: shdma@fe028020 {
+ ...
+ };
+ };
+
+* DMA client
+
+Required properties:
+- dmas: a list of <[DMA multiplexer phandle] [MID/RID value]> pairs,
+ where MID/RID values are fixed handles, specified in the SoC
+ manual
+- dma-names: a list of DMA channel names, one per "dmas" entry
+
+Example:
+ dmas = <&dmac 0xd1
+ &dmac 0xd2>;
+ dma-names = "tx", "rx";