* STMicroelectronics Flexible Direct Memory Access Device Tree bindings The FDMA is a general-purpose direct memory access controller capable of supporting 16 independent DMA channels. It accepts up to 32 DMA requests. The FDMA is based on a Slim processor which requires a firmware. * FDMA Controller Required properties: - compatible : Should be one of - st,stih407-fdma-mpe31-11, "st,slim-rproc"; - st,stih407-fdma-mpe31-12, "st,slim-rproc"; - st,stih407-fdma-mpe31-13, "st,slim-rproc"; - reg : Should contain an entry for each name in reg-names - reg-names : Must contain "slimcore", "dmem", "peripherals", "imem" entries - interrupts : Should contain one interrupt shared by all channels - dma-channels : Number of channels supported by the controller - #dma-cells : Must be <3>. See DMA client section below - clocks : Must contain an entry for each clock See: Documentation/devicetree/bindings/clock/clock-bindings.txt Example: fdma0: dma-controller@8e20000 { compatible = "st,stih407-fdma-mpe31-11", "st,slim-rproc"; reg = <0x8e20000 0x8000>, <0x8e30000 0x3000>, <0x8e37000 0x1000>, <0x8e38000 0x8000>; reg-names = "slimcore", "dmem", "peripherals", "imem"; clocks = <&clk_s_c0_flexgen CLK_FDMA>, <&clk_s_c0_flexgen CLK_EXT2F_A9>, <&clk_s_c0_flexgen CLK_EXT2F_A9>, <&clk_s_c0_flexgen CLK_EXT2F_A9>; interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>; dma-channels = <16>; #dma-cells = <3>; }; * DMA client Required properties: - dmas: Comma separated list of dma channel requests - dma-names: Names of the aforementioned requested channels Each dmas request consists of 4 cells: 1. A phandle pointing to the FDMA controller 2. The request line number 3. A 32bit mask specifying (see include/linux/platform_data/dma-st-fdma.h) -bit 2-0: Holdoff value, dreq will be masked for 0x0: 0-0.5us 0x1: 0.5-1us 0x2: 1-1.5us -bit 17: data swap 0x0: disabled 0x1: enabled -bit 21: Increment Address 0x0: no address increment between transfers 0x1: increment address between transfers -bit 22: 2 STBus Initiator Coprocessor interface 0x0: high priority port 0x1: low priority port 4. transfers type 0 free running 1 paced Example: sti_uni_player2: sti-uni-player@2 { compatible = "st,sti-uni-player"; #sound-dai-cells = <0>; st,syscfg = <&syscfg_core>; clocks = <&clk_s_d0_flexgen CLK_PCM_2>; assigned-clocks = <&clk_s_d0_flexgen CLK_PCM_2>; assigned-clock-parents = <&clk_s_d0_quadfs 2>; assigned-clock-rates = <50000000>; reg = <0x8D82000 0x158>; interrupts = <GIC_SPI 86 IRQ_TYPE_NONE>; dmas = <&fdma0 4 0 1>; dai-name = "Uni Player #1 (DAC)"; dma-names = "tx"; st,uniperiph-id = <2>; st,version = <5>; st,mode = "PCM"; };