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+* Freescale Smart Direct Memory Access (SDMA) Controller for i.MX
+
+Required properties:
+- compatible : Should be one of
+ "fsl,imx25-sdma"
+ "fsl,imx31-sdma", "fsl,imx31-to1-sdma", "fsl,imx31-to2-sdma"
+ "fsl,imx35-sdma", "fsl,imx35-to1-sdma", "fsl,imx35-to2-sdma"
+ "fsl,imx51-sdma"
+ "fsl,imx53-sdma"
+ "fsl,imx6q-sdma"
+ "fsl,imx7d-sdma"
+ "fsl,imx8mq-sdma"
+ "fsl,imx8mm-sdma"
+ "fsl,imx8mn-sdma"
+ "fsl,imx8mp-sdma"
+ The -to variants should be preferred since they allow to determine the
+ correct ROM script addresses needed for the driver to work without additional
+ firmware.
+- reg : Should contain SDMA registers location and length
+- interrupts : Should contain SDMA interrupt
+- #dma-cells : Must be <3>.
+ The first cell specifies the DMA request/event ID. See details below
+ about the second and third cell.
+- fsl,sdma-ram-script-name : Should contain the full path of SDMA RAM
+ scripts firmware
+
+The second cell of dma phandle specifies the peripheral type of DMA transfer.
+The full ID of peripheral types can be found below.
+
+ ID transfer type
+ ---------------------
+ 0 MCU domain SSI
+ 1 Shared SSI
+ 2 MMC
+ 3 SDHC
+ 4 MCU domain UART
+ 5 Shared UART
+ 6 FIRI
+ 7 MCU domain CSPI
+ 8 Shared CSPI
+ 9 SIM
+ 10 ATA
+ 11 CCM
+ 12 External peripheral
+ 13 Memory Stick Host Controller
+ 14 Shared Memory Stick Host Controller
+ 15 DSP
+ 16 Memory
+ 17 FIFO type Memory
+ 18 SPDIF
+ 19 IPU Memory
+ 20 ASRC
+ 21 ESAI
+ 22 SSI Dual FIFO (needs firmware ver >= 2)
+ 23 Shared ASRC
+ 24 SAI
+
+The third cell specifies the transfer priority as below.
+
+ ID transfer priority
+ -------------------------
+ 0 High
+ 1 Medium
+ 2 Low
+
+Optional properties:
+
+- gpr : The phandle to the General Purpose Register (GPR) node.
+- fsl,sdma-event-remap : Register bits of sdma event remap, the format is
+ <reg shift val>.
+ reg is the GPR register offset.
+ shift is the bit position inside the GPR register.
+ val is the value of the bit (0 or 1).
+
+Examples:
+
+sdma@83fb0000 {
+ compatible = "fsl,imx51-sdma", "fsl,imx35-sdma";
+ reg = <0x83fb0000 0x4000>;
+ interrupts = <6>;
+ #dma-cells = <3>;
+ fsl,sdma-ram-script-name = "sdma-imx51.bin";
+};
+
+DMA clients connected to the i.MX SDMA controller must use the format
+described in the dma.txt file.
+
+Examples:
+
+ssi2: ssi@70014000 {
+ compatible = "fsl,imx51-ssi", "fsl,imx21-ssi";
+ reg = <0x70014000 0x4000>;
+ interrupts = <30>;
+ clocks = <&clks 49>;
+ dmas = <&sdma 24 1 0>,
+ <&sdma 25 1 0>;
+ dma-names = "rx", "tx";
+ fsl,fifo-depth = <15>;
+};
+
+Using the fsl,sdma-event-remap property:
+
+If we want to use SDMA on the SAI1 port on a MX6SX:
+
+&sdma {
+ gpr = <&gpr>;
+ /* SDMA events remap for SAI1_RX and SAI1_TX */
+ fsl,sdma-event-remap = <0 15 1>, <0 16 1>;
+};
+
+The fsl,sdma-event-remap property in this case has two values:
+- <0 15 1> means that the offset is 0, so GPR0 is the register of the
+SDMA remap. Bit 15 of GPR0 selects between UART4_RX and SAI1_RX.
+Setting bit 15 to 1 selects SAI1_RX.
+- <0 16 1> means that the offset is 0, so GPR0 is the register of the
+SDMA remap. Bit 16 of GPR0 selects between UART4_TX and SAI1_TX.
+Setting bit 16 to 1 selects SAI1_TX.