Linux: EDMA_XBAR Still unable to work

Part Number: AM3354

Tool/software: Linux

I want to use XDMA_EVENT_INTR0 to trigger  a DMA to read GPMC data .In the 3.2 kernel I have easy to achieve and good use, but in the latest RT-LINUX 4.4.12 try to use a variety of methods are unable to achieve this function.I do not quite understand the new kernel, can you help me? thank you very much

Here is my code..

&gpmc {
    status = "okay";
    ranges = <0 0 0x08000000 0x10000000>, /* CS0: 16MB for NAND */
         <1 0 0x18000000 0x08000000>,
         <2 0 0x20000000 0x08000000>,
         <3 0 0x28000000 0x08000000>,
         <4 0 0x30000000 0x08000000>,
         <5 0 0x38000000 0x04000000>,
         <6 0 0x3c000000 0x04000000>;
    nand@0,0 {
        compatible = "ti,omap2-nand";
        ....
    };
    fpga@1,0 {
        compatible = "fpga";
        pinctrl-names = "default";
        pinctrl-0 = <&fpga_pins>;
        status = "okay";
        reg = <1 0 0x01000000>; /* CS1, offset 0, IO size 4 */
        
        bank-width = <2>;     /* GPMC_CONFIG1_DEVICESIZE(1) */

        /*gpmc,burst-write;*/
        /*gpmc,burst-read;*/
        /*gpmc,burst-wrap;*/
        ......                .......

        /* these are on the crossbar and are outlined in the
            xbar-event-map element */
        dmas = <&edma_xbar 20 0 28>;  /*XDMA_EVENT_INTR0*/
        dma-names = "fpga";

        interrupt-parent = <&gpio0>;
        interrupts = <19 IRQ_TYPE_LEVEL_HIGH>;
        

        /* reset */
        reset-gpio = <&gpio0 20 GPIO_ACTIVE_HIGH>;
    };
};

In the driver C file, I use "dma_request_chan (& pdev-> dev," fpga ");" Request DMA interrupt, the results can not be used to trigger this event through XDMA_EVENT_INTR0, I try to use "dma_request_channel (mask, NULL, NULL); "I can start DMA but I did not expect results