Unable to prepare the dma engine for the DMA transmit buffer.

[maikonadams]

I am getting the following messages when I run the testbench, do you guys have any idea what could it be ?

axidma: axidma_dma.c: axidma_prep_transfer: 236: Unable to prepare the dma engine for the DMA transmit buffer. cma: cma_release(page effd1000) cma: cma_release(page effc1000) cma: cma_alloc(cma c184d420, count 2025, align 8) cma: cma_alloc(): returned effc1000 cma: cma_alloc(cma c184d420, count 2025, align 8) cma: cma_alloc(): returned effd1000

[maikonadams]

I'm using direct transfer only , and I see the function is dmaengine_prep_slave_sg , maybe that's y.

[maikonadams]

I am using Petalinux , and this is my system-user.dtsi : /include/ "system-conf.dtsi" / { amba_pl: amba_pl {

address-cells = <1>;

    #size-cells = <1>;
    compatible = "simple-bus";
    ranges ;
    axidma_chrdev: axidma_chrdev@0 {
            compatible = "xlnx,axidma-chrdev";
            dmas = <&axi_dma_0 0 &axi_dma_0 1>;
            dma-names = "tx_channel", "rx_channel";
        };
    axi_dma_0: dma@40400000 {
        #dma-cells = <1>;
        clock-names = "s_axi_lite_aclk", "m_axi_sg_aclk", "m_axi_mm2s_aclk", "m_axi_s2mm_aclk";
        clocks = <&clkc 15>, <&clkc 15>, <&clkc 15>, <&clkc 15>;
        compatible = "xlnx,axi-dma-1.00.a";
        interrupt-names = "mm2s_introut", "s2mm_introut";
        interrupt-parent = <&intc>;
        interrupts = <0 29 4 0 30 4>;
        reg = <0x40400000 0x10000>;
        xlnx,addrwidth = <0x40>;
        xlnx,sg-length-width = <0xe>;
        dma-channel@40400000 {
            compatible = "xlnx,axi-dma-mm2s-channel";
            dma-channels = <0x1>;
            interrupts = <0 29 4>;
            xlnx,datawidth = <0x40>;
            xlnx,device-id = <0x0>;
        };
        dma-channel@40400030 {
            compatible = "xlnx,axi-dma-s2mm-channel";
            dma-channels = <0x1>;
            interrupts = <0 30 4>;
            xlnx,datawidth = <0x40>;
            xlnx,device-id = <0x1>;
        };
    };

};

};

lsmod Tainted: G
axidma 28672 0 - Live 0xbf008000 (O) uio_pdrv_genirq 16384 0 - Live 0xbf000000 when I install :

axidma: axidma_dma.c: axidma_dma_init: 718: DMA: Found 1 transmit channels and 1 receive channels. axidma: axidma_dma.c: axidma_dma_init: 720: VDMA: Found 0 transmit channels and 0 receive channels.

I feel I am close ... but

[kingofworldch]

Hello，I meet this problem，too。How to solve this problem for you？ I am confused！

[sethk2]

Most likely you've already solved this or moved on, but for me I needed to change the "Width of Buffer Length Register" for the AXI Direct Memory Access IP in Vivado. I think by default it's set to something like 14 and bumping it to 26 allowed the benchmark test to run.

[yrink]

Hello, iam getting the same Error messages as above. Ima using a System, which looks like my attached file. With the AXIS_Switches i wanna control the routing to my Test IP Cores. This should be fine so far, because my Transaction stops just after 236 Transfers. I guess my problem is in the Signals of my Test IPs. Does someone see my issue in this Code?

typedef ap_axis <32,1,1,1> AXI_T; typedef hls::stream STREAM_T;

void test2(STREAM_T &A, STREAM_T &B){

pragma HLS INTERFACE axis port=A

pragma HLS INTERFACE axis port=B

pragma HLS INTERFACE ap_ctrl_none port=return

AXI_T tmpA, tmpB;

int LEN=5000;

for(int i=0; i<LEN; i++){

pragma HLS PIPELINE

    A >> tmpA;

    tmpB.data=tmpA.data+tmpA.data;
    if(i == LEN-1){
        tmpB.last = 1;
    }
    tmpB.keep = 0xf;
    B << tmpB;

}

}

I assert the TLAST Signal on the last Transfer, so actually it should be fine.

My DMA Settings are: Width of buffer: 26 Bits-> Should be more than enough, becaus i only transfer 5000 32 Bit values Address Width: 64 Bits Memory Map Data Width: 64 Stream Data Width: 32 Burst Size:256 Allow Unaligned Transfers and enable Scatter gather are checked.

[loylosky]

Most likely you've already solved this or moved on, but for me I needed to change the "Width of Buffer Length Register" for the AXI Direct Memory Access IP in Vivado. I think by default it's set to something like 14 and bumping it to 26 allowed the benchmark test to run.

Hi, may I ask does this solution solve the issue? I met the same problem recently. I try to modify my device tree file for the first time, but it didn't work. I would really appreciate it if you could provide some advice. Thanks!

[loylosky]

I am using Petalinux , and this is my system-user.dtsi : /include/ "system-conf.dtsi" / { amba_pl: amba_pl {

address-cells = <1>;

size-cells = <1>;

compatible = "simple-bus"; ranges ; axidma_chrdev: axidma_chrdev@0 { compatible = "xlnx,axidma-chrdev"; dmas = <&axi_dma_0 0 &axi_dma_0 1>; dma-names = "tx_channel", "rx_channel"; }; axi_dma_0: dma@40400000 {

dma-cells = <1>;

clock-names = "s_axi_lite_aclk", "m_axi_sg_aclk", "m_axi_mm2s_aclk", "m_axi_s2mm_aclk"; clocks = <&clkc 15>, <&clkc 15>, <&clkc 15>, <&clkc 15>; compatible = "xlnx,axi-dma-1.00.a"; interrupt-names = "mm2s_introut", "s2mm_introut"; interrupt-parent = <&intc>; interrupts = <0 29 4 0 30 4>; reg = <0x40400000 0x10000>; xlnx,addrwidth = <0x40>; xlnx,sg-length-width = <0xe>; dma-channel@40400000 { compatible = "xlnx,axi-dma-mm2s-channel"; dma-channels = <0x1>; interrupts = <0 29 4>; xlnx,datawidth = <0x40>; xlnx,device-id = <0x0>; }; dma-channel@40400030 { compatible = "xlnx,axi-dma-s2mm-channel"; dma-channels = <0x1>; interrupts = <0 30 4>; xlnx,datawidth = <0x40>; xlnx,device-id = <0x1>; }; };

};

};

lsmod Tainted: G axidma 28672 0 - Live 0xbf008000 (O) uio_pdrv_genirq 16384 0 - Live 0xbf000000 when I install :

axidma: axidma_dma.c: axidma_dma_init: 718: DMA: Found 1 transmit channels and 1 receive channels. axidma: axidma_dma.c: axidma_dma_init: 720: VDMA: Found 0 transmit channels and 0 receive channels.

I feel I am close ... but

Hi, I got the same problem as you. I have tried several methods but none of them worked. May I ask have you solved this issue later? Thanks!