Postby claudio4parallella » Wed Sep 12, 2018 3:02 pm

Code: Select all
   fpga-axi@0 {
      compatible = "simple-bus";
      #address-cells = <0x1>;
      #size-cells = <0x1>;

      axivdma@43000000 {
         compatible = "xlnx,axi-vdma";
         #address-cells = <0x1>;
         #size-cells = <0x1>;
         #dma-cells = <0x1>;
         #dma-channels = <0x1>;
         reg = <0x43000000 0x1000>;
         xlnx,include-sg = <0x0>;
         xlnx,num-fstores = <0x3>;
         linux,phandle = <0x6>;
         phandle = <0x6>;

         dma-channel@43000000 {
            compatible = "xlnx,axi-vdma-mm2s-channel";
            interrupts = <0x0 0x3b 0x4>;
            xlnx,datawidth = <0x40>;
            xlnx,genlock-mode = <0x0>;
            xlnx,include-dre = <0x0>;

      axi-clkgen@66000000 {
         compatible = "adi,axi-clkgen-1.00.a";
         reg = <0x66000000 0x10000>;
         #clock-cells = <0x0>;
         clocks = <0x2 0x11>;
         linux,phandle = <0x7>;
         phandle = <0x7>;

      axi_hdmi@6C000000 {
         compatible = "adi,axi-hdmi-1.00.a";
         reg = <0x6c000000 0x10000>;
         encoder-slave = <0x5>;
         dmas = <0x6 0x0>;
         dma-names = "video";
         clocks = <0x7>;

      audio_clock {
         compatible = "fixed-clock";
         #clock-cells = <0x0>;
         clock-frequency = <0xbb8000>;
         linux,phandle = <0x9>;
         phandle = <0x9>;

      axi-spdif-tx@0x75c00000 {
         compatible = "adi,axi-spdif-tx-1.00.a";
         reg = <0x75c00000 0x1000>;
         dmas = <0x8 0x0>;
         dma-names = "tx";
         clocks = <0x2 0xf 0x9>;
         clock-names = "axi", "spdif";
         linux,phandle = <0xa>;
         phandle = <0xa>;

      adv7511_hdmi_snd {
         compatible = "adv7511-hdmi-snd";
         audio-codec = <0x5>;
         cpu-dai = <0xa>;

These is the DeviceTree settings for the HDMI I found into kernel-hdmi-140603.

If I have well understood, sorry for my ignonarce in bitstream and FPGA, thi setting shuld correspond to a uImage.

Is there any way to add to my HEADLESS Parallella IMG for eLink Cluster this settings in order to manipulate a /dev/fb0 Framebuffer and output to XVideo?

Thanks in advance
Posts: 68
Joined: Thu Aug 10, 2017 3:48 pm


Postby zmc » Sun Oct 21, 2018 9:26 pm

The bitstream is what programs the FPGA on boot. The HDMI/FB driver uses the device tree to talk to the virtual HDMI graphics card implemented in the FPGA, You would need a bitstream that has the FPGA support. I have been able to generate my own from the sources posted using Xilinx's Vivado software, but you might be better off just getting a premade one unless you have specific requirements.

Are you running a custom Linux kernel?

The things you need to get FB output are: A HDMI bitstream to program the FPGA, the devicetree files to tell the kernel about the hardware, and a Linux kernel driver for the hardware.
Posts: 24
Joined: Thu Jul 03, 2014 10:01 pm

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