720x576i in T20

What have I done:

  1. I add 720x576i to to drivers/video/tegra/dc/mode.c

.

{
     /* 720x576i @ 50 Hz , pixel clk @ 13.5MHz */
     "LCD-PAL", 50, 720, 576, 74074, 138, 24, 39, 4, 126, 6,
     0,
     FB_VMODE_INTERLACED,
     0,},
  1. save in in uboot setenv vidargs video=tegrafb0:720x576-32@50 ; saveenv; reset

  2. restart and check fbset

    mode “720x576-50”
    # D: 27.000 MHz, H: 31.250 kHz, V: 50.000 Hz
    geometry 720 576 720 1152 32
    timings 37037 68 12 39 5 64 5
    rgba 8/0,8/8,8/16,8/24
    endmode

Where is the problem ?
I need pixel clk 13.5MHz but i see in fbset 2x13.5MHz
Who knows how to set the resolution ? 720x576i

  • Alternative approach to the problem: I used cmd

    fbset -g 720 576 720 576 32 -t 74074 68 12 39 5 64 5 -laced true -hsync false -vsync false

  • and check result from fbset

mode "720x576-50"
    # D: 13.500 MHz, H: 15.625 kHz, V: 50.000 Hz
    geometry 720 576 720 1152 32
    timings 74074 68 12 39 5 64 5
    laced true
    rgba 8/0,8/8,8/16,8/24
endmode

D: 13.500 MHz, H: 15.625 kHz, V: 50.000 Hz All correct
But i test oscilloscope and have V: 25Hz

Unfortunately, using fbset for run-time configuration is not supported:

https://developer.toradex.com/knowledge-base/display-output-resolution-and-timings-linux#Tegra_Framebuffer_Configuration_at_Runtime

I doubt doing interlaced like that or at all is supported.