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The aim of this section is to properly configure custom display: LVDS and eDP panels.

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The target file to edit is linux-seco/arch/arm/boot/dts/imx6qdl-seco_lvds_display.dtsi. This last contains the list of available LVDS resolutions.

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To obtain the information about the ldb structure, you can refer to the documentation available into the Kernel:

linux-seco/Documentation/devicetree/bindings/display/imx/ldb.txt
linux-seco/Documentation/devicetree/bindings/fb/fsl_ipuv3_fb.txt_fb.txt

Is this the struct you were talking about?

Code Block

        timing9: $name { 
		      clock-frequency = <$Clock-frequency>; 
			  hactive = <$Hactive>; 
			  vactive = <$Vactive>; 
			  hback-porch = <$Hback>; 
			  hfront-porch = <$Hfront>; 
			  vback-porch = <$Vback>; 
			  vfront-porch = <$Vfront>; 
			  hsync-len = <$Hsync>; 
			  vsync-len = <$Vsync>; 
		};

Below Here below an example of lbd structure got for SVGA TFT LCD(800x600) 10.4 inches panel (datasheet avalaible here) is the sample timing data for SVGA TFT LCD(800x600) 10.4 inches (BA104S01-100):

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The resolution to use is passed from U-Boot to the kernel via bootargs. The " seco_config " command help the user to perform the selection of the video settings and resolution.
In order to add a new custom LVDS resolution, please follow steps below described:

The target file to edit is u-boot-seco/cmd/cmd_seco_config.c. This last contains the list of available LVDS resolutions to pass to kernel via bootargs (selection is performed via seco_config command).

Code Block
cd u-boot-seco/cmd/ vi cmd_seco_config.c

Add the custom resolution

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settings by appending new

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items into the following structure:

Code Block

language	c

static lvds_video_spec_t lvds_video_spec_list [] = {
        { "WVGA    [800x480]",   "LDB-WVGA",    "RGB666",      "datamap=spwg",  "",   1 },
        { "SVGA    [800x600]",   "LDB-SVGA",    "RGB666",      "datamap=spwg",  "",   1 },
        { "XGA     [1024x768]",  "LDB-XGA",     "RGB666",      "datamap=spwg",  "",   1 },
        { "WXGA    [1368x768]",  "LDB-WXGA",    "RGB24",       "datamap=jeida", "",   1 },
        { "WXGAP60 [1280x800]",  "LDB-1280P60", "RGB24,bpp=32","datamap=spwg",  "",   1 },
        { "SXGA    [1280x1024]", "LDB-SXGA",    "RGB24",       "datamap=jeida", "",   1 },
        { "HD1080  [1920x1080]", "LDB-1080P60", "RGB24",       "datamap=spwg", "ldb=spl0", 2 },
        {<DISPLAY NAME>, <KERNEL DISPLAY NAME>, <PIXEL FORMAT>, <DATA MAPPING>, "LDB SETTING", <CHANNEL NUMBER>}
};

withThe fields <DISPLAY NAME>, <KERNEL DISPLAY NAME>, <PIXEL FORMAT>, <DATA MAPPING>, "LDB SETTING", <CHANNEL NUMBER> are here described:

Field

Description

DISPLAY NAME

name Name shown into the resolution list when seco_config command is used

KERNEL DISPLAY NAME

name Name of the resolution added into the kernel file arch/arm/boot/dts/imx6qdl-seco_lvds_display.dtsi ($name variable)

PIXEL FORMAT

display Display interface pixel format:

Code Block

    RGB666          IPU_PIX_FMT_RGB666
    RGB565          IPU_PIX_FMT_RGB565
    RGB24           IPU_PIX_FMT_RGB24
    BGR24           IPU_PIX_FMT_BGR24
    GBR24           IPU_PIX_FMT_GBR24
    YUV444          IPU_PIX_FMT_YUV444
    YUYV            IPU_PIX_FMT_YUYV
    UYVY            IPU_PIX_FMT_UYVY
    YVYV            IPU_PIX_FMT_YVYU
    VYUY            IPU_PIX_FMT_VYUY

DATA MAPPING

color Color signals mapping order [ jeida | spwg | vesa ]

LDB SETTING

i.MX6 LVDS setting. Leave empty to use the default (display single channel)

(ldb=spl0 -> split mode, used for display dual channel)

CHANNEL NUMBER

number Number of channel to use (leave 1 for default configuration)

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Also the U-Boot uses the Display to display the Splash Screen. So, if the scope is to use also the custom resolution at U-Boot level, this task have to be performed:

Editing the file board/seco/common/display.c

A new node into “struct display_info_t const displays[]” must to be added. Under the sub-structure

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Versions Compared

Old Version 36

New Version 37

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