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        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>; 
		};

setenv panel "<resolution name>
saveen

MX6QDLS SBC-A62 U-Boot > seco_config

...

 __________________________________________________
                     Chose Video Setting.
 __________________________________________________
1) no display
2) LVDS
3) HDMI
4) LVDS - LVDS (clone)
5) LVDS - LVDS (dual)
6) LVDS - HDMI
7) HDMI - LVDS
> 2

 __________________________________________________
        Chose LVDS resolution for LVDS1.
 __________________________________________________
1) WVGA	   [800x480]
2) SVGA	   [800x600]
3) XGA	   [1024x768]
4) WXGA	   [1368x768]
5) WXGAP60 [1280x800]
6) SXGA	   [1280x1024]
7) HD1080  [1920x1080]
8) NEW_RESOLUTION
> 8

...

Saving Environment to MMC... Writing to MMC(1)... OK

panel_edp: edp_panel {
      compatible = "boe,ev156fhm";
      #address-cells = <1>;
      #size-cells = <0>;
};

panel_lvds: lvds_panel {
      compatible = "auo,p215hca-high";
      #address-cells = <1>;
      #size-cells = <0>;
};

linux-seco/drivers/gpu/drm/panel/panel-simple.c

static const struct display_timing auo_p215hca_high_timing = {
        .pixelclock = { 139000000, 160000000, 165000000 },
        .hactive = { 1920, 1920, 1920 },
        .hfront_porch = { 1, 85, 90 },
        .hsync_len = { 1, 10, 45 },
        .hback_porch = { 1, 85, 150 },
        .vactive = { 1080, 1080, 1080 },
        .vfront_porch = { 3, 20, 50 },
        .vsync_len = { 6, 10,60  },
        .vback_porch = { 11, 20, 37 },
        .flags = DISPLAY_FLAGS_HSYNC_LOW |
                   DISPLAY_FLAGS_VSYNC_LOW |
                   DISPLAY_FLAGS_DE_LOW |
                   DISPLAY_FLAGS_PIXDATA_NEGEDGE,
};

static const struct panel_desc auo_p215hca_high = {
        .timings = &auo_p215hca_high_timing,
        .num_timings = 1,
        .bpc = 8,
        .size = {
                .width = 68,
                .height = 121,
        },
        .delay = {
                /*
                 * The panel spec recommends one second delay
                 * to the below items.  However, it's a bit too
                 * long in pratical.  Based on tests, it turns
                 * out 100 milliseconds is fine.
                 */
                .prepare = 100,
                .enable = 100,
                .unprepare = 100,
                .disable = 100,
        },
        .bus_format = MEDIA_BUS_FMT_RGB888_1X24,//MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
};

static const struct of_device_id platform_of_match[] = {
	{
    }, {
                .compatible = "auo,p215hca-high",
                .data = &auo_p215hca_high,
       }, {
		/* sentinel */
	}
};

linux-seco/arch/arm64/boot/dts/seco/overlays/seco-imx8mm-c61-lcdif-sn65dsi84-overlay.dts

target = <&adv_bridge>;
      __overlay__ {
              #address-cells = <1>;
              #size-cells = <0>;
              lvds,datamap = "jeida";
              lvds,dual-channel;
              lvds,channel-swap;
              lvds,preserve-dsi-timings;
                                      /*include/drm/drm_mipi_dsi.h*/
              dsi,mode-flags = <0x805>; /*MIPI_DSI_MODE_VIDEO*/
              clocks = <&si5351a 0>;
              status = "okay";
        };

The above configurations can be useless in some cases and prevent the panel from turning on.
This is due to the i.MX8 DSI video driver that recalculates the panel timing to adapt them to the i.MX8 DSI video output. In these cases, a fine tuning in the admitted panel timing is necessary: clocks, front and back porch until the LVDS panel turns on.