avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/doc/README.video

@@ -0,0 +1,78 @@
+/*
+ * (C) Copyright 2000
+ * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+"video-mode" environment variable
+=================================
+
+The 'video-mode' environment variable can be used to enable and configure
+some video drivers.  The format matches the video= command-line option used
+for Linux:
+
+	video-mode=<driver>:<xres>x<yres>-<depth>@<freq><,option=string>
+
+	<driver>	The video driver name, ignored by U-Boot
+	<xres>		The X resolution (in pixels) to use.
+	<yres>		The Y resolution (in pixels) to use.
+	<depth>		The color depth (in bits) to use.
+	<freq>		The frequency (in Hz) to use.
+	<options>	A comma-separated list of device-specific options
+
+
+U-Boot MPC8xx video controller driver
+=====================================
+
+The driver has been tested with the following configurations:
+
+- MPC823FADS with AD7176 on a PAL TV (YCbYCr)	- arsenio@tin.it
+
+Example: video-mode=fslfb:1280x1024-32@60,monitor=dvi
+
+
+U-Boot sunxi video controller driver
+====================================
+
+U-Boot supports hdmi and lcd output on Allwinner sunxi SoCs, lcd output
+requires the CONFIG_VIDEO_LCD_MODE Kconfig value to be set.
+
+The sunxi U-Boot driver supports the following video-mode options:
+
+- monitor=[none|dvi|hdmi|lcd|vga|composite-*] - Select the video output to use
+ none:     Disable video output.
+ dvi/hdmi: Selects output over the hdmi connector with dvi resp. hdmi output
+           format, if edid is used the format is automatically selected.
+ lcd:      Selects video output to a LCD screen.
+ vga:      Selects video output over the VGA connector.
+ composite-pal/composite-ntsc/composite-pal-m/composite-pal-nc:
+           Selects composite video output, note the specified resolution is
+           ignored with composite video output.
+ Defaults to monitor=dvi.
+
+- hpd=[0|1] - Enable use of the hdmi HotPlug Detect feature
+ 0: Disabled. Configure dvi/hdmi output even if no cable is detected
+ 1: Enabled.  Fallback to the lcd / vga / none in that order (if available)
+ Defaults to hpd=1.
+
+- hpd_delay=<int> - How long to wait for the hdmi HPD signal in milliseconds
+ When the monitor and the board power up at the same time, it may take some
+ time for the monitor to assert the HPD signal. This configures how long to
+ wait for the HPD signal before assuming no cable is connected.
+ Defaults to hpd_delay=500.
+
+- edid=[0|1] - Enable use of DDC + EDID to get monitor info
+ 0: Disabled.
+ 1: Enabled. If valid EDID info was read from the monitor the EDID info will
+    overrides the xres, yres and refresh from the video-mode env. variable.
+ Defaults to edid=1.
+
+- overscan_x/overscan_y=<int> - Set x/y overscan value
+ This configures a black border on the left and right resp. top and bottom
+ to deal with overscanning displays. Defaults to overscan_x=32 and
+ overscan_y=20 for composite monitors, 0 for other monitors.
+
+For example to always use the hdmi connector, even if no cable is inserted,
+using edid info when available and otherwise initalizing it at 1024x768@60Hz,
+use: "setenv video-mode sunxi:1024x768-24@60,monitor=dvi,hpd=0,edid=1".