mirror of
				https://xff.cz/git/u-boot/
				synced 2025-10-30 18:05:48 +01:00 
			
		
		
		
	Correct spelling of "U-Boot" shall be used in all written text (documentation, comments in source files etc.). Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Heiko Schocher <hs@denx.de> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>
		
			
				
	
	
		
			79 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| /*
 | |
|  * (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".
 |