VGA(4) BSD Kernel Interfaces Manual VGA(4)NAMEvga — generic video card interface
SYNOPSIS
options VESA
options VESA_DEBUG=N
options VGA_ALT_SEQACCESS
options VGA_NO_FONT_LOADING
options VGA_NO_MODE_CHANGE
options VGA_SLOW_IOACCESS
options VGA_WIDTH90
device vga
In /boot/device.hints:
hint.vga.0.at="isa"
DESCRIPTION
The vga driver is a generic video card driver which provides access to
video cards. This driver is required for the console driver syscons(4).
The console driver will call the vga driver to manipulate video hardware
(changing video modes, loading font, etc).
The vga driver supports the standard video cards: MDA, CGA, EGA and VGA.
In addition, the driver can utilize VESA BIOS extensions if the video
card supports them. VESA support can either be statically included in
the kernel or can be loaded as a separate module.
In order to statically link the VESA support to the kernel, the VESA
option (see below) must be defined in the kernel configuration file.
The vesa module can be dynamically loaded into the kernel using
kldload(8).
DRIVER CONFIGURATION
Kernel Configuration Options
The following kernel configuration options (see config(8)) can be used to
control the vga driver. These options provide compatibility with certain
VGA cards.
VGA_ALT_SEQACCESS
You may want to try this option if the mouse pointer is not drawn
correctly or the font does not seem to be loaded properly on the
VGA card. However, it may cause flicker on some systems.
VGA_SLOW_IOACCESS
Older VGA cards may require this option for proper operation. It
makes the driver perform byte-wide I/O to VGA registers and slow
down a little.
VGA_WIDTH90
This option enables 90 column modes: 90x25, 90x30, 90x43, 90x50,
90x60. These modes are not always supported by the video card and
the display. It is highly likely that LCD display cannot work
with these modes.
The following options add optional features to the driver.
VESA Add VESA BIOS support to the driver. If the VGA card has the VESA
BIOS extension 1.2 or later, this option will utilize the VESA
BIOS service to switch to high resolution modes.
VESA_DEBUG=N
Set the VESA support debug level to N. The default value is zero,
which suppresses all debugging output.
The following options will remove some features from the vga driver and
save kernel memory.
VGA_NO_FONT_LOADING
The vga driver can load software font to EGA and VGA cards. This
option removes this feature. Note that if you use this option and
still wish to use the mouse on the console then you must also use
the SC_ALT_MOUSE_IMAGE option. See syscons(4).
VGA_NO_MODE_CHANGE
This option prevents the driver from changing video modes.
EXAMPLES
Your kernel configuration should normally have:
device vga
And you need the following line in /boot/device.hints.
hint.vga.0.at="isa"
The following lines should be included in the kernel configuration file
in order to enable the VESA BIOS Extension support.
options VESA
device vga
If you do not want VESA support included in the kernel, but want to use
occasionally, do not add the VESA option. And load the vesa module as
desired:
kldload vesa
SEE ALSOvgl(3), syscons(4), config(8), kldload(8), kldunload(8)STANDARDS
Video Electronics Standards Association, VESA BIOS Extension (VBE).
HISTORY
The vga driver first appeared in FreeBSD 3.1.
AUTHORS
The vga driver was written by Søren Schmidt ⟨sos@FreeBSD.org⟩ and
Kazutaka Yokota ⟨yokota@FreeBSD.org⟩. This manual page was written by
Kazutaka Yokota.
BSD June 30, 1999 BSD
