|VGA(4)||Device Drivers Manual||VGA(4)|
vgadriver 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
vgadriver to manipulate video hardware (changing video modes, loading font, etc).
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.
vesa module can be dynamically loaded
into the kernel using kldload(8).
Kernel Configuration Options¶The following kernel configuration options (see config(8)) can be used to control the
vgadriver. These options provide compatibility with certain VGA cards.
- 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.
- 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.
- 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.
- 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.
- 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.
vgadriver 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_IMAGEoption. See syscons(4).
- This option prevents the driver from changing video modes.
EXAMPLES¶Your kernel configuration should normally have:
And you need the following line in /boot/device.hints.
The following lines should be included in the kernel configuration file in order to enable the VESA BIOS Extension support.
If you do not want VESA support included in the kernel, but want
to use occasionally, do not add the
VESA option. And
vesa module as desired:
SEE ALSO¶vgl(3), syscons(4), config(8), kldload(8), kldunload(8)
STANDARDS¶Video Electronics Standards Association, VESA BIOS Extension (VBE).
vgadriver first appeared in FreeBSD 3.1.
vgadriver was written by Søren Schmidt <sos@FreeBSD.org> and Kazutaka Yokota <yokota@FreeBSD.org>. This manual page was written by Kazutaka Yokota.
|June 30, 1999||Linux 4.9.0-9-amd64|