xref: /freebsd/share/man/man4/vga.4 (revision c30797873f663df5fc45ba0db943393f611bd24e)
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2.\" Copyright (c) 1999
3.\" Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
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27.\" $FreeBSD$
28.\"
29.Dd June 30, 1999
30.Dt VGA 4
31.Os
32.Sh NAME
33.Nm vga
34.Nd generic video card interface
35.Sh SYNOPSIS
36.Cd "options VESA"
37.Cd "options VESA_DEBUG=N"
38.Cd "options VGA_ALT_SEQACCESS"
39.Cd "options VGA_NO_FONT_LOADING"
40.Cd "options VGA_NO_MODE_CHANGE"
41.Cd "options VGA_SLOW_IOACCESS"
42.Cd "options VGA_WIDTH90"
43.Cd "device vga"
44.Pp
45In
46.Pa /boot/device.hints :
47.Cd hint.vga.0.at="isa"
48.Sh DESCRIPTION
49The
50.Nm
51driver is a generic video card driver which provides access to
52video cards.
53This driver is required for the console driver
54.Xr syscons 4 .
55The console driver will call the
56.Nm
57driver to manipulate video hardware (changing video modes, loading font, etc).
58.Pp
59The
60.Nm
61driver supports the standard video cards: MDA, CGA, EGA and VGA.
62In
63addition, the driver can utilize VESA BIOS extensions if the video card
64supports them.
65VESA support can either be statically included in the kernel
66or can be loaded as a separate module.
67.Pp
68In order to statically link the VESA support to the kernel, the
69.Dv VESA
70option (see below) must be defined in the kernel configuration file.
71.Pp
72The
73.Nm vesa
74module can be dynamically loaded into the kernel using
75.Xr kldload 8 .
76.Sh DRIVER CONFIGURATION
77.Ss Kernel Configuration Options
78The following kernel configuration options
79(see
80.Xr config 8 )
81can be used to control the
82.Nm
83driver.
84These options provide compatibility with certain VGA cards.
85.Bl -tag -width MOUSE
86.It Dv VGA_ALT_SEQACCESS
87You may want to try this option if the mouse pointer is not drawn correctly
88or the font does not seem to be loaded properly on the VGA card.
89However, it may cause flicker on some systems.
90.It Dv VGA_SLOW_IOACCESS
91Older VGA cards may require this option for proper operation.
92It makes the driver perform byte-wide I/O to VGA registers and
93slow down a little.
94.It Dv VGA_WIDTH90
95This option enables 90 column modes: 90x25, 90x30, 90x43, 90x50, 90x60.
96These modes are not always supported by the video card and the display.
97It is highly likely that LCD display cannot work with these modes.
98.El
99.Pp
100The following options add optional features to the driver.
101.Bl -tag -width MOUSE
102.It Dv VESA
103Add VESA BIOS support to the driver.
104If the VGA card has the VESA BIOS extension 1.2 or later,
105this option will utilize the VESA BIOS service to switch to high
106resolution modes.
107.It Dv VESA_DEBUG=N
108Set the VESA support debug level to
109.Fa N .
110The default value is zero, which suppresses all debugging output.
111.El
112.Pp
113The following options will remove some features from the
114.Nm
115driver and save kernel memory.
116.Bl -tag -width MOUSE
117.It Dv VGA_NO_FONT_LOADING
118The
119.Nm
120driver can load software font to EGA and VGA cards.
121This option removes this feature.
122Note that if you use this option and
123still wish to use the mouse on the console then you must also use the
124.Dv SC_ALT_MOUSE_IMAGE
125option.
126See
127.Xr syscons 4 .
128.It Dv VGA_NO_MODE_CHANGE
129This option prevents the driver from changing video modes.
130.El
131.\".Sh FILES
132.Sh EXAMPLES
133Your kernel configuration should normally have:
134.Pp
135.Dl "device vga"
136.Pp
137And you need the following line in
138.Pa /boot/device.hints .
139.Pp
140.Dl hint.vga.0.at="isa"
141.Pp
142The following lines should be included in the kernel configuration file
143in order to enable the VESA BIOS Extension support.
144.Pp
145.Dl "options VESA"
146.Dl "device vga"
147.Pp
148If you do not want VESA support included in the kernel, but
149want to use occasionally, do not add the
150.Dv VESA
151option.
152And load the
153.Nm vesa
154module as desired:
155.Pp
156.Dl kldload vesa
157.\".Sh DIAGNOSTICS
158.\".Sh CAVEATS
159.\".Sh BUGS
160.Sh SEE ALSO
161.Xr vgl 3 ,
162.Xr syscons 4 ,
163.Xr config 8 ,
164.Xr kldload 8 ,
165.Xr kldunload 8
166.Sh STANDARDS
167.Rs
168.%T "VESA BIOS Extension (VBE)"
169.%A Video Electronics Standards Association
170.Re
171.Sh HISTORY
172The
173.Nm
174driver first appeared in
175.Fx 3.1 .
176.Sh AUTHORS
177.An -nosplit
178The
179.Nm
180driver was written by
181.An S\(/oren Schmidt Aq Mt sos@FreeBSD.org
182and
183.An Kazutaka Yokota Aq Mt yokota@FreeBSD.org .
184This manual page was written by
185.An Kazutaka Yokota .
186