1Plex86/Bochs VGABios
2--------------------
3
4The goal of this project is to have a LGPL'd Video Bios in plex86,
5Bochs and qemu.
6This VGA Bios is very specific to the emulated VGA card.
7It is NOT meant to drive a physical vga card.
8
9
10Cirrus SVGA extension
11---------------------
12
13The Cirrus SVGA extension is designed for the Cirrus emulation in Bochs and
14qemu. The initial patch for the Cirrus extension has been written by Makoto
15Suzuki (suzu).
16
17
18Install
19-------
20To compile the VGA Bios you will need :
21- gcc
22- bcc
23- as86
24- ld86
25
26Untar the archive, and type make. You should get a "VGABIOS-lgpl-latest.bin"
27file. Alternatively, you can use the binary file "VGABIOS-lgpl-latest.bin",
28i have compiled for you.
29
30Edit your plex86/bochs conf file, and modify the load-rom command in the
31VGA BIOS section, to point to the new vgabios image file.
32
33
34Debugging
35---------
36You can get a very basic debugging system: messages printed by the vgabios.
37You have to register the "unmapped" device driver in plex86 or bochs, and make
38sure it grabs port 0xfff0.
39
40Comment the #undef DEBUG at the beginning of vgabios.c.
41You can then use the "printf" function in the bios.
42
43
44Testing
45-------
46Look at the "testvga.c" file in the archive. This is a minimal Turbo C 2.0
47source file that calls a few int10 functions. Feel free to modify it to suit
48your needs.
49
50
51Copyright and License
52---------------------
53This program has been written by Christophe Bothamy
54It is protected by the GNU Lesser Public License, which you should
55have received a copy of along with this package.
56
57
58Reverse Engineering
59-------------------
60The VGA Bios has been written without reverse-engineering any existing Bios.
61
62
63Acknowledgment
64--------------
65The source code contains code ripped from rombios.c of plex86, written
66by Kevin Lawton <kevin2001@yahoo.com>
67
68The source code contains fonts from fntcol16.zip (c) by Joseph Gil avalable at :
69ftp://ftp.simtel.net/pub/simtelnet/msdos/screen/fntcol16.zip
70These fonts are public domain
71
72The source code is based on information taken from :
73- Kevin Lawton's vga card emulation for bochs/plex86
74- Ralf Brown's interrupts list avalaible at
75 http://www.cs.cmu.edu/afs/cs/user/ralf/pub/WWW/files.html
76- Finn Thogersons' VGADOC4b available at http://home.worldonline.dk/~finth/
77- Michael Abrash's Graphics Programming Black Book
78- Francois Gervais' book "programmation des cartes graphiques cga-ega-vga"
79 edited by sybex
80- DOSEMU 1.0.1 source code for several tables values and formulas
81
82
83Feedback
84--------
85Please report any bugs, comments, patches for this VGA Bios to info@vruppert.de
86You can find the latest release at : http://www.nongnu.org/vgabios/
87For any information on bochs, visit the website http://bochs.sourceforge.net/
88For any information on qemu, visit the website http://fabrice.bellard.free.fr/qemu/
89
90
91History
92-------
93vgabios-0.6c : Apr 08 2009
94 - Volker
95 . added DPMS support to cirrus vgabios (patch from Gleb Natapov)
96 . use VBE LFB address from PCI base address if present
97 . added support for a lot more non-standard VBE modes (e.g. widescreen modes)
98 . minor bugfixes
99
100vgabios-0.6b : May 30 2008
101 - Volker
102 . added PCI data structure for the Cirrus VGABIOS images
103 . minor bugfixes in biossums utility, VBE support and makefile
104
105vgabios-0.6a : Aug 19 2006
106 - Volker
107 . added minimal support for the video parameter table (VPT)
108 . Cirrus SVGA now supports the "no clear" bit in Cirrus and VESA mode
109 . Bochs VBE protected mode interface improved
110 . save/restore video state support for Bochs VBE and standard VGA added
111 . generate vbetables.h dynamicly
112 . VBE video memory increased to 8 MB (VBE dispi ID changed to B0C4)
113 . lots of 4bpp VBE fixes (all 4bpp VBE modes now enabled)
114 . VGA compatible setup for VBE modes added
115
116vgabios-0.5d : Dec 29 2005
117 - Volker
118 . Bochs VBE protected mode interface added (based on a patch by malc@pulsesoft.com)
119 . biossums utility now supports VGABIOS sizes up to 64 kBytes
120 . VGA mode 0x11: all color planes must be enabled in this 2-color VGA mode
121
122vgabios-0.5c : Jul 07 2005
123 - Volker
124 . BIOS configuration word usually reports initial mode 80x25 color text
125 . vgabios function 0x0e (write teletype): linefeed (0x0a) only increments the
126 cursor row value
127
128vgabios-0.5b : May 24 2005
129 - Volker
130 . fixed return value for the default case in the VBE section (non-debug mode)
131 . removed unused stuff
132
133vgabios-0.5a : Mar 07 2005
134 - Volker
135 . Cirrus SVGA extension (initial patches from Makoto Suzuki, improvements
136 from Fabrice Bellard)
137 . vgabios image size is now exactly 32k with a checksum
138 . a lot of vgabios and vbe functions rewritten in assembler
139 . dynamicly generated VBE mode info list
140 . write character function for CGA and LINEAR8 modes
141 . read/write graphics pixel for some graphics modes
142 . text scroll feature for some graphics modes
143 . VBE 8-bit DAC support
144
145vgabios-0.4c : Nov 06 2003
146 - Christophe
147 . fix font problem on initial screen of NT4 Loader
148
149vgabios-0.4b : Nov 04 2003
150 - Volker
151 . fix offset of character tables
152 . optimizations of CRT controller accesses
153 . VBE i/o registers changed to 0x01CE/CF
154 (suggestion from Daniel Gimpelevich)
155 . "noclear" flag stored in BIOS area
156 . fix character height returned by get_font_info function
157
158vgabios-0.4a : Aug 17 2003
159 - Volker
160 . VBE mode search rewritten (VBE modes with LFB bit removed)
161 . many bugfixes and optimizations
162 . write character function implemented for graphics modes
163 . support for 15bpp, 16bpp, 24bpp and 32bpp VBE modes added
164 . SVGA mode 0x6A added
165 . VBE modes 0x102, 0x117, 0x118 and 0x142 (Bochs specific)
166
167vgabios-0.3b : Nov 23 2002
168 - Christophe
169 . added lfb-mode numbers (patch from mathis)
170 . updated the Makefile
171 . removed display of copyrights.
172 . changed the Copyright string to "LGPL VGABios developers"
173 - Volker
174 . set the cursor shape depending on the current font height
175 . clear BL before calling int 0x10 function 0x1103 in vgabios_init_func
176 . added some text font functions
177 - Jeroen
178 . Forced to new DISPI (0xb0c1) interface (requires latest bochs vbe code)
179 . Added multibuffering support
180 . Added new DISPI interface for: virt width, height, x offset, y offset
181 . Added LFB modes (to be used with the vbe-lfb patch in bochs)
182 see VBE_HAVE_LFB in vbe.c (currently default enabled)
183 . updated TODO & docs for changes after bochs 1.4
184
185vgabios-0.3a : Mar 10 2002
186 - Christophe
187 . Fixed bug in function ah=13
188 - Jeroen
189 . updated vbebios implementation to new api
190 . added vbe_display_api documentation
191 . added 640x400x8, 640x480x8, 800x600x8, 1024x768
192 (>640x480 needs a special bochs patch atm)
193 . added 320x200x8 vbe support (uses the standard 320x200x8 vga mode to
194 display, this allows for testing & having something on screen as well,
195 at least until bochs host side display is up & running)
196 . adding lfbprof (vbe) testprogram (+some small fixes to it)
197 . merging with vbebios 0.2
198
199vgabios-0.2b : Nov 19 2001
200 - Christophe
201 . Fixed bug in function ah=13
202
203vgabios-0.2a : Nov 09 2001
204 - Christophe
205 . Included bugfix from techt@pikeonline.net about grayscale summing
206 . Added the "IBM" string at org 0x1e as Bart Oldeman suggested
207 . Fixed DS and ES that where inverted in the int10 parameters list!
208 . The following have been implemented :
209 - function ax=1a00, ax=1a01, ah=1b
210 - function ax=1130
211 . Added debug messages for unimplemented/unknown functions
212 Must be compiled with DEBUG defined. The output is trapped
213 by the unknown-ioport driver of plex/bochs (port 0xfff0 is used)
214
215vgabios-0.1a : May 8 2001
216 - Christophe
217 . First release. The work has been focused only on text mode.
218 . The following have been implemented :
219 - inits
220 - int 10 handler
221 - functions ah=00, ah=01, ah=02, ah=03, ah=05, ah=06, ah=07, ah=08
222 ah=09, ah=0a, ah=0e, ah=0f, ax=1000, ax=1001, ax=1002, ax=1003
223 ax=1007, ax=1008, ax=1009, ax=1010, ax=1012, ax=1013, ax=1015
224 ax=1017, ax=1018, ax=1019, ax=101a, ax=101b, ah=12 bl=10,
225 ah=12 bl=30, ah=12 bl=31, ah=12 bl=32, ah=12 bl=33, ah=12 bl=34
226 ah=13
227