blob: fd68b162e4a13ce7cbf028405a14724224542e1f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001Intel 810/815 Framebuffer driver
2 Tony Daplas <adaplas@pol.net>
3 http://i810fb.sourceforge.net
4
5 March 17, 2002
6
7 First Released: July 2001
8================================================================
9
10A. Introduction
11 This is a framebuffer driver for various Intel 810/815 compatible
12graphics devices. These would include:
13
14 Intel 810
15 Intel 810E
16 Intel 810-DC100
17 Intel 815 Internal graphics only, 100Mhz FSB
18 Intel 815 Internal graphics only
19 Intel 815 Internal graphics and AGP
20
21B. Features
22
23 - Choice of using Discrete Video Timings, VESA Generalized Timing
24 Formula, or a framebuffer specific database to set the video mode
25
26 - Supports a variable range of horizontal and vertical resolution, and
27 vertical refresh rates if the VESA Generalized Timing Formula is
28 enabled.
29
30 - Supports color depths of 8, 16, 24 and 32 bits per pixel
31
32 - Supports pseudocolor, directcolor, or truecolor visuals
33
34 - Full and optimized hardware acceleration at 8, 16 and 24 bpp
35
36 - Robust video state save and restore
37
38 - MTRR support
39
40 - Utilizes user-entered monitor specifications to automatically
41 calculate required video mode parameters.
42
43 - Can concurrently run with xfree86 running with native i810 drivers
44
45 - Hardware Cursor Support
46
47C. List of available options
48
49 a. "video=i810fb"
50 enables the i810 driver
51
52 Recommendation: required
53
54 b. "xres:<value>"
55 select horizontal resolution in pixels
56
57 Recommendation: user preference
58 (default = 640)
59
60 c. "yres:<value>"
61 select vertical resolution in scanlines. If Discrete Video Timings
62 is enabled, this will be ignored and computed as 3*xres/4.
63
64 Recommendation: user preference
65 (default = 480)
66
67 d. "vyres:<value>"
68 select virtual vertical resolution in scanlines. If (0) or none
69 is specified, this will be computed against maximum available memory.
70
71 Recommendation: do not set
72 (default = 480)
73
74 e. "vram:<value>"
75 select amount of system RAM in MB to allocate for the video memory
76
77 Recommendation: 1 - 4 MB.
78 (default = 4)
79
80 f. "bpp:<value>"
81 select desired pixel depth
82
83 Recommendation: 8
84 (default = 8)
85
86 g. "hsync1/hsync2:<value>"
87 select the minimum and maximum Horizontal Sync Frequency of the
88 monitor in KHz. If a using a fixed frequency monitor, hsync1 must
89 be equal to hsync2.
90
91 Recommendation: check monitor manual for correct values
92 default (29/30)
93
94 h. "vsync1/vsync2:<value>"
95 select the minimum and maximum Vertical Sync Frequency of the monitor
96 in Hz. You can also use this option to lock your monitor's refresh
97 rate.
98
99 Recommendation: check monitor manual for correct values
100 (default = 60/60)
101
102 IMPORTANT: If you need to clamp your timings, try to give some
103 leeway for computational errors (over/underflows). Example: if
104 using vsync1/vsync2 = 60/60, make sure hsync1/hsync2 has at least
105 a 1 unit difference, and vice versa.
106
107 i. "voffset:<value>"
108 select at what offset in MB of the logical memory to allocate the
109 framebuffer memory. The intent is to avoid the memory blocks
110 used by standard graphics applications (XFree86). The default
111 offset (16 MB for a 64MB aperture, 8 MB for a 32MB aperture) will
112 avoid XFree86's usage and allows up to 7MB/15MB of framebuffer
113 memory. Depending on your usage, adjust the value up or down,
114 (0 for maximum usage, 31/63 MB for the least amount). Note, an
115 arbitrary setting may conflict with XFree86.
116
117 Recommendation: do not set
118 (default = 8 or 16 MB)
119
120 j. "accel"
121 enable text acceleration. This can be enabled/reenabled anytime
122 by using 'fbset -accel true/false'.
123
124 Recommendation: enable
125 (default = not set)
126
127 k. "mtrr"
128 enable MTRR. This allows data transfers to the framebuffer memory
129 to occur in bursts which can significantly increase performance.
130 Not very helpful with the i810/i815 because of 'shared memory'.
131
132 Recommendation: do not set
133 (default = not set)
134
135 l. "extvga"
136 if specified, secondary/external VGA output will always be enabled.
137 Useful if the BIOS turns off the VGA port when no monitor is attached.
138 The external VGA monitor can then be attached without rebooting.
139
140 Recommendation: do not set
141 (default = not set)
142
143 m. "sync"
144 Forces the hardware engine to do a "sync" or wait for the hardware
145 to finish before starting another instruction. This will produce a
146 more stable setup, but will be slower.
147
148 Recommendation: do not set
149 (default = not set)
150
151 n. "dcolor"
152 Use directcolor visual instead of truecolor for pixel depths greater
153 than 8 bpp. Useful for color tuning, such as gamma control.
154
155 Recommendation: do not set
156 (default = not set)
157
158D. Kernel booting
159
160Separate each option/option-pair by commas (,) and the option from its value
161with a colon (:) as in the following:
162
163video=i810fb:option1,option2:value2
164
165Sample Usage
166------------
167
168In /etc/lilo.conf, add the line:
169
170append="video=i810fb:vram:2,xres:1024,yres:768,bpp:8,hsync1:30,hsync2:55, \
171 vsync1:50,vsync2:85,accel,mtrr"
172
173This will initialize the framebuffer to 1024x768 at 8bpp. The framebuffer
174will use 2 MB of System RAM. MTRR support will be enabled. The refresh rate
175will be computed based on the hsync1/hsync2 and vsync1/vsync2 values.
176
177IMPORTANT:
178You must include hsync1, hsync2, vsync1 and vsync2 to enable video modes
179better than 640x480 at 60Hz.
180
181E. Module options
182
183 The module parameters are essentially similar to the kernel
184parameters. The main difference is that you need to include a Boolean value
185(1 for TRUE, and 0 for FALSE) for those options which don't need a value.
186
187Example, to enable MTRR, include "mtrr=1".
188
189Sample Usage
190------------
191
192Using the same setup as described above, load the module like this:
193
194 modprobe i810fb vram=2 xres=1024 bpp=8 hsync1=30 hsync2=55 vsync1=50 \
195 vsync2=85 accel=1 mtrr=1
196
197Or just add the following to /etc/modprobe.conf
198
199 options i810fb vram=2 xres=1024 bpp=16 hsync1=30 hsync2=55 vsync1=50 \
200 vsync2=85 accel=1 mtrr=1
201
202and just do a
203
204 modprobe i810fb
205
206
207F. Setup
208
209 a. Do your usual method of configuring the kernel.
210
211 make menuconfig/xconfig/config
212
213 b. Under "Code Maturity Options", enable "Prompt for experimental/
214 incomplete code/drivers".
215
216 c. Enable agpgart support for the Intel 810/815 on-board graphics.
217 This is required. The option is under "Character Devices"
218
219 d. Under "Graphics Support", select "Intel 810/815" either statically
220 or as a module. Choose "use VESA GTF for video timings" if you
221 need to maximize the capability of your display. To be on the
222 safe side, you can leave this unselected.
223
224 e. If you want a framebuffer console, enable it under "Console
225 Drivers"
226
227 f. Compile your kernel.
228
229 g. Load the driver as described in section D and E.
230
231 Optional:
232 h. If you are going to run XFree86 with its native drivers, the
233 standard XFree86 4.1.0 and 4.2.0 drivers should work as is.
234 However, there's a bug in the XFree86 i810 drivers. It attempts
235 to use XAA even when switched to the console. This will crash
236 your server. I have a fix at this site:
237
238 http://i810fb.sourceforge.net.
239
240 You can either use the patch, or just replace
241
242 /usr/X11R6/lib/modules/drivers/i810_drv.o
243
244 with the one provided at the website.
245
246 i. Try the DirectFB (http://www.directfb.org) + the i810 gfxdriver
247 patch to see the chipset in action (or inaction :-).
248
249G. Acknowledgment:
250
251 1. Geert Uytterhoeven - his excellent howto and the virtual
252 framebuffer driver code made this possible.
253
254 2. Jeff Hartmann for his agpgart code.
255
256 3. The X developers. Insights were provided just by reading the
257 XFree86 source code.
258
259 4. Intel(c). For this value-oriented chipset driver and for
260 providing documentation.
261
262 5. Matt Sottek. His inputs and ideas helped in making some
263 optimizations possible.
264
265H. Home Page:
266
267 A more complete, and probably updated information is provided at
268http://i810fb.sourceforge.net.
269
270###########################
271Tony
272