1  Information for Alliance Promotion chipset users
2  Loic Grenie ( <mailto:grenie@math.jussieu.fr>), Henrik
3  Harmsen ( <mailto:Henrik.Harmsen@erv.ericsson.se>)
4  6 March 2000
5  ____________________________________________________________
6
7  Table of Contents
8
9
10  1. Support chipsets
11  2. Acceleration
12  3. DGA
13  4. Video
14  5. Shadow framebuffer
15  6. Configuration
16  7. glide2x
17  8. Questions
18
19
20  ______________________________________________________________________
21
22  1.  Support chipsets
23
24  The apm driver in the SVGA server is for Alliance Promotion graphics
25  chipsets. The following chipsets are supported:
26
27
28  o  6422
29
30     Old chipset. The driver is still very unstable and has computer
31     crashes. You should use XFree86 3.3.x for this chipset.
32
33
34  o  AT24
35
36     As found in Diamond Stealth Video 2500. Quite similar to AT3D.
37
38  o  AT25, AT3D
39
40     AT3D is found in Hercules Stingray 128/3D. Most other Voodoo Rush
41     based cards use the AT25 which is identical except it doesn't have
42     the 3D stuff in it.
43
44
45  2.  Acceleration
46
47  The apm driver uses the XAA in the SVGA server. It has support for the
48  following acceleration:
49
50
51  o  Bitblts (rectangle copy operation)
52
53  o  Lines (solid, single pixel)
54
55  o  Filled rectangles
56
57  o  CPU->Screen image transfers.
58
59  o  CPU->Screen colour expansion (text accel).
60
61  o  Screen->Screen colour expansion (cached text accel).
62
63  o  Mono 8x8 pattern fill. Not for 6422.
64
65  o  Colour 8x8 pattern fill (in 8bpp). Not for 6422.
66
67  o  Hardware cursor.
68
69  o  Pixmap caching.
70
71  All in 8, 16 and 32 bpp modes. In 24bpp mode only Bitblts and Filled
72  rectangles is supported. Also VESA DPMS power save mode is fully
73  supported with "standby", "suspend" and "off" modes (set with with the
74  "xset dpms" command).
75
76
77  3.  DGA
78
79  Full DGA 2.0 support with framebuffer access and drawing acceleration.
80
81
82  4.  Video
83
84  It has limited hardware support for video decoding on the AT24 and
85  AT25/3D. It can also display an image in YUV colours inside the
86  desktop. There are some more exotic formats such as YUV 4.1.1, YUV
87  4.0.0 and RGB 8,16.32bpp.
88
89
90  5.  Shadow framebuffer
91
92  There is a mode, called shadow framebuffer, where the graphics are
93  used to display the images. All rendering is done in memory in a so-
94  called shadow framebuffer. This mode is useful if you need lots of
95  reading in the video memory and to use it you will have to put
96
97    Option "ShadowFB"
98
99
100
101  in your xorg.conf file.
102
103
104  6.  Configuration
105
106  You can turn off hardware cursor by inserting the following line in
107  the Device section of the xorg.conf file:
108
109    Option "SWcursor"
110
111
112
113  Or turn off hardware acceleration:
114
115    Option "noaccel"
116
117
118
119  Or turn off MMIO
120
121
122    Option "nolinear"
123
124
125
126  Do not specify either the amount of video RAM or which chipset in the
127  config file. It is better to let the driver probe for this. Also don't
128  put any "clocks" line in the device section since these chips have a
129  fully programmable clock that can almost take any modeline you throw
130  at it. It might though fail at some specific clock values but in that
131  case you should just try a slightly different clock and it should
132  work.
133
134
135  7.  glide2x
136
137  There is support for the XF86Rush extension for use with the glide2x
138  library.
139
140
141  8.  Questions
142
143  Any questions regarding this driver should be sent to Loic Grenie. It
144  should be possible to add support for the 3210 chipset if someone
145  needs it.
146
147
148
149