xref: /OK3568_Linux_fs/kernel/Documentation/fb/tgafb.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun==============
2*4882a593SmuzhiyunWhat is tgafb?
3*4882a593Smuzhiyun==============
4*4882a593Smuzhiyun
5*4882a593SmuzhiyunThis is a driver for DECChip 21030 based graphics framebuffers, a.k.a. TGA
6*4882a593Smuzhiyuncards, which are usually found in older Digital Alpha systems. The
7*4882a593Smuzhiyunfollowing models are supported:
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun- ZLxP-E1 (8bpp, 2 MB VRAM)
10*4882a593Smuzhiyun- ZLxP-E2 (32bpp, 8 MB VRAM)
11*4882a593Smuzhiyun- ZLxP-E3 (32bpp, 16 MB VRAM, Zbuffer)
12*4882a593Smuzhiyun
13*4882a593SmuzhiyunThis version is an almost complete rewrite of the code written by Geert
14*4882a593SmuzhiyunUytterhoeven, which was based on the original TGA console code written by
15*4882a593SmuzhiyunJay Estabrook.
16*4882a593Smuzhiyun
17*4882a593SmuzhiyunMajor new features since Linux 2.0.x:
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun * Support for multiple resolutions
20*4882a593Smuzhiyun * Support for fixed-frequency and other oddball monitors
21*4882a593Smuzhiyun   (by allowing the video mode to be set at boot time)
22*4882a593Smuzhiyun
23*4882a593SmuzhiyunUser-visible changes since Linux 2.2.x:
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun * Sync-on-green is now handled properly
26*4882a593Smuzhiyun * More useful information is printed on bootup
27*4882a593Smuzhiyun   (this helps if people run into problems)
28*4882a593Smuzhiyun
29*4882a593SmuzhiyunThis driver does not (yet) support the TGA2 family of framebuffers, so the
30*4882a593SmuzhiyunPowerStorm 3D30/4D20 (also known as PBXGB) cards are not supported. These
31*4882a593Smuzhiyuncan however be used with the standard VGA Text Console driver.
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun
34*4882a593SmuzhiyunConfiguration
35*4882a593Smuzhiyun=============
36*4882a593Smuzhiyun
37*4882a593SmuzhiyunYou can pass kernel command line options to tgafb with
38*4882a593Smuzhiyun`video=tgafb:option1,option2:value2,option3` (multiple options should be
39*4882a593Smuzhiyunseparated by comma, values are separated from options by `:`).
40*4882a593Smuzhiyun
41*4882a593SmuzhiyunAccepted options:
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun==========  ============================================================
44*4882a593Smuzhiyunfont:X      default font to use. All fonts are supported, including the
45*4882a593Smuzhiyun	    SUN12x22 font which is very nice at high resolutions.
46*4882a593Smuzhiyun
47*4882a593Smuzhiyunmode:X      default video mode. The following video modes are supported:
48*4882a593Smuzhiyun	    640x480-60, 800x600-56, 640x480-72, 800x600-60, 800x600-72,
49*4882a593Smuzhiyun	    1024x768-60, 1152x864-60, 1024x768-70, 1024x768-76,
50*4882a593Smuzhiyun	    1152x864-70, 1280x1024-61, 1024x768-85, 1280x1024-70,
51*4882a593Smuzhiyun	    1152x864-84, 1280x1024-76, 1280x1024-85
52*4882a593Smuzhiyun==========  ============================================================
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun
55*4882a593SmuzhiyunKnown Issues
56*4882a593Smuzhiyun============
57*4882a593Smuzhiyun
58*4882a593SmuzhiyunThe XFree86 FBDev server has been reported not to work, since tgafb doesn't do
59*4882a593Smuzhiyunmmap(). Running the standard XF86_TGA server from XFree86 3.3.x works fine for
60*4882a593Smuzhiyunme, however this server does not do acceleration, which make certain operations
61*4882a593Smuzhiyunquite slow. Support for acceleration is being progressively integrated in
62*4882a593SmuzhiyunXFree86 4.x.
63*4882a593Smuzhiyun
64*4882a593SmuzhiyunWhen running tgafb in resolutions higher than 640x480, on switching VCs from
65*4882a593Smuzhiyuntgafb to XF86_TGA 3.3.x, the entire screen is not re-drawn and must be manually
66*4882a593Smuzhiyunrefreshed. This is an X server problem, not a tgafb problem, and is fixed in
67*4882a593SmuzhiyunXFree86 4.0.
68*4882a593Smuzhiyun
69*4882a593SmuzhiyunEnjoy!
70*4882a593Smuzhiyun
71*4882a593SmuzhiyunMartin Lucina <mato@kotelna.sk>
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