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Based on kernel version 3.16. Page generated on 2014-08-06 21:39 EST.

1	Tridentfb is a framebuffer driver for some Trident chip based cards.
2	
3	The following list of chips is thought to be supported although not all are
4	tested:
5	
6	those from the TGUI series 9440/96XX and with Cyber in their names
7	those from the Image series and with Cyber in their names
8	those with Blade in their names (Blade3D,CyberBlade...)
9	the newer CyberBladeXP family
10	
11	All families are accelerated. Only PCI/AGP based cards are supported,
12	none of the older Tridents.
13	The driver supports 8, 16 and 32 bits per pixel depths.
14	The TGUI family requires a line length to be power of 2 if acceleration
15	is enabled. This means that range of possible resolutions and bpp is
16	limited comparing to the range if acceleration is disabled (see list
17	of parameters below).
18	
19	Known bugs:
20	1. The driver randomly locks up on 3DImage975 chip with acceleration
21	   enabled. The same happens in X11 (Xorg).
22	2. The ramdac speeds require some more fine tuning. It is possible to
23	   switch resolution which the chip does not support at some depths for
24	   older chips.
25	
26	How to use it?
27	==============
28	
29	When booting you can pass the video parameter.
30	video=tridentfb
31	
32	The parameters for tridentfb are concatenated with a ':' as in this example.
33	
34	video=tridentfb:800x600-16@75,noaccel
35	
36	The second level parameters that tridentfb understands are:
37	
38	noaccel - turns off acceleration (when it doesn't work for your card)
39	
40	fp	- use flat panel related stuff
41	crt 	- assume monitor is present instead of fp
42	
43	center 	- for flat panels and resolutions smaller than native size center the
44		  image, otherwise use
45	stretch
46	
47	memsize - integer value in KB, use if your card's memory size is misdetected.
48		  look at the driver output to see what it says when initializing.
49	
50	memdiff - integer value in KB, should be nonzero if your card reports
51		  more memory than it actually has. For instance mine is 192K less than
52		  detection says in all three BIOS selectable situations 2M, 4M, 8M.
53		  Only use if your video memory is taken from main memory hence of
54		  configurable size. Otherwise use memsize.
55		  If in some modes which barely fit the memory you see garbage
56		  at the bottom this might help by not letting change to that mode
57		  anymore.
58	
59	nativex - the width in pixels of the flat panel.If you know it (usually 1024
60		  800 or 1280) and it is not what the driver seems to detect use it.
61	
62	bpp	- bits per pixel (8,16 or 32)
63	mode	- a mode name like 800x600-8@75 as described in
64		  Documentation/fb/modedb.txt
65	
66	Using insane values for the above parameters will probably result in driver
67	misbehaviour so take care(for instance memsize=12345678 or memdiff=23784 or
68	nativex=93)
69	
70	Contact: jani@astechnix.ro
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