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Based on kernel version 3.13. Page generated on 2014-01-20 22:02 EST.

1	
2		vt8623fb - fbdev driver for graphics core in VIA VT8623 chipset
3		===============================================================
4	
5	
6	Supported Hardware
7	==================
8	
9		VIA VT8623 [CLE266] chipset and	its graphics core
10			(known as CastleRock or Unichrome)
11	
12	I tested vt8623fb on VIA EPIA ML-6000
13	
14	
15	Supported Features
16	==================
17	
18		*  4 bpp pseudocolor modes (with 18bit palette, two variants)
19		*  8 bpp pseudocolor mode (with 18bit palette)
20		* 16 bpp truecolor mode (RGB 565)
21		* 32 bpp truecolor mode (RGB 888)
22		* text mode (activated by bpp = 0)
23		* doublescan mode variant (not available in text mode)
24		* panning in both directions
25		* suspend/resume support
26		* DPMS support
27	
28	Text mode is supported even in higher resolutions, but there is limitation to
29	lower pixclocks (maximum about 100 MHz). This limitation is not enforced by
30	driver. Text mode supports 8bit wide fonts only (hardware limitation) and
31	16bit tall fonts (driver limitation).
32	
33	There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
34	packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
35	with interleaved planes (1 byte interleave), MSB first. Both modes support
36	8bit wide fonts only (driver limitation).
37	
38	Suspend/resume works on systems that initialize video card during resume and
39	if device is active (for example used by fbcon).
40	
41	
42	Missing Features
43	================
44	(alias TODO list)
45	
46		* secondary (not initialized by BIOS) device support
47		* MMIO support
48		* interlaced mode variant
49		* support for fontwidths != 8 in 4 bpp modes
50		* support for fontheight != 16 in text mode
51		* hardware cursor
52		* video overlay support
53		* vsync synchronization
54		* acceleration support (8514-like 2D, busmaster transfers)
55	
56	
57	Known bugs
58	==========
59	
60		* cursor disable in text mode doesn't work
61	
62	
63	--
64	Ondrej Zajicek <santiago@crfreenet.org>
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