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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:02 EST.

1	
2		arkfb - fbdev driver for ARK Logic chips
3		========================================
4	
5	
6	Supported Hardware
7	==================
8	
9		ARK 2000PV chip
10		ICS 5342 ramdac
11	
12		- only BIOS initialized VGA devices supported
13		- probably not working on big endian
14	
15	
16	Supported Features
17	==================
18	
19		*  4 bpp pseudocolor modes (with 18bit palette, two variants)
20		*  8 bpp pseudocolor mode (with 18bit palette)
21		* 16 bpp truecolor modes (RGB 555 and RGB 565)
22		* 24 bpp truecolor mode (RGB 888)
23		* 32 bpp truecolor mode (RGB 888)
24		* text mode (activated by bpp = 0)
25		* doublescan mode variant (not available in text mode)
26		* panning in both directions
27		* suspend/resume support
28	
29	Text mode is supported even in higher resolutions, but there is limitation to
30	lower pixclocks (i got maximum about 70 MHz, it is dependent on specific
31	hardware). This limitation is not enforced by driver. Text mode supports 8bit
32	wide fonts only (hardware limitation) and 16bit tall fonts (driver
33	limitation). Unfortunately character attributes (like color) in text mode are
34	broken for unknown reason, so its usefulness is limited.
35	
36	There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
37	packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
38	with interleaved planes (1 byte interleave), MSB first. Both modes support
39	8bit wide fonts only (driver limitation).
40	
41	Suspend/resume works on systems that initialize video card during resume and
42	if device is active (for example used by fbcon).
43	
44	
45	Missing Features
46	================
47	(alias TODO list)
48	
49		* secondary (not initialized by BIOS) device support
50	   	* big endian support
51		* DPMS support
52		* MMIO support
53		* interlaced mode variant
54		* support for fontwidths != 8 in 4 bpp modes
55		* support for fontheight != 16 in text mode
56		* hardware cursor
57		* vsync synchronization
58		* feature connector support
59		* acceleration support (8514-like 2D)
60	
61	
62	Known bugs
63	==========
64	
65		* character attributes (and cursor) in text mode are broken
66	
67	--
68	Ondrej Zajicek <santiago@crfreenet.org>
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