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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> | ||