diff options
Diffstat (limited to 'Documentation/fb')
-rw-r--r-- | Documentation/fb/s3fb.txt | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/Documentation/fb/s3fb.txt b/Documentation/fb/s3fb.txt new file mode 100644 index 000000000000..8a04c0da0c91 --- /dev/null +++ b/Documentation/fb/s3fb.txt | |||
@@ -0,0 +1,78 @@ | |||
1 | |||
2 | s3fb - fbdev driver for S3 Trio/Virge chips | ||
3 | =========================================== | ||
4 | |||
5 | |||
6 | Supported Hardware | ||
7 | ================== | ||
8 | |||
9 | S3 Trio32 | ||
10 | S3 Trio64 (and variants V+, UV+, V2/DX, V2/GX) | ||
11 | S3 Virge (and variants VX, DX, GX and GX2+) | ||
12 | S3 Plato/PX (completely untested) | ||
13 | S3 Aurora64V+ (completely untested) | ||
14 | |||
15 | - only PCI bus supported | ||
16 | - only BIOS initialized VGA devices supported | ||
17 | - probably not working on big endian | ||
18 | |||
19 | I tested s3fb on Trio64 (plain, V+ and V2/DX) and Virge (plain, VX, DX), | ||
20 | all on i386. | ||
21 | |||
22 | |||
23 | Supported Features | ||
24 | ================== | ||
25 | |||
26 | * 4 bpp pseudocolor modes (with 18bit palette, two variants) | ||
27 | * 8 bpp pseudocolor mode (with 18bit palette) | ||
28 | * 16 bpp truecolor modes (RGB 555 and RGB 565) | ||
29 | * 24 bpp truecolor mode (RGB 888) on (only on Virge VX) | ||
30 | * 32 bpp truecolor mode (RGB 888) on (not on Virge VX) | ||
31 | * text mode (activated by bpp = 0) | ||
32 | * interlaced mode variant (not available in text mode) | ||
33 | * doublescan mode variant (not available in text mode) | ||
34 | * panning in both directions | ||
35 | * suspend/resume support | ||
36 | * DPMS support | ||
37 | |||
38 | Text mode is supported even in higher resolutions, but there is limitation | ||
39 | to lower pixclocks (maximum between 50-60 MHz, depending on specific hardware). | ||
40 | This limitation is not enforced by driver. Text mode supports 8bit wide fonts | ||
41 | only (hardware limitation) and 16bit tall fonts (driver limitation). | ||
42 | |||
43 | There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with | ||
44 | packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode | ||
45 | with interleaved planes (1 byte interleave), MSB first. Both modes support | ||
46 | 8bit wide fonts only (driver limitation). | ||
47 | |||
48 | Suspend/resume works on systems that initialize video card during resume and | ||
49 | if device is active (for example used by fbcon). | ||
50 | |||
51 | |||
52 | Missing Features | ||
53 | ================ | ||
54 | (alias TODO list) | ||
55 | |||
56 | * secondary (not initialized by BIOS) device support | ||
57 | * big endian support | ||
58 | * Zorro bus support | ||
59 | * MMIO support | ||
60 | * 24 bpp mode support on more cards | ||
61 | * support for fontwidths != 8 in 4 bpp modes | ||
62 | * support for fontheight != 16 in text mode | ||
63 | * composite and external sync (is anyone able to test this?) | ||
64 | * hardware cursor | ||
65 | * video overlay support | ||
66 | * vsync synchronization | ||
67 | * feature connector support | ||
68 | * acceleration support (8514-like 2D, Virge 3D, busmaster transfers) | ||
69 | * better values for some magic registers (performance issues) | ||
70 | |||
71 | |||
72 | Known bugs | ||
73 | ========== | ||
74 | |||
75 | * cursor disable in text mode doesn't work | ||
76 | |||
77 | -- | ||
78 | Ondrej Zajicek <santiago@crfreenet.org> | ||