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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> | ||
