0001 ========================================
0002 arkfb - fbdev driver for ARK Logic chips
0003 ========================================
0004
0005
0006 Supported Hardware
0007 ==================
0008
0009 ARK 2000PV chip
0010 ICS 5342 ramdac
0011
0012 - only BIOS initialized VGA devices supported
0013 - probably not working on big endian
0014
0015
0016 Supported Features
0017 ==================
0018
0019 * 4 bpp pseudocolor modes (with 18bit palette, two variants)
0020 * 8 bpp pseudocolor mode (with 18bit palette)
0021 * 16 bpp truecolor modes (RGB 555 and RGB 565)
0022 * 24 bpp truecolor mode (RGB 888)
0023 * 32 bpp truecolor mode (RGB 888)
0024 * text mode (activated by bpp = 0)
0025 * doublescan mode variant (not available in text mode)
0026 * panning in both directions
0027 * suspend/resume support
0028
0029 Text mode is supported even in higher resolutions, but there is limitation to
0030 lower pixclocks (i got maximum about 70 MHz, it is dependent on specific
0031 hardware). This limitation is not enforced by driver. Text mode supports 8bit
0032 wide fonts only (hardware limitation) and 16bit tall fonts (driver
0033 limitation). Unfortunately character attributes (like color) in text mode are
0034 broken for unknown reason, so its usefulness is limited.
0035
0036 There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
0037 packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
0038 with interleaved planes (1 byte interleave), MSB first. Both modes support
0039 8bit wide fonts only (driver limitation).
0040
0041 Suspend/resume works on systems that initialize video card during resume and
0042 if device is active (for example used by fbcon).
0043
0044
0045 Missing Features
0046 ================
0047 (alias TODO list)
0048
0049 * secondary (not initialized by BIOS) device support
0050 * big endian support
0051 * DPMS support
0052 * MMIO support
0053 * interlaced mode variant
0054 * support for fontwidths != 8 in 4 bpp modes
0055 * support for fontheight != 16 in text mode
0056 * hardware cursor
0057 * vsync synchronization
0058 * feature connector support
0059 * acceleration support (8514-like 2D)
0060
0061
0062 Known bugs
0063 ==========
0064
0065 * character attributes (and cursor) in text mode are broken
0066
0067 --
0068 Ondrej Zajicek <santiago@crfreenet.org>
