0001 ===============================================================
0002 vt8623fb - fbdev driver for graphics core in VIA VT8623 chipset
0003 ===============================================================
0004
0005
0006 Supported Hardware
0007 ==================
0008
0009 VIA VT8623 [CLE266] chipset and its graphics core
0010 (known as CastleRock or Unichrome)
0011
0012 I tested vt8623fb on VIA EPIA ML-6000
0013
0014
0015 Supported Features
0016 ==================
0017
0018 * 4 bpp pseudocolor modes (with 18bit palette, two variants)
0019 * 8 bpp pseudocolor mode (with 18bit palette)
0020 * 16 bpp truecolor mode (RGB 565)
0021 * 32 bpp truecolor mode (RGB 888)
0022 * text mode (activated by bpp = 0)
0023 * doublescan mode variant (not available in text mode)
0024 * panning in both directions
0025 * suspend/resume support
0026 * DPMS support
0027
0028 Text mode is supported even in higher resolutions, but there is limitation to
0029 lower pixclocks (maximum about 100 MHz). This limitation is not enforced by
0030 driver. Text mode supports 8bit wide fonts only (hardware limitation) and
0031 16bit tall fonts (driver limitation).
0032
0033 There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
0034 packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
0035 with interleaved planes (1 byte interleave), MSB first. Both modes support
0036 8bit wide fonts only (driver limitation).
0037
0038 Suspend/resume works on systems that initialize video card during resume and
0039 if device is active (for example used by fbcon).
0040
0041
0042 Missing Features
0043 ================
0044 (alias TODO list)
0045
0046 * secondary (not initialized by BIOS) device support
0047 * MMIO support
0048 * interlaced mode variant
0049 * support for fontwidths != 8 in 4 bpp modes
0050 * support for fontheight != 16 in text mode
0051 * hardware cursor
0052 * video overlay support
0053 * vsync synchronization
0054 * acceleration support (8514-like 2D, busmaster transfers)
0055
0056
0057 Known bugs
0058 ==========
0059
0060 * cursor disable in text mode doesn't work
0061
0062
0063 --
0064 Ondrej Zajicek <santiago@crfreenet.org>
