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68 lines
2.0 KiB
68 lines
2.0 KiB
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arkfb - fbdev driver for ARK Logic chips |
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Supported Hardware |
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ARK 2000PV chip |
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ICS 5342 ramdac |
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- only BIOS initialized VGA devices supported |
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- probably not working on big endian |
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Supported Features |
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================== |
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* 4 bpp pseudocolor modes (with 18bit palette, two variants) |
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* 8 bpp pseudocolor mode (with 18bit palette) |
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* 16 bpp truecolor modes (RGB 555 and RGB 565) |
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* 24 bpp truecolor mode (RGB 888) |
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* 32 bpp truecolor mode (RGB 888) |
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* text mode (activated by bpp = 0) |
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* doublescan mode variant (not available in text mode) |
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* panning in both directions |
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* suspend/resume support |
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Text mode is supported even in higher resolutions, but there is limitation to |
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lower pixclocks (i got maximum about 70 MHz, it is dependent on specific |
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hardware). This limitation is not enforced by driver. Text mode supports 8bit |
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wide fonts only (hardware limitation) and 16bit tall fonts (driver |
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limitation). Unfortunately character attributes (like color) in text mode are |
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broken for unknown reason, so its usefulness is limited. |
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There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with |
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packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode |
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with interleaved planes (1 byte interleave), MSB first. Both modes support |
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8bit wide fonts only (driver limitation). |
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Suspend/resume works on systems that initialize video card during resume and |
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if device is active (for example used by fbcon). |
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Missing Features |
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================ |
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(alias TODO list) |
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* secondary (not initialized by BIOS) device support |
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* big endian support |
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* DPMS support |
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* MMIO support |
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* interlaced mode variant |
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* support for fontwidths != 8 in 4 bpp modes |
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* support for fontheight != 16 in text mode |
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* hardware cursor |
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* vsync synchronization |
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* feature connector support |
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* acceleration support (8514-like 2D) |
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Known bugs |
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========== |
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* character attributes (and cursor) in text mode are broken |
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-- |
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Ondrej Zajicek <[email protected]>
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