diff options
author | Geert Uytterhoeven <geert@linux-m68k.org> | 2009-01-04 11:58:20 +0100 |
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committer | Geert Uytterhoeven <geert@linux-m68k.org> | 2009-01-12 20:56:31 +0100 |
commit | 2cd1de0a0ff1d3da08ff1f1437cf4a44deae6a00 (patch) | |
tree | d384dea3a349ee2f2f897e242882cbbb7e56a705 /drivers/video/c2p_core.h | |
parent | 1f034456c140a8677d0ff3a9bdb3c4b620aae2cb (diff) |
fbdev: c2p - Extract common c2p core to c2p_core.h
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'drivers/video/c2p_core.h')
-rw-r--r-- | drivers/video/c2p_core.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/drivers/video/c2p_core.h b/drivers/video/c2p_core.h new file mode 100644 index 000000000000..3573cf723e43 --- /dev/null +++ b/drivers/video/c2p_core.h @@ -0,0 +1,106 @@ +/* + * Fast C2P (Chunky-to-Planar) Conversion + * + * Copyright (C) 2003-2008 Geert Uytterhoeven + * + * NOTES: + * - This code was inspired by Scout's C2P tutorial + * - It assumes to run on a big endian system + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + + + /* + * Basic transpose step + */ + +static inline void _transp(u32 d[], unsigned int i1, unsigned int i2, + unsigned int shift, u32 mask) +{ + u32 t = (d[i1] ^ (d[i2] >> shift)) & mask; + + d[i1] ^= t; + d[i2] ^= t << shift; +} + + +extern void c2p_unsupported(void); + +static inline u32 get_mask(unsigned int n) +{ + switch (n) { + case 1: + return 0x55555555; + + case 2: + return 0x33333333; + + case 4: + return 0x0f0f0f0f; + + case 8: + return 0x00ff00ff; + + case 16: + return 0x0000ffff; + } + + c2p_unsupported(); + return 0; +} + + + /* + * Transpose operations on 8 32-bit words + */ + +static inline void transp8(u32 d[], unsigned int n, unsigned int m) +{ + u32 mask = get_mask(n); + + switch (m) { + case 1: + /* First n x 1 block */ + _transp(d, 0, 1, n, mask); + /* Second n x 1 block */ + _transp(d, 2, 3, n, mask); + /* Third n x 1 block */ + _transp(d, 4, 5, n, mask); + /* Fourth n x 1 block */ + _transp(d, 6, 7, n, mask); + return; + + case 2: + /* First n x 2 block */ + _transp(d, 0, 2, n, mask); + _transp(d, 1, 3, n, mask); + /* Second n x 2 block */ + _transp(d, 4, 6, n, mask); + _transp(d, 5, 7, n, mask); + return; + + case 4: + /* Single n x 4 block */ + _transp(d, 0, 4, n, mask); + _transp(d, 1, 5, n, mask); + _transp(d, 2, 6, n, mask); + _transp(d, 3, 7, n, mask); + return; + } + + c2p_unsupported(); +} + + + /* + * Compose two values, using a bitmask as decision value + * This is equivalent to (a & mask) | (b & ~mask) + */ + +static inline u32 comp(u32 a, u32 b, u32 mask) +{ + return ((a ^ b) & mask) ^ b; +} |