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Diffstat (limited to 'drivers/video/fbdev/c2p_core.h')
| -rw-r--r-- | drivers/video/fbdev/c2p_core.h | 153 | 
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/video/fbdev/c2p_core.h b/drivers/video/fbdev/c2p_core.h new file mode 100644 index 00000000000..e1035a865fb --- /dev/null +++ b/drivers/video/fbdev/c2p_core.h @@ -0,0 +1,153 @@ +/* + *  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(); +} + + +    /* +     *  Transpose operations on 4 32-bit words +     */ + +static inline void transp4(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); +		return; + +	case 2: +		/* Single n x 2 block */ +		_transp(d, 0, 2, n, mask); +		_transp(d, 1, 3, n, mask); +		return; +	} + +	c2p_unsupported(); +} + + +    /* +     *  Transpose operations on 4 32-bit words (reverse order) +     */ + +static inline void transp4x(u32 d[], unsigned int n, unsigned int m) +{ +	u32 mask = get_mask(n); + +	switch (m) { +	case 2: +		/* Single n x 2 block */ +		_transp(d, 2, 0, n, mask); +		_transp(d, 3, 1, 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; +}  | 
