[linux.git] / drivers / video / c2p_core.h

/*
 *  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;
}
Commit	Line	Data
2cd1de0a GU	1	/*
	2	* Fast C2P (Chunky-to-Planar) Conversion
	3	*
	4	* Copyright (C) 2003-2008 Geert Uytterhoeven
	5	*
	6	* NOTES:
	7	* - This code was inspired by Scout's C2P tutorial
	8	* - It assumes to run on a big endian system
	9	*
	10	* This file is subject to the terms and conditions of the GNU General Public
	11	* License. See the file COPYING in the main directory of this archive
	12	* for more details.
	13	*/
	14
	15
	16	/*
	17	* Basic transpose step
	18	*/
	19
	20	static inline void _transp(u32 d[], unsigned int i1, unsigned int i2,
	21	unsigned int shift, u32 mask)
	22	{
	23	u32 t = (d[i1] ^ (d[i2] >> shift)) & mask;
	24
	25	d[i1] ^= t;
	26	d[i2] ^= t << shift;
	27	}
	28
	29
	30	extern void c2p_unsupported(void);
	31
	32	static inline u32 get_mask(unsigned int n)
	33	{
	34	switch (n) {
	35	case 1:
	36	return 0x55555555;
	37
	38	case 2:
	39	return 0x33333333;
	40
	41	case 4:
	42	return 0x0f0f0f0f;
	43
	44	case 8:
	45	return 0x00ff00ff;
	46
	47	case 16:
	48	return 0x0000ffff;
	49	}
	50
	51	c2p_unsupported();
	52	return 0;
	53	}
	54
	55
	56	/*
	57	* Transpose operations on 8 32-bit words
	58	*/
	59
	60	static inline void transp8(u32 d[], unsigned int n, unsigned int m)
	61	{
	62	u32 mask = get_mask(n);
	63
	64	switch (m) {
65	case 1:
66	/* First n x 1 block */
67	_transp(d, 0, 1, n, mask);
68	/* Second n x 1 block */
69	_transp(d, 2, 3, n, mask);
70	/* Third n x 1 block */
71	_transp(d, 4, 5, n, mask);
72	/* Fourth n x 1 block */
73	_transp(d, 6, 7, n, mask);
74	return;
75
76	case 2:
77	/* First n x 2 block */
78	_transp(d, 0, 2, n, mask);
79	_transp(d, 1, 3, n, mask);
80	/* Second n x 2 block */
81	_transp(d, 4, 6, n, mask);
82	_transp(d, 5, 7, n, mask);
83	return;
84
85	case 4:
86	/* Single n x 4 block */
87	_transp(d, 0, 4, n, mask);
88	_transp(d, 1, 5, n, mask);
89	_transp(d, 2, 6, n, mask);
90	_transp(d, 3, 7, n, mask);
91	return;
92	}
93
94	c2p_unsupported();
95	}
96
97
96f47d61 GU	98	/*
	99	* Transpose operations on 4 32-bit words
	100	*/
	101
	102	static inline void transp4(u32 d[], unsigned int n, unsigned int m)
	103	{
	104	u32 mask = get_mask(n);
	105
	106	switch (m) {
	107	case 1:
	108	/* First n x 1 block */
	109	_transp(d, 0, 1, n, mask);
	110	/* Second n x 1 block */
	111	_transp(d, 2, 3, n, mask);
	112	return;
	113
	114	case 2:
	115	/* Single n x 2 block */
	116	_transp(d, 0, 2, n, mask);
	117	_transp(d, 1, 3, n, mask);
	118	return;
	119	}
	120
	121	c2p_unsupported();
	122	}
	123
	124
	125	/*
	126	* Transpose operations on 4 32-bit words (reverse order)
	127	*/
	128
	129	static inline void transp4x(u32 d[], unsigned int n, unsigned int m)
	130	{
	131	u32 mask = get_mask(n);
	132
	133	switch (m) {
	134	case 2:
	135	/* Single n x 2 block */
	136	_transp(d, 2, 0, n, mask);
	137	_transp(d, 3, 1, n, mask);
	138	return;
	139	}
	140
	141	c2p_unsupported();
	142	}
	143
	144
2cd1de0a GU	145	/*
	146	* Compose two values, using a bitmask as decision value
	147	* This is equivalent to (a & mask) \| (b & ~mask)
	148	*/
	149
	150	static inline u32 comp(u32 a, u32 b, u32 mask)
	151	{
	152	return ((a ^ b) & mask) ^ b;
	153	}