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//

//

//    Copyright 2010 TheSeven

//

//

//    This file is part of emCORE.

//

//    emCORE is free software: you can redistribute it and/or

//    modify it under the terms of the GNU General Public License as

//    published by the Free Software Foundation, either version 2 of the

//    License, or (at your option) any later version.

//

//    emCORE is distributed in the hope that it will be useful,

//    but WITHOUT ANY WARRANTY; without even the implied warranty of

//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

//    See the GNU General Public License for more details.

//

//    You should have received a copy of the GNU General Public License along

//    with emCORE.  If not, see <http://www.gnu.org/licenses/>.

//

//

#ifndef __UTIL_H__

#define __UTIL_H__

#include "global.h"

#ifndef NULL

#define NULL ((void*)0)

#endif

#ifndef MIN

#define MIN(a, b) (((a)<(b))?(a):(b))

#endif

#ifndef MAX

#define MAX(a, b) (((a)>(b))?(a):(b))

#endif

/* return number of elements in array a */

#define ARRAYLEN(a) (sizeof(a)/sizeof((a)[0]))

/* return p incremented by specified number of bytes */

#define SKIPBYTES(p, count) ((typeof (p))((char *)(p) + (count)))

#define BIT(x) (1 << (x))

#define BITRANGE(x, y) ((0xfffffffful >> (31 + (x) - (y))) << (x))

#define ERR_RC(val) (BIT(31) | (val))

#define IS_ERR(val) (val & BIT(31))

#define RET_ERR(val)                                           \

{                                                              \

    return ERR_RC(val);                                        \

}

#define RET_ERR_MTX(val, mutex)                                \

{                                                              \

    mutex_unlock(mutex);                                       \

    return ERR_RC(val);                                        \

}

#define PASS_RC(expr, bits, val)                               \

{                                                              \

    int PASS_RC_rc = (expr);                                   \

    if (IS_ERR(PASS_RC_rc))                                    \

        return ERR_RC((PASS_RC_rc << (bits)) | (val));         \

}

#define PASS_RC_MTX(expr, bits, val, mutex)                    \

{                                                              \

    int PASS_RC_MTX_rc = (expr);                               \

    if (IS_ERR(PASS_RC_MTX_rc))                                \

    {                                                          \

        mutex_unlock(mutex);                                   \

        return ERR_RC((PASS_RC_MTX_rc << (bits)) | (val));     \

    }                                                          \

}

#define P2_M1(p2)  ((1 << (p2))-1)

/* align up or down to nearest 2^p2 */

#define ALIGN_DOWN_P2(n, p2) ((n) & ~P2_M1(p2))

#define ALIGN_UP_P2(n, p2)   ALIGN_DOWN_P2((n) + P2_M1(p2),p2)

/* align up or down to nearest integer multiple of a */

#define ALIGN_DOWN(n, a)     ((n)/(a)*(a))

#define ALIGN_UP(n, a)       ALIGN_DOWN((n)+((a)-1),a)

/* align start and end of buffer to nearest integer multiple of a */

#define ALIGN_BUFFER(ptr,len,align) \

{\

    uintptr_t tmp_ptr1 = (uintptr_t)ptr; \

    uintptr_t tmp_ptr2 = tmp_ptr1 + len;\

    tmp_ptr1 = ALIGN_UP(tmp_ptr1,align); \

    tmp_ptr2 = ALIGN_DOWN(tmp_ptr2,align); \

    len = tmp_ptr2 - tmp_ptr1; \

    ptr = (typeof(ptr))tmp_ptr1; \

}

/* live endianness conversion */

#ifdef LITTLE_ENDIAN

#define letoh16(x) (x)

#define letoh32(x) (x)

#define htole16(x) (x)

#define htole32(x) (x)

#define betoh16(x) swap16(x)

#define betoh32(x) swap32(x)

#define htobe16(x) swap16(x)

#define htobe32(x) swap32(x)

#define swap_odd_even_be32(x) (x)

#define swap_odd_even_le32(x) swap_odd_even32(x)

#else

#define letoh16(x) swap16(x)

#define letoh32(x) swap32(x)

#define htole16(x) swap16(x)

#define htole32(x) swap32(x)

#define betoh16(x) (x)

#define betoh32(x) (x)

#define htobe16(x) (x)

#define htobe32(x) (x)

#define swap_odd_even_be32(x) swap_odd_even32(x)

#define swap_odd_even_le32(x) (x)

#endif

/* static endianness conversion */

#define SWAP_16(x) ((typeof(x))(unsigned short)(((unsigned short)(x) >> 8) | \

                                                ((unsigned short)(x) << 8)))

#define SWAP_32(x) ((typeof(x))(unsigned long)( ((unsigned long)(x) >> 24) | \

                                               (((unsigned long)(x) & 0xff0000ul) >> 8) | \

                                               (((unsigned long)(x) & 0xff00ul) << 8) | \

                                                ((unsigned long)(x) << 24)))

#ifdef RLITTLE_ENDIAN

#define LE_TO_H16(x) (x)

#define LE_TO_H32(x) (x)

#define H_TO_LE16(x) (x)

#define H_TO_LE32(x) (x)

#define BE_TO_H16(x) SWAP_16(x)

#define BE_TO_H32(x) SWAP_32(x)

#define H_TO_BE16(x) SWAP_16(x)

#define H_TO_BE32(x) SWAP_32(x)

#else

#define LE_TO_H16(x) SWAP_16(x)

#define LE_TO_H32(x) SWAP_32(x)

#define H_TO_LE16(x) SWAP_16(x)

#define H_TO_LE32(x) SWAP_32(x)

#define BE_TO_H16(x) (x)

#define BE_TO_H32(x) (x)

#define H_TO_BE16(x) (x)

#define H_TO_BE32(x) (x)

#endif

/* Get the byte offset of a type's member */

#define OFFSETOF(type, membername) ((off_t)&((type *)0)->membername)

/* Get the type pointer from one of its members */

#define TYPE_FROM_MEMBER(type, memberptr, membername) \

    ((type *)((intptr_t)(memberptr) - OFFSETOF(type, membername)))

static inline uint16_t swap16(uint16_t value)

    /*

      result[15..8] = value[ 7..0];

      result[ 7..0] = value[15..8];

    */

{

    return (value >> 8) | (value << 8);

}

static inline uint32_t swap32(uint32_t value)

    /*

      result[31..24] = value[ 7.. 0];

      result[23..16] = value[15.. 8];

      result[15.. 8] = value[23..16];

      result[ 7.. 0] = value[31..24];

    */

{

    uint32_t hi = swap16(value >> 16);

    uint32_t lo = swap16(value & 0xffff);

    return (lo << 16) | hi;

}

static inline uint32_t swap_odd_even32(uint32_t value)

{

    /*

      result[31..24],[15.. 8] = value[23..16],[ 7.. 0]

      result[23..16],[ 7.. 0] = value[31..24],[15.. 8]

    */

    uint32_t t = value & 0xff00ff00;

    return (t >> 8) | ((t ^ value) << 8);

}

#ifndef BIT_N

#define BIT_N(n) (1U << (n))

#endif

#ifndef CACHEALIGN_SIZE /* could be elsewhere for a particular reason */

#ifdef CACHEALIGN_BITS

/* 2^CACHEALIGN_BITS = the byte size */

#define CACHEALIGN_SIZE (1u << CACHEALIGN_BITS)

#else

#define CACHEALIGN_SIZE 16  /* FIXME */

#endif

#endif /* CACHEALIGN_SIZE */

#define CACHEALIGN_ATTR __attribute__((aligned(CACHEALIGN_SIZE)))

/* Aligns x up to a CACHEALIGN_SIZE boundary */

#define CACHEALIGN_UP(x) \

    ((typeof (x))ALIGN_UP_P2((uintptr_t)(x), CACHEALIGN_BITS))

/* Aligns x down to a CACHEALIGN_SIZE boundary */

#define CACHEALIGN_DOWN(x) \

    ((typeof (x))ALIGN_DOWN_P2((uintptr_t)(x), CACHEALIGN_BITS))

/* Aligns at least to the greater of size x or CACHEALIGN_SIZE */

#define CACHEALIGN_AT_LEAST_ATTR(x) \

    __attribute__((aligned(CACHEALIGN_UP(x))))

/* Aligns a buffer pointer and size to proper boundaries */

#define CACHEALIGN_BUFFER(start, size) \

    ALIGN_BUFFER((start), (size), CACHEALIGN_SIZE)

/* Double-cast to avoid 'dereferencing type-punned pointer will

 * break strict aliasing rules' B.S. */

#define PUN_PTR(type, p) ((type)(intptr_t)(p))

#endif