unaligned.h

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/*
 *  Port on Texas Instruments TMS320C6x architecture
 *
 *  Copyright (C) 2004, 2009, 2010 Texas Instruments Incorporated
 *  Author: Aurelien Jacquiot ([email protected])
 *  Rewritten for 2.6.3x: Mark Salter <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */
#ifndef _ASM_C6X_UNALIGNED_H
#define _ASM_C6X_UNALIGNED_H

#include <linux/swab.h>

/*
 * The C64x+ can do unaligned word and dword accesses in hardware
 * using special load/store instructions.
 */

static inline u16 get_unaligned_le16(const void *p)
{
    const u8 *_p = p;
    return _p[0] | _p[1] << 8;
}

static inline u16 get_unaligned_be16(const void *p)
{
    const u8 *_p = p;
    return _p[0] << 8 | _p[1];
}

static inline void put_unaligned_le16(u16 val, void *p)
{
    u8 *_p = p;
    _p[0] = val;
    _p[1] = val >> 8;
}

static inline void put_unaligned_be16(u16 val, void *p)
{
    u8 *_p = p;
    _p[0] = val >> 8;
    _p[1] = val;
}

static inline u32 get_unaligned32(const void *p)
{
    u32 val = (u32) p;
    asm (" ldnw .d1t1   *%0,%0\n"
         " nop     4\n"
         : "+a"(val));
    return val;
}

static inline void put_unaligned32(u32 val, void *p)
{
    asm volatile (" stnw    .d2t1   %0,*%1\n"
              : : "a"(val), "b"(p) : "memory");
}

static inline u64 get_unaligned64(const void *p)
{
    u64 val;
    asm volatile (" ldndw   .d1t1   *%1,%0\n"
              " nop     4\n"
              : "=a"(val) : "a"(p));
    return val;
}

static inline void put_unaligned64(u64 val, const void *p)
{
    asm volatile (" stndw   .d2t1   %0,*%1\n"
              : : "a"(val), "b"(p) : "memory");
}

#ifdef CONFIG_CPU_BIG_ENDIAN

#define get_unaligned_le32(p)    __swab32(get_unaligned32(p))
#define get_unaligned_le64(p)    __swab64(get_unaligned64(p))
#define get_unaligned_be32(p)    get_unaligned32(p)
#define get_unaligned_be64(p)    get_unaligned64(p)
#define put_unaligned_le32(v, p) put_unaligned32(__swab32(v), (p))
#define put_unaligned_le64(v, p) put_unaligned64(__swab64(v), (p))
#define put_unaligned_be32(v, p) put_unaligned32((v), (p))
#define put_unaligned_be64(v, p) put_unaligned64((v), (p))
#define get_unaligned   __get_unaligned_be
#define put_unaligned   __put_unaligned_be

#else

#define get_unaligned_le32(p)    get_unaligned32(p)
#define get_unaligned_le64(p)    get_unaligned64(p)
#define get_unaligned_be32(p)    __swab32(get_unaligned32(p))
#define get_unaligned_be64(p)    __swab64(get_unaligned64(p))
#define put_unaligned_le32(v, p) put_unaligned32((v), (p))
#define put_unaligned_le64(v, p) put_unaligned64((v), (p))
#define put_unaligned_be32(v, p) put_unaligned32(__swab32(v), (p))
#define put_unaligned_be64(v, p) put_unaligned64(__swab64(v), (p))
#define get_unaligned   __get_unaligned_le
#define put_unaligned   __put_unaligned_le

#endif

/*
 * Cause a link-time error if we try an unaligned access other than
 * 1,2,4 or 8 bytes long
 */
extern int __bad_unaligned_access_size(void);

#define __get_unaligned_le(ptr) (typeof(*(ptr)))({          \
    sizeof(*(ptr)) == 1 ? *(ptr) :                  \
      (sizeof(*(ptr)) == 2 ? get_unaligned_le16((ptr)) :        \
         (sizeof(*(ptr)) == 4 ? get_unaligned_le32((ptr)) :     \
        (sizeof(*(ptr)) == 8 ? get_unaligned_le64((ptr)) :  \
           __bad_unaligned_access_size())));            \
    })

#define __get_unaligned_be(ptr) (__force typeof(*(ptr)))({  \
    sizeof(*(ptr)) == 1 ? *(ptr) :                  \
      (sizeof(*(ptr)) == 2 ? get_unaligned_be16((ptr)) :        \
         (sizeof(*(ptr)) == 4 ? get_unaligned_be32((ptr)) :     \
        (sizeof(*(ptr)) == 8 ? get_unaligned_be64((ptr)) :  \
           __bad_unaligned_access_size())));            \
    })

#define __put_unaligned_le(val, ptr) ({                 \
    void *__gu_p = (ptr);                       \
    switch (sizeof(*(ptr))) {                   \
    case 1:                             \
        *(u8 *)__gu_p = (__force u8)(val);          \
        break;                          \
    case 2:                             \
        put_unaligned_le16((__force u16)(val), __gu_p);     \
        break;                          \
    case 4:                             \
        put_unaligned_le32((__force u32)(val), __gu_p);     \
        break;                          \
    case 8:                             \
        put_unaligned_le64((__force u64)(val), __gu_p);     \
        break;                          \
    default:                            \
        __bad_unaligned_access_size();              \
        break;                          \
    }                               \
    (void)0; })

#define __put_unaligned_be(val, ptr) ({                 \
    void *__gu_p = (ptr);                       \
    switch (sizeof(*(ptr))) {                   \
    case 1:                             \
        *(u8 *)__gu_p = (__force u8)(val);          \
        break;                          \
    case 2:                             \
        put_unaligned_be16((__force u16)(val), __gu_p);     \
        break;                          \
    case 4:                             \
        put_unaligned_be32((__force u32)(val), __gu_p);     \
        break;                          \
    case 8:                             \
        put_unaligned_be64((__force u64)(val), __gu_p);     \
        break;                          \
    default:                            \
        __bad_unaligned_access_size();              \
        break;                          \
    }                               \
    (void)0; })

#endif /* _ASM_C6X_UNALIGNED_H */