LXR uboot/include/asm-blackfin/system.h

   1/*
   2 * U-boot - system.h
   3 *
   4 * Copyright (c) 2005-2007 Analog Devices Inc.
   5 *
   6 * See file CREDITS for list of people who contributed to this
   7 * project.
   8 *
   9 * This program is free software; you can redistribute it and/or
  10 * modify it under the terms of the GNU General Public License as
  11 * published by the Free Software Foundation; either version 2 of
  12 * the License, or (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 *
  19 * You should have received a copy of the GNU General Public License
  20 * along with this program; if not, write to the Free Software
  21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  22 * MA 02110-1301 USA
  23 */
  24
  25#ifndef _BLACKFIN_SYSTEM_H
  26#define _BLACKFIN_SYSTEM_H
  27
  28/*
  29 * Interrupt configuring macros.
  30 */
  31
  32extern int irq_flags;
  33
  34#define local_irq_enable() \
  35        __asm__ __volatile__ ( \
  36                "sti %0;" \
  37                : \
  38                : "d" (irq_flags) \
  39        )
  40
  41#define local_irq_disable() \
  42        do { \
  43                int __tmp_dummy; \
  44                __asm__ __volatile__ ( \
  45                        "cli %0;" \
  46                        : "=d" (__tmp_dummy) \
  47                ); \
  48        } while (0)
  49
  50# define local_irq_save(x) \
  51        __asm__ __volatile__ ( \
  52                "cli %0;" \
  53                : "=&d" (x) \
  54        )
  55
  56#define local_save_flags(x) \
  57        __asm__ __volatile__ ( \
  58                "cli %0;" \
  59                "sti %0;" \
  60                : "=d" (x) \
  61        )
  62
  63#define irqs_enabled_from_flags(x) ((x) != 0x1f)
  64
  65#define local_irq_restore(x) \
  66        do { \
  67                if (irqs_enabled_from_flags(x)) \
  68                        local_irq_enable(); \
  69        } while (0)
  70
  71/*
  72 * Force strict CPU ordering.
  73 */
  74#define nop()                   asm volatile ("nop;\n\t"::)
  75#define mb()                    asm volatile (""   : : :"memory")
  76#define rmb()                   asm volatile (""   : : :"memory")
  77#define wmb()                   asm volatile (""   : : :"memory")
  78#define set_rmb(var, value)     do { xchg(&var, value); } while (0)
  79#define set_mb(var, value)      set_rmb(var, value)
  80#define set_wmb(var, value)     do { var = value; wmb(); } while (0)
  81
  82#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
  83
  84struct __xchg_dummy {
  85        unsigned long a[100];
  86};
  87#define __xg(x) ((volatile struct __xchg_dummy *)(x))
  88
  89static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
  90                                   int size)
  91{
  92        unsigned long tmp = 0;
  93        unsigned long flags = 0;
  94
  95        local_irq_save(flags);
  96
  97        switch (size) {
  98        case 1:
  99                __asm__ __volatile__
 100                        ("%0 = b%2 (z);\n\t"
 101                         "b%2 = %1;\n\t"
 102                         : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
 103                break;
 104        case 2:
 105                __asm__ __volatile__
 106                        ("%0 = w%2 (z);\n\t"
 107                         "w%2 = %1;\n\t"
 108                         : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
 109                break;
 110        case 4:
 111                __asm__ __volatile__
 112                        ("%0 = %2;\n\t"
 113                         "%2 = %1;\n\t"
 114                         : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
 115                break;
 116        }
 117        local_irq_restore(flags);
 118        return tmp;
 119}
 120
 121#endif  /* _BLACKFIN_SYSTEM_H */
 122