arch/c6x/include/asm/system.h

   1 /*
   2  *  Port on Texas Instruments TMS320C6x architecture
   3  *
   4  *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
   5  *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  */
  11 #ifndef _ASM_C6X_SYSTEM_H
  12 #define _ASM_C6X_SYSTEM_H
  13
  14 #include <linux/linkage.h>
  15 #include <linux/irqflags.h>
  16
  17 #define prepare_to_switch()    do { } while (0)
  18
  19 struct task_struct;
  20 struct thread_struct;
  21 asmlinkage void *__switch_to(struct thread_struct *prev,
  22                              struct thread_struct *next,
  23                              struct task_struct *tsk);
  24
  25 #define switch_to(prev, next, last)                             \
  26         do {                                                    \
  27                 current->thread.wchan = (u_long) __builtin_return_address(0); \
  28                 (last) = __switch_to(&(prev)->thread,           \
  29                                      &(next)->thread, (prev));  \
  30                 mb();                                           \
  31                 current->thread.wchan = 0;                      \
  32         } while (0)
  33
  34 /* Reset the board */
  35 #define HARD_RESET_NOW()
  36
  37 #define get_creg(reg) \
  38         ({ unsigned int __x; \
  39            asm volatile ("mvc .s2 " #reg ",%0\n" : "=b"(__x)); __x; })
  40
  41 #define set_creg(reg, v) \
  42         do { unsigned int __x = (unsigned int)(v); \
  43                 asm volatile ("mvc .s2 %0," #reg "\n" : : "b"(__x)); \
  44         } while (0)
  45
  46 #define or_creg(reg, n) \
  47         do { unsigned __x, __n = (unsigned)(n);           \
  48                 asm volatile ("mvc .s2 " #reg ",%0\n"     \
  49                               "or  .l2 %1,%0,%0\n"        \
  50                               "mvc .s2 %0," #reg "\n"     \
  51                               "nop\n"                     \
  52                               : "=&b"(__x) : "b"(__n));   \
  53         } while (0)
  54
  55 #define and_creg(reg, n) \
  56         do { unsigned __x, __n = (unsigned)(n);           \
  57                 asm volatile ("mvc .s2 " #reg ",%0\n"     \
  58                               "and .l2 %1,%0,%0\n"        \
  59                               "mvc .s2 %0," #reg "\n"     \
  60                               "nop\n"    \
  61                               : "=&b"(__x) : "b"(__n));   \
  62         } while (0)
  63
  64 #define get_coreid() (get_creg(DNUM) & 0xff)
  65
  66 /* Set/get IST */
  67 #define set_ist(x)      set_creg(ISTP, x)
  68 #define get_ist()       get_creg(ISTP)
  69
  70 /*
  71  * Exception management
  72  */
  73 asmlinkage void enable_exception(void);
  74 #define disable_exception()
  75 #define get_except_type()        get_creg(EFR)
  76 #define ack_exception(type)      set_creg(ECR, 1 << (type))
  77 #define get_iexcept()            get_creg(IERR)
  78 #define set_iexcept(mask)        set_creg(IERR, (mask))
  79
  80 /*
  81  * Misc. functions
  82  */
  83 #define nop()                    asm("NOP\n");
  84 #define mb()                     barrier()
  85 #define rmb()                    barrier()
  86 #define wmb()                    barrier()
  87 #define set_mb(var, value)       do { var = value;  mb(); } while (0)
  88 #define set_wmb(var, value)      do { var = value; wmb(); } while (0)
  89
  90 #define smp_mb()                 barrier()
  91 #define smp_rmb()                barrier()
  92 #define smp_wmb()                barrier()
  93 #define smp_read_barrier_depends()      do { } while (0)
  94
  95 #define xchg(ptr, x) \
  96         ((__typeof__(*(ptr)))__xchg((unsigned int)(x), (void *) (ptr), \
  97                                     sizeof(*(ptr))))
  98 #define tas(ptr)    xchg((ptr), 1)
  99
 100 unsigned int _lmbd(unsigned int, unsigned int);
 101 unsigned int _bitr(unsigned int);
 102
 103 struct __xchg_dummy { unsigned int a[100]; };
 104 #define __xg(x) ((volatile struct __xchg_dummy *)(x))
 105
 106 static inline unsigned int __xchg(unsigned int x, volatile void *ptr, int size)
 107 {
 108         unsigned int tmp;
 109         unsigned long flags;
 110
 111         local_irq_save(flags);
 112
 113         switch (size) {
 114         case 1:
 115                 tmp = 0;
 116                 tmp = *((unsigned char *) ptr);
 117                 *((unsigned char *) ptr) = (unsigned char) x;
 118                 break;
 119         case 2:
 120                 tmp = 0;
 121                 tmp = *((unsigned short *) ptr);
 122                 *((unsigned short *) ptr) = x;
 123                 break;
 124         case 4:
 125                 tmp = 0;
 126                 tmp = *((unsigned int *) ptr);
 127                 *((unsigned int *) ptr) = x;
 128                 break;
 129         }
 130         local_irq_restore(flags);
 131         return tmp;
 132 }
 133
 134 #include <asm-generic/cmpxchg-local.h>
 135
 136 /*
 137  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 138  * them available.
 139  */
 140 #define cmpxchg_local(ptr, o, n)                                        \
 141         ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr),             \
 142                                                      (unsigned long)(o), \
 143                                                      (unsigned long)(n), \
 144                                                      sizeof(*(ptr))))
 145 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 146
 147 #include <asm-generic/cmpxchg.h>
 148
 149 #define _extu(x, s, e)                                                  \
 150         ({      unsigned int __x;                                       \
 151                 asm volatile ("extu .S2 %3,%1,%2,%0\n" :                \
 152                               "=b"(__x) : "n"(s), "n"(e), "b"(x));      \
 153                __x; })
 154
 155
 156 extern unsigned int c6x_core_freq;
 157
 158 struct pt_regs;
 159
 160 extern void die(char *str, struct pt_regs *fp, int nr);
 161 extern asmlinkage int process_exception(struct pt_regs *regs);
 162 extern void time_init(void);
 163 extern void free_initmem(void);
 164
 165 extern void (*c6x_restart)(void);
 166 extern void (*c6x_halt)(void);
 167
 168 #endif /* _ASM_C6X_SYSTEM_H */