kernel/arch/xtensa/include/asm/traps.h

   1 /*
   2  * arch/xtensa/include/asm/traps.h
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 2012 Tensilica Inc.
   9  */
  10 #ifndef _XTENSA_TRAPS_H
  11 #define _XTENSA_TRAPS_H
  12
  13 #include <asm/ptrace.h>
  14
  15 /*
  16  * handler must be either of the following:
  17  *  void (*)(struct pt_regs *regs);
  18  *  void (*)(struct pt_regs *regs, unsigned long exccause);
  19  */
  20 extern void * __init trap_set_handler(int cause, void *handler);
  21 extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
  22 void secondary_trap_init(void);
  23
  24 static inline void spill_registers(void)
  25 {
  26 #if XCHAL_NUM_AREGS > 16
  27         __asm__ __volatile__ (
  28                 "       call8   1f\n"
  29                 "       _j      2f\n"
  30                 "       retw\n"
  31                 "       .align  4\n"
  32                 "1:\n"
  33 #if XCHAL_NUM_AREGS == 32
  34                 "       _entry  a1, 32\n"
  35                 "       addi    a8, a0, 3\n"
  36                 "       _entry  a1, 16\n"
  37                 "       mov     a12, a12\n"
  38                 "       retw\n"
  39 #else
  40                 "       _entry  a1, 48\n"
  41                 "       call12  1f\n"
  42                 "       retw\n"
  43                 "       .align  4\n"
  44                 "1:\n"
  45                 "       .rept   (" __stringify(XCHAL_NUM_AREGS) " - 16) / 12\n"
  46                 "       _entry  a1, 48\n"
  47                 "       mov     a12, a0\n"
  48                 "       .endr\n"
  49                 "       _entry  a1, 16\n"
  50 #if XCHAL_NUM_AREGS % 12 == 0
  51                 "       mov     a12, a12\n"
  52 #elif XCHAL_NUM_AREGS % 12 == 4
  53                 "       mov     a4, a4\n"
  54 #elif XCHAL_NUM_AREGS % 12 == 8
  55                 "       mov     a8, a8\n"
  56 #endif
  57                 "       retw\n"
  58 #endif
  59                 "2:\n"
  60                 : : : "a8", "a9", "memory");
  61 #else
  62         __asm__ __volatile__ (
  63                 "       mov     a12, a12\n"
  64                 : : : "memory");
  65 #endif
  66 }
  67
  68 #endif /* _XTENSA_TRAPS_H */