arch/xtensa/include/asm/ptrace.h

   1 /*
   2  * include/asm-xtensa/ptrace.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) 2001 - 2005 Tensilica Inc.
   9  */
  10 #ifndef _XTENSA_PTRACE_H
  11 #define _XTENSA_PTRACE_H
  12
  13 #include <uapi/asm/ptrace.h>
  14
  15 /*
  16  * Kernel stack
  17  *
  18  *              +-----------------------+  -------- STACK_SIZE
  19  *              |     register file     |  |
  20  *              +-----------------------+  |
  21  *              |    struct pt_regs     |  |
  22  *              +-----------------------+  | ------ PT_REGS_OFFSET
  23  * double       :  16 bytes spill area  :  |  ^
  24  * excetion     :- - - - - - - - - - - -:  |  |
  25  * frame        :    struct pt_regs     :  |  |
  26  *              :- - - - - - - - - - - -:  |  |
  27  *              |                       |  |  |
  28  *              |     memory stack      |  |  |
  29  *              |                       |  |  |
  30  *              ~                       ~  ~  ~
  31  *              ~                       ~  ~  ~
  32  *              |                       |  |  |
  33  *              |                       |  |  |
  34  *              +-----------------------+  |  | --- STACK_BIAS
  35  *              |  struct task_struct   |  |  |  ^
  36  *  current --> +-----------------------+  |  |  |
  37  *              |  struct thread_info   |  |  |  |
  38  *              +-----------------------+ --------
  39  */
  40
  41 #define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
  42
  43 /*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
  44
  45 #define EXC_TABLE_KSTK          0x004   /* Kernel Stack */
  46 #define EXC_TABLE_DOUBLE_SAVE   0x008   /* Double exception save area for a0 */
  47 #define EXC_TABLE_FIXUP         0x00c   /* Fixup handler */
  48 #define EXC_TABLE_PARAM         0x010   /* For passing a parameter to fixup */
  49 #define EXC_TABLE_SYSCALL_SAVE  0x014   /* For fast syscall handler */
  50 #define EXC_TABLE_FAST_USER     0x100   /* Fast user exception handler */
  51 #define EXC_TABLE_FAST_KERNEL   0x200   /* Fast kernel exception handler */
  52 #define EXC_TABLE_DEFAULT       0x300   /* Default C-Handler */
  53 #define EXC_TABLE_SIZE          0x400
  54
  55 #ifndef __ASSEMBLY__
  56
  57 #include <asm/coprocessor.h>
  58
  59 /*
  60  * This struct defines the way the registers are stored on the
  61  * kernel stack during a system call or other kernel entry.
  62  */
  63 struct pt_regs {
  64         unsigned long pc;               /*   4 */
  65         unsigned long ps;               /*   8 */
  66         unsigned long depc;             /*  12 */
  67         unsigned long exccause;         /*  16 */
  68         unsigned long excvaddr;         /*  20 */
  69         unsigned long debugcause;       /*  24 */
  70         unsigned long wmask;            /*  28 */
  71         unsigned long lbeg;             /*  32 */
  72         unsigned long lend;             /*  36 */
  73         unsigned long lcount;           /*  40 */
  74         unsigned long sar;              /*  44 */
  75         unsigned long windowbase;       /*  48 */
  76         unsigned long windowstart;      /*  52 */
  77         unsigned long syscall;          /*  56 */
  78         unsigned long icountlevel;      /*  60 */
  79         unsigned long scompare1;        /*  64 */
  80         unsigned long threadptr;        /*  68 */
  81
  82         /* Additional configurable registers that are used by the compiler. */
  83         xtregs_opt_t xtregs_opt;
  84
  85         /* Make sure the areg field is 16 bytes aligned. */
  86         int align[0] __attribute__ ((aligned(16)));
  87
  88         /* current register frame.
  89          * Note: The ESF for kernel exceptions ends after 16 registers!
  90          */
  91         unsigned long areg[16];
  92 };
  93
  94 #include <variant/core.h>
  95
  96 # define arch_has_single_step() (1)
  97 # define task_pt_regs(tsk) ((struct pt_regs*) \
  98         (task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
  99 # define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
 100 # define instruction_pointer(regs) ((regs)->pc)
 101 # define return_pointer(regs) (MAKE_PC_FROM_RA((regs)->areg[0], \
 102                                                (regs)->areg[1]))
 103
 104 # ifndef CONFIG_SMP
 105 #  define profile_pc(regs) instruction_pointer(regs)
 106 # else
 107 #  define profile_pc(regs)                                              \
 108         ({                                                              \
 109                 in_lock_functions(instruction_pointer(regs)) ?          \
 110                 return_pointer(regs) : instruction_pointer(regs);       \
 111         })
 112 # endif
 113
 114 #define user_stack_pointer(regs) ((regs)->areg[1])
 115
 116 #else   /* __ASSEMBLY__ */
 117
 118 # include <asm/asm-offsets.h>
 119 #define PT_REGS_OFFSET    (KERNEL_STACK_SIZE - PT_USER_SIZE)
 120
 121 #endif  /* !__ASSEMBLY__ */
 122
 123 #endif  /* _XTENSA_PTRACE_H */