include/asm-xtensa/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
  11 #ifndef _XTENSA_PTRACE_H
  12 #define _XTENSA_PTRACE_H
  13
  14 #include <asm/variant/core.h>
  15
  16 /*
  17  * Kernel stack
  18  *
  19  *              +-----------------------+  -------- STACK_SIZE
  20  *              |     register file     |  |
  21  *              +-----------------------+  |
  22  *              |    struct pt_regs     |  |
  23  *              +-----------------------+  | ------ PT_REGS_OFFSET
  24  * double       :  16 bytes spill area  :  |  ^
  25  * excetion     :- - - - - - - - - - - -:  |  |
  26  * frame        :    struct pt_regs     :  |  |
  27  *              :- - - - - - - - - - - -:  |  |
  28  *              |                       |  |  |
  29  *              |     memory stack      |  |  |
  30  *              |                       |  |  |
  31  *              ~                       ~  ~  ~
  32  *              ~                       ~  ~  ~
  33  *              |                       |  |  |
  34  *              |                       |  |  |
  35  *              +-----------------------+  |  | --- STACK_BIAS
  36  *              |  struct task_struct   |  |  |  ^
  37  *  current --> +-----------------------+  |  |  |
  38  *              |  struct thread_info   |  |  |  |
  39  *              +-----------------------+ --------
  40  */
  41
  42 #define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
  43
  44 /*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
  45
  46 #define EXC_TABLE_KSTK          0x004   /* Kernel Stack */
  47 #define EXC_TABLE_DOUBLE_SAVE   0x008   /* Double exception save area for a0 */
  48 #define EXC_TABLE_FIXUP         0x00c   /* Fixup handler */
  49 #define EXC_TABLE_PARAM         0x010   /* For passing a parameter to fixup */
  50 #define EXC_TABLE_SYSCALL_SAVE  0x014   /* For fast syscall handler */
  51 #define EXC_TABLE_FAST_USER     0x100   /* Fast user exception handler */
  52 #define EXC_TABLE_FAST_KERNEL   0x200   /* Fast kernel exception handler */
  53 #define EXC_TABLE_DEFAULT       0x300   /* Default C-Handler */
  54 #define EXC_TABLE_SIZE          0x400
  55
  56 /* Registers used by strace */
  57
  58 #define REG_A_BASE      0xfc000000
  59 #define REG_AR_BASE     0x04000000
  60 #define REG_PC          0x14000000
  61 #define REG_PS          0x080000e6
  62 #define REG_WB          0x08000048
  63 #define REG_WS          0x08000049
  64 #define REG_LBEG        0x08000000
  65 #define REG_LEND        0x08000001
  66 #define REG_LCOUNT      0x08000002
  67 #define REG_SAR         0x08000003
  68 #define REG_DEPC        0x080000c0
  69 #define REG_EXCCAUSE    0x080000e8
  70 #define REG_EXCVADDR    0x080000ee
  71 #define SYSCALL_NR      0x1
  72
  73 #define AR_REGNO_TO_A_REGNO(ar, wb) (ar - wb*4) & ~(XCHAL_NUM_AREGS - 1)
  74
  75 /* Other PTRACE_ values defined in <linux/ptrace.h> using values 0-9,16,17,24 */
  76
  77 #define PTRACE_GETREGS            12
  78 #define PTRACE_SETREGS            13
  79 #define PTRACE_GETFPREGS          14
  80 #define PTRACE_SETFPREGS          15
  81 #define PTRACE_GETFPREGSIZE       18
  82
  83 #ifndef __ASSEMBLY__
  84
  85 /*
  86  * This struct defines the way the registers are stored on the
  87  * kernel stack during a system call or other kernel entry.
  88  */
  89 struct pt_regs {
  90         unsigned long pc;               /*   4 */
  91         unsigned long ps;               /*   8 */
  92         unsigned long depc;             /*  12 */
  93         unsigned long exccause;         /*  16 */
  94         unsigned long excvaddr;         /*  20 */
  95         unsigned long debugcause;       /*  24 */
  96         unsigned long wmask;            /*  28 */
  97         unsigned long lbeg;             /*  32 */
  98         unsigned long lend;             /*  36 */
  99         unsigned long lcount;           /*  40 */
 100         unsigned long sar;              /*  44 */
 101         unsigned long windowbase;       /*  48 */
 102         unsigned long windowstart;      /*  52 */
 103         unsigned long syscall;          /*  56 */
 104         int reserved[2];                /*  64 */
 105
 106         /* Make sure the areg field is 16 bytes aligned. */
 107         int align[0] __attribute__ ((aligned(16)));
 108
 109         /* current register frame.
 110          * Note: The ESF for kernel exceptions ends after 16 registers!
 111          */
 112         unsigned long areg[16];         /* 128 (64) */
 113 };
 114
 115 #ifdef __KERNEL__
 116 # define task_pt_regs(tsk) ((struct pt_regs*) \
 117   (task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
 118 # define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
 119 # define instruction_pointer(regs) ((regs)->pc)
 120 extern void show_regs(struct pt_regs *);
 121
 122 # ifndef CONFIG_SMP
 123 #  define profile_pc(regs) instruction_pointer(regs)
 124 # endif
 125 #endif /* __KERNEL__ */
 126
 127 #else   /* __ASSEMBLY__ */
 128
 129 #ifdef __KERNEL__
 130 # include <asm/asm-offsets.h>
 131 #define PT_REGS_OFFSET    (KERNEL_STACK_SIZE - PT_USER_SIZE)
 132 #endif
 133
 134 #endif  /* !__ASSEMBLY__ */
 135 #endif  /* _XTENSA_PTRACE_H */