gnu/dist/gdb6/gdb/gdbserver/linux-cris-low.c

   1 /* GNU/Linux/CRIS specific low level interface, for the remote server for GDB.
   2    Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   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 as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include "server.h"
  23 #include "linux-low.h"
  24 #include <sys/ptrace.h>
  25
  26 /* CRISv10 */
  27 #define cris_num_regs 32
  28
  29 /* Locations need to match <include/asm/arch/ptrace.h>.  */
  30 static int cris_regmap[] = {
  31   15*4, 14*4, 13*4, 12*4,
  32   11*4, 10*4, 9*4, 8*4,
  33   7*4, 6*4, 5*4, 4*4,
  34   3*4, 2*4, 23*4, 19*4,
  35
  36   -1, -1, -1, -1,
  37   -1, 17*4, -1, 16*4,
  38   -1, -1, -1, 18*4,
  39   -1, 17*4, -1, -1
  40
  41 };
  42
  43 static int
  44 cris_cannot_store_register (int regno)
  45 {
  46   if (cris_regmap[regno] == -1)
  47     return 1;
  48
  49   return (regno >= cris_num_regs);
  50 }
  51
  52 static int
  53 cris_cannot_fetch_register (int regno)
  54 {
  55   if (cris_regmap[regno] == -1)
  56     return 1;
  57
  58   return (regno >= cris_num_regs);
  59 }
  60
  61 extern int debug_threads;
  62
  63 static CORE_ADDR
  64 cris_get_pc (void)
  65 {
  66   unsigned long pc;
  67   collect_register_by_name ("pc", &pc);
  68   if (debug_threads)
  69     fprintf (stderr, "stop pc is %08lx\n", pc);
  70   return pc;
  71 }
  72
  73 static void
  74 cris_set_pc (CORE_ADDR pc)
  75 {
  76   unsigned long newpc = pc;
  77   supply_register_by_name ("pc", &newpc);
  78 }
  79
  80 static const unsigned short cris_breakpoint = 0xe938;
  81 #define cris_breakpoint_len 2
  82
  83 static int
  84 cris_breakpoint_at (CORE_ADDR where)
  85 {
  86   unsigned short insn;
  87
  88   (*the_target->read_memory) (where, (unsigned char *) &insn,
  89                               cris_breakpoint_len);
  90   if (insn == cris_breakpoint)
  91     return 1;
  92
  93   /* If necessary, recognize more trap instructions here.  GDB only uses the
  94      one.  */
  95   return 0;
  96 }
  97
  98 /* We only place breakpoints in empty marker functions, and thread locking
  99    is outside of the function.  So rather than importing software single-step,
 100    we can just run until exit.  */
 101 static CORE_ADDR
 102 cris_reinsert_addr (void)
 103 {
 104   unsigned long pc;
 105   collect_register_by_name ("srp", &pc);
 106   return pc;
 107 }
 108
 109 struct linux_target_ops the_low_target = {
 110   cris_num_regs,
 111   cris_regmap,
 112   cris_cannot_fetch_register,
 113   cris_cannot_store_register,
 114   cris_get_pc,
 115   cris_set_pc,
 116   (const unsigned char *) &cris_breakpoint,
 117   cris_breakpoint_len,
 118   cris_reinsert_addr,
 119   0,
 120   cris_breakpoint_at,
 121   0,
 122   0,
 123   0,
 124   0,
 125 };