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    2007, 2008 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 3 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "server.h"
  21 #include "linux-low.h"
  22 #include <sys/ptrace.h>
  23
  24 /* CRISv10 */
  25 #define cris_num_regs 32
  26
  27 /* Locations need to match <include/asm/arch/ptrace.h>.  */
  28 static int cris_regmap[] = {
  29   15*4, 14*4, 13*4, 12*4,
  30   11*4, 10*4, 9*4, 8*4,
  31   7*4, 6*4, 5*4, 4*4,
  32   3*4, 2*4, 23*4, 19*4,
  33
  34   -1, -1, -1, -1,
  35   -1, 17*4, -1, 16*4,
  36   -1, -1, -1, 18*4,
  37   -1, 17*4, -1, -1
  38
  39 };
  40
  41 static int
  42 cris_cannot_store_register (int regno)
  43 {
  44   if (cris_regmap[regno] == -1)
  45     return 1;
  46
  47   return (regno >= cris_num_regs);
  48 }
  49
  50 static int
  51 cris_cannot_fetch_register (int regno)
  52 {
  53   if (cris_regmap[regno] == -1)
  54     return 1;
  55
  56   return (regno >= cris_num_regs);
  57 }
  58
  59 extern int debug_threads;
  60
  61 static CORE_ADDR
  62 cris_get_pc (void)
  63 {
  64   unsigned long pc;
  65   collect_register_by_name ("pc", &pc);
  66   if (debug_threads)
  67     fprintf (stderr, "stop pc is %08lx\n", pc);
  68   return pc;
  69 }
  70
  71 static void
  72 cris_set_pc (CORE_ADDR pc)
  73 {
  74   unsigned long newpc = pc;
  75   supply_register_by_name ("pc", &newpc);
  76 }
  77
  78 static const unsigned short cris_breakpoint = 0xe938;
  79 #define cris_breakpoint_len 2
  80
  81 static int
  82 cris_breakpoint_at (CORE_ADDR where)
  83 {
  84   unsigned short insn;
  85
  86   (*the_target->read_memory) (where, (unsigned char *) &insn,
  87                               cris_breakpoint_len);
  88   if (insn == cris_breakpoint)
  89     return 1;
  90
  91   /* If necessary, recognize more trap instructions here.  GDB only uses the
  92      one.  */
  93   return 0;
  94 }
  95
  96 /* We only place breakpoints in empty marker functions, and thread locking
  97    is outside of the function.  So rather than importing software single-step,
  98    we can just run until exit.  */
  99 static CORE_ADDR
 100 cris_reinsert_addr (void)
 101 {
 102   unsigned long pc;
 103   collect_register_by_name ("srp", &pc);
 104   return pc;
 105 }
 106
 107 struct linux_target_ops the_low_target = {
 108   cris_num_regs,
 109   cris_regmap,
 110   cris_cannot_fetch_register,
 111   cris_cannot_store_register,
 112   cris_get_pc,
 113   cris_set_pc,
 114   (const unsigned char *) &cris_breakpoint,
 115   cris_breakpoint_len,
 116   cris_reinsert_addr,
 117   0,
 118   cris_breakpoint_at,
 119   0,
 120   0,
 121   0,
 122   0,
 123 };