linux-arm-low.c   [plain text]

/* GNU/Linux/ARM specific low level interface, for the remote server for GDB.
   Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002
   Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include "server.h"
#include "linux-low.h"

#ifdef HAVE_SYS_REG_H
#include <sys/reg.h>
#endif

#define arm_num_regs 26

static int arm_regmap[] = {
  0, 4, 8, 12, 16, 20, 24, 28,
  32, 36, 40, 44, 48, 52, 56, 60,
  -1, -1, -1, -1, -1, -1, -1, -1, -1,
  64
};

static int
arm_cannot_store_register (int regno)
{
  return (regno >= arm_num_regs);
}

static int
arm_cannot_fetch_register (int regno)
{
  return (regno >= arm_num_regs);
}

static CORE_ADDR
arm_get_pc ()
{
  unsigned long pc;
  collect_register_by_name ("pc", &pc);
  return pc;
}

static void
arm_set_pc (CORE_ADDR pc)
{
  unsigned long newpc = pc;
  supply_register_by_name ("pc", &newpc);
}

/* Correct in either endianness.  We do not support Thumb yet.  */
static const unsigned long arm_breakpoint = 0xef9f0001;
#define arm_breakpoint_len 4

static int
arm_breakpoint_at (CORE_ADDR where)
{
  unsigned long insn;

  (*the_target->read_memory) (where, (char *) &insn, 4);
  if (insn == arm_breakpoint)
    return 1;

  /* If necessary, recognize more trap instructions here.  GDB only uses the
     one.  */
  return 0;
}

struct linux_target_ops the_low_target = {
  arm_num_regs,
  arm_regmap,
  arm_cannot_fetch_register,
  arm_cannot_store_register,
  arm_get_pc,
  arm_set_pc,
  (const char *) &arm_breakpoint,
  arm_breakpoint_len,
  NULL,
  0,
  arm_breakpoint_at,
};