binutils-gdb/gdb/gdbserver/linux-bfin-low.c

/* GNU/Linux/BFIN specific low level interface, for the remote server for GDB.

   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011
   Free Software Foundation, Inc.

   Contributed by Analog Devices, 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 3 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, see <http://www.gnu.org/licenses/>.  */

#include "server.h"
#include "linux-low.h"
#include "libiberty.h"
#include <asm/ptrace.h>

/* Defined in auto-generated file reg-bfin.c.  */
void init_registers_bfin (void);

static int bfin_regmap[] =
{
  PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
  PT_P0, PT_P1, PT_P2, PT_P3, PT_P4, PT_P5, PT_USP, PT_FP,
  PT_I0, PT_I1, PT_I2, PT_I3, PT_M0, PT_M1, PT_M2, PT_M3,
  PT_B0, PT_B1, PT_B2, PT_B3, PT_L0, PT_L1, PT_L2, PT_L3,
  PT_A0X, PT_A0W, PT_A1X, PT_A1W, PT_ASTAT, PT_RETS,
  PT_LC0, PT_LT0, PT_LB0, PT_LC1, PT_LT1, PT_LB1,
  -1 /* PT_CYCLES */, -1 /* PT_CYCLES2 */,
  -1 /* PT_USP */, PT_SEQSTAT, PT_SYSCFG, PT_PC, PT_RETX, PT_RETN, PT_RETE,
  PT_PC,
};

#define bfin_num_regs ARRAY_SIZE (bfin_regmap)

static int
bfin_cannot_store_register (int regno)
{
  return (regno >= bfin_num_regs);
}

static int
bfin_cannot_fetch_register (int regno)
{
  return (regno >= bfin_num_regs);
}

static CORE_ADDR
bfin_get_pc (struct regcache *regcache)
{
  unsigned long pc;

  collect_register_by_name (regcache, "pc", &pc);

  return pc;
}

static void
bfin_set_pc (struct regcache *regcache, CORE_ADDR pc)
{
  unsigned long newpc = pc;

  supply_register_by_name (regcache, "pc", &newpc);
}

#define bfin_breakpoint_len 2
static const unsigned char bfin_breakpoint[bfin_breakpoint_len] = {0xa1, 0x00};

static int
bfin_breakpoint_at (CORE_ADDR where)
{
  unsigned char insn[bfin_breakpoint_len];

  read_inferior_memory(where, insn, bfin_breakpoint_len);
  if (insn[0] == bfin_breakpoint[0]
      && insn[1] == bfin_breakpoint[1])
    return 1;

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

struct linux_target_ops the_low_target = {
  init_registers_bfin,
  bfin_num_regs,
  bfin_regmap,
  bfin_cannot_fetch_register,
  bfin_cannot_store_register,
  bfin_get_pc,
  bfin_set_pc,
  bfin_breakpoint,
  bfin_breakpoint_len,
  0,
  2,
  bfin_breakpoint_at,
};