[deliverable/binutils-gdb.git] / gdb / gdbserver / linux-mips-low.c

/* GNU/Linux/MIPS specific low level interface, for the remote server for GDB.
   Copyright (C) 1995-2013 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 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 <sys/ptrace.h>
#include <endian.h>

#include "gdb_proc_service.h"

/* Defined in auto-generated file mips-linux.c.  */
void init_registers_mips_linux (void);
extern const struct target_desc *tdesc_mips_linux;

/* Defined in auto-generated file mips-dsp-linux.c.  */
void init_registers_mips_dsp_linux (void);
extern const struct target_desc *tdesc_mips_dsp_linux;

/* Defined in auto-generated file mips64-linux.c.  */
void init_registers_mips64_linux (void);
extern const struct target_desc *tdesc_mips64_linux;

/* Defined in auto-generated file mips64-dsp-linux.c.  */
void init_registers_mips64_dsp_linux (void);
extern const struct target_desc *tdesc_mips64_dsp_linux;

#ifdef __mips64
#define tdesc_mips_linux tdesc_mips64_linux
#define tdesc_mips_dsp_linux tdesc_mips64_dsp_linux
#endif

#ifndef PTRACE_GET_THREAD_AREA
#define PTRACE_GET_THREAD_AREA 25
#endif

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

#define mips_num_regs 73
#define mips_dsp_num_regs 80

#include <asm/ptrace.h>

#ifndef DSP_BASE
#define DSP_BASE 71
#define DSP_CONTROL 77
#endif

union mips_register
{
  unsigned char buf[8];

  /* Deliberately signed, for proper sign extension.  */
  int reg32;
  long long reg64;
};

/* Return the ptrace ``address'' of register REGNO. */

#define mips_base_regs							\
  -1,  1,  2,  3,  4,  5,  6,  7,					\
  8,  9,  10, 11, 12, 13, 14, 15,					\
  16, 17, 18, 19, 20, 21, 22, 23,					\
  24, 25, 26, 27, 28, 29, 30, 31,					\
									\
  -1, MMLO, MMHI, BADVADDR, CAUSE, PC,					\
									\
  FPR_BASE,      FPR_BASE + 1,  FPR_BASE + 2,  FPR_BASE + 3,		\
  FPR_BASE + 4,  FPR_BASE + 5,  FPR_BASE + 6,  FPR_BASE + 7,		\
  FPR_BASE + 8,  FPR_BASE + 9,  FPR_BASE + 10, FPR_BASE + 11,		\
  FPR_BASE + 12, FPR_BASE + 13, FPR_BASE + 14, FPR_BASE + 15,		\
  FPR_BASE + 16, FPR_BASE + 17, FPR_BASE + 18, FPR_BASE + 19,		\
  FPR_BASE + 20, FPR_BASE + 21, FPR_BASE + 22, FPR_BASE + 23,		\
  FPR_BASE + 24, FPR_BASE + 25, FPR_BASE + 26, FPR_BASE + 27,		\
  FPR_BASE + 28, FPR_BASE + 29, FPR_BASE + 30, FPR_BASE + 31,		\
  FPC_CSR, FPC_EIR

#define mips_dsp_regs							\
  DSP_BASE,      DSP_BASE + 1,  DSP_BASE + 2,  DSP_BASE + 3,		\
  DSP_BASE + 4,  DSP_BASE + 5,						\
  DSP_CONTROL

static int mips_regmap[mips_num_regs] = {
  mips_base_regs,
  0
};

static int mips_dsp_regmap[mips_dsp_num_regs] = {
  mips_base_regs,
  mips_dsp_regs,
  0
};

/* DSP registers are not in any regset and can only be accessed
   individually.  */

static unsigned char mips_dsp_regset_bitmap[(mips_dsp_num_regs + 7) / 8] = {
  0xfe, 0xff, 0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0xff, 0x80
};

static int have_dsp = -1;

/* Try peeking at an arbitrarily chosen DSP register and pick the available
   user register set accordingly.  */

static const struct target_desc *
mips_read_description (void)
{
  if (have_dsp < 0)
    {
      int pid = lwpid_of (get_thread_lwp (current_inferior));

      ptrace (PTRACE_PEEKUSER, pid, DSP_CONTROL, 0);
      switch (errno)
	{
	case 0:
	  have_dsp = 1;
	  break;
	case EIO:
	  have_dsp = 0;
	  break;
	default:
	  perror_with_name ("ptrace");
	  break;
	}
    }

  return have_dsp ? tdesc_mips_dsp_linux : tdesc_mips_linux;
}

static void
mips_arch_setup (void)
{
  current_process ()->tdesc = mips_read_description ();
}

static struct usrregs_info *
get_usrregs_info (void)
{
  const struct regs_info *regs_info = the_low_target.regs_info ();

  return regs_info->usrregs;
}

/* From mips-linux-nat.c.  */

/* Pseudo registers can not be read.  ptrace does not provide a way to
   read (or set) PS_REGNUM, and there's no point in reading or setting
   ZERO_REGNUM.  We also can not set BADVADDR, CAUSE, or FCRIR via
   ptrace().  */

static int
mips_cannot_fetch_register (int regno)
{
  const struct target_desc *tdesc;

  if (get_usrregs_info ()->regmap[regno] == -1)
    return 1;

  tdesc = current_process ()->tdesc;

  if (find_regno (tdesc, "r0") == regno)
    return 1;

  return 0;
}

static int
mips_cannot_store_register (int regno)
{
  const struct target_desc *tdesc;

  if (get_usrregs_info ()->regmap[regno] == -1)
    return 1;

  tdesc = current_process ()->tdesc;

  if (find_regno (tdesc, "r0") == regno)
    return 1;

  if (find_regno (tdesc, "cause") == regno)
    return 1;

  if (find_regno (tdesc, "badvaddr") == regno)
    return 1;

  if (find_regno (tdesc, "fir") == regno)
    return 1;

  return 0;
}

static CORE_ADDR
mips_get_pc (struct regcache *regcache)
{
  union mips_register pc;
  collect_register_by_name (regcache, "pc", pc.buf);
  return register_size (regcache->tdesc, 0) == 4 ? pc.reg32 : pc.reg64;
}

static void
mips_set_pc (struct regcache *regcache, CORE_ADDR pc)
{
  union mips_register newpc;
  if (register_size (regcache->tdesc, 0) == 4)
    newpc.reg32 = pc;
  else
    newpc.reg64 = pc;

  supply_register_by_name (regcache, "pc", newpc.buf);
}

/* Correct in either endianness.  */
static const unsigned int mips_breakpoint = 0x0005000d;
#define mips_breakpoint_len 4

/* We only place breakpoints in empty marker functions, and thread locking
   is outside of the function.  So rather than importing software single-step,
   we can just run until exit.  */
static CORE_ADDR
mips_reinsert_addr (void)
{
  struct regcache *regcache = get_thread_regcache (current_inferior, 1);
  union mips_register ra;
  collect_register_by_name (regcache, "r31", ra.buf);
  return register_size (regcache->tdesc, 0) == 4 ? ra.reg32 : ra.reg64;
}

static int
mips_breakpoint_at (CORE_ADDR where)
{
  unsigned int insn;

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

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

/* Fetch the thread-local storage pointer for libthread_db.  */

ps_err_e
ps_get_thread_area (const struct ps_prochandle *ph,
		    lwpid_t lwpid, int idx, void **base)
{
  if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
    return PS_ERR;

  /* IDX is the bias from the thread pointer to the beginning of the
     thread descriptor.  It has to be subtracted due to implementation
     quirks in libthread_db.  */
  *base = (void *) ((char *)*base - idx);

  return PS_OK;
}

#ifdef HAVE_PTRACE_GETREGS

static void
mips_collect_register (struct regcache *regcache,
		       int use_64bit, int regno, union mips_register *reg)
{
  union mips_register tmp_reg;

  if (use_64bit)
    {
      collect_register (regcache, regno, &tmp_reg.reg64);
      *reg = tmp_reg;
    }
  else
    {
      collect_register (regcache, regno, &tmp_reg.reg32);
      reg->reg64 = tmp_reg.reg32;
    }
}

static void
mips_supply_register (struct regcache *regcache,
		      int use_64bit, int regno, const union mips_register *reg)
{
  int offset = 0;

  /* For big-endian 32-bit targets, ignore the high four bytes of each
     eight-byte slot.  */
  if (__BYTE_ORDER == __BIG_ENDIAN && !use_64bit)
    offset = 4;

  supply_register (regcache, regno, reg->buf + offset);
}

static void
mips_collect_register_32bit (struct regcache *regcache,
			     int use_64bit, int regno, unsigned char *buf)
{
  union mips_register tmp_reg;
  int reg32;

  mips_collect_register (regcache, use_64bit, regno, &tmp_reg);
  reg32 = tmp_reg.reg64;
  memcpy (buf, &reg32, 4);
}

static void
mips_supply_register_32bit (struct regcache *regcache,
			    int use_64bit, int regno, const unsigned char *buf)
{
  union mips_register tmp_reg;
  int reg32;

  memcpy (&reg32, buf, 4);
  tmp_reg.reg64 = reg32;
  mips_supply_register (regcache, use_64bit, regno, &tmp_reg);
}

static void
mips_fill_gregset (struct regcache *regcache, void *buf)
{
  union mips_register *regset = buf;
  int i, use_64bit;
  const struct target_desc *tdesc = regcache->tdesc;

  use_64bit = (register_size (tdesc, 0) == 8);

  for (i = 1; i < 32; i++)
    mips_collect_register (regcache, use_64bit, i, regset + i);

  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "lo"), regset + 32);
  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "hi"), regset + 33);
  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "pc"), regset + 34);
  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "badvaddr"), regset + 35);
  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "status"), regset + 36);
  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "cause"), regset + 37);

  mips_collect_register (regcache, use_64bit,
			 find_regno (tdesc, "restart"), regset + 0);
}

static void
mips_store_gregset (struct regcache *regcache, const void *buf)
{
  const union mips_register *regset = buf;
  int i, use_64bit;

  use_64bit = (register_size (regcache->tdesc, 0) == 8);

  for (i = 0; i < 32; i++)
    mips_supply_register (regcache, use_64bit, i, regset + i);

  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "lo"), regset + 32);
  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "hi"), regset + 33);
  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "pc"), regset + 34);
  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "badvaddr"), regset + 35);
  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "status"), regset + 36);
  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "cause"), regset + 37);

  mips_supply_register (regcache, use_64bit,
			find_regno (regcache->tdesc, "restart"), regset + 0);
}

static void
mips_fill_fpregset (struct regcache *regcache, void *buf)
{
  union mips_register *regset = buf;
  int i, use_64bit, first_fp, big_endian;

  use_64bit = (register_size (regcache->tdesc, 0) == 8);
  first_fp = find_regno (regcache->tdesc, "f0");
  big_endian = (__BYTE_ORDER == __BIG_ENDIAN);

  /* See GDB for a discussion of this peculiar layout.  */
  for (i = 0; i < 32; i++)
    if (use_64bit)
      collect_register (regcache, first_fp + i, regset[i].buf);
    else
      collect_register (regcache, first_fp + i,
			regset[i & ~1].buf + 4 * (big_endian != (i & 1)));

  mips_collect_register_32bit (regcache, use_64bit,
			       find_regno (regcache->tdesc, "fcsr"), regset[32].buf);
  mips_collect_register_32bit (regcache, use_64bit,
			       find_regno (regcache->tdesc, "fir"),
			       regset[32].buf + 4);
}

static void
mips_store_fpregset (struct regcache *regcache, const void *buf)
{
  const union mips_register *regset = buf;
  int i, use_64bit, first_fp, big_endian;

  use_64bit = (register_size (regcache->tdesc, 0) == 8);
  first_fp = find_regno (regcache->tdesc, "f0");
  big_endian = (__BYTE_ORDER == __BIG_ENDIAN);

  /* See GDB for a discussion of this peculiar layout.  */
  for (i = 0; i < 32; i++)
    if (use_64bit)
      supply_register (regcache, first_fp + i, regset[i].buf);
    else
      supply_register (regcache, first_fp + i,
		       regset[i & ~1].buf + 4 * (big_endian != (i & 1)));

  mips_supply_register_32bit (regcache, use_64bit,
			      find_regno (regcache->tdesc, "fcsr"),
			      regset[32].buf);
  mips_supply_register_32bit (regcache, use_64bit,
			      find_regno (regcache->tdesc, "fir"),
			      regset[32].buf + 4);
}
#endif /* HAVE_PTRACE_GETREGS */

static struct regset_info mips_regsets[] = {
#ifdef HAVE_PTRACE_GETREGS
  { PTRACE_GETREGS, PTRACE_SETREGS, 0, 38 * 8, GENERAL_REGS,
    mips_fill_gregset, mips_store_gregset },
  { PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, 33 * 8, FP_REGS,
    mips_fill_fpregset, mips_store_fpregset },
#endif /* HAVE_PTRACE_GETREGS */
  { 0, 0, 0, -1, -1, NULL, NULL }
};

static struct regsets_info mips_regsets_info =
  {
    mips_regsets, /* regsets */
    0, /* num_regsets */
    NULL, /* disabled_regsets */
  };

static struct usrregs_info mips_dsp_usrregs_info =
  {
    mips_dsp_num_regs,
    mips_dsp_regmap,
  };

static struct usrregs_info mips_usrregs_info =
  {
    mips_num_regs,
    mips_regmap,
  };

static struct regs_info dsp_regs_info =
  {
    mips_dsp_regset_bitmap,
    &mips_dsp_usrregs_info,
    &mips_regsets_info
  };

static struct regs_info regs_info =
  {
    NULL, /* regset_bitmap */
    &mips_usrregs_info,
    &mips_regsets_info
  };

static const struct regs_info *
mips_regs_info (void)
{
  if (have_dsp)
    return &dsp_regs_info;
  else
    return &regs_info;
}

struct linux_target_ops the_low_target = {
  mips_arch_setup,
  mips_regs_info,
  mips_cannot_fetch_register,
  mips_cannot_store_register,
  NULL, /* fetch_register */
  mips_get_pc,
  mips_set_pc,
  (const unsigned char *) &mips_breakpoint,
  mips_breakpoint_len,
  mips_reinsert_addr,
  0,
  mips_breakpoint_at,
};

void
initialize_low_arch (void)
{
  /* Initialize the Linux target descriptions.  */
  init_registers_mips_linux ();
  init_registers_mips_dsp_linux ();
  init_registers_mips64_linux ();
  init_registers_mips64_dsp_linux ();

  initialize_regsets_info (&mips_regsets_info);
}
Commit	Line	Data
	1	/* GNU/Linux/MIPS specific low level interface, for the remote server for GDB.
	2	Copyright (C) 1995-2013 Free Software Foundation, Inc.
	3
	4	This file is part of GDB.
	5
	6	This program is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 3 of the License, or
	9	(at your option) any later version.
	10
	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	18
	19	#include "server.h"
	20	#include "linux-low.h"
	21
	22	#include <sys/ptrace.h>
	23	#include <endian.h>
	24
	25	#include "gdb_proc_service.h"
	26
	27	/* Defined in auto-generated file mips-linux.c. */
	28	void init_registers_mips_linux (void);
	29	extern const struct target_desc *tdesc_mips_linux;
	30
	31	/* Defined in auto-generated file mips-dsp-linux.c. */
	32	void init_registers_mips_dsp_linux (void);
	33	extern const struct target_desc *tdesc_mips_dsp_linux;
	34
	35	/* Defined in auto-generated file mips64-linux.c. */
	36	void init_registers_mips64_linux (void);
	37	extern const struct target_desc *tdesc_mips64_linux;
	38
	39	/* Defined in auto-generated file mips64-dsp-linux.c. */
	40	void init_registers_mips64_dsp_linux (void);
	41	extern const struct target_desc *tdesc_mips64_dsp_linux;
	42
	43	#ifdef __mips64
	44	#define tdesc_mips_linux tdesc_mips64_linux
	45	#define tdesc_mips_dsp_linux tdesc_mips64_dsp_linux
	46	#endif
	47
	48	#ifndef PTRACE_GET_THREAD_AREA
	49	#define PTRACE_GET_THREAD_AREA 25
	50	#endif
	51
	52	#ifdef HAVE_SYS_REG_H
	53	#include <sys/reg.h>
	54	#endif
	55
	56	#define mips_num_regs 73
	57	#define mips_dsp_num_regs 80
	58
	59	#include <asm/ptrace.h>
	60
	61	#ifndef DSP_BASE
	62	#define DSP_BASE 71
	63	#define DSP_CONTROL 77
	64	#endif
	65
	66	union mips_register
	67	{
	68	unsigned char buf[8];
	69
	70	/* Deliberately signed, for proper sign extension. */
	71	int reg32;
	72	long long reg64;
	73	};
	74
	75	/* Return the ptrace ``address'' of register REGNO. */
	76
	77	#define mips_base_regs \
	78	-1, 1, 2, 3, 4, 5, 6, 7, \
	79	8, 9, 10, 11, 12, 13, 14, 15, \
	80	16, 17, 18, 19, 20, 21, 22, 23, \
	81	24, 25, 26, 27, 28, 29, 30, 31, \
	82	\
	83	-1, MMLO, MMHI, BADVADDR, CAUSE, PC, \
	84	\
	85	FPR_BASE, FPR_BASE + 1, FPR_BASE + 2, FPR_BASE + 3, \
	86	FPR_BASE + 4, FPR_BASE + 5, FPR_BASE + 6, FPR_BASE + 7, \
	87	FPR_BASE + 8, FPR_BASE + 9, FPR_BASE + 10, FPR_BASE + 11, \
	88	FPR_BASE + 12, FPR_BASE + 13, FPR_BASE + 14, FPR_BASE + 15, \
	89	FPR_BASE + 16, FPR_BASE + 17, FPR_BASE + 18, FPR_BASE + 19, \
	90	FPR_BASE + 20, FPR_BASE + 21, FPR_BASE + 22, FPR_BASE + 23, \
	91	FPR_BASE + 24, FPR_BASE + 25, FPR_BASE + 26, FPR_BASE + 27, \
	92	FPR_BASE + 28, FPR_BASE + 29, FPR_BASE + 30, FPR_BASE + 31, \
	93	FPC_CSR, FPC_EIR
	94
	95	#define mips_dsp_regs \
	96	DSP_BASE, DSP_BASE + 1, DSP_BASE + 2, DSP_BASE + 3, \
	97	DSP_BASE + 4, DSP_BASE + 5, \
	98	DSP_CONTROL
	99
	100	static int mips_regmap[mips_num_regs] = {
	101	mips_base_regs,
	102	0
	103	};
	104
	105	static int mips_dsp_regmap[mips_dsp_num_regs] = {
	106	mips_base_regs,
	107	mips_dsp_regs,
	108	0
	109	};
	110
	111	/* DSP registers are not in any regset and can only be accessed
	112	individually. */
	113
	114	static unsigned char mips_dsp_regset_bitmap[(mips_dsp_num_regs + 7) / 8] = {
	115	0xfe, 0xff, 0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0xff, 0x80
	116	};
	117
	118	static int have_dsp = -1;
	119
	120	/* Try peeking at an arbitrarily chosen DSP register and pick the available
	121	user register set accordingly. */
	122
	123	static const struct target_desc *
	124	mips_read_description (void)
	125	{
	126	if (have_dsp < 0)
	127	{
	128	int pid = lwpid_of (get_thread_lwp (current_inferior));
	129
	130	ptrace (PTRACE_PEEKUSER, pid, DSP_CONTROL, 0);
	131	switch (errno)
	132	{
	133	case 0:
	134	have_dsp = 1;
	135	break;
	136	case EIO:
	137	have_dsp = 0;
	138	break;
	139	default:
	140	perror_with_name ("ptrace");
	141	break;
	142	}
	143	}
	144
	145	return have_dsp ? tdesc_mips_dsp_linux : tdesc_mips_linux;
	146	}
	147
	148	static void
	149	mips_arch_setup (void)
	150	{
	151	current_process ()->tdesc = mips_read_description ();
	152	}
	153
	154	static struct usrregs_info *
	155	get_usrregs_info (void)
	156	{
	157	const struct regs_info *regs_info = the_low_target.regs_info ();
	158
	159	return regs_info->usrregs;
	160	}
	161
	162	/* From mips-linux-nat.c. */
	163
	164	/* Pseudo registers can not be read. ptrace does not provide a way to
	165	read (or set) PS_REGNUM, and there's no point in reading or setting
	166	ZERO_REGNUM. We also can not set BADVADDR, CAUSE, or FCRIR via
	167	ptrace(). */
	168
	169	static int
	170	mips_cannot_fetch_register (int regno)
	171	{
	172	const struct target_desc *tdesc;
	173
	174	if (get_usrregs_info ()->regmap[regno] == -1)
	175	return 1;
	176
	177	tdesc = current_process ()->tdesc;
	178
	179	if (find_regno (tdesc, "r0") == regno)
	180	return 1;
	181
	182	return 0;
	183	}
	184
	185	static int
	186	mips_cannot_store_register (int regno)
	187	{
	188	const struct target_desc *tdesc;
	189
	190	if (get_usrregs_info ()->regmap[regno] == -1)
	191	return 1;
	192
	193	tdesc = current_process ()->tdesc;
	194
	195	if (find_regno (tdesc, "r0") == regno)
	196	return 1;
	197
	198	if (find_regno (tdesc, "cause") == regno)
	199	return 1;
	200
	201	if (find_regno (tdesc, "badvaddr") == regno)
	202	return 1;
	203
	204	if (find_regno (tdesc, "fir") == regno)
	205	return 1;
	206
	207	return 0;
	208	}
	209
	210	static CORE_ADDR
	211	mips_get_pc (struct regcache *regcache)
	212	{
	213	union mips_register pc;
	214	collect_register_by_name (regcache, "pc", pc.buf);
	215	return register_size (regcache->tdesc, 0) == 4 ? pc.reg32 : pc.reg64;
	216	}
	217
	218	static void
	219	mips_set_pc (struct regcache *regcache, CORE_ADDR pc)
	220	{
	221	union mips_register newpc;
	222	if (register_size (regcache->tdesc, 0) == 4)
	223	newpc.reg32 = pc;
	224	else
	225	newpc.reg64 = pc;
	226
	227	supply_register_by_name (regcache, "pc", newpc.buf);
	228	}
	229
	230	/* Correct in either endianness. */
	231	static const unsigned int mips_breakpoint = 0x0005000d;
	232	#define mips_breakpoint_len 4
	233
	234	/* We only place breakpoints in empty marker functions, and thread locking
	235	is outside of the function. So rather than importing software single-step,
	236	we can just run until exit. */
	237	static CORE_ADDR
	238	mips_reinsert_addr (void)
	239	{
	240	struct regcache *regcache = get_thread_regcache (current_inferior, 1);
	241	union mips_register ra;
	242	collect_register_by_name (regcache, "r31", ra.buf);
	243	return register_size (regcache->tdesc, 0) == 4 ? ra.reg32 : ra.reg64;
	244	}
	245
	246	static int
	247	mips_breakpoint_at (CORE_ADDR where)
	248	{
	249	unsigned int insn;
	250
	251	(the_target->read_memory) (where, (unsigned char ) &insn, 4);
	252	if (insn == mips_breakpoint)
	253	return 1;
	254
	255	/* If necessary, recognize more trap instructions here. GDB only uses the
	256	one. */
	257	return 0;
	258	}
	259
	260	/* Fetch the thread-local storage pointer for libthread_db. */
	261
	262	ps_err_e
	263	ps_get_thread_area (const struct ps_prochandle *ph,
	264	lwpid_t lwpid, int idx, void **base)
	265	{
	266	if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
	267	return PS_ERR;
	268
	269	/* IDX is the bias from the thread pointer to the beginning of the
	270	thread descriptor. It has to be subtracted due to implementation
	271	quirks in libthread_db. */
	272	base = (void ) ((char )base - idx);
	273
	274	return PS_OK;
	275	}
	276
	277	#ifdef HAVE_PTRACE_GETREGS
	278
	279	static void
	280	mips_collect_register (struct regcache *regcache,
	281	int use_64bit, int regno, union mips_register *reg)
	282	{
	283	union mips_register tmp_reg;
	284
	285	if (use_64bit)
	286	{
	287	collect_register (regcache, regno, &tmp_reg.reg64);
	288	*reg = tmp_reg;
	289	}
	290	else
	291	{
	292	collect_register (regcache, regno, &tmp_reg.reg32);
	293	reg->reg64 = tmp_reg.reg32;
	294	}
	295	}
	296
	297	static void
	298	mips_supply_register (struct regcache *regcache,
	299	int use_64bit, int regno, const union mips_register *reg)
	300	{
	301	int offset = 0;
	302
	303	/* For big-endian 32-bit targets, ignore the high four bytes of each
	304	eight-byte slot. */
	305	if (__BYTE_ORDER == __BIG_ENDIAN && !use_64bit)
	306	offset = 4;
	307
	308	supply_register (regcache, regno, reg->buf + offset);
	309	}
	310
	311	static void
	312	mips_collect_register_32bit (struct regcache *regcache,
	313	int use_64bit, int regno, unsigned char *buf)
	314	{
	315	union mips_register tmp_reg;
	316	int reg32;
	317
	318	mips_collect_register (regcache, use_64bit, regno, &tmp_reg);
	319	reg32 = tmp_reg.reg64;
	320	memcpy (buf, &reg32, 4);
	321	}
	322
	323	static void
	324	mips_supply_register_32bit (struct regcache *regcache,
	325	int use_64bit, int regno, const unsigned char *buf)
	326	{
	327	union mips_register tmp_reg;
	328	int reg32;
	329
	330	memcpy (&reg32, buf, 4);
	331	tmp_reg.reg64 = reg32;
	332	mips_supply_register (regcache, use_64bit, regno, &tmp_reg);
	333	}
	334
	335	static void
	336	mips_fill_gregset (struct regcache regcache, void buf)
	337	{
	338	union mips_register *regset = buf;
	339	int i, use_64bit;
	340	const struct target_desc *tdesc = regcache->tdesc;
	341
	342	use_64bit = (register_size (tdesc, 0) == 8);
	343
	344	for (i = 1; i < 32; i++)
	345	mips_collect_register (regcache, use_64bit, i, regset + i);
	346
	347	mips_collect_register (regcache, use_64bit,
	348	find_regno (tdesc, "lo"), regset + 32);
	349	mips_collect_register (regcache, use_64bit,
	350	find_regno (tdesc, "hi"), regset + 33);
	351	mips_collect_register (regcache, use_64bit,
	352	find_regno (tdesc, "pc"), regset + 34);
	353	mips_collect_register (regcache, use_64bit,
	354	find_regno (tdesc, "badvaddr"), regset + 35);
	355	mips_collect_register (regcache, use_64bit,
	356	find_regno (tdesc, "status"), regset + 36);
	357	mips_collect_register (regcache, use_64bit,
	358	find_regno (tdesc, "cause"), regset + 37);
	359
	360	mips_collect_register (regcache, use_64bit,
	361	find_regno (tdesc, "restart"), regset + 0);
	362	}
	363
	364	static void
	365	mips_store_gregset (struct regcache regcache, const void buf)
	366	{
	367	const union mips_register *regset = buf;
	368	int i, use_64bit;
	369
	370	use_64bit = (register_size (regcache->tdesc, 0) == 8);
	371
	372	for (i = 0; i < 32; i++)
	373	mips_supply_register (regcache, use_64bit, i, regset + i);
	374
	375	mips_supply_register (regcache, use_64bit,
	376	find_regno (regcache->tdesc, "lo"), regset + 32);
	377	mips_supply_register (regcache, use_64bit,
	378	find_regno (regcache->tdesc, "hi"), regset + 33);
	379	mips_supply_register (regcache, use_64bit,
	380	find_regno (regcache->tdesc, "pc"), regset + 34);
	381	mips_supply_register (regcache, use_64bit,
	382	find_regno (regcache->tdesc, "badvaddr"), regset + 35);
	383	mips_supply_register (regcache, use_64bit,
	384	find_regno (regcache->tdesc, "status"), regset + 36);
	385	mips_supply_register (regcache, use_64bit,
	386	find_regno (regcache->tdesc, "cause"), regset + 37);
	387
	388	mips_supply_register (regcache, use_64bit,
	389	find_regno (regcache->tdesc, "restart"), regset + 0);
	390	}
	391
	392	static void
	393	mips_fill_fpregset (struct regcache regcache, void buf)
	394	{
	395	union mips_register *regset = buf;
	396	int i, use_64bit, first_fp, big_endian;
	397
	398	use_64bit = (register_size (regcache->tdesc, 0) == 8);
	399	first_fp = find_regno (regcache->tdesc, "f0");
	400	big_endian = (__BYTE_ORDER == __BIG_ENDIAN);
	401
	402	/* See GDB for a discussion of this peculiar layout. */
	403	for (i = 0; i < 32; i++)
	404	if (use_64bit)
	405	collect_register (regcache, first_fp + i, regset[i].buf);
	406	else
	407	collect_register (regcache, first_fp + i,
	408	regset[i & ~1].buf + 4 * (big_endian != (i & 1)));
	409
	410	mips_collect_register_32bit (regcache, use_64bit,
	411	find_regno (regcache->tdesc, "fcsr"), regset[32].buf);
	412	mips_collect_register_32bit (regcache, use_64bit,
	413	find_regno (regcache->tdesc, "fir"),
	414	regset[32].buf + 4);
	415	}
	416
	417	static void
	418	mips_store_fpregset (struct regcache regcache, const void buf)
	419	{
	420	const union mips_register *regset = buf;
	421	int i, use_64bit, first_fp, big_endian;
	422
	423	use_64bit = (register_size (regcache->tdesc, 0) == 8);
	424	first_fp = find_regno (regcache->tdesc, "f0");
	425	big_endian = (__BYTE_ORDER == __BIG_ENDIAN);
	426
	427	/* See GDB for a discussion of this peculiar layout. */
	428	for (i = 0; i < 32; i++)
	429	if (use_64bit)
	430	supply_register (regcache, first_fp + i, regset[i].buf);
	431	else
	432	supply_register (regcache, first_fp + i,
	433	regset[i & ~1].buf + 4 * (big_endian != (i & 1)));
	434
	435	mips_supply_register_32bit (regcache, use_64bit,
	436	find_regno (regcache->tdesc, "fcsr"),
	437	regset[32].buf);
	438	mips_supply_register_32bit (regcache, use_64bit,
	439	find_regno (regcache->tdesc, "fir"),
	440	regset[32].buf + 4);
	441	}
	442	#endif /* HAVE_PTRACE_GETREGS */
	443
	444	static struct regset_info mips_regsets[] = {
	445	#ifdef HAVE_PTRACE_GETREGS
	446	{ PTRACE_GETREGS, PTRACE_SETREGS, 0, 38 * 8, GENERAL_REGS,
	447	mips_fill_gregset, mips_store_gregset },
	448	{ PTRACE_GETFPREGS, PTRACE_SETFPREGS, 0, 33 * 8, FP_REGS,
	449	mips_fill_fpregset, mips_store_fpregset },
	450	#endif /* HAVE_PTRACE_GETREGS */
	451	{ 0, 0, 0, -1, -1, NULL, NULL }
	452	};
	453
	454	static struct regsets_info mips_regsets_info =
	455	{
	456	mips_regsets, /* regsets */
	457	0, /* num_regsets */
	458	NULL, /* disabled_regsets */
	459	};
	460
	461	static struct usrregs_info mips_dsp_usrregs_info =
	462	{
	463	mips_dsp_num_regs,
	464	mips_dsp_regmap,
	465	};
	466
	467	static struct usrregs_info mips_usrregs_info =
	468	{
	469	mips_num_regs,
	470	mips_regmap,
	471	};
	472
	473	static struct regs_info dsp_regs_info =
	474	{
	475	mips_dsp_regset_bitmap,
	476	&mips_dsp_usrregs_info,
	477	&mips_regsets_info
	478	};
	479
	480	static struct regs_info regs_info =
	481	{
	482	NULL, /* regset_bitmap */
	483	&mips_usrregs_info,
	484	&mips_regsets_info
	485	};
	486
	487	static const struct regs_info *
	488	mips_regs_info (void)
	489	{
	490	if (have_dsp)
	491	return &dsp_regs_info;
	492	else
	493	return &regs_info;
	494	}
	495
	496	struct linux_target_ops the_low_target = {
	497	mips_arch_setup,
	498	mips_regs_info,
	499	mips_cannot_fetch_register,
	500	mips_cannot_store_register,
	501	NULL, /* fetch_register */
	502	mips_get_pc,
	503	mips_set_pc,
	504	(const unsigned char *) &mips_breakpoint,
	505	mips_breakpoint_len,
	506	mips_reinsert_addr,
	507	0,
	508	mips_breakpoint_at,
	509	};
	510
	511	void
	512	initialize_low_arch (void)
	513	{
	514	/* Initialize the Linux target descriptions. */
	515	init_registers_mips_linux ();
	516	init_registers_mips_dsp_linux ();
	517	init_registers_mips64_linux ();
	518	init_registers_mips64_dsp_linux ();
	519
	520	initialize_regsets_info (&mips_regsets_info);
	521	}