/* run front end support for arm
   Copyright (C) 1995, 1996, 1997, 2000, 2001, 2002
   Free Software Foundation, Inc.

   This file is part of ARM SIM.

   GCC 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, or (at your
   option) any later version.

   GCC 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.  */

/* This file provides the interface between the simulator and
   run.c and gdb (when the simulator is linked with gdb).
   All simulator interaction should go through this file.  */

#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <bfd.h>
#include <signal.h>
#include "callback.h"
#include "remote-sim.h"
#include "armdefs.h"
#include "armemu.h"
#include "dbg_rdi.h"
#include "ansidecl.h"
#include "sim-utils.h"

host_callback *sim_callback;

static struct ARMul_State *state;

/* Who is using the simulator.  */
static SIM_OPEN_KIND sim_kind;

/* argv[0] */
static char *myname;

/* Memory size in bytes.  */
static int mem_size = (1 << 23);

/* Non-zero to display start up banner, and maybe other things.  */
static int verbosity;

/* Non-zero to set big endian mode.  */
static int big_endian;

int stop_simulator;

static void
init ()
{
  static int done;

  if (!done)
    {
      ARMul_EmulateInit ();
      state = ARMul_NewState ();
      state->bigendSig = (big_endian ? HIGH : LOW);
      ARMul_MemoryInit (state, mem_size);
      ARMul_OSInit (state);
      ARMul_CoProInit (state);
      state->verbose = verbosity;
      done = 1;
    }
}

/* Set verbosity level of simulator.
   This is not intended to produce detailed tracing or debugging information.
   Just summaries.  */
/* FIXME: common/run.c doesn't do this yet.  */

void
sim_set_verbose (v)
     int v;
{
  verbosity = v;
}

/* Set the memory size to SIZE bytes.
   Must be called before initializing simulator.  */
/* FIXME: Rename to sim_set_mem_size.  */

void
sim_size (size)
     int size;
{
  mem_size = size;
}

void
ARMul_ConsolePrint VPARAMS ((ARMul_State * state,
			     const char * format,
			     ...))
{
  va_list ap;

  if (state->verbose)
    {
      va_start (ap, format);
      vprintf (format, ap);
      va_end (ap);
    }
}

ARMword
ARMul_Debug (state, pc, instr)
     ARMul_State * state ATTRIBUTE_UNUSED;
     ARMword       pc    ATTRIBUTE_UNUSED;
     ARMword       instr ATTRIBUTE_UNUSED;
{
  return 0;
}

int
sim_write (sd, addr, buffer, size)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     SIM_ADDR addr;
     unsigned char * buffer;
     int size;
{
  int i;

  init ();

  for (i = 0; i < size; i++)
    ARMul_SafeWriteByte (state, addr + i, buffer[i]);

  return size;
}

int
sim_read (sd, addr, buffer, size)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     SIM_ADDR addr;
     unsigned char * buffer;
     int size;
{
  int i;

  init ();

  for (i = 0; i < size; i++)
    buffer[i] = ARMul_SafeReadByte (state, addr + i);

  return size;
}

int
sim_trace (sd)
     SIM_DESC sd ATTRIBUTE_UNUSED;
{  
  (*sim_callback->printf_filtered)
    (sim_callback,
     "This simulator does not support tracing\n");
  return 1;
}

int
sim_stop (sd)
     SIM_DESC sd ATTRIBUTE_UNUSED;
{
  state->Emulate = STOP;
  stop_simulator = 1;
  return 1;
}

void
sim_resume (sd, step, siggnal)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     int step;
     int siggnal ATTRIBUTE_UNUSED;
{
  state->EndCondition = 0;
  stop_simulator = 0;

  if (step)
    {
      state->Reg[15] = ARMul_DoInstr (state);
      if (state->EndCondition == 0)
	state->EndCondition = RDIError_BreakpointReached;
    }
  else
    {
      state->NextInstr = RESUME;	/* treat as PC change */
      state->Reg[15] = ARMul_DoProg (state);
    }

  FLUSHPIPE;
}

SIM_RC
sim_create_inferior (sd, abfd, argv, env)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     struct _bfd * abfd;
     char ** argv;
     char ** env;
{
  int argvlen = 0;
  int mach;
  char **arg;

  if (abfd != NULL)
    ARMul_SetPC (state, bfd_get_start_address (abfd));
  else
    ARMul_SetPC (state, 0);	/* ??? */

  mach = bfd_get_mach (abfd);

  switch (mach)
    {
    default:
      (*sim_callback->printf_filtered)
	(sim_callback,
	 "Unknown machine type; please update sim_create_inferior.\n");
      /* fall through */

    case 0:
      /* We wouldn't set the machine type with earlier toolchains, so we
	 explicitly select a processor capable of supporting all ARMs in
	 32bit mode.  */
    case bfd_mach_arm_XScale:
      ARMul_SelectProcessor (state, ARM_v5_Prop | ARM_v5e_Prop | ARM_XScale_Prop);
      break;

    case bfd_mach_arm_5:
      if (bfd_family_coff (abfd))
	{
	  /* This is a special case in order to support COFF based ARM toolchains.
	     The COFF header does not have enough room to store all the different
	     kinds of ARM cpu, so the XScale, v5T and v5TE architectures all default
	     to v5.  (See coff_set_flags() in bdf/coffcode.h).  So if we see a v5
	     machine type here, we assume it could be any of the above architectures
	     and so select the most feature-full.  */
	  ARMul_SelectProcessor (state, ARM_v5_Prop | ARM_v5e_Prop | ARM_XScale_Prop);
	  break;
	}
      /* Otherwise drop through.  */

    case bfd_mach_arm_5T:
      ARMul_SelectProcessor (state, ARM_v5_Prop);
      break;

    case bfd_mach_arm_5TE:
      ARMul_SelectProcessor (state, ARM_v5_Prop | ARM_v5e_Prop);
      break;

    case bfd_mach_arm_4:
    case bfd_mach_arm_4T:
      ARMul_SelectProcessor (state, ARM_v4_Prop);
      break;

    case bfd_mach_arm_3:
    case bfd_mach_arm_3M:
      ARMul_SelectProcessor (state, ARM_Lock_Prop);
      break;

    case bfd_mach_arm_2:
    case bfd_mach_arm_2a:
      ARMul_SelectProcessor (state, ARM_Fix26_Prop);
      break;
    }

  if (   mach != bfd_mach_arm_3
      && mach != bfd_mach_arm_3M
      && mach != bfd_mach_arm_2
      && mach != bfd_mach_arm_2a)
    {
      /* Reset mode to ARM.  A gdb user may rerun a program that had entered
	 THUMB mode from the start and cause the ARM-mode startup code to be
	 executed in THUMB mode.  */
      ARMul_SetCPSR (state, SVC32MODE);
    }
  
  if (argv != NULL)
    {
      /* Set up the command line by laboriously stringing together
	 the environment carefully picked apart by our caller.  */

      /* Free any old stuff.  */
      if (state->CommandLine != NULL)
	{
	  free (state->CommandLine);
	  state->CommandLine = NULL;
	}

      /* See how much we need.  */
      for (arg = argv; *arg != NULL; arg++)
	argvlen += strlen (*arg) + 1;

      /* Allocate it.  */
      state->CommandLine = malloc (argvlen + 1);
      if (state->CommandLine != NULL)
	{
	  arg = argv;
	  state->CommandLine[0] = '\0';

	  for (arg = argv; *arg != NULL; arg++)
	    {
	      strcat (state->CommandLine, *arg);
	      strcat (state->CommandLine, " ");
	    }
	}
    }

  if (env != NULL)
    {
      /* Now see if there's a MEMSIZE spec in the environment.  */
      while (*env)
	{
	  if (strncmp (*env, "MEMSIZE=", sizeof ("MEMSIZE=") - 1) == 0)
	    {
	      char *end_of_num;

	      /* Set up memory limit.  */
	      state->MemSize =
		strtoul (*env + sizeof ("MEMSIZE=") - 1, &end_of_num, 0);
	    }
	  env++;
	}
    }

  return SIM_RC_OK;
}

void
sim_info (sd, verbose)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     int verbose ATTRIBUTE_UNUSED;
{
}

static int
frommem (state, memory)
     struct ARMul_State *state;
     unsigned char *memory;
{
  if (state->bigendSig == HIGH)
    return (memory[0] << 24) | (memory[1] << 16)
      | (memory[2] << 8) | (memory[3] << 0);
  else
    return (memory[3] << 24) | (memory[2] << 16)
      | (memory[1] << 8) | (memory[0] << 0);
}

static void
tomem (state, memory, val)
     struct ARMul_State *state;
     unsigned char *memory;
     int val;
{
  if (state->bigendSig == HIGH)
    {
      memory[0] = val >> 24;
      memory[1] = val >> 16;
      memory[2] = val >> 8;
      memory[3] = val >> 0;
    }
  else
    {
      memory[3] = val >> 24;
      memory[2] = val >> 16;
      memory[1] = val >> 8;
      memory[0] = val >> 0;
    }
}

int
sim_store_register (sd, rn, memory, length)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     int rn;
     unsigned char *memory;
     int length ATTRIBUTE_UNUSED;
{
  init ();

  if (rn == 25)
    {
      state->Cpsr = frommem (state, memory);
      ARMul_CPSRAltered (state);	     
    }
  else
    ARMul_SetReg (state, state->Mode, rn, frommem (state, memory));
  return -1;
}

int
sim_fetch_register (sd, rn, memory, length)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     int rn;
     unsigned char *memory;
     int length ATTRIBUTE_UNUSED;
{
  ARMword regval;

  init ();

  if (rn < 16)
    regval = ARMul_GetReg (state, state->Mode, rn);
  else if (rn == 25)
    /* FIXME: use PS_REGNUM from gdb/config/arm/tm-arm.h.  */
    regval = ARMul_GetCPSR (state);
  else
    /* FIXME: should report an error.  */
    regval = 0;

  while (length)
    {
      tomem (state, memory, regval);

      length -= 4;
      memory += 4;
      regval = 0;
    }  

  return -1;
}

SIM_DESC
sim_open (kind, ptr, abfd, argv)
     SIM_OPEN_KIND kind;
     host_callback *ptr;
     struct _bfd *abfd;
     char **argv;
{
  sim_kind = kind;
  if (myname) free (myname);
  myname = (char *) xstrdup (argv[0]);
  sim_callback = ptr;

  /* Decide upon the endian-ness of the processor.
     If we can, get the information from the bfd itself.
     Otherwise look to see if we have been given a command
     line switch that tells us.  Otherwise default to little endian.  */
  if (abfd != NULL)
    big_endian = bfd_big_endian (abfd);
  else if (argv[1] != NULL)
    {
      int i;

      /* Scan for endian-ness switch.  */
      for (i = 0; (argv[i] != NULL) && (argv[i][0] != 0); i++)
	if (argv[i][0] == '-' && argv[i][1] == 'E')
	  {
	    char c;

	    if ((c = argv[i][2]) == 0)
	      {
		++i;
		c = argv[i][0];
	      }

	    switch (c)
	      {
	      case 0:
		sim_callback->printf_filtered
		  (sim_callback, "No argument to -E option provided\n");
		break;

	      case 'b':
	      case 'B':
		big_endian = 1;
		break;

	      case 'l':
	      case 'L':
		big_endian = 0;
		break;

	      default:
		sim_callback->printf_filtered
		  (sim_callback, "Unrecognised argument to -E option\n");
		break;
	      }
	  }
    }

  return (SIM_DESC) 1;
}

void
sim_close (sd, quitting)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     int quitting ATTRIBUTE_UNUSED;
{
  if (myname)
    free (myname);
  myname = NULL;
}

SIM_RC
sim_load (sd, prog, abfd, from_tty)
     SIM_DESC sd;
     char *prog;
     bfd *abfd;
     int from_tty ATTRIBUTE_UNUSED;
{
  bfd *prog_bfd;

  prog_bfd = sim_load_file (sd, myname, sim_callback, prog, abfd,
			    sim_kind == SIM_OPEN_DEBUG, 0, sim_write);
  if (prog_bfd == NULL)
    return SIM_RC_FAIL;
  ARMul_SetPC (state, bfd_get_start_address (prog_bfd));
  if (abfd == NULL)
    bfd_close (prog_bfd);
  return SIM_RC_OK;
}

void
sim_stop_reason (sd, reason, sigrc)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     enum sim_stop *reason;
     int *sigrc;
{
  if (stop_simulator)
    {
      *reason = sim_stopped;
      *sigrc = SIGINT;
    }
  else if (state->EndCondition == 0)
    {
      *reason = sim_exited;
      *sigrc = state->Reg[0] & 255;
    }
  else
    {
      *reason = sim_stopped;
      if (state->EndCondition == RDIError_BreakpointReached)
	*sigrc = SIGTRAP;
      else
	*sigrc = 0;
    }
}

void
sim_do_command (sd, cmd)
     SIM_DESC sd ATTRIBUTE_UNUSED;
     char *cmd ATTRIBUTE_UNUSED;
{  
  (*sim_callback->printf_filtered)
    (sim_callback,
     "This simulator does not accept any commands.\n");
}

void
sim_set_callbacks (ptr)
     host_callback *ptr;
{
  sim_callback = ptr;
}