remote-es1800.c

早期freebsd实现

   MEMADDR is the address in the remote memory space.
   MYADDR is the address of the buffer in our space.
   LEN is the number of bytes.
 
   memaddr - the target's address
   myaddr  - gdb's address
   len     - number of bytes   */

static void
es1800_write_bytes (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
{
  char buf[PBUFSIZ];
  int i;
  char *p;

  p = myaddr;
  for (i = 0; i < len; i++)
    {
      sprintf (buf, "@.B$%x=$%x", memaddr+i, (*p++) & 0xff);
      send_with_reply (buf, buf, sizeof (buf));      /* FIXME send_command? */
    }
}


/* Read memory data directly from the emulator.
   This does not use the data cache; the data cache uses this.
 
   memaddr - the target's address
   myaddr  - gdb's address
   len     - number of bytes   */

static void
es1800_read_bytes (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
{
  static int DB_tab[16] = {8,11,14,17,20,23,26,29,34,37,40,43,46,49,52,55};
  char buf[PBUFSIZ];
  int i;
  int low_addr;
  char *p;
  char *b;

  if (len > PBUFSIZ / 2 - 1)
    {
      abort ();
    }

  if (len == 1)	/* The emulator does not like expressions like:  */
    {
      len = 2;	/* DB.B $20018 TO $20018                       */
    }

  /* Reply describes registers byte by byte, each byte encoded as two hex
     characters.  */

  sprintf (buf, "DB.B $%x TO $%x", memaddr, memaddr+len-1);
  send_with_reply (buf, buf, sizeof (buf));
  b = buf;
  low_addr = memaddr&0x0f;
  for (i = low_addr; i < low_addr + len; i++)
    {
      if ((!(i % 16)) && i)
	{   /* if (i = 16,32,48)  */
	  while (*p++!='\n') {;}
	  b = p;
	}
      p = b + DB_tab[i%16] + (m68020 ? 2 : 0);
      if (p[0] == 32 || p[1] == 32)
	{
	  error ("Emulator reply is too short: %s", buf);
	}
      myaddr[i-low_addr] = fromhex (p[0]) * 16 + fromhex (p[1]);
    }
}

/* Information about the current target  */

static void
es1800_files_info (tops)
     struct target_ops *tops;	/* Unused */
{
  printf ("ES1800 Attached to %s at %d baud in %s mode\n", savename, 19200,
	  MODE);
}


/* We read the contents of the target location and stash it,
   then overwrite it with a breakpoint instruction.
 
   addr           - is the target location in the target machine.
   contents_cache - is a pointer to memory allocated for saving the target contents.
                    It is guaranteed by the caller to be long enough to save sizeof 
                    BREAKPOINT bytes.
 
   FIXME: This size is target_arch dependent and should be available in
   the target_arch transfer vector, if we ever have one...  */

static int
es1800_insert_breakpoint (addr, contents_cache)
     CORE_ADDR addr;
     char *contents_cache;
{
  int val; 

  val = target_read_memory (addr, contents_cache, sizeof (es1800_break_insn));

  if (val == 0)
    {
      val = target_write_memory (addr, es1800_break_insn,
				 sizeof (es1800_break_insn));
    }

  return (val);
}


/* Write back the stashed instruction
 
   addr           - is the target location in the target machine.
   contents_cache - is a pointer to memory allocated for saving the target contents.
                    It is guaranteed by the caller to be long enough to save sizeof 
                    BREAKPOINT bytes.	*/
 
static int
es1800_remove_breakpoint (addr, contents_cache)
     CORE_ADDR addr;
     char *contents_cache;
{

  return (target_write_memory (addr, contents_cache,
			       sizeof (es1800_break_insn)));
}

/* create_break_insn ()
   Primitive datastructures containing the es1800 breakpoint instruction  */

static void
es1800_create_break_insn (ins, vec)
     char *ins;
     int vec;
{
  if (vec == 15)
    {
      ins[0] = 0x4e;
      ins[1] = 0x4f;
    }
}


/* verify_break ()
   Seach for breakpoint routine in emulator memory.
   returns non-zero on failure
   vec - trap vector used for breakpoints  */

static int
verify_break (vec)
     int vec;
{
  CORE_ADDR memaddress;
  char buf[8];
  char *instr = "NqNqNqNs";      /* breakpoint routine */
  int status;

  get_break_addr (vec, &memaddress);

  if (memaddress)
    {
      status = target_read_memory (memaddress, buf, 8); 
      if (status != 0)
	{
	  memory_error (status, memaddress);
	}
      return (strcmp (instr, buf));
    }
    return (-1);
}


/* get_break_addr ()
   find address of breakpint routine
   vec - trap vector used for breakpoints
   addrp - store the address here	*/

static void
get_break_addr (vec, addrp)
     int vec;
     CORE_ADDR *addrp;
{
  CORE_ADDR memaddress = 0;
  int status;
  int k;
  char buf[PBUFSIZ];
  char base_addr[4];
  char *p;

  if (m68020)
    {
      send_with_reply ("VBR ", buf, sizeof (buf));
      p = buf;
      for (k = 0; k < 4; k++)
	{
	  if ((p[k*2 + 1] == 0) || (p[k*2 + 2] == 0))
	    {
	      error ("Emulator reply is too short: %s", buf);
	    }
	  base_addr[k] = (fromhex (p[k*2 + 1]) * 16) + fromhex (p[k*2 + 2]);
	}
      /* base addr of exception vector table */
      memaddress = *((CORE_ADDR *) base_addr);
    }

    memaddress += (vec + 32) * 4;     /* address of trap vector */
    status = target_read_memory (memaddress, (char *) addrp, 4); 
    if (status != 0)                                                   
      {
	memory_error (status, memaddress);
      }
}


/* Kill an inferior process */

static void
es1800_kill ()
{
  if (inferior_pid != 0)
    {
      inferior_pid = 0;
      es1800_mourn_inferior ();
    }
}


/* Load a file to the ES1800 emulator. 
   Converts the file from a.out format into Extended Tekhex format
   before the file is loaded.
   Also loads the trap routine, and sets the ES1800 breakpoint on it
   filename - the a.out to be loaded
   from_tty - says whether to be verbose or not
   FIXME Uses emulator overlay memory for trap routine	*/
 
static void
es1800_load (filename, from_tty)
     char *filename;
     int from_tty;
{

  FILE *instream;
  char loadname[15];
  char buf[160];
  struct cleanup *old_chain;
  int es1800_load_format = 5;

  if (es1800_desc < 0) 
    {
      printf ("No emulator attached, type emulator-command first\n");
      return;
    }

  filename = tilde_expand (filename);
  make_cleanup (free, filename);

  switch (es1800_load_format)
    {
      case 2:   /* Extended Tekhex  */
        if (from_tty)
	  {
	    printf ("Converting \"%s\" to Extended Tekhex Format\n", filename);
	  }
	sprintf (buf, "tekhex %s", filename);
	system (buf);
	sprintf (loadname, "out.hex");
	break;

      case 5:   /* Motorola S-rec  */
	if (from_tty)
	  {
	    printf ("Converting \"%s\" to Motorola S-record format\n",
		    filename);
	  }
	/* in the future the source code in copy (part of binutils-1.93) will
	   be included in this file */
	sprintf (buf,
		 "copy -s \"a.out-sunos-big\" -d \"srec\" %s /tmp/out.hex",
		 filename);
	system (buf);
	sprintf (loadname, "/tmp/out.hex");
	break;

      default:
	error ("Downloading format not defined\n");
    }
 
  mark_breakpoints_out ();
  inferior_pid = 0;
  if (from_tty)
    {
      printf ("Downloading \"%s\" to the ES 1800\n",filename);
    }
  if ((instream = fopen (loadname, "r")) == NULL)
    {
      perror_with_name ("fopen:");
    }

  old_chain = make_cleanup (fclose, instream);
  immediate_quit++;

  es1800_reset (0);

  download (instream, from_tty, es1800_load_format);

  /* if breakpoint routine is not present anymore we have to check 
     whether to download a new breakpoint routine or not */

  if ((verify_break (es1800_break_vec) != 0)
      && query ("No breakpoint routine in ES 1800 emulator!\nDownload a breakpoint routine to the emulator? "))
    {
      char buf[128];
      printf ("Using break vector 0x%x\n", es1800_break_vec);
      sprintf (buf, "0x%x ", es1800_break_vec);
      printf ("Give the start address of the breakpoint routine: ");
      fgets (buf + strlen (buf), sizeof (buf) - strlen (buf), stdin);
      es1800_init_break (buf, 0);
    }

  do_cleanups (old_chain);
  expect_prompt ();
  readchar ();  /* FIXME I am getting a ^G = 7 after the prompt  */
  printf ("\n");

  if (fclose (instream) == EOF)
    {
      ;
    }

  if (es1800_load_format != 2)
    {
      sprintf (buf, "/usr/bin/rm %s", loadname);
      system (buf);
    }

  symbol_file_command (filename, from_tty);   /* reading symbol table */
  immediate_quit--;
}

#if 0

#define NUMCPYBYTES 20

static void
bfd_copy (from_bfd, to_bfd)
     bfd *from_bfd;
     bfd *to_bfd;
{
  asection *p, *new;
  int i;
  char buf[NUMCPYBYTES];

  for (p = from_bfd->sections; p != NULL; p = p->next)
    {
      printf ("  Copying section %s. Size = %x.\n", p->name, p->_cooked_size);
      printf ("    vma = %x,  offset = %x,  output_sec = %x\n",
	      p->vma, p->output_offset, p->output_section);
      new = bfd_make_section (to_bfd, p->name);
      if (p->_cooked_size &&
	  !bfd_set_section_size (to_bfd, new, p->_cooked_size))
	{
	  error ("Wrong BFD size!\n");
	}
      if (!bfd_set_section_flags (to_bfd, new, p->flags))
	{
	  error ("bfd_set_section_flags");
	}
      new->vma = p->vma;
      
      for (i = 0; (i + NUMCPYBYTES) < p->_cooked_size ; i += NUMCPYBYTES)
	{
	  if (!bfd_get_section_contents (from_bfd, p, (PTR) buf, (file_ptr) i,
					(bfd_size_type) NUMCPYBYTES))
	    {
	      error ("bfd_get_section_contents\n");
	    }
	if (!bfd_set_section_contents (to_bfd, new, (PTR) buf, (file_ptr) i,
				      (bfd_size_type) NUMCPYBYTES))
	  {
	    error ("bfd_set_section_contents\n");
	  }
      }
      bfd_get_section_contents (from_bfd, p, (PTR) buf, (file_ptr) i,
				(bfd_size_type) (p->_cooked_size - i));
      bfd_set_section_contents (to_bfd, new, (PTR) buf,(file_ptr) i,
				(bfd_size_type) (p->_cooked_size - i));
    }
}

#endif

/* Start an process on the es1800 and set inferior_pid to the new
   process' pid.
   execfile - the file to run
   args     - arguments passed to the program
   env      - the environment vector to pass	*/

static void
es1800_create_inferior (execfile, args, env)
     char *execfile;
     char *args;
     char **env;
{
  int entry_pt;
  int pid;
#if 0
  struct expression *expr;
  register struct cleanup *old_chain = 0;
  register value val;
#endif

  if (args && *args)
    {
      error ("Can't pass arguments to remote ES1800 process");
    }

#if 0
  if (query ("Use 'start' as entry point? "))
    {
      expr = parse_c_expression ("start");
      old_chain = make_cleanup (free_current_contents, &expr);
      val = evaluate_expression (expr);
      entry_pt = (val->location).address;
    }
  else
    {
      printf ("Enter the program's entry point (in hexadecimal): ");
      scanf ("%x", &entry_pt);
    }
#endif

  if (execfile == 0 || exec_bfd == 0)
    {
      error ("No exec file specified");
    }

  entry_pt = (int) bfd_get_start_address (exec_bfd);

  pid = 42;

  /* Now that we have a child process, make it our target.  */

  push_target (&es1800_child_ops);

  /* The "process" (board) is already stopped awaiting our commands, and
     the program is already downloaded.  We just set its PC and go.  */

  inferior_pid = pid;		/* Needed for wait_for_inferior below */

  clear_proceed_status ();

  /* Tell wait_for_inferior that we've started a new process.  */

  init_wait_for_inferior ();

  /* Set up the "saved terminal modes" of the inferior
     based on what modes we are starting it with.  */

  target_terminal_init ();

  /* Install inferior's terminal modes.  */

  target_terminal_inferior ();

  /* remote_start (args); */
  /* trap_expected = 0; */
  /* insert_step_breakpoint ();  FIXME, do we need this?  */

  proceed ((CORE_ADDR) entry_pt, -1, 0);		/* Let 'er rip... */

}


/* The process has died, clean up.  */

static void
es1800_mourn_inferior ()
{
  remove_breakpoints ();
  unpush_target (&es1800_child_ops);
  generic_mourn_inferior ();	/* Do all the proper things now */
}

/* ES1800-protocol specific routines */

/* Keep discarding input from the remote system, until STRING is found. 
   Let the user break out immediately. 
   string - the string to expect
   nowait - break out if string not the emulator's first respond otherwise
            read until string is found (== 0)   */
 
static void
expect (string, nowait)
     char *string;
    int nowait;
{
  char c;
  char *p = string;

  immediate_quit++;
  while (1)
    {
      c = readchar ();
      if (isalpha (c))
	{
	  c = toupper (c);
	}
      if (c == toupper (*p))
	{
	  p++;
	  if (*p == '\0')
	    {
	      immediate_quit--;
	      return;
	    }
	}
      else if (!nowait)
	{
	  p = string;
	}
      else
	{
	  printf ("\'%s\' expected\n" , string);
	  printf ("char %d is %d", p - string, c);
	  error ("\n" );
	}
    }
}

/* Keep discarding input until we see the prompt.  */

static void
expect_prompt ()
{
  expect (">", 0);
}


/* Read one character */

#ifdef DEBUG_STDIN

/* read from stdin */

static int
readchar ()
{
  char buf[1];

  buf[0] = '\0';
  printf ("readchar, give one character\n");
  read (0, buf, 1);

#if defined (LOG_FILE)
  putc (buf[0] & 0x7f, log_file);