console.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

  /* 
   *  Redirection of .INSTAT does not work: 167-Bug crashes.
   *  Switch the input stream to the specified port.
   *  Make sure this is atomic code.
   */
  rtems_interrupt_disable( previous_level );
  
  asm volatile( "movew  %1, -(%%sp)\n\t"/* Channel */
                "trap   #15\n\t"        /* Trap to 167Bug */
                ".short 0x61\n\t"       /* Code for .REDIR_I */
                "trap   #15\n\t"        /* Trap to 167Bug */
		".short 0x01\n\t"       /* Code for .INSTAT */
                "move   %%cc, %0\n\t"   /* Get condition codes */
                "andil  #4, %0"         /* Keep the Zero bit */
    : "=d" (char_not_available) : "d" (minor): "%%cc" );

  if (char_not_available) {
    rtems_interrupt_enable( previous_level );
    return -1;
  }

  /* Read the char and return it */
  asm volatile( "subq.l #2,%%a7\n\t"    /* Space for result */
                "trap   #15\n\t"        /* Trap to 167 Bug */
                ".short 0x00\n\t"       /* Code for .INCHR */
                "moveb  (%%a7)+, %0"    /* Pop char into c */
    : "=d" (c) : );

  rtems_interrupt_enable( previous_level );
  
  return (int)c;
}


/*
 * _167Bug_pollWrite
 *
 *  Output buffer through 167Bug. Returns only once every character has been
 *  sent (polled output).
 *
 *  Input parameters:
 *    minor - selected channel
 *    buf - output buffer
 *    len - number of chars to output
 *
 *  Output parameters:  NONE
 *
 *  Return value: IGNORED
 *
 *  CANNOT BE COMBINED WITH INTERRUPT DRIVEN I/O!
 */
int _167Bug_pollWrite(
  int minor,
  const char *buf,
  int len
)
{
  const char *endbuf = buf + len;

  asm volatile( "pea    (%0)\n\t"            /* endbuf */
                "pea    (%1)\n\t"            /* buf */
                "movew  #0x21, -(%%sp)\n\t"  /* Code for .OUTSTR */
                "movew  %2, -(%%sp)\n\t"     /* Channel */
                "trap   #15\n\t"             /* Trap to 167Bug */
                ".short 0x60"                /* Code for .REDIR */
    :: "a" (endbuf), "a" (buf), "d" (minor) );

  /* Return something */
  return RTEMS_SUCCESSFUL;
}


/*
 *  do_poll_read
 *
 *  Input characters through 167Bug. Returns has soon as a character has been
 *  received. Otherwise, if we wait for the number of requested characters, we
 *  could be here forever!
 *
 *  CR is converted to LF on input. The terminal should not send a CR/LF pair
 *  when the return or enter key is pressed.
 *
 *  Input parameters:
 *    major - ignored. Should be the major number for this driver.
 *    minor - selected channel.
 *    arg->buffer - where to put the received characters.
 *    arg->count  - number of characters to receive before returning--Ignored.
 *
 *  Output parameters:
 *    arg->bytes_moved - the number of characters read. Always 1.
 *
 *  Return value: RTEMS_SUCCESSFUL
 *
 *  CANNOT BE COMBINED WITH INTERRUPT DRIVEN I/O!
 */
rtems_status_code do_poll_read(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  rtems_libio_rw_args_t *rw_args = arg;
  int c;

  while( (c = _167Bug_pollRead (minor)) == -1 );
  rw_args->buffer[0] = (unsigned8)c;
  if( rw_args->buffer[0] == '\r' )
      rw_args->buffer[0] = '\n';
  rw_args->bytes_moved = 1;
  return RTEMS_SUCCESSFUL;
}

/*
 *  do_poll_write
 *
 *  Output characters through 167Bug. Returns only once every character has
 *  been sent.
 *
 *  CR is transmitted AFTER a LF on output. 
 *
 *  Input parameters:
 *    major - ignored. Should be the major number for this driver.
 *    minor - selected channel
 *    arg->buffer - where to get the characters to transmit.
 *    arg->count  - the number of characters to transmit before returning.
 *
 *  Output parameters:
 *    arg->bytes_moved - the number of characters read
 *
 *  Return value: RTEMS_SUCCESSFUL
 *
 *  CANNOT BE COMBINED WITH INTERRUPT DRIVEN I/O!
 */
rtems_status_code do_poll_write(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  rtems_libio_rw_args_t *rw_args = arg;
  unsigned32 i;
  char cr ='\r';

  for( i = 0; i < rw_args->count; i++ ) {
    _167Bug_pollWrite(minor, &(rw_args->buffer[i]), 1);
    if ( rw_args->buffer[i] == '\n' )
      _167Bug_pollWrite(minor, &cr, 1);
  }
  rw_args->bytes_moved = i;
  return RTEMS_SUCCESSFUL;
}


/*
 *  _BSP_output_char
 *
 *  printk() function prototyped in bspIo.h. Does not use termios.
 */
void _BSP_output_char(char c)
{
  rtems_device_minor_number printk_minor;
  char cr ='\r';
  
  /* 
   *  Can't rely on console_initialize having been called before this function
   *  is used.
   */
  if ( NVRAM_CONFIGURE )
    /* J1-4 is on, use NVRAM info for configuration */
    printk_minor = (nvram->console_printk_port & 0x30) >> 4;
  else
    printk_minor = PRINTK_MINOR;
   
  _167Bug_pollWrite(printk_minor, &c, 1);
  if ( c == '\n' )
      _167Bug_pollWrite(printk_minor, &cr, 1);
}

  
/*
 ***************
 * BOILERPLATE *
 ***************
 *
 *  All these functions are prototyped in rtems/c/src/lib/include/console.h.
 */

/*
 * Initialize and register the device
 */
rtems_device_driver console_initialize(
  rtems_device_major_number  major,
  rtems_device_minor_number  minor,
  void                      *arg
)
{
  rtems_status_code status;
  rtems_device_minor_number console_minor;

  /*
   * Set up TERMIOS if needed
   */
  if ( NVRAM_CONFIGURE ) {
    /* J1-4 is on, use NVRAM info for configuration */
    console_minor = nvram->console_printk_port & 0x03;
          
    if ( nvram->console_mode & 0x01 )
      /* termios */
      rtems_termios_initialize ();
  }
  else {
    console_minor = CONSOLE_MINOR;
#if CD2401_USE_TERMIOS == 1
    rtems_termios_initialize ();
#endif
  }

  /*
   * Do device-specific initialization
   * Does not affect 167-Bug.
   */
  cd2401_initialize ();

  /*
   * Register the devices
   */
  status = rtems_io_register_name ("/dev/tty0", major, 0);
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred (status);

  status = rtems_io_register_name ("/dev/tty1", major, 1);
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred (status);

  status = rtems_io_register_name ("/dev/console", major, console_minor);
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred (status);

  status = rtems_io_register_name ("/dev/tty2", major, 2);
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred (status);

  status = rtems_io_register_name ("/dev/tty3", major, 3);
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred (status);

  return RTEMS_SUCCESSFUL;
}

/*
 * Open the device
 */
rtems_device_driver console_open(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  static const rtems_termios_callbacks pollCallbacks = {
    NULL,                       /* firstOpen */
    NULL,                       /* lastClose */
    _167Bug_pollRead,           /* pollRead */
    _167Bug_pollWrite,          /* write */
    NULL,                       /* setAttributes */
    NULL,                       /* stopRemoteTx */
    NULL,                       /* startRemoteTx */
    0                           /* outputUsesInterrupts */
  };
  
  static const rtems_termios_callbacks intrCallbacks = {
    cd2401_firstOpen,           /* firstOpen */
    cd2401_lastClose,           /* lastClose */
    NULL,                       /* pollRead */
    cd2401_write,               /* write */
    cd2401_setAttributes,       /* setAttributes */
    cd2401_stopRemoteTx,        /* stopRemoteTx */
    cd2401_startRemoteTx,       /* startRemoteTx */
    1                           /* outputUsesInterrupts */
  };

  if ( NVRAM_CONFIGURE )
    /* J1-4 is on, use NVRAM info for configuration */ 
    if ( nvram->console_mode & 0x01 )
      /* termios */
      if ( nvram->console_mode & 0x02 )
        /* interrupt-driven I/O */
        return rtems_termios_open (major, minor, arg, &intrCallbacks);
	    else
        /* polled I/O */
        return rtems_termios_open (major, minor, arg, &pollCallbacks);
	  else
	    /* no termios -- default to polled I/O */
	    return RTEMS_SUCCESSFUL;
#if CD2401_USE_TERMIOS == 1
#if CD2401_IO_MODE != 1
  else
    /* termios & polled I/O*/
    return rtems_termios_open (major, minor, arg, &pollCallbacks);
#else
  else
    /* termios & interrupt-driven I/O*/
    return rtems_termios_open (major, minor, arg, &intrCallbacks);
#endif
#else
  else
    /* no termios -- default to polled I/O */
    return RTEMS_SUCCESSFUL;
#endif
}


/*
 * Close the device
 */
rtems_device_driver console_close(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  if ( NVRAM_CONFIGURE ) {
    /* J1-4 is on, use NVRAM info for configuration */ 
    if ( nvram->console_mode & 0x01 )
      /* termios */
      return rtems_termios_close (arg);
    else
      /* no termios */
      return RTEMS_SUCCESSFUL;
  }
#if CD2401_USE_TERMIOS == 1
  else
    /* termios */
    return rtems_termios_close (arg);
#else
  else
    /* no termios */
    return RTEMS_SUCCESSFUL;
#endif
}


/*
 * Read from the device
 */
rtems_device_driver console_read(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  if ( NVRAM_CONFIGURE ) {
    /* J1-4 is on, use NVRAM info for configuration */ 
    if ( nvram->console_mode & 0x01 )
      /* termios */
      return rtems_termios_read (arg);
    else
      /* no termios -- default to polled */
      return do_poll_read (major, minor, arg);
  }
#if CD2401_USE_TERMIOS == 1
  else
    /* termios */
    return rtems_termios_read (arg);
#else
  else
    /* no termios -- default to polled */
    return do_poll_read (major, minor, arg);
#endif
}


/*
 * Write to the device
 */
rtems_device_driver console_write(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  if ( NVRAM_CONFIGURE ) {
    /* J1-4 is on, use NVRAM info for configuration */ 
    if ( nvram->console_mode & 0x01 )
      /* termios */
      return rtems_termios_write (arg);
    else
      /* no termios -- default to polled */
      return do_poll_write (major, minor, arg);
  }
#if CD2401_USE_TERMIOS == 1
  else
    /* termios */
    return rtems_termios_write (arg);
#else
  else
    /* no termios -- default to polled */
    return do_poll_write (major, minor, arg);
#endif
}


/*
 * Handle ioctl request.
 */
rtems_device_driver console_control(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  if ( NVRAM_CONFIGURE ) {
    /* J1-4 is on, use NVRAM info for configuration */ 
    if ( nvram->console_mode & 0x01 )
      /* termios */
      return rtems_termios_ioctl (arg);
    else
      /* no termios -- default to polled */
      return RTEMS_SUCCESSFUL;
  }
#if CD2401_USE_TERMIOS == 1
  else
    /* termios */
    return rtems_termios_ioctl (arg);
#else
  else
    /* no termios -- default to polled */
    return RTEMS_SUCCESSFUL;
#endif
}