/*
 *  This file contains the MVME162 console IO package.
 *
 *  COPYRIGHT (c) 1989-1997.
 *  On-Line Applications Research Corporation (OAR).
 *  Copyright assigned to U.S. Government, 1994.
 *
 *  The license and distribution terms for this file may in
 *  the file LICENSE in this distribution or at
 *  http://www.OARcorp.com/rtems/license.html.
 *
 *  Modifications of respective RTEMS file: COPYRIGHT (c) 1994.
 *  EISCAT Scientific Association. M.Savitski
 *
 *  This material is a part of the MVME162 Board Support Package
 *  for the RTEMS executive. Its licensing policies are those of the
 *  RTEMS above.
 *
 *  $Id$
 */

#define M162_INIT

#include <bsp.h>
#include <rtems/libio.h>
#include <ringbuf.h>

Ring_buffer_t  Buffer[2];

/*
 *  Interrupt handler for receiver interrupts
 */

rtems_isr C_Receive_ISR(rtems_vector_number vector)
{
  register int    ipend, port;

  ZWRITE0(1, 0x38);     /* reset highest IUS */

  ipend = ZREAD(1, 3);  /* read int pending from A side */

  if      (ipend == 0x04) port = 0;   /* channel B intr pending */
  else if (ipend == 0x20) port = 1;   /* channel A intr pending */
  else return;
    
  Ring_buffer_Add_character(&Buffer[port], ZREADD(port));
  
  if (ZREAD(port, 1) & 0x70) {    /* check error stat */
    ZWRITE0(port, 0x30);          /* reset error */
  }
}

rtems_device_driver console_initialize(
  rtems_device_major_number  major,
  rtems_device_minor_number  minor,
  void                      *arg
)
{
  int     i;
  rtems_status_code status;
  
  /*
   * Initialise receiver interrupts on both ports
   */

  for (i = 0; i <= 1; i++) {
    Ring_buffer_Initialize( &Buffer[i] );
    ZWRITE(i, 2, SCC_VECTOR);
    ZWRITE(i, 10, 0);
    ZWRITE(i, 1, 0x10);     /* int on all Rx chars or special condition */
    ZWRITE(i, 9, 8);        /* master interrupt enable */
  }
    
  set_vector(C_Receive_ISR, SCC_VECTOR, 1); /* install ISR for ports A and B */

  mcchip->vector_base = 0;
  mcchip->gen_control = 2;        /* MIEN */
  mcchip->SCC_int_ctl = 0x13;     /* SCC IEN, IPL3 */

  status = rtems_io_register_name(
    "/dev/console",
    major,
    (rtems_device_minor_number) 1
  );
 
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred(status);
 
  status = rtems_io_register_name(
    "/dev/tty00",
    major,
    (rtems_device_minor_number) 0
  );
 
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred(status);
 
  status = rtems_io_register_name(
    "/dev/tty01",
    major,
    (rtems_device_minor_number) 1
  );
 
  if (status != RTEMS_SUCCESSFUL)
    rtems_fatal_error_occurred(status);
 
  return RTEMS_SUCCESSFUL;
}

/*
 *   Non-blocking char input
 */

rtems_boolean char_ready(int port, char *ch)
{
  if ( Ring_buffer_Is_empty( &Buffer[port] ) )
    return FALSE;

  Ring_buffer_Remove_character( &Buffer[port], *ch );
  
  return TRUE;
}

/*
 *   Block on char input
 */

char inbyte(int port)
{
  unsigned char tmp_char;
 
  while ( !char_ready(port, &tmp_char) );
  return tmp_char;
}

/*  
 *   This routine transmits a character out the SCC.  It no longer supports
 *   XON/XOFF flow control.
 */

void outbyte(char ch, int port)
{
  while (1) {
    if (ZREAD0(port) & TX_BUFFER_EMPTY) break;
  }
  ZWRITED(port, ch);
}

/*
 *  Open entry point
 */

rtems_device_driver console_open(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  return RTEMS_SUCCESSFUL;
}
 
/*
 *  Close entry point
 */

rtems_device_driver console_close(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  return RTEMS_SUCCESSFUL;
}

/*
 * read bytes from the serial port. We only have stdin.
 */

rtems_device_driver console_read(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  rtems_libio_rw_args_t *rw_args;
  char *buffer;
  int maximum;
  int count = 0;
 
  rw_args = (rtems_libio_rw_args_t *) arg;

  buffer = rw_args->buffer;
  maximum = rw_args->count;

  if ( minor > 1 )
    return RTEMS_INVALID_NUMBER;

  for (count = 0; count < maximum; count++) {
    buffer[ count ] = inbyte( minor );
    if (buffer[ count ] == '\n' || buffer[ count ] == '\r') {
      buffer[ count++ ]  = '\n';
      buffer[ count ]  = 0;
      break;
    }
  }

  rw_args->bytes_moved = count;
  return (count >= 0) ? RTEMS_SUCCESSFUL : RTEMS_UNSATISFIED;
}

/*
 * write bytes to the serial port. Stdout and stderr are the same. 
 */

rtems_device_driver console_write(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  int count;
  int maximum;
  rtems_libio_rw_args_t *rw_args;
  char *buffer;

  rw_args = (rtems_libio_rw_args_t *) arg;

  buffer = rw_args->buffer;
  maximum = rw_args->count;

  if ( minor > 1 )
    return RTEMS_INVALID_NUMBER;

  for (count = 0; count < maximum; count++) {
    if ( buffer[ count ] == '\n') {
      outbyte('\r', minor );
    }
    outbyte( buffer[ count ], minor  );
  }

  rw_args->bytes_moved = maximum;
  return 0;
}

/*
 *  IO Control entry point
 */

rtems_device_driver console_control(
  rtems_device_major_number major,
  rtems_device_minor_number minor,
  void                    * arg
)
{
  return RTEMS_SUCCESSFUL;
}