console.c

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

/*
 *  console.c
 *
 *  This file contains the MBX8xx termios serial I/O package.
 *  Only asynchronous I/O is supported.
 *
 *  The SCCs and SMCs are assigned as follows
 *
 *   Channel     Device      Minor   Note
 *    SMC1      /dev/tty0      0
 *    SMC2      /dev/tty1      1
 *    SCC1                     2     N/A. Hardwired as ethernet port
 *    SCC2      /dev/tty2      3
 *    SCC3      /dev/tty3      4
 *    SCC4      /dev/tty4      5
 *
 *  All ports support termios. The use of termios is recommended for real-time
 *  applications. Termios provides buffering and input processing. When not
 *  using termios, processing is limited to the substitution of LF for CR on
 *  input, and the output of a CR following the output of a LF character.
 *  Note that the terminal should not send CR/LF pairs when the return key
 *  is pressed, and that output lines are terminated with LF/CR, not CR/LF
 *  (although that would be easy to change).
 *
 *  I/O may be interrupt-driven (recommended for real-time applications) or
 *  polled. Polled I/O may be performed by this device driver entirely, or
 *  in part by EPPCBug. With EPPCBug 1.1, polled I/O is limited to the
 *  EPPCBug debug console. This is a limitation of the firmware. Later
 *  firmware may be able to do I/O through any port. This code assumes
 *  that the EPPCBug console is the default: SMC1. If the console and
 *  printk ports are set to anything else with EPPCBug polled I/O, the
 *  system will hang. Only port SMC1 is usable with EPPCBug polled I/O.
 *
 *  LIMITATIONS:
 *
 *  It is not possible to use different I/O modes on the different ports. The
 *  exception is with printk. The printk port can use a different mode from
 *  the other ports. If this is done, it is important not to open the printk
 *  port from an RTEMS application.
 *
 *  Currently, the I/O modes are determined at build time. It would be much
 *  better to have the mode selected at boot time based on parameters in
 *  NVRAM.
 *
 *  Interrupt-driven I/O requires termios.
 *
 *  TESTS:
 * 
 *  TO RUN THE TESTS, USE POLLED I/O WITHOUT TERMIOS SUPPORT. Some tests
 *  play with the interrupt masks and turn off I/O. Those tests will hang
 *  when interrupt-driven I/O is used. Other tests, such as cdtest, do I/O
 *  from the static constructors before the console is open. This test
 *  will not work with interrupt-driven I/O. Because of the buffering
 *  performed in termios, test output may not be in sequence.The tests
 *  should all be fixed to work with interrupt-driven I/O and to
 *  produce output in the expected sequence. Obviously, the termios test
 *  requires termios support in the driver.
 *  
 *  Set CONSOLE_MINOR to the appropriate device minor number in the
 *  config file. This allows the RTEMS application console to be different
 *  from the EPPBug debug console or the GDB port.
 * 
 *  This driver handles all five available serial ports: it distinguishes
 *  the sub-devices using minor device numbers. It is not possible to have
 *  other protocols running on the other ports when this driver is used as
 *  currently written.
 *  
 *  Based on code (alloc860.c in eth_comm port) by
 *  Jay Monkman ([e-mail]),
 *  Copyright (C) 1998 by Frasca International, Inc.
 *
 *  Modifications by Darlene Stewart <[e-mail]>
 *  and Charles-Antoine Gauthier <[e-mail]>.
 *  Copyright (c) 2000, National Research Council of Canada
 *
 */
#include <stdarg.h>
#include <stdio.h>
#include <bsp.h>                /* Must be before libio.h */
#include <rtems/bspIo.h>
#include <rtems/libio.h>
#include <termios.h>
#include <bsp/mbx.h>

static int _EPPCBug_pollRead( int minor );
static int _EPPCBug_pollWrite( int minor, const char *buf, int len );
static void _BSP_output_char( char c );
static rtems_status_code do_poll_read( rtems_device_major_number major, rtems_device_minor_number minor, void * arg);
static rtems_status_code do_poll_write( rtems_device_major_number major, rtems_device_minor_number minor, void * arg);

static void _BSP_null_char( char c ) {return;}
static void serial_putchar(const char c);

BSP_output_char_function_type BSP_output_char = _BSP_null_char;


/*
 * _EPPCBug_pollRead
 *
 *  Read a character from the EPPCBug console, and return it. Return -1
 *  if there is no character in the input FIFO.
 *
 *  Input parameters:
 *    minor - selected channel
 *
 *  Output parameters:  NONE
 *
 *  Return value: char returned as positive signed int
 *                -1 if no character is present in the input FIFO.
 */
static int _EPPCBug_pollRead(
  int minor
)
{
  extern volatile m8xx_t m8xx;

  char c;
  volatile int simask;		/* We must read and write m8xx.simask */
  int retval;
  ISR_Level level;
  
  struct {
    int clun;
    int dlun;
    char * inbuf;
    int nbytes_requested;
    int reserved;
  } volatile input_params;
  
  struct {
    int status;
    union {
      struct {
        int input_char_available;
        int output_possible;
        int break_detected;
        int modem_status;
      } stat;
      struct {
        int nbytes_received;
      } read;
    } u;
  } volatile output_params;

  retval = -1;

  input_params.clun = 0;
  
  switch( minor ) {
    case SMC1_MINOR:    
      input_params.dlun = 0;  /* Should be 4, but doesn't work with EPPCBug 1.1 */
      break;
    case SMC2_MINOR:    
      input_params.dlun = 5;
      break;
    case SCC2_MINOR:    
      input_params.dlun = 1;
      break;
#ifdef mpc860
    case SCC3_MINOR:    
      input_params.dlun = 2;
      break;
    case SCC4_MINOR:    
      input_params.dlun = 3;
      break;
#endif
    default:    
      input_params.dlun = 0;
      break;
  }
  
  _ISR_Disable( level );
  simask = m8xx.simask;

  /* Check for a char in the input FIFO using .CIO_STAT */
  asm volatile( "li 10,0x202\n\
                 mr 3, %0\n\
                 mr 4, %1\n\
                 sc"
    :: "g" (&input_params), "g" (&output_params) : "3", "4", "10" );

  if ( (output_params.status == 0) && output_params.u.stat.input_char_available) {
  
    /* Read the char and return it */
    input_params.inbuf = &c;
    input_params.nbytes_requested = 1;
  
    asm volatile( "li     10,0x200     /* Code for .CIO_READ */\n\
                   mr    3, %0         /* Address of input_params */\n\
                   mr    4, %1         /* Address of output_params */\n\
                   sc"             /* Call EPPCBUG */ 
      :: "g" (&input_params), "g" (&output_params) : "3", "4", "10" );

    if ( (output_params.status == 0) && output_params.u.read.nbytes_received)
      retval = (int)c;
  }
  
  m8xx.simask = simask;
  _ISR_Enable( level );
  return retval;
}


/*
 * _EPPCBug_pollWrite
 *
 *  Output buffer through EPPCBug. 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
 */
static int _EPPCBug_pollWrite(
  int minor,
  const char *buf,
  int len
)
{
  extern volatile m8xx_t m8xx;

  volatile int simask;
  int i, retval;
  ISR_Level level;
  
  struct {
    int clun;
    int dlun;
    const char * outbuf;
    int nbytes_to_output;
    int reserved;
  } volatile input_params;
  
  struct {
    int status;
    union {
      struct {
        int input_char_available;
        int output_possible;
        int break_detected;
        int modem_status;
      } stat;
      struct {
        int nbytes_sent;
      } write;
    } u;
  } volatile output_params;

  retval = -1;

  input_params.clun = 0;
  input_params.reserved = 0;
  
  switch( minor ) {
    case SMC1_MINOR:    
      input_params.dlun = 0;  /* Should be 4, but doesn't work with EPPCBug 1.1 */
      break;
    case SMC2_MINOR:    
      input_params.dlun = 5;
      break;
    case SCC2_MINOR:    
      input_params.dlun = 1;
      break;
#ifdef mpc860
    case SCC3_MINOR:    
      input_params.dlun = 2;
      break;
    case SCC4_MINOR:    
      input_params.dlun = 3;
      break;
#endif
    default:    
      input_params.dlun = 0;
      break;
  }

  i = 0;

  _ISR_Disable( level );
  simask = m8xx.simask;

  while (i < len) {
    /* Wait for space in the output buffer */
    do {
      /* Check for space in the output FIFO */
      asm volatile( "li 10,0x202        /* Code for .CIO_STAT */\n\
                     mr 3, %0           /* Address of input_params */\n\
                     mr 4, %1           /* Address of output_params */\n\
                     sc"            /* Call EPPCBUG */ 
        :: "g" (&input_params), "g" (&output_params) : "3", "4", "10" );

      if (output_params.status)
        goto error;
    } while (!output_params.u.stat.output_possible);

    /* Output the characters until done */
    input_params.outbuf = &buf[i];
    input_params.nbytes_to_output = len - i;
  
    asm volatile( "li 10,0x201          /* Code for .CIO_WRITE */\n\
                   mr 3, %0             /* Address of input_params */\n\
                   mr 4, %1             /* Address of output_params */\n\
                   sc"                  /* Call EPPCBUG */ 
      :: "g" (&input_params), "g" (&output_params) : "3", "4", "10" );

    if (output_params.status)
      goto error;

    i += output_params.u.write.nbytes_sent;
  }
  
  /* Return something */
  m8xx.simask = simask;
  _ISR_Enable( level );
  return RTEMS_SUCCESSFUL;

error:
  m8xx.simask = simask;
  _ISR_Enable( level );
  return -1;
}


/*
 *  do_poll_read
 *
 *  Input characters through polled I/O. 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!
 */
static 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;

#if NVRAM_CONFIGURE == 1

  int (*pollRead)( int minor );
  
  if ( (nvram->console_mode & 0x06) == 0x04 )
    pollRead = _EPPCBug_pollRead;
  else
    pollRead = m8xx_uart_pollRead;

  while( (c = (*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;

#else

#if UARTS_IO_MODE == 2
#define BSP_READ  _EPPCBug_pollRead
#else
#define BSP_READ  m8xx_uart_pollRead
#endif

  while( (c = BSP_READ(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;

#endif
}


/*
 *  do_poll_write
 *
 *  Output characters through polled I/O. 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!
 */
static 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';

#if NVRAM_CONFIGURE == 1

  int (*pollWrite)(int minor, const char *buf, int len);
  
  if ( (nvram->console_mode & 0x06) == 0x04 )
    pollWrite = _EPPCBug_pollWrite;
  else
    pollWrite = m8xx_uart_pollWrite;

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

#else

#if UARTS_IO_MODE == 2
#define BSP_WRITE _EPPCBug_pollWrite
#else
#define BSP_WRITE m8xx_uart_pollWrite
#endif

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

#endif
}


/*
 *  Print functions prototyped in bspIo.h
 */

static void _BSP_output_char( char c )
{
  char cr = '\r';
  
  /* 
   *  Can't rely on console_initialize having been called before this function
   *  is used, so it may fail unless output is done through EPPC-Bug.
   */
#if NVRAM_CONFIGURE == 1

  rtems_device_minor_number printk_minor;

  /* Use NVRAM info for configuration */
  printk_minor = (nvram->console_printk_port & 0x70) >> 4;
  if( (nvram->console_mode & 0x30) == 0x20 ) {
    _EPPCBug_pollWrite( printk_minor, &c, 1 );
    if( c == '\n' )
      _EPPCBug_pollWrite( printk_minor, &cr, 1 );
  }
  else {
    m8xx_uart_pollWrite( printk_minor, &c, 1 );
    if( c == '\n' )
      m8xx_uart_pollWrite( PRINTK_MINOR, &cr, 1 );
	}
	
#else  

#if PRINTK_IO_MODE == 2
#define PRINTK_WRITE _EPPCBug_pollWrite
#else
#define PRINTK_WRITE m8xx_uart_pollWrite
#endif

  PRINTK_WRITE( PRINTK_MINOR, &c, 1 );
  if( c == '\n' )
    PRINTK_WRITE( PRINTK_MINOR, &cr, 1 );
    
#endif
}

bd_t *eppcbugInfo= (bd_t *)0xdeadbeef;
bd_t fakeEppcBugInfo = {
  	0x42444944,		/* Should be 0x42444944 "BDID" */
	sizeof(bd_t),		/* Size of this structure */
	0,			/* revision of this structure */
	0,			/* EPPCbug date, i.e. 0x11061997 */
	0,			/* Memory start address */
	0x1000000,		/* Memory (end) size in bytes */
	0x28,			/* Internal Freq, in Hz */
	0,			/* Bus Freq, in Hz */
	0,			/* Boot device controller */
	0			/* Boot device logical dev */
};

#define EARLY_CONSOLE
#ifdef EARLY_CONSOLE

#define MBX_CSR1	((volatile unsigned char *)0xfa100000)
#define CSR1_COMEN	(unsigned char)0x02
#define PROFF_CONS	PROFF_SMC1
#define CPM_CR_CH_CONS	CPM_CR_CH_SMC1
#define SMC_INDEX	0

#include <bsp/commproc.h>

static cpm8xx_t	*cpmp = (cpm8xx_t *)&(((immap_t *)IMAP_ADDR)->im_cpm);

void
serial_init()
{
	volatile smc_t		*sp;
	volatile smc_uart_t	*up;
	volatile cbd_t	*tbdf,  *rbdf;
	volatile cpm8xx_t	*cp;
	unsigned int		dpaddr, memaddr;
	bd_t	*bd;

#if NVRAM_CONFIGURE == 1
	if ( ((nvram->console_mode & 0x06) != 0x04 ) || 
	     ((nvram->console_mode & 0x30) != 0x20 )) {
	  /*
	   * FIXME: refine this condition...
	   */
#endif
	bd = eppcbugInfo;
	
	cp = cpmp;
	sp = (smc_t*)&(cp->cp_smc[SMC_INDEX]);
	up = (smc_uart_t *)&cp->cp_dparam[PROFF_CONS];

	/* Disable transmitter/receiver.
	*/
	sp->smc_smcmr &= ~(SMCMR_REN | SMCMR_TEN);

	if (*MBX_CSR1 & CSR1_COMEN) {
		/* COM1 is enabled.  Initialize SMC1 and use it for
		 * the console port.
		 */