source: rtems/bsps/m68k/gen68340/console/m340uart.c @ d7d66d7

/*
 *  M68340/349 UART management tools
 */

/*
 *  Author:
 *  Geoffroy Montel
 *  France Telecom - CNET/DSM/TAM/CAT
 *  4, rue du Clos Courtel
 *  35512 CESSON-SEVIGNE
 *  FRANCE
 *
 *  e-mail: g_montel@yahoo.com
 *
 *  COPYRIGHT (c) 1989-1999.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */

#include <termios.h>
#include <bsp.h>
#include <rtems/libio.h>
#include <m68340.h>
#include <m340uart.h>
#include <stdarg.h>
#include <string.h>

/* this table shows compatible speed configurations for the MC68340:
   the first row shows baud rates for baud speed set 1
   the second row shows baud rates for baud speed set 2
   look at Motorola's MC68340 Integrated Processor User's Manual
   page 7-30 for more infos */

float m340_Baud_Rates_Table[16][2] = {
      { 50,    75 },
      { 110,   110 },
      { 134.5, 134.5 },
      { 200,   150 },
      { 300,   300 },
      { 600,   600 },
      { 1200,  1200 },
      { 1050,  2000 },
      { 2400,  2400 },
      { 4800,  4800 },
      { 7200,  1800 },
      { 9600,  9600 },
      { 38400, 19200 },
      { 76800, 38400 },
      { SCLK/16, SCLK/16},
      { SCLK,  SCLK },
};

/* config on both 340 channels */
uart_channel_config m340_uart_config[UART_NUMBER_OF_CHANNELS];

/*
 * Init UART table
 */

#define NOT_IMPLEMENTED_YET 0

/******************************************************
  Name: Init_UART_Table
  Input parameters: -
  Output parameters: -
  Description: Init the m340_uart_config
         THIS SHOULD NOT BE HERE!
         Its aim was to let the user configure
         UARTs for each application.
         As we can't pass args to the console
         driver initialisation routine at the
         moment, this was not done.
  ATTENTION: TERMIOS init presupposes that the channel
       baud rates is 9600/9600.
       -> risks when using IOCTL
 *****************************************************/
void Init_UART_Table(void)
{
  m340_uart_config[UART_CHANNEL_A].enable = TRUE;
  strcpy(m340_uart_config[UART_CHANNEL_A].name, UART_CONSOLE_NAME);
  m340_uart_config[UART_CHANNEL_A].parity_mode = m340_No_Parity;
  m340_uart_config[UART_CHANNEL_A].bits_per_char = m340_8bpc;
  m340_uart_config[UART_CHANNEL_A].rx_baudrate = 9600;
  m340_uart_config[UART_CHANNEL_A].tx_baudrate = 9600;
  m340_uart_config[UART_CHANNEL_A].rx_mode = UART_CRR;
  m340_uart_config[UART_CHANNEL_A].mode = UART_POLLING;

  m340_uart_config[UART_CHANNEL_A].termios.enable = TRUE;
  m340_uart_config[UART_CHANNEL_A].termios.rx_buffer_size = NOT_IMPLEMENTED_YET;
  m340_uart_config[UART_CHANNEL_A].termios.tx_buffer_size = NOT_IMPLEMENTED_YET;

  m340_uart_config[UART_CHANNEL_B].enable = FALSE;
  strcpy(m340_uart_config[UART_CHANNEL_B].name, UART_RAW_IO_NAME);
  m340_uart_config[UART_CHANNEL_B].parity_mode = m340_No_Parity;
  m340_uart_config[UART_CHANNEL_B].bits_per_char = m340_8bpc;
  m340_uart_config[UART_CHANNEL_B].rx_baudrate = 38400;
  m340_uart_config[UART_CHANNEL_B].tx_baudrate = 38400;
  m340_uart_config[UART_CHANNEL_B].rx_mode = UART_CRR;
  m340_uart_config[UART_CHANNEL_B].mode = UART_INTERRUPTS;

  m340_uart_config[UART_CHANNEL_B].termios.enable = TRUE;
  m340_uart_config[UART_CHANNEL_B].termios.rx_buffer_size = NOT_IMPLEMENTED_YET;
  m340_uart_config[UART_CHANNEL_B].termios.tx_buffer_size = NOT_IMPLEMENTED_YET;
}

/******************************************************
  Name: Find_Right_m340_UART_Channel_Config
  Input parameters: Send/Receive baud rates for a
        given channel
  Output parameters: UART compatible configs for this
        channel
  Description: returns which uart configurations fit
         Receiver Baud Rate and Transmitter Baud
         Rate for a given channel
         For instance, according to the
         m340_Baud_Rates_Table:
               - Output Speed = 50, Input Speed = 75
     is not a correct config, because
     50 bauds implies set 1 and 75 bauds
     implies set 2
               - Output Speed = 9600, Input Speed = 9600
     two correct configs for this:
     RCS=11, TCS=11, Set=1 or 2
 *****************************************************/
static t_baud_speed_table
Find_Right_m340_UART_Channel_Config(
  float ReceiverBaudRate,
  float TransmitterBaudRate
)
{
  t_baud_speed_table return_value;
  int i,j;

  struct {
    int cs;
    int set;
  } Receiver[2], Transmitter[2];

  int Receiver_nb_of_config = 0;
  int Transmitter_nb_of_config = 0;

  /* Receiver and Transmitter baud rates must be compatible, ie in the
   * same set.
   */

  /* search for configurations for ReceiverBaudRate
   * there can't be more than two (only two sets).
   */
  for (i=0;i<16;i++) {
    for (j=0;j<2;j++) {
      if (m340_Baud_Rates_Table[i][j]==ReceiverBaudRate) {
        Receiver[Receiver_nb_of_config].cs=i;
        Receiver[Receiver_nb_of_config].set=j;
        Receiver_nb_of_config++;
      }
    }
  }

  /* search for configurations for TransmitterBaudRate
   * there can't be more than two (only two sets)
   */
  for (i=0;i<16;i++) {
    for (j=0;j<2;j++) {
      if (m340_Baud_Rates_Table[i][j]==TransmitterBaudRate) {
        Transmitter[Transmitter_nb_of_config].cs=i;
        Transmitter[Transmitter_nb_of_config].set=j;
        Transmitter_nb_of_config++;
      }
    }
  }

  /* now check if there's a compatible config */
  return_value.nb=0;

 for (i=0; i<Receiver_nb_of_config; i++) {
   for (j=0;j<Transmitter_nb_of_config;j++) {
     if (Receiver[i].set == Transmitter[j].set) {
       return_value.baud_speed_table[return_value.nb].set = Receiver[i].set + 1;
       /* we want set 1 or set 2, not 0 or 1 */
       return_value.baud_speed_table[return_value.nb].rcs = Receiver[i].cs;
       return_value.baud_speed_table[return_value.nb].tcs = Transmitter[j].cs;
       return_value.nb++;
     }
   }
 }

 return return_value;
}

/******************************************************
  Name: Find_Right_m340_UART_Config
  Input parameters: Send/Receive baud rates for both
        channels
  Output parameters: UART compatible configs for
         BOTH channels
  Description: returns which uart configurations fit
         Receiver Baud Rate and Transmitter Baud
         Rate for both channels
         For instance, if we want 9600/38400 on
         channel A and 9600/19200 on channel B,
         this is not a good m340 uart config
         (channel A needs set 1 and channel B
         needs set 2)
 *****************************************************/
t_baud_speed_table
Find_Right_m340_UART_Config(
  float ChannelA_ReceiverBaudRate,
  float ChannelA_TransmitterBaudRate,
  uint8_t         enableA,
  float ChannelB_ReceiverBaudRate,
  float ChannelB_TransmitterBaudRate,
  uint8_t         enableB
)
{
  t_baud_speed_table tableA, tableB;
  t_baud_speed_table return_value, tmp;
  int i,j;

  memset( &return_value, '\0', sizeof(return_value) );
  return_value.nb=0;

  if (enableA && enableB) {
    tableA = Find_Right_m340_UART_Channel_Config(
               ChannelA_ReceiverBaudRate, ChannelA_TransmitterBaudRate);
    tableB = Find_Right_m340_UART_Channel_Config(
               ChannelB_ReceiverBaudRate, ChannelB_TransmitterBaudRate);

    for (i=0;i<tableA.nb;i++) {
      for (j=0;j<tableB.nb;j++) {
        if (tableA.baud_speed_table[i].set==tableB.baud_speed_table[j].set) {
          return_value.baud_speed_table[UART_CHANNEL_A].set =
            tableA.baud_speed_table[i].set;
          return_value.baud_speed_table[UART_CHANNEL_A].rcs =
            tableA.baud_speed_table[i].rcs;
          return_value.baud_speed_table[UART_CHANNEL_A].tcs =
            tableA.baud_speed_table[i].tcs;
          return_value.baud_speed_table[UART_CHANNEL_B].set =
            tableB.baud_speed_table[j].set;
          return_value.baud_speed_table[UART_CHANNEL_B].rcs =
            tableB.baud_speed_table[j].rcs;
          return_value.baud_speed_table[UART_CHANNEL_B].tcs =
            tableB.baud_speed_table[j].tcs;
          return_value.nb=2;
          break;
        }
      }
    }
    return return_value;
  }

  if (enableA) {
    return_value = Find_Right_m340_UART_Channel_Config(
          ChannelA_ReceiverBaudRate, ChannelA_TransmitterBaudRate);
    return return_value;
  }

  if (enableB) {
    tmp = Find_Right_m340_UART_Channel_Config(
      ChannelB_ReceiverBaudRate, ChannelB_TransmitterBaudRate);
    if (tmp.nb!=0) {
      return_value.nb = 2;
      return_value.baud_speed_table[1].set = tmp.baud_speed_table[0].set;
      return_value.baud_speed_table[1].rcs = tmp.baud_speed_table[0].rcs;
      return_value.baud_speed_table[1].tcs = tmp.baud_speed_table[0].tcs;
    }
  }
  return return_value;
}


/*
 * very low level fmted output
 */
extern void dbug_out_char( int minor, int ch );
extern int dbug_in_char( int minor );
extern int dbug_char_present( int minor );

/******************************************************
  Name: dbugRead
  Input parameters: channel
  Output parameters: char read
  Description: polled read
 *****************************************************/
int dbugRead (int minor)
{
  if (dbug_char_present(minor) == 0)
    return -1;
  return dbug_in_char(minor);
}

/******************************************************
  Name: dbugWrite
  Input parameters: channel, buffer and its length
  Output parameters: always successfull
  Description: polled write
 *****************************************************/
ssize_t dbugWrite (int minor, const char *buf, size_t len)
{
  static char txBuf;
  size_t retval = len;

  while (len--) {
     txBuf = *buf++;
          dbug_out_char( minor, (int)txBuf );
  }
  return retval;
}