[U-Boot-Users] Fixed CD in serial.c, AT91RM9200

Kögler Peter p.koegler at el-me.de
Tue Jul 13 09:13:22 CEST 2004


Hello all,
is there a reason why the clock divisor in the baudrate generator register
(us->US_BRGR) is set to a fixed value in serial_setbrg(void):

us->US_BRGR = CFG_AT91C_BRGR_DIVISOR


I changed the implementation of serial_setbrg(void) and i can now opperate
at higher baudrates. (change baudrate with loadb).

Here is my version:

void serial_setbrg (void)
{
  DECLARE_GLOBAL_DATA_PTR;
  int baudrate, baudRateGenDiv,i;
  unsigned long baudrate_table[] = CFG_BAUDRATE_TABLE;
  int n_baudrates = (sizeof(baudrate_table) / sizeof(baudrate_table[0]));

  baudrate = gd->baudrate;
  
  //check if value is supported
  for (i=0; i<n_baudrates; ++i) 
  {
    if (baudrate == baudrate_table[i])
    {
      baudRateGenDiv = AT91C_MASTER_CLOCK / baudrate / 16;
      //printf ("## Switched baudrate to %dbps.\n", baudrate);
      break;
    }
  }
  
  if (baudRateGenDiv==0)
  {
    //using default value
    baudRateGenDiv = CFG_AT91C_BRGR_DIVISOR;
    printf ("## Baudrate %dbps not supported using default baudrate
%dbps.\n", baudrate, CONFIG_BAUDRATE);
  }
  
  us->US_BRGR = baudRateGenDiv;
}

If you agree with my changes i can provide a patch.

wbr

Peter




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