board/bmw/ns16550.c

   1 /*
   2  * COM1 NS16550 support
   3  * originally from linux source (arch/ppc/boot/ns16550.c)
   4  * modified to use CONFIG_SYS_ISA_MEM and new defines
   5  */
   6
   7 #include <config.h>
   8 #include "ns16550.h"
   9
  10 typedef struct NS16550 *NS16550_t;
  11
  12 const NS16550_t COM_PORTS[] =
  13         { (NS16550_t) ((CONFIG_SYS_EUMB_ADDR) + 0x4500),
  14 (NS16550_t) ((CONFIG_SYS_EUMB_ADDR) + 0x4600) };
  15
  16 volatile struct NS16550 *NS16550_init (int chan, int baud_divisor)
  17 {
  18         volatile struct NS16550 *com_port;
  19
  20         com_port = (struct NS16550 *) COM_PORTS[chan];
  21         com_port->ier = 0x00;
  22         com_port->lcr = LCR_BKSE;       /* Access baud rate */
  23         com_port->dll = baud_divisor & 0xff;    /* 9600 baud */
  24         com_port->dlm = (baud_divisor >> 8) & 0xff;
  25         com_port->lcr = LCR_8N1;        /* 8 data, 1 stop, no parity */
  26         com_port->mcr = MCR_RTS;        /* RTS/DTR */
  27         com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR;      /* Clear & enable FIFOs */
  28         return (com_port);
  29 }
  30
  31 void NS16550_reinit (volatile struct NS16550 *com_port, int baud_divisor)
  32 {
  33         com_port->ier = 0x00;
  34         com_port->lcr = LCR_BKSE;       /* Access baud rate */
  35         com_port->dll = baud_divisor & 0xff;    /* 9600 baud */
  36         com_port->dlm = (baud_divisor >> 8) & 0xff;
  37         com_port->lcr = LCR_8N1;        /* 8 data, 1 stop, no parity */
  38         com_port->mcr = MCR_RTS;        /* RTS/DTR */
  39         com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR;      /* Clear & enable FIFOs */
  40 }
  41
  42 void NS16550_putc (volatile struct NS16550 *com_port, unsigned char c)
  43 {
  44         while ((com_port->lsr & LSR_THRE) == 0);
  45         com_port->thr = c;
  46 }
  47
  48 unsigned char NS16550_getc (volatile struct NS16550 *com_port)
  49 {
  50         while ((com_port->lsr & LSR_DR) == 0);
  51         return (com_port->rbr);
  52 }
  53
  54 int NS16550_tstc (volatile struct NS16550 *com_port)
  55 {
  56         return ((com_port->lsr & LSR_DR) != 0);
  57 }