board/Marvell/common/ns16550.c

   1 /*
   2  * COM1 NS16550 support
   3  * originally from linux source (arch/powerpc/boot/ns16550.c)
   4  * modified to use CONFIG_SYS_ISA_MEM and new defines
   5  *
   6  * further modified by Josh Huber <huber@mclx.com> to support
   7  * the DUART on the Galileo Eval board. (db64360)
   8  */
   9
  10 #include <config.h>
  11 #include "ns16550.h"
  12
  13 #ifdef ZUMA_NTL
  14 /* no 16550 device */
  15 #else
  16 const NS16550_t COM_PORTS[] = { (NS16550_t) (CONFIG_SYS_DUART_IO + 0),
  17         (NS16550_t) (CONFIG_SYS_DUART_IO + 0x20)
  18 };
  19
  20 volatile struct NS16550 *NS16550_init (int chan, int baud_divisor)
  21 {
  22         volatile struct NS16550 *com_port;
  23
  24         com_port = (struct NS16550 *) COM_PORTS[chan];
  25         com_port->ier = 0x00;
  26         com_port->lcr = LCR_BKSE;       /* Access baud rate */
  27         com_port->dll = baud_divisor & 0xff;    /* 9600 baud */
  28         com_port->dlm = (baud_divisor >> 8) & 0xff;
  29         com_port->lcr = LCR_8N1;        /* 8 data, 1 stop, no parity */
  30         com_port->mcr = MCR_DTR | MCR_RTS;      /* RTS/DTR */
  31
  32         /* Clear & enable FIFOs */
  33         com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR;
  34         return (com_port);
  35 }
  36
  37 void NS16550_reinit (volatile struct NS16550 *com_port, int baud_divisor)
  38 {
  39         com_port->ier = 0x00;
  40         com_port->lcr = LCR_BKSE;       /* Access baud rate */
  41         com_port->dll = baud_divisor & 0xff;    /* 9600 baud */
  42         com_port->dlm = (baud_divisor >> 8) & 0xff;
  43         com_port->lcr = LCR_8N1;        /* 8 data, 1 stop, no parity */
  44         com_port->mcr = MCR_DTR | MCR_RTS;      /* RTS/DTR */
  45
  46         /* Clear & enable FIFOs */
  47         com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR;
  48 }
  49
  50 void NS16550_putc (volatile struct NS16550 *com_port, unsigned char c)
  51 {
  52         while ((com_port->lsr & LSR_THRE) == 0);
  53         com_port->thr = c;
  54 }
  55
  56 unsigned char NS16550_getc (volatile struct NS16550 *com_port)
  57 {
  58         while ((com_port->lsr & LSR_DR) == 0);
  59         return (com_port->rbr);
  60 }
  61
  62 int NS16550_tstc (volatile struct NS16550 *com_port)
  63 {
  64         return ((com_port->lsr & LSR_DR) != 0);
  65 }
  66 #endif