drivers/serial/altera_jtag_uart.c

   1 /*
   2  * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
   3  * Scott McNutt <smcnutt@psyent.com>
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25 #include <watchdog.h>
  26 #include <asm/io.h>
  27 #include <nios2-io.h>
  28
  29 DECLARE_GLOBAL_DATA_PTR;
  30
  31 /*------------------------------------------------------------------
  32  * JTAG acts as the serial port
  33  *-----------------------------------------------------------------*/
  34 static nios_jtag_t *jtag = (nios_jtag_t *)CONFIG_SYS_NIOS_CONSOLE;
  35
  36 void serial_setbrg( void ){ return; }
  37 int serial_init( void ) { return(0);}
  38
  39 void serial_putc (char c)
  40 {
  41         while (NIOS_JTAG_WSPACE ( readl (&jtag->control)) == 0)
  42                 WATCHDOG_RESET ();
  43         writel ((unsigned char)c, &jtag->data);
  44 }
  45
  46 void serial_puts (const char *s)
  47 {
  48         while (*s != 0)
  49                 serial_putc (*s++);
  50 }
  51
  52 int serial_tstc (void)
  53 {
  54         return ( readl (&jtag->control) & NIOS_JTAG_RRDY);
  55 }
  56
  57 int serial_getc (void)
  58 {
  59         int c;
  60         unsigned val;
  61
  62         while (1) {
  63                 WATCHDOG_RESET ();
  64                 val = readl (&jtag->data);
  65                 if (val & NIOS_JTAG_RVALID)
  66                         break;
  67         }
  68         c = val & 0x0ff;
  69         return (c);
  70 }