u-boot/cpu/nios/serial.c

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/*
* (C) Copyright 2003, Psyent Corporation <www.psyent.com>
* Scott McNutt <smcnutt@psyent.com>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <watchdog.h>
#include <nios-io.h>
/*------------------------------------------------------------------
* JTAG acts as the serial port
*-----------------------------------------------------------------*/
#if defined(CONFIG_CONSOLE_JTAG)
static nios_jtag_t *jtag = (nios_jtag_t *)CFG_NIOS_CONSOLE;
void serial_setbrg( void ){ return; }
int serial_init( void ) { return(0);}
void serial_putc (char c)
{
while ((jtag->txcntl & NIOS_JTAG_TRDY) != 0)
WATCHDOG_RESET ();
jtag->txcntl = NIOS_JTAG_TRDY | (unsigned char)c;
}
void serial_puts (const char *s)
{
while (*s != 0)
serial_putc (*s++);
}
int serial_tstc (void)
{
return (jtag->rxcntl & NIOS_JTAG_RRDY);
}
int serial_getc (void)
{
int c;
while (serial_tstc() == 0)
WATCHDOG_RESET ();
c = jtag->rxcntl & 0x0ff;
jtag->rxcntl = 0;
return (c);
}
/*------------------------------------------------------------------
* UART the serial port
*-----------------------------------------------------------------*/
#else
static nios_uart_t *uart = (nios_uart_t *)CFG_NIOS_CONSOLE;
#if defined(CFG_NIOS_FIXEDBAUD)
/* Everything's already setup for fixed-baud PTF
* assignment
*/
void serial_setbrg (void){ return; }
int serial_init (void) { return (0);}
#else
void serial_setbrg (void)
{
DECLARE_GLOBAL_DATA_PTR;
unsigned div;
div = (CONFIG_SYS_CLK_FREQ/gd->baudrate)-1;
uart->divisor = div;
return;
}
int serial_init (void)
{
serial_setbrg ();
return (0);
}
#endif /* CFG_NIOS_FIXEDBAUD */
/*-----------------------------------------------------------------------
* UART CONSOLE
*---------------------------------------------------------------------*/
void serial_putc (char c)
{
if (c == '\n')
serial_putc ('\r');
while ((uart->status & NIOS_UART_TRDY) == 0)
WATCHDOG_RESET ();
uart->txdata = (unsigned char)c;
}
void serial_puts (const char *s)
{
while (*s != 0) {
serial_putc (*s++);
}
}
int serial_tstc (void)
{
return (uart->status & NIOS_UART_RRDY);
}
int serial_getc (void)
{
while (serial_tstc () == 0)
WATCHDOG_RESET ();
return( uart->rxdata & 0x00ff );
}
#endif /* CONFIG_JTAG_CONSOLE */