linux/arch/mips/au1000/common/puts.c

71 lines
2.1 KiB
C

/*
*
* BRIEF MODULE DESCRIPTION
* Low level uart routines to directly access a 16550 uart.
*
* Copyright 2001 MontaVista Software Inc.
* Author: MontaVista Software, Inc.
* ppopov@mvista.com or source@mvista.com
*
* 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 SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/types.h>
#include <asm/mach-au1x00/au1000.h>
#define SERIAL_BASE UART_BASE
#define SER_CMD 0x7
#define SER_DATA 0x1
#define TX_BUSY 0x20
#define TIMEOUT 0xffffff
#define SLOW_DOWN
static volatile unsigned long * const com1 = (unsigned long *)SERIAL_BASE;
#ifdef SLOW_DOWN
static inline void slow_down(void)
{
int k;
for (k=0; k<10000; k++);
}
#else
#define slow_down()
#endif
void
prom_putchar(const unsigned char c)
{
unsigned char ch;
int i = 0;
do {
ch = com1[SER_CMD];
slow_down();
i++;
if (i>TIMEOUT) {
break;
}
} while (0 == (ch & TX_BUSY));
com1[SER_DATA] = c;
}