68 lines
2 KiB
C
68 lines
2 KiB
C
/*
|
|
*
|
|
* BRIEF MODULE DESCRIPTION
|
|
* Low level UART routines to directly access Alchemy UART.
|
|
*
|
|
* Copyright 2001, 2008 MontaVista Software Inc.
|
|
* Author: MontaVista Software, Inc. <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 <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;
|
|
}
|