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/*
* Copyright (c) 2004 Cucy Systems (http://www.cucy.com)
* Curt Brune <curt@cucy.com>
*
* (C) Copyright 2004
* DAVE Srl
* http://www.dave-tech.it
* http://www.wawnet.biz
* mailto:info@wawnet.biz
*
* (C) Copyright 2002-2004
* Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
*
* 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
*
* MODULE: $Id:$
* Description: UART/Serial interface for Samsung S3C4510B SoC
* Runtime Env: ARM7TDMI
* Change History:
* 03-02-04 Create (Curt Brune) curt@cucy.com
*
*/
#include <common.h>
#include <asm/hardware.h>
#include "s3c4510b_uart.h"
DECLARE_GLOBAL_DATA_PTR;
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static UART *uart;
/* flush serial input queue. returns 0 on success or negative error
* number otherwise
*/
static int serial_flush_input(void)
{
volatile u32 tmp;
/* keep on reading as long as the receiver is not empty */
while( uart->m_stat.bf.rxReady) {
tmp = uart->m_rx;
}
return 0;
}
/* flush output queue. returns 0 on success or negative error number
* otherwise
*/
static int serial_flush_output(void)
{
/* wait until the transmitter is no longer busy */
while( !uart->m_stat.bf.txBufEmpty);
return 0;
}
void serial_setbrg (void)
{
UART_LINE_CTRL ulctrl;
UART_CTRL uctrl;
UART_BAUD_DIV ubd;
serial_flush_output();
serial_flush_input();
/* control register */
uctrl.ui = 0x0;
uctrl.bf.rxMode = 0x1;
uctrl.bf.rxIrq = 0x0;
uctrl.bf.txMode = 0x1;
uctrl.bf.DSR = 0x0;
uctrl.bf.sendBreak = 0x0;
uctrl.bf.loopBack = 0x0;
uart->m_ctrl.ui = uctrl.ui;
/* line control register */
ulctrl.ui = 0x0;
ulctrl.bf.wordLen = 0x3; /* 8 bit data */
ulctrl.bf.nStop = 0x0; /* 1 stop bit */
ulctrl.bf.parity = 0x0; /* no parity */
ulctrl.bf.clk = 0x0; /* internal clock */
ulctrl.bf.infra_red = 0x0; /* no infra_red */
uart->m_lineCtrl.ui = ulctrl.ui;
ubd.ui = 0x0;
/* see table on page 10-15 in SAMSUNG S3C4510B manual */
/* get correct divisor */
switch(gd->baudrate) {
case 1200: ubd.bf.cnt0 = 1301; break;
case 2400: ubd.bf.cnt0 = 650; break;
case 4800: ubd.bf.cnt0 = 324; break;
case 9600: ubd.bf.cnt0 = 162; break;
case 19200: ubd.bf.cnt0 = 80; break;
case 38400: ubd.bf.cnt0 = 40; break;
case 57600: ubd.bf.cnt0 = 26; break;
case 115200: ubd.bf.cnt0 = 13; break;
}
uart->m_baudDiv.ui = ubd.ui;
uart->m_baudCnt = 0x0;
uart->m_baudClk = 0x0;
}
/*
* Initialise the serial port with the given baudrate. The settings
* are always 8 data bits, no parity, 1 stop bit, no start bits.
*
*/
int serial_init (void)
{
#if CONFIG_SERIAL1 == 1
uart = (UART *)UART0_BASE;
#elif CONFIG_SERIAL1 == 2
uart = (UART *)UART1_BASE;
#else
#error CONFIG_SERIAL1 not equal to 1 or 2
#endif
serial_setbrg ();
return (0);
}
/*
* Output a single byte to the serial port.
*/
void serial_putc (const char c)
{
/* wait for room in the transmit FIFO */
while( !uart->m_stat.bf.txBufEmpty);
uart->m_tx = c;
/*
to be polite with serial console add a line feed
to the carriage return character
*/
if (c=='\n')
serial_putc('\r');
}
/*
* Test if an input byte is ready from the serial port. Returns non-zero on
* success, 0 otherwise.
*/
int serial_tstc (void)
{
return uart->m_stat.bf.rxReady;
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
int serial_getc (void)
{
int rv;
for(;;) {
rv = serial_tstc();
if (rv) {
return uart->m_rx & 0xFF;
}
}
}
void serial_puts (const char *s)
{
while (*s) {
serial_putc (*s++);
}
/* busy wait for tx complete */
while ( !uart->m_stat.bf.txComplete);
/* clear break */
uart->m_ctrl.bf.sendBreak = 0;
}