[people/ms/u-boot.git] / drivers / serial / s3c4510b_uart.c

/*
 * 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;

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;

}
Commit	Line	Data
39539887 WD	1	/*
	2	* Copyright (c) 2004 Cucy Systems (http://www.cucy.com)
	3	* Curt Brune <curt@cucy.com>
	4	*
	5	* (C) Copyright 2004
	6	* DAVE Srl
	7	* http://www.dave-tech.it
	8	* http://www.wawnet.biz
	9	* mailto:info@wawnet.biz
	10	*
	11	* (C) Copyright 2002-2004
	12	* Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
	13	*
	14	* (C) Copyright 2002
	15	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	16	* Marius Groeger <mgroeger@sysgo.de>
	17	*
	18	* (C) Copyright 2002
	19	* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	20	* Alex Zuepke <azu@sysgo.de>
	21	*
	22	* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
	23	*
	24	* This program is free software; you can redistribute it and/or modify
	25	* it under the terms of the GNU General Public License as published by
	26	* the Free Software Foundation; either version 2 of the License, or
	27	* (at your option) any later version.
	28	*
	29	* This program is distributed in the hope that it will be useful,
	30	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	31	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	32	* GNU General Public License for more details.
	33	*
	34	* You should have received a copy of the GNU General Public License
	35	* along with this program; if not, write to the Free Software
	36	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	37	*
	38	* MODULE: $Id:$
	39	* Description: UART/Serial interface for Samsung S3C4510B SoC
	40	* Runtime Env: ARM7TDMI
	41	* Change History:
	42	* 03-02-04 Create (Curt Brune) curt@cucy.com
	43	*
	44	*/
	45
	46	#include <common.h>
	47
39539887 WD	48	#include <asm/hardware.h>
	49	#include "s3c4510b_uart.h"
	50
d87080b7 WD	51	DECLARE_GLOBAL_DATA_PTR;
d87080b7 WD	52
39539887 WD	53	static UART *uart;
	54
	55	/* flush serial input queue. returns 0 on success or negative error
	56	* number otherwise
	57	*/
	58	static int serial_flush_input(void)
	59	{
	60	volatile u32 tmp;
	61
	62	/* keep on reading as long as the receiver is not empty */
	63	while( uart->m_stat.bf.rxReady) {
	64	tmp = uart->m_rx;
	65	}
	66
	67	return 0;
	68	}
	69
	70
	71	/* flush output queue. returns 0 on success or negative error number
	72	* otherwise
	73	*/
	74	static int serial_flush_output(void)
	75	{
	76	/* wait until the transmitter is no longer busy */
	77	while( !uart->m_stat.bf.txBufEmpty);
	78
	79	return 0;
	80	}
	81
	82
	83	void serial_setbrg (void)
	84	{
39539887 WD	85	UART_LINE_CTRL ulctrl;
	86	UART_CTRL uctrl;
	87	UART_BAUD_DIV ubd;
	88
	89	serial_flush_output();
	90	serial_flush_input();
	91
	92	/* control register */
	93	uctrl.ui = 0x0;
	94	uctrl.bf.rxMode = 0x1;
	95	uctrl.bf.rxIrq = 0x0;
	96	uctrl.bf.txMode = 0x1;
	97	uctrl.bf.DSR = 0x0;
	98	uctrl.bf.sendBreak = 0x0;
	99	uctrl.bf.loopBack = 0x0;
	100	uart->m_ctrl.ui = uctrl.ui;
	101
	102	/* line control register */
	103	ulctrl.ui = 0x0;
	104	ulctrl.bf.wordLen = 0x3; /* 8 bit data */
	105	ulctrl.bf.nStop = 0x0; /* 1 stop bit */
	106	ulctrl.bf.parity = 0x0; /* no parity */
	107	ulctrl.bf.clk = 0x0; /* internal clock */
	108	ulctrl.bf.infra_red = 0x0; /* no infra_red */
	109	uart->m_lineCtrl.ui = ulctrl.ui;
	110
	111	ubd.ui = 0x0;
	112
	113	/* see table on page 10-15 in SAMSUNG S3C4510B manual */
	114	/* get correct divisor */
	115	switch(gd->baudrate) {
	116	case 1200: ubd.bf.cnt0 = 1301; break;
	117	case 2400: ubd.bf.cnt0 = 650; break;
	118	case 4800: ubd.bf.cnt0 = 324; break;
	119	case 9600: ubd.bf.cnt0 = 162; break;
	120	case 19200: ubd.bf.cnt0 = 80; break;
	121	case 38400: ubd.bf.cnt0 = 40; break;
	122	case 57600: ubd.bf.cnt0 = 26; break;
	123	case 115200: ubd.bf.cnt0 = 13; break;
	124	}
	125
	126	uart->m_baudDiv.ui = ubd.ui;
	127	uart->m_baudCnt = 0x0;
	128	uart->m_baudClk = 0x0;
	129
	130	}
	131
	132
	133	/*
	134	* Initialise the serial port with the given baudrate. The settings
	135	* are always 8 data bits, no parity, 1 stop bit, no start bits.
	136	*
	137	*/
	138	int serial_init (void)
	139	{
	140
	141	#if CONFIG_SERIAL1 == 1
	142	uart = (UART *)UART0_BASE;
	143	#elif CONFIG_SERIAL1 == 2
	144	uart = (UART *)UART1_BASE;
	145	#else
	146	#error CONFIG_SERIAL1 not equal to 1 or 2
	147	#endif
	148
149	serial_setbrg ();
150
151	return (0);
152	}
153
154
155	/*
156	* Output a single byte to the serial port.
157	*/
158	void serial_putc (const char c)
159	{
160	/* wait for room in the transmit FIFO */
161	while( !uart->m_stat.bf.txBufEmpty);
162
163	uart->m_tx = c;
164
165	/*
166	to be polite with serial console add a line feed
167	to the carriage return character
168	*/
169	if (c=='\n')
170	serial_putc('\r');
171	}
172
173	/*
174	* Test if an input byte is ready from the serial port. Returns non-zero on
175	* success, 0 otherwise.
176	*/
177	int serial_tstc (void)
178	{
179	return uart->m_stat.bf.rxReady;
180	}
181
182	/*
183	* Read a single byte from the serial port. Returns 1 on success, 0
184	* otherwise. When the function is succesfull, the character read is
185	* written into its argument c.
186	*/
187	int serial_getc (void)
188	{
189	int rv;
190
191	for(;;) {
192	rv = serial_tstc();
193
194	if (rv) {
195	return uart->m_rx & 0xFF;
196	}
197	}
198	}
199
200	void serial_puts (const char *s)
201	{
202	while (*s) {
203	serial_putc (*s++);
204	}
205
206	/* busy wait for tx complete */
207	while ( !uart->m_stat.bf.txComplete);
208
209	/* clear break */
210	uart->m_ctrl.bf.sendBreak = 0;
211
212	}