/*********************************************************************** * * Copyright (C) 2004 by FS Forth-Systeme GmbH. * All rights reserved. * * $Id: ns9750_serial.c,v 1.1 2004/02/16 10:37:20 mpietrek Exp $ * @Author: Markus Pietrek * @Descr: Serial driver for the NS9750. Only one UART is supported yet. * @References: [1] NS9750 Hardware Reference/December 2003 * @TODO: Implement Character GAP Timer when chip is fixed for PLL bypass * * 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>#ifdef CFG_NS9750_UART#include "ns9750_bbus.h"	/* for GPIOs */#include "ns9750_ser.h"		/* for serial configuration */DECLARE_GLOBAL_DATA_PTR;#if !defined(CONFIG_CONS_INDEX)#error "No console index specified."#endif#define CONSOLE CONFIG_CONS_INDEXstatic unsigned int calcBitrateRegister( void );static unsigned int calcRxCharGapRegister( void );static char cCharsAvailable; /* Numbers of chars in unCharCache */static unsigned int unCharCache; /* unCharCache is only valid if				  * cCharsAvailable > 0 *//*********************************************************************** * @Function: serial_init * @Return: 0 * @Descr: configures GPIOs and UART. Requires BBUS Master Reset turned off ***********************************************************************/int serial_init( void ){	unsigned int aunGPIOTxD[] = { 0, 8, 40, 44 };	unsigned int aunGPIORxD[] = { 1, 9, 41, 45 };	cCharsAvailable = 0;	/* configure TxD and RxD pins for their special function */	set_gpio_cfg_reg_val( aunGPIOTxD[ CONSOLE ],			      NS9750_GPIO_CFG_FUNC_0 | NS9750_GPIO_CFG_OUTPUT );	set_gpio_cfg_reg_val( aunGPIORxD[ CONSOLE ],			      NS9750_GPIO_CFG_FUNC_0 | NS9750_GPIO_CFG_INPUT );	/* configure serial engine */	*get_ser_reg_addr_channel( NS9750_SER_CTRL_A, CONSOLE ) =		NS9750_SER_CTRL_A_CE |		NS9750_SER_CTRL_A_STOP |		NS9750_SER_CTRL_A_WLS_8;	serial_setbrg();	*get_ser_reg_addr_channel( NS9750_SER_CTRL_B, CONSOLE ) =		NS9750_SER_CTRL_B_RCGT;	return 0;}/*********************************************************************** * @Function: serial_putc * @Return: n/a * @Descr: writes one character to the FIFO. Blocks until FIFO is not full ***********************************************************************/void serial_putc( const char c ){	if (c == '\n')		serial_putc( '\r' );	while (!(*get_ser_reg_addr_channel( NS9750_SER_STAT_A, CONSOLE) &		 NS9750_SER_STAT_A_TRDY ) ) {		/* do nothing, wait for characters in FIFO sent */	}	*(volatile char*) get_ser_reg_addr_channel( NS9750_SER_FIFO,						    CONSOLE) = c;}/*********************************************************************** * @Function: serial_puts * @Return: n/a * @Descr: writes non-zero string to the FIFO. ***********************************************************************/void serial_puts( const char *s ){	while (*s) {		serial_putc( *s++ );	}}/*********************************************************************** * @Function: serial_getc * @Return: the character read * @Descr: performs only 8bit accesses to the FIFO. No error handling ***********************************************************************/int serial_getc( void ){	int i;	while (!serial_tstc() ) {		/* do nothing, wait for incoming characters */	}	/*  at least one character in unCharCache */	i = (int) (unCharCache & 0xff);	unCharCache >>= 8;	cCharsAvailable--;	return i;}/*********************************************************************** * @Function: serial_tstc * @Return: 0 if no input available, otherwise != 0 * @Descr: checks for incoming FIFO not empty. Stores the incoming chars in *	   unCharCache and the numbers of characters in cCharsAvailable ***********************************************************************/int serial_tstc( void ){	unsigned int unRegCache;	if ( cCharsAvailable )		return 1;	unRegCache = *get_ser_reg_addr_channel( NS9750_SER_STAT_A,CONSOLE );	if( unRegCache & NS9750_SER_STAT_A_RBC ) {		*get_ser_reg_addr_channel( NS9750_SER_STAT_A, CONSOLE ) =			NS9750_SER_STAT_A_RBC;		unRegCache = *get_ser_reg_addr_channel( NS9750_SER_STAT_A,							CONSOLE );	}	if ( unRegCache & NS9750_SER_STAT_A_RRDY ) {		cCharsAvailable = (unRegCache & NS9750_SER_STAT_A_RXFDB_MA)>>20;		if ( !cCharsAvailable )			cCharsAvailable = 4;		unCharCache = *get_ser_reg_addr_channel( NS9750_SER_FIFO,							 CONSOLE );		return 1;	}	/* no chars available */	return 0;}void serial_setbrg( void ){	*get_ser_reg_addr_channel( NS9750_SER_BITRATE, CONSOLE ) =		calcBitrateRegister();	*get_ser_reg_addr_channel( NS9750_SER_RX_CHAR_TIMER, CONSOLE ) =		calcRxCharGapRegister();}/*********************************************************************** * @Function: calcBitrateRegister * @Return: value for the serial bitrate register * @Descr: register value depends on clock frequency and baudrate ***********************************************************************/static unsigned int calcBitrateRegister( void ){	return ( NS9750_SER_BITRATE_EBIT |		 NS9750_SER_BITRATE_CLKMUX_BCLK |		 NS9750_SER_BITRATE_TMODE |		 NS9750_SER_BITRATE_TCDR_16 |		 NS9750_SER_BITRATE_RCDR_16 |		 ( ( ( ( CONFIG_SYS_CLK_FREQ / 8 ) / /* BBUS clock,[1] Fig. 38 */		       ( gd->baudrate * 16 ) ) - 1 ) &		   NS9750_SER_BITRATE_N_MA ) );}/*********************************************************************** * @Function: calcRxCharGapRegister * @Return: value for the character gap timer register * @Descr: register value depends on clock frequency and baudrate. Currently 0 *	   is used as there is a bug with the gap timer in PLL bypass mode. ***********************************************************************/static unsigned int calcRxCharGapRegister( void ){	return NS9750_SER_RX_CHAR_TIMER_TRUN;}#endif /* CFG_NS9750_UART */