u-boot/cpu/lh7a40x/serial.c

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/*
* (C) Copyright 2002
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* 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>
#include <lh7a40x.h>
#if defined(CONFIG_CONSOLE_UART1)
# define UART_CONSOLE 1
#elif defined(CONFIG_CONSOLE_UART2)
# define UART_CONSOLE 2
#elif defined(CONFIG_CONSOLE_UART3)
# define UART_CONSOLE 3
#else
# error "No console configured ... "
#endif
void serial_setbrg (void)
{
DECLARE_GLOBAL_DATA_PTR;
lh7a40x_uart_t* uart = LH7A40X_UART_PTR(UART_CONSOLE);
int i;
unsigned int reg = 0;
/*
* userguide 15.1.2.4
*
* BAUDDIV is (UART_REF_FREQ/(16 X BAUD))-1
*
* UART_REF_FREQ = external system clock input / 2 (Hz)
* BAUD is desired baudrate (bits/s)
*
* NOTE: we add (divisor/2) to numerator to round for
* more precision
*/
reg = (((get_PLLCLK()/2) + ((16*gd->baudrate)/2)) / (16 * gd->baudrate)) - 1;
uart->brcon = reg;
for (i = 0; i < 100; i++);
}
/*
* 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)
{
lh7a40x_uart_t* uart = LH7A40X_UART_PTR(UART_CONSOLE);
/* UART must be enabled before writing to any config registers */
uart->con |= (UART_EN);
#ifdef CONFIG_CONSOLE_UART1
/* infrared disabled */
uart->con |= UART_SIRD;
#endif
/* loopback disabled */
uart->con &= ~(UART_LBE);
/* modem lines and tx/rx polarities */
uart->con &= ~(UART_MXP | UART_TXP | UART_RXP);
/* FIFO enable, N81 */
uart->fcon = (UART_WLEN_8 | UART_FEN | UART_STP2_1);
/* set baudrate */
serial_setbrg ();
/* enable rx interrupt */
uart->inten |= UART_RI;
return (0);
}
/*
* 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)
{
lh7a40x_uart_t* uart = LH7A40X_UART_PTR(UART_CONSOLE);
/* wait for character to arrive */
while (uart->status & UART_RXFE);
return(uart->data & 0xff);
}
#ifdef CONFIG_HWFLOW
static int hwflow = 0; /* turned off by default */
int hwflow_onoff(int on)
{
switch(on) {
case 0:
default:
break; /* return current */
case 1:
hwflow = 1; /* turn on */
break;
case -1:
hwflow = 0; /* turn off */
break;
}
return hwflow;
}
#endif
#ifdef CONFIG_MODEM_SUPPORT
static int be_quiet = 0;
void disable_putc(void)
{
be_quiet = 1;
}
void enable_putc(void)
{
be_quiet = 0;
}
#endif
/*
* Output a single byte to the serial port.
*/
void serial_putc (const char c)
{
lh7a40x_uart_t* uart = LH7A40X_UART_PTR(UART_CONSOLE);
#ifdef CONFIG_MODEM_SUPPORT
if (be_quiet)
return;
#endif
/* wait for room in the tx FIFO */
while (!(uart->status & UART_TXFE));
#ifdef CONFIG_HWFLOW
/* Wait for CTS up */
while(hwflow && !(uart->status & UART_CTS));
#endif
uart->data = c;
/* If \n, also do \r */
if (c == '\n')
serial_putc ('\r');
}
/*
* Test whether a character is in the RX buffer
*/
int serial_tstc (void)
{
lh7a40x_uart_t* uart = LH7A40X_UART_PTR(UART_CONSOLE);
return(!(uart->status & UART_RXFE));
}
void
serial_puts (const char *s)
{
while (*s) {
serial_putc (*s++);
}
}