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Diffstat (limited to 'cpu/lh7a40x/serial.c')
| -rw-r--r-- | cpu/lh7a40x/serial.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/cpu/lh7a40x/serial.c b/cpu/lh7a40x/serial.c new file mode 100644 index 0000000..241d568 --- /dev/null +++ b/cpu/lh7a40x/serial.c @@ -0,0 +1,183 @@ +/* + * (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_PTR(uart,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_PTR(uart,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_PTR(uart,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_PTR(uart,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_PTR(uart,UART_CONSOLE); + + return(!(uart->status & UART_RXFE)); +} + +void +serial_puts (const char *s) +{ + while (*s) { + serial_putc (*s++); + } +} |