diff options
Diffstat (limited to 'cpu/arm920t/s3c24x0/serial.c')
| -rw-r--r-- | cpu/arm920t/s3c24x0/serial.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/cpu/arm920t/s3c24x0/serial.c b/cpu/arm920t/s3c24x0/serial.c new file mode 100644 index 0000000..8327443 --- /dev/null +++ b/cpu/arm920t/s3c24x0/serial.c @@ -0,0 +1,182 @@ +/* + * (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> +#if defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB) + +#if defined(CONFIG_S3C2400) || defined(CONFIG_TRAB) +#include <s3c2400.h> +#elif defined(CONFIG_S3C2410) +#include <s3c2410.h> +#endif + +#ifdef CONFIG_SERIAL1 +#define UART_NR S3C24X0_UART0 + +#elif defined(CONFIG_SERIAL2) +# if defined(CONFIG_TRAB) +# error "TRAB supports only CONFIG_SERIAL1" +# endif +#define UART_NR S3C24X0_UART1 + +#elif defined(CONFIG_SERIAL3) +# if defined(CONFIG_TRAB) +# #error "TRAB supports only CONFIG_SERIAL1" +# endif +#define UART_NR S3C24X0_UART2 + +#else +#error "Bad: you didn't configure serial ..." +#endif + +void serial_setbrg (void) +{ + DECLARE_GLOBAL_DATA_PTR; + S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR); + int i; + unsigned int reg = 0; + + /* value is calculated so : (int)(PCLK/16./baudrate) -1 */ + reg = get_PCLK() / (16 * gd->baudrate) - 1; + + /* FIFO enable, Tx/Rx FIFO clear */ + uart->UFCON = 0x07; + uart->UMCON = 0x0; + /* Normal,No parity,1 stop,8 bit */ + uart->ULCON = 0x3; + /* + * tx=level,rx=edge,disable timeout int.,enable rx error int., + * normal,interrupt or polling + */ + uart->UCON = 0x245; + uart->UBRDIV = reg; + +#ifdef CONFIG_HWFLOW + uart->UMCON = 0x1; /* RTS up */ +#endif + 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) +{ + serial_setbrg (); + + 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) +{ + S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR); + + /* wait for character to arrive */ + while (!(uart->UTRSTAT & 0x1)); + + return uart->URXH & 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) +{ + S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR); +#ifdef CONFIG_MODEM_SUPPORT + if (be_quiet) + return; +#endif + + /* wait for room in the tx FIFO */ + while (!(uart->UTRSTAT & 0x2)); + +#ifdef CONFIG_HWFLOW + /* Wait for CTS up */ + while(hwflow && !(uart->UMSTAT & 0x1)) + ; +#endif + + uart->UTXH = 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) +{ + S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR); + + return uart->UTRSTAT & 0x1; +} + +void +serial_puts (const char *s) +{ + while (*s) { + serial_putc (*s++); + } +} + +#endif /* defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB) */ |