blob: bef9ccbab232af349fd6139a3922fd0a27ca0722 [file] [log] [blame]
/*
* Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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 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., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/** @file
*
* Serial console
*
*/
#include <stddef.h>
#include <string.h>
#include <ipxe/init.h>
#include <ipxe/uart.h>
#include <ipxe/console.h>
#include <ipxe/serial.h>
#include <config/console.h>
#include <config/serial.h>
/* Set default console usage if applicable */
#if ! ( defined ( CONSOLE_SERIAL ) && CONSOLE_EXPLICIT ( CONSOLE_SERIAL ) )
#undef CONSOLE_SERIAL
#define CONSOLE_SERIAL ( CONSOLE_USAGE_ALL & ~CONSOLE_USAGE_LOG )
#endif
/* UART port number */
#ifdef COMCONSOLE
#define CONSOLE_PORT COMCONSOLE
#else
#define CONSOLE_PORT 0
#endif
/* UART baud rate */
#ifdef COMPRESERVE
#define CONSOLE_BAUD 0
#else
#define CONSOLE_BAUD COMSPEED
#endif
/* UART line control register value */
#ifdef COMPRESERVE
#define CONSOLE_LCR 0
#else
#define CONSOLE_LCR UART_LCR_WPS ( COMDATA, COMPARITY, COMSTOP )
#endif
/** Serial console UART */
struct uart serial_console;
/**
* Print a character to serial console
*
* @v character Character to be printed
*/
static void serial_putchar ( int character ) {
/* Do nothing if we have no UART */
if ( ! serial_console.base )
return;
/* Transmit character */
uart_transmit ( &serial_console, character );
}
/**
* Get character from serial console
*
* @ret character Character read from console
*/
static int serial_getchar ( void ) {
uint8_t data;
/* Do nothing if we have no UART */
if ( ! serial_console.base )
return 0;
/* Wait for data to be ready */
while ( ! uart_data_ready ( &serial_console ) ) {}
/* Receive data */
data = uart_receive ( &serial_console );
/* Strip any high bit and convert DEL to backspace */
data &= 0x7f;
if ( data == 0x7f )
data = 0x08;
return data;
}
/**
* Check for character ready to read from serial console
*
* @ret True Character available to read
* @ret False No character available to read
*/
static int serial_iskey ( void ) {
/* Do nothing if we have no UART */
if ( ! serial_console.base )
return 0;
/* Check UART */
return uart_data_ready ( &serial_console );
}
/** Serial console */
struct console_driver serial_console_driver __console_driver = {
.putchar = serial_putchar,
.getchar = serial_getchar,
.iskey = serial_iskey,
.usage = CONSOLE_SERIAL,
};
/** Initialise serial console */
static void serial_init ( void ) {
int rc;
/* Do nothing if we have no default port */
if ( ! CONSOLE_PORT )
return;
/* Select UART */
if ( ( rc = uart_select ( &serial_console, CONSOLE_PORT ) ) != 0 ) {
DBG ( "Could not select UART %d: %s\n",
CONSOLE_PORT, strerror ( rc ) );
return;
}
/* Initialise UART */
if ( ( rc = uart_init ( &serial_console, CONSOLE_BAUD,
CONSOLE_LCR ) ) != 0 ) {
DBG ( "Could not initialise UART %d baud %d LCR %#02x: %s\n",
CONSOLE_PORT, CONSOLE_BAUD, CONSOLE_LCR, strerror ( rc ));
return;
}
}
/**
* Shut down serial console
*
* @v flags Shutdown flags
*/
static void serial_shutdown ( int flags __unused ) {
/* Do nothing if we have no UART */
if ( ! serial_console.base )
return;
/* Flush any pending output */
uart_flush ( &serial_console );
/* Leave console enabled; it's still usable */
}
/** Serial console initialisation function */
struct init_fn serial_console_init_fn __init_fn ( INIT_CONSOLE ) = {
.initialise = serial_init,
};
/** Serial console startup function */
struct startup_fn serial_startup_fn __startup_fn ( STARTUP_EARLY ) = {
.name = "serial",
.shutdown = serial_shutdown,
};