/*-
* Copyright (c) 2005, Kohsuke Ohtani
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* gdb_glue.c - serial data transfer routine for gdb stub
*/
#include <kernel.h>
#include <cpu.h>
/* Serial port registers */
#define COM_PORT 0x3F8
#define RBR 0 /* 3F8 Receive buffer register. */
#define THR 0 /* 3F8 Transmit holding register. */
#define IER 1 /* 3F9 Interrupt enable register. */
#define FCR 2 /* 3FA FIFO control register. */
#define IIR 2 /* 3FA Interrupt identification register. */
#define LCR 3 /* 3FB Line control register. */
#define MCR 4 /* 3FC Modem control register. */
#define LSR 5 /* 3FD Line status register. */
#define MSR 6 /* 3FE Modem status register. */
#define DLL 0 /* 3F8 Divisor latch LSB (LCR[7] = 1). */
#define DLM 1 /* 3F9 Divisor latch MSB (LCR[7] = 1). */
int
serial_getchar(void)
{
while (!(inb(COM_PORT + LSR) & 0x01));
return inb(COM_PORT + RBR);
}
void
serial_putchar(int ch)
{
while (!(inb(COM_PORT + LSR) & 0x20));
outb((char)ch, COM_PORT + THR);
}
int
serial_init(void)
{
if (inb(COM_PORT + LSR) == 0xFF)
return -1; /* Serial port is disabled */
outb(0x00, COM_PORT + IER); /* Disable all interrupt */
outb(0x80, COM_PORT + LCR); /* Access baud rate */
outb(0x01, COM_PORT + DLL); /* Baud rate = 115200 */
outb(0x00, COM_PORT + DLM);
outb(0x03, COM_PORT + LCR); /* N, 8, 1 */
outb(0x03, COM_PORT + MCR); /* Ready */
outb(0x00, COM_PORT + FCR); /* Disable FIFO */
inb(COM_PORT);
inb(COM_PORT);
return 0;
}