arch_dbg_console.c

newos is new operation system

/*
** Copyright 2001, Travis Geiselbrecht. All rights reserved.
** Distributed under the terms of the NewOS License.
*/
/*
** Modified 2001/09/05 by Rob Judd<[e-mail]>
*/
#include <kernel/kernel.h>
#include <kernel/int.h>
#include <kernel/arch/cpu.h>
#include <kernel/arch/dbg_console.h>

#include <boot/stage2.h>

#include <string.h>

#if _SERIAL_DBG_PORT == 1
static const int serial_ioport_base = 0x3f8;
#elif _SERIAL_DBG_PORT == 2
static const int serial_ioport_base = 0x2f8;
#elif _SERIAL_DBG_PORT == 0xe9
#define BOCHS_E9_HACK 1
#else
#error _SERIAL_DBG_PORT set to unsupported com port
#endif

static const int dbg_baud_rate = 115200;

int arch_dbg_con_init(kernel_args *ka)
{
#if !BOCHS_E9_HACK
	short divisor = 115200 / dbg_baud_rate;

	out8(0x80, serial_ioport_base+3);	/* set up to load divisor latch	*/
	out8(divisor & 0xf, serial_ioport_base);		/* LSB */
	out8(divisor >> 8, serial_ioport_base+1);		/* MSB */
	out8(3, serial_ioport_base+3);		/* 8N1 */
#endif
	return NO_ERROR;
}

int arch_dbg_con_init2(kernel_args *ka)
{
	return NO_ERROR;
}

char arch_dbg_con_read(void)
{
#if BOCHS_E9_HACK
	return in8(0xe9);
#else
	while ((in8(serial_ioport_base+5) & 1) == 0)
		;
	return in8(serial_ioport_base);
#endif
}

static void _arch_dbg_con_putch(const char c)
{
#if BOCHS_E9_HACK
	out8(c, 0xe9);
#else

 	while ((in8(serial_ioport_base+5) & 0x20) == 0)
		;
	out8(c, serial_ioport_base);
 
#endif
}

char arch_dbg_con_putch(const char c)
{
	if (c == '\n') {
		_arch_dbg_con_putch('\r');
		_arch_dbg_con_putch('\n');
	} else if (c != '\r')
		_arch_dbg_con_putch(c);

	return c;
}

void arch_dbg_con_puts(const char *s)
{
	while(*s != '\0') {
		arch_dbg_con_putch(*s);
		s++;
	}
}

ssize_t arch_dbg_con_write(const void *buf, ssize_t len)
{
	const char *cbuf = (const char *)buf;
	ssize_t ret = len;

	while(len > 0) {
		arch_dbg_con_putch(*cbuf);
		cbuf++;
		len--;
	}
	return ret;
}