x86.h

FritzOS - 简单的C++开发OS的实例// 英文

/* x86.h : FritzOS x86 Header File For The FritzOS C++ Kernel
   Copyright (C) 2002 Tom Fritz

 * This program is a part of the FritzOS kernel, and may be freely
 * copied under the terms of the GNU General Public License (GPL),
 * version 2, or at your option any later version.

   For more info, look at the COPYING file.
*/

/*
	This file is for using the x86 instructions in C
*/

// defines:

#ifndef X86_H
#define X86_H

// If someone wants to use sti or cli in a more understanding way, define enable_ints and disable_ints
#define enable_ints sti
#define disable_ints cli

// voids:

// inb: get a byte from the selected port
__inline__ unsigned inportb(unsigned port);

// outb: send the selected byte to the selected port
__inline__ void outportb(unsigned port, unsigned val);

// Enable Interrupts:
__inline__ void sti();

// Disable Interrupts:
__inline__ void cli();

// A reboot function for rebooting the computer:
void reboot();

// data:
int checkints;		// for checking if interrupts are disabled or enabled

//***********************************************************************************************************
//

__inline__ unsigned inportb(unsigned port)
{
	unsigned ret_val;

	__asm__ __volatile__("inb %w1,%b0"
		: "=a"(ret_val)
		: "d"(port));

	return ret_val;
}

//***********************************************************************************************************
//

__inline__ void outportb(unsigned port, unsigned val)
{
	__asm__ __volatile__("outb %b0,%w1"
		:
		: "a"(val), "d"(port));
}

//***********************************************************************************************************
//

void reboot()
{
	int temp;		// A temporary int for storing keyboard info. The keyboard can be use to
				//  reboot the PC

	// Get ready for reboot...flush the keyboard controller
        do
        {
                temp = inportb( 0x64 );

                if ( temp & 1 )
                        inportb( 0x60 );
        }
	while ( temp & 2 );

        // Reboot the computer...
        outportb(0x64, 0xFE);

	// If this didn't reboot the computer...let the code that calles this handle that.
}

//***********************************************************************************************************
//

__inline__ void sti()
{
	__asm__ __volatile__( "sti" );	// Enable ints

	// Set checkints to 1 - on
	checkints = 1;
}

//***********************************************************************************************************
//

__inline__ void cli()
{
	__asm__ __volatile__( "cli" );	// Disable ints

	// Set checkints to 0 - off
	checkints = 0;
}

#endif

// end of x86.h