/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                            i8259.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                                                    Forrest Yu, 2005
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/


#include "type.h"
#include "const.h"
#include "protect.h"
#include "proc.h"
#include "global.h"
#include "proto.h"
#include "x86.h"
#include "stdio.h"


/*======================================================================*
                            init_8259A
 *======================================================================*/
void init_8259A()
{
	outb(INT_M_CTL,	0x11);			// Master 8259, ICW1.
	outb(INT_S_CTL,	0x11);			// Slave  8259, ICW1.
	outb(INT_M_CTLMASK,	INT_VECTOR_IRQ0);	// Master 8259, ICW2. 设置 '主8259' 的中断入口地址为 0x20.
	outb(INT_S_CTLMASK,	INT_VECTOR_IRQ8);	// Slave  8259, ICW2. 设置 '从8259' 的中断入口地址为 0x28
	outb(INT_M_CTLMASK,	0x4);			// Master 8259, ICW3. IR2 对应 '从8259'.
	outb(INT_S_CTLMASK,	0x2);			// Slave  8259, ICW3. 对应 '主8259' 的 IR2.
	outb(INT_M_CTLMASK,	0x1);			// Master 8259, ICW4.
	outb(INT_S_CTLMASK,	0x1);			// Slave  8259, ICW4.

	outb(INT_M_CTLMASK,	0xFF);	// Master 8259, OCW1. 
	outb(INT_S_CTLMASK,	0xFF);	// Slave  8259, OCW1.

	int i;
	for (i = 0; i < NR_IRQ; i++) {
		irq_table[i] = spurious_irq;
	}
}

void disable_irq(int irq)
{
	u8 mask = 1 << (irq % 8);
        if (irq < 8)
                outb(INT_M_CTLMASK, inb(INT_M_CTLMASK) | mask);
        else
                outb(INT_S_CTLMASK, inb(INT_S_CTLMASK) | mask);
}

void enable_irq(int irq)
{
	u8 mask = 1 << (irq % 8);
        if (irq < 8)
                outb(INT_M_CTLMASK, inb(INT_M_CTLMASK) & ~mask);
        else
                outb(INT_S_CTLMASK, inb(INT_S_CTLMASK) & ~mask);
}

/*======================================================================*
                           spurious_irq
 *======================================================================*/
void spurious_irq(int irq)
{
	kprintf("spurious_irq: %d\n", irq);
}

/*======================================================================*
                           put_irq_handler
 *======================================================================*/
void put_irq_handler(int irq, irq_handler handler)
{
	disable_irq(irq);
	irq_table[irq] = handler;
}