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/*
* (C) Copyright 2002
* Daniel Engström, Omicron Ceti AB, daniel@omicron.se.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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 (at your option) 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., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/interrupt.h>
struct idt_entry {
u16 base_low;
u16 selector;
u8 res;
u8 access;
u16 base_high;
} __attribute__ ((packed));
struct idt_entry idt[256];
asm (".globl irq_return\n"
"irq_return:\n"
" addl $4, %esp\n"
" popa\n"
" iret\n");
void __attribute__ ((regparm(0))) default_isr(void);
asm ("default_isr: iret\n");
asm ("idt_ptr:\n"
".word 0x800\n" /* size of the table 8*256 bytes */
".long idt\n" /* offset */
".word 0x18\n");/* data segment */
void set_vector(u8 intnum, void *routine)
{
idt[intnum].base_high = (u16)((u32)(routine + gd->reloc_off) >> 16);
idt[intnum].base_low = (u16)((u32)(routine + gd->reloc_off) & 0xffff);
}
int cpu_init_interrupts(void)
{
int i;
/* Just in case... */
disable_interrupts();
/* Setup the IDT */
for (i=0;i<256;i++) {
idt[i].access = 0x8e;
idt[i].res = 0;
idt[i].selector = 0x10;
set_vector(i, default_isr);
}
asm ("cs lidt idt_ptr\n");
/* It is now safe to enable interrupts */
enable_interrupts();
return 0;
}
void enable_interrupts(void)
{
asm("sti\n");
}
int disable_interrupts(void)
{
long flags;
asm volatile ("pushfl ; popl %0 ; cli\n" : "=g" (flags) : );
return (flags&0x200); /* IE flags is bit 9 */
}
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