mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-19 08:28:51 +09:00
97 lines
2.1 KiB
C
97 lines
2.1 KiB
C
/*
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* (C) Copyright 2002
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* Daniel Engström, Omicron Ceti AB, daniel@omicron.se.
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*
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* See file CREDITS for list of people who contributed to this
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* project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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*/
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#include <common.h>
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#include <asm/interrupt.h>
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struct idt_entry {
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u16 base_low;
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u16 selector;
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u8 res;
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u8 access;
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u16 base_high;
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} __attribute__ ((packed));
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struct idt_entry idt[256];
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asm (".globl irq_return\n"
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"irq_return:\n"
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" addl $4, %esp\n"
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" popa\n"
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" iret\n");
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void __attribute__ ((regparm(0))) default_isr(void);
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asm ("default_isr: iret\n");
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asm ("idt_ptr:\n"
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".word 0x800\n" /* size of the table 8*256 bytes */
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".long idt\n" /* offset */
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".word 0x18\n");/* data segment */
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void set_vector(u8 intnum, void *routine)
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{
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idt[intnum].base_high = (u16)((u32)(routine + gd->reloc_off) >> 16);
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idt[intnum].base_low = (u16)((u32)(routine + gd->reloc_off) & 0xffff);
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}
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int cpu_init_interrupts(void)
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{
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int i;
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/* Just in case... */
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disable_interrupts();
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/* Setup the IDT */
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for (i=0;i<256;i++) {
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idt[i].access = 0x8e;
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idt[i].res = 0;
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idt[i].selector = 0x10;
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set_vector(i, default_isr);
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}
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asm ("cs lidt idt_ptr\n");
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/* It is now safe to enable interrupts */
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enable_interrupts();
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return 0;
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}
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void enable_interrupts(void)
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{
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asm("sti\n");
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}
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int disable_interrupts(void)
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{
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long flags;
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asm volatile ("pushfl ; popl %0 ; cli\n" : "=g" (flags) : );
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return (flags&0x200); /* IE flags is bit 9 */
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}
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