54 lines
1.3 KiB
C
54 lines
1.3 KiB
C
/* vim: tabstop=4 shiftwidth=4 noexpandtab
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* This file is part of ToaruOS and is released under the terms
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* of the NCSA / University of Illinois License - see LICENSE.md
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* Copyright (C) 2011-2018 K. Lange
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* Copyright (C) 2015 Dale Weiler
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*
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* Interrupt Descriptor Tables
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*
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*/
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#include <kernel/system.h>
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#include <kernel/logging.h>
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typedef struct {
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uint16_t base_low;
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uint16_t sel;
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uint8_t zero;
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uint8_t flags;
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uint16_t base_high;
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} __attribute__((packed)) idt_entry_t;
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typedef struct {
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uint16_t limit;
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uintptr_t base;
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} __attribute__((packed)) idt_pointer_t;
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/* In the future we may need to put a lock on the access of this */
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static struct {
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idt_entry_t entries[256];
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idt_pointer_t pointer;
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} idt __attribute__((used));
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#define ENTRY(X) (idt.entries[(X)])
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typedef void (*idt_gate_t)(void);
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extern void idt_load(uintptr_t);
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void idt_set_gate(uint8_t num, idt_gate_t base, uint16_t sel, uint8_t flags) {
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ENTRY(num).base_low = ((uintptr_t)base & 0xFFFF);
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ENTRY(num).base_high = ((uintptr_t)base >> 16) & 0xFFFF;
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ENTRY(num).sel = sel;
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ENTRY(num).zero = 0;
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ENTRY(num).flags = flags | 0x60;
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}
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void idt_install(void) {
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idt_pointer_t * idtp = &idt.pointer;
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idtp->limit = sizeof idt.entries - 1;
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idtp->base = (uintptr_t)&ENTRY(0);
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memset(&ENTRY(0), 0, sizeof idt.entries);
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idt_load((uintptr_t)idtp);
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}
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