68 lines
1.9 KiB
C++
68 lines
1.9 KiB
C++
#include <idt.h>
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#include <common.h>
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#include <string_utils.h>
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#include <pic.h>
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#include <serial.h>
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// Defined in isr.S — 256 ISR stubs
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extern "C" void* isr_stub_table[256];
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static idt_entry g_idt[256];
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static idt_ptr g_idt_ptr;
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static isr_handler_t g_handlers[256] = {0};
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void idt_set_handler(UINT8 vector, isr_handler_t handler) {
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g_handlers[vector] = handler;
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}
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// Called from isr.S common handler
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extern "C" void isr_dispatch(trap_frame* frame) {
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UINT8 vector = (UINT8)frame->vector;
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if (g_handlers[vector]) {
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g_handlers[vector](frame);
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} else if (vector < 32) {
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serial_write("IDT: unhandled exception #");
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serial_write_hex(vector);
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serial_write(" error=");
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serial_write_hex(frame->error_code);
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serial_write("\n");
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while (1) ASM("hlt");
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}
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}
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// IDT helpers (defined in idt_helpers.S)
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extern "C" void idt_load(UINT64 base, UINT16 limit);
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static void idt_set_entry(UINT8 vector, UINT64 handler_addr) {
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g_idt[vector].offset_low = handler_addr & 0xFFFF;
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g_idt[vector].selector = 0x08; // kernel code segment
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g_idt[vector].ist = 0;
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g_idt[vector].type_attr = 0x8E; // present, DPL=0, 64-bit interrupt gate
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g_idt[vector].offset_mid = (handler_addr >> 16) & 0xFFFF;
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g_idt[vector].offset_high = (handler_addr >> 32) & 0xFFFFFFFF;
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g_idt[vector].reserved = 0;
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}
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void idt_init(void) {
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serial_write("IDT: initializing 256 entries\n");
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// Clear IDT
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for (SSINT32 i = 0; i < 256; i++) {
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g_idt[i] = {0};
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g_handlers[i] = NULL;
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}
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// Install all 256 ISR stubs
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for (SSINT32 i = 0; i < 256; i++) {
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idt_set_entry(i, (UINT64)isr_stub_table[i]);
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}
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// Load IDT
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g_idt_ptr.limit = sizeof(g_idt) - 1;
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g_idt_ptr.base = (UINT64)&g_idt[0];
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idt_load(g_idt_ptr.base, g_idt_ptr.limit);
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serial_write("IDT: loaded\n");
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}
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