初始化IDT表

Author: avvCode

.vscode/settings.json

@@ -10,6 +10,7 @@
         "types.h": "c",
         "fcntl.h": "c",
         "_default_fcntl.h": "c",
-        "loader.h": "c"
+        "loader.h": "c",
+        "cpu_instr.h": "c"
     },
 }

source/comm/cpu_instr.h

@@ -55,6 +55,21 @@ static inline void write_cr0(uint32_t v) {
 	__asm__ __volatile__("mov %[v], %%cr0"::[v]"r"(v));
 }
 
+static inline void lidt(uint32_t start, uint32_t size) {
+	struct {
+		uint16_t limit;
+		uint16_t start15_0;
+		uint16_t start31_16;
+	} idt;
+
+	idt.start31_16 = start >> 16;
+	idt.start15_0 = start & 0xFFFF;
+	idt.limit = size - 1;
+
+	__asm__ __volatile__("lidt %[g]"::[g]"m"(idt));
+}
+
+
 static inline void far_jump(uint32_t selector, uint32_t offset) {
 	uint32_t addr[] = {offset, selector };
 	__asm__ __volatile__("ljmpl *(%[a])"::[a]"r"(addr));

source/kernel/cpu/cpu.c

@@ -19,6 +19,13 @@ void segment_desc_set(int selector, uint32_t base, uint32_t limit, uint16_t attr
 	desc->base31_24 = (base >> 24) & 0xff;
 }
 
+void gate_desc_set(gate_desc_t * desc, uint16_t selector, uint32_t offset, uint16_t attr){
+    desc->offset15_0 = offset & 0xFFFF;
+    desc->selector = selector;
+    desc->attr = attr;
+    desc->offset31_16 = (offset >> 16) & 0xFFFF;
+}
+
 void init_gdt (void) {
     for(int i = 0; i < GDT_TABLE_SIZE; i++){
         segment_desc_set( i << 3, 0 , 0 , 0);

source/kernel/cpu/irq.c

@@ -0,0 +1,15 @@
+#include "cpu/irq.h"
+#include "cpu/cpu.h"
+#include "comm/cpu_instr.h"
+
+#define IDE_TABLE_NR 128
+
+
+static gate_desc_t idt_table[IDE_TABLE_NR];
+
+void irq_init(void){
+    for(int i = 0; i < IDE_TABLE_NR; i++){
+        gate_desc_set(idt_table + i,0,0,0);
+    }
+    lidt((uint32_t) idt_table, sizeof(idt_table));
+}

source/kernel/include/cpu/cpu.h

@@ -13,6 +13,14 @@ typedef struct _segment_desc_t {
 	uint8_t base31_24;
 }segment_desc_t;
 
+
+typedef struct _gate_desc_t{
+	uint16_t offset15_0;
+	uint16_t selector;
+	uint16_t attr;
+	uint8_t offset31_16;
+}gate_desc_t;
+
 #pragma pack()
 
 #define SEG_G (1 << 15) 
@@ -32,5 +40,5 @@ typedef struct _segment_desc_t {
 
 void cpu_init(void);
 void segment_desc_set(int selector, uint32_t base, uint32_t limit, uint16_t attr);
-
+void gate_desc_set(gate_desc_t * desc, uint16_t selector, uint32_t offset, uint16_t attr);
 #endif

source/kernel/include/cpu/irq.h

@@ -0,0 +1,6 @@
+#ifndef IRQ_H
+#define IRQ_H
+
+void irq_init(void);
+
+#endif

source/kernel/init/init.c

@@ -4,6 +4,7 @@
  */
 #include "comm/boot_info.h"
 #include "cpu/cpu.h"
+#include "cpu/irq.h"
 
 
 /**
@@ -12,7 +13,7 @@
 void kernel_init (boot_info_t * boot_info) {
     //初始化GDT表
     cpu_init();
-    
+    irq_init();
 }
 
 void init_main(void){