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-rw-r--r--cpu/gdt.h76
1 files changed, 0 insertions, 76 deletions
diff --git a/cpu/gdt.h b/cpu/gdt.h
deleted file mode 100644
index a490dea..0000000
--- a/cpu/gdt.h
+++ /dev/null
@@ -1,76 +0,0 @@
-#ifndef GDT_H
-#define GDT_H
-#include <stdint.h>
-#include <string.h>
-
-#define GDT_ENTRY_SIZE 0x8
-#define GDT_NULL_SEGMENT 0x0
-#define GDT_KERNEL_CODE_SEGMENT 0x1
-#define GDT_KERNEL_DATA_SEGMENT 0x2
-#define GDT_USERMODE_CODE_SEGMENT 0x3
-#define GDT_USERMODE_DATA_SEGMENT 0x4
-#define GDT_TSS_SEGMENT 0x5
-
-struct GDT_Entry
-{
- uint16_t limit_low;
- uint32_t base_low : 24;
- uint32_t accessed : 1;
- uint32_t read_write : 1; // readable for code, writable for data
- uint32_t conforming_expand_down : 1; // conforming for code, expand down for data
- uint32_t code : 1; // 1 for code, 0 for data
- uint32_t code_data_segment : 1; // should be 1 for everything but TSS and LDT
- uint32_t DPL : 2; // privilege level
- uint32_t present : 1;
- uint32_t limit_high : 4;
- uint32_t available : 1; // only used in software; has no effect on hardware
- uint32_t long_mode : 1;
- uint32_t big : 1; // 32-bit opcodes for code, uint32_t stack for data
- uint32_t gran : 1; // 1 to use 4k page addressing, 0 for byte addressing
- uint8_t base_high;
-}__attribute__((packed));
-
-typedef struct GDT_Pointer
-{
- uint16_t size;
- uint32_t offset;
-}__attribute__((packed)) GDT_Pointer;
-
-struct tss_entry_struct
-{
- uint32_t prev_tss; // The previous TSS - with hardware task switching these form a kind of backward linked list.
- uint32_t esp0; // The stack pointer to load when changing to kernel mode.
- uint32_t ss0; // The stack segment to load when changing to kernel mode.
- // Everything below here is unused.
- uint32_t esp1; // esp and ss 1 and 2 would be used when switching to rings 1 or 2.
- uint32_t ss1;
- uint32_t esp2;
- uint32_t ss2;
- uint32_t cr3;
- uint32_t eip;
- uint32_t eflags;
- uint32_t eax;
- uint32_t ecx;
- uint32_t edx;
- uint32_t ebx;
- uint32_t esp;
- uint32_t ebp;
- uint32_t esi;
- uint32_t edi;
- uint32_t es;
- uint32_t cs;
- uint32_t ss;
- uint32_t ds;
- uint32_t fs;
- uint32_t gs;
- uint32_t ldt;
- uint16_t trap;
- uint16_t iomap_base;
-} __attribute__((packed));
-
-void gdt_init();
-
-uint8_t gen_access_byte(uint8_t priv, uint8_t s, uint8_t ex, uint8_t dc, uint8_t rw);
-uint64_t gen_gdt_entry(uint32_t base, uint32_t limit, uint8_t access_byte, uint8_t flag);
-uint8_t gen_flag(uint8_t gr, uint8_t sz);
-#endif