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-rw-r--r--arch/i686/include/gdt.h55
1 files changed, 0 insertions, 55 deletions
diff --git a/arch/i686/include/gdt.h b/arch/i686/include/gdt.h
deleted file mode 100644
index 9148c3d..0000000
--- a/arch/i686/include/gdt.h
+++ /dev/null
@@ -1,55 +0,0 @@
-#pragma once
-
-#include <stdbool.h>
-#include <stdint.h>
-
-enum Ring { Ring0 = 0x0, Ring1 = 0x1, Ring2 = 0x2, Ring3 = 0x3 };
-
-struct __attribute__((packed)) Access {
- bool accessed : 1; // if 0, is set by processor when accessed
- bool readwrite : 1; // code seg: read toggle; data seg: write toggle
- bool direction : 1; // code seg: conforming bit; data seg: direction bit
- bool executable : 1; // executable bit
- bool segment : 1; // true for code/data; false for gates/tss
- enum Ring privilege : 2; // descriptor privilege level
- bool present : 1; // true for every active segment
-};
-_Static_assert(sizeof(struct Access) == 1);
-
-static const struct Access null_access = {};
-static const struct Access ktext_access = {.readwrite = true, .executable = true, .segment = true, .present = true};
-static const struct Access kdata_access = {.readwrite = true, .segment = true, .present = true};
-
-// Segment Descriptor
-// A memory structure (part of a table) that tells the CPU the attributes of a given segment
-// |31| | | | | | |24|23|22|21|20|19| | |16|15| | | | | | | 8| 7| | | | | | | 0|
-// | base_31_24 | G|DB| | A| lim_19_16 | access | base_23_16 |
-// | base_15_0 | limit_15_0 |
-// |31| | | | | | | | | | | | | | |16|15| | | | | | | | | | | | | | | 0|
-// limit size of segment - 1, either in bytes or in 4KiB chunks (check flags)
-// base address of segment
-// access
-// flags defines the segment chunks and 16/32 bit
-struct __attribute__((packed)) SegmentDescriptor_t {
- uint16_t limit_15_0; // low bits of segment limit
- uint16_t base_15_0; // low bits of segment base address
- uint8_t base_23_16; // middle bits of segment base address
- uint8_t access; // access byte
- uint8_t limit_19_16 : 4; // high bits of segment limit
- // flags
- bool a : 1; // unused, available for software use
- bool rsv : 1; // reserved
- bool db : 1; // false => 16-bit seg; true => 32-bit seg
- bool granularity : 1; // limit scaled by 4k when set
- uint8_t base_31_24; // high bits of segment address
-};
-_Static_assert(sizeof(struct SegmentDescriptor_t) == 8);
-
-void SegmentDescriptor(struct SegmentDescriptor_t *self, unsigned base, unsigned limit, uint8_t access);
-
-void gdt_install();
-
-enum SegmentIndex {
- ktextDescriptor = 2 * sizeof(struct SegmentDescriptor_t),
- kdataDescriptor = 3 * sizeof(struct SegmentDescriptor_t),
-};