51 lines
2.4 KiB
C
51 lines
2.4 KiB
C
|
#ifndef _GDT_EC_H
|
||
|
|
#define _GDT_EC_H
|
||
|
|
|
||
|
|
#include <types.h>
|
||
|
|
|
||
|
|
// Each define here is for a specific flag in the descriptor.
|
||
|
|
// Refer to the intel documentation for a description of what each one does.
|
||
|
|
#define SEG_DESCTYPE(x) ((x) << 0x04) // Descriptor type (0 for system, 1 for code/data)
|
||
|
|
#define SEG_PRES(x) ((x) << 0x07) // Present
|
||
|
|
#define SEG_SAVL(x) ((x) << 0x0C) // Available for system use
|
||
|
|
#define SEG_LONG(x) ((x) << 0x0D) // Long mode
|
||
|
|
#define SEG_SIZE(x) ((x) << 0x0E) // Size (0 for 16-bit, 1 for 32)
|
||
|
|
#define SEG_GRAN(x) ((x) << 0x0F) // Granularity (0 for 1B - 1MB, 1 for 4KB - 4GB)
|
||
|
|
#define SEG_PRIV(x) (((x) & 0x03) << 0x05) // Set privilege level (0 - 3)
|
||
|
|
|
||
|
|
#define SEG_DATA_RD 0x00 // Read-Only
|
||
|
|
#define SEG_DATA_RDA 0x01 // Read-Only, accessed
|
||
|
|
#define SEG_DATA_RDWR 0x02 // Read/Write
|
||
|
|
#define SEG_DATA_RDWRA 0x03 // Read/Write, accessed
|
||
|
|
#define SEG_DATA_RDEXPD 0x04 // Read-Only, expand-down
|
||
|
|
#define SEG_DATA_RDEXPDA 0x05 // Read-Only, expand-down, accessed
|
||
|
|
#define SEG_DATA_RDWREXPD 0x06 // Read/Write, expand-down
|
||
|
|
#define SEG_DATA_RDWREXPDA 0x07 // Read/Write, expand-down, accessed
|
||
|
|
#define SEG_CODE_EX 0x08 // Execute-Only
|
||
|
|
#define SEG_CODE_EXA 0x09 // Execute-Only, accessed
|
||
|
|
#define SEG_CODE_EXRD 0x0A // Execute/Read
|
||
|
|
#define SEG_CODE_EXRDA 0x0B // Execute/Read, accessed
|
||
|
|
#define SEG_CODE_EXC 0x0C // Execute-Only, conforming
|
||
|
|
#define SEG_CODE_EXCA 0x0D // Execute-Only, conforming, accessed
|
||
|
|
#define SEG_CODE_EXRDC 0x0E // Execute/Read, conforming
|
||
|
|
#define SEG_CODE_EXRDCA 0x0F // Execute/Read, conforming, accessed
|
||
|
|
|
||
|
|
#define GDT_CODE_PL0 SEG_DESCTYPE(1) | SEG_PRES(1) | SEG_SAVL(0) | \
|
||
|
|
SEG_LONG(0) | SEG_SIZE(1) | SEG_GRAN(1) | \
|
||
|
|
SEG_PRIV(0) | SEG_CODE_EXRD
|
||
|
|
|
||
|
|
#define GDT_DATA_PL0 SEG_DESCTYPE(1) | SEG_PRES(1) | SEG_SAVL(0) | \
|
||
|
|
SEG_LONG(0) | SEG_SIZE(1) | SEG_GRAN(1) | \
|
||
|
|
SEG_PRIV(0) | SEG_DATA_RDWR
|
||
|
|
|
||
|
|
#define GDT_CODE_PL3 SEG_DESCTYPE(1) | SEG_PRES(1) | SEG_SAVL(0) | \
|
||
|
|
SEG_LONG(0) | SEG_SIZE(1) | SEG_GRAN(1) | \
|
||
|
|
SEG_PRIV(3) | SEG_CODE_EXRD
|
||
|
|
|
||
|
|
#define GDT_DATA_PL3 SEG_DESCTYPE(1) | SEG_PRES(1) | SEG_SAVL(0) | \
|
||
|
|
SEG_LONG(0) | SEG_SIZE(1) | SEG_GRAN(1) | \
|
||
|
|
SEG_PRIV(3) | SEG_DATA_RDWR
|
||
|
|
|
||
|
|
|
||
|
|
#endif
|