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/*
 *                               POK header
 * 
 * The following file is a part of the POK project. Any modification should
 * made according to the POK licence. You CANNOT use this file or a part of
 * this file is this part of a file for your own project
 *
 * For more information on the POK licence, please see our LICENCE FILE
 *
 * Please follow the coding guidelines described in doc/CODING_GUIDELINES
 *
 *                                      Copyright (c) 2007-2009 POK team 
 *
 * Created by julien on Thu Jan 15 23:34:13 2009 
 */


#ifndef __POK_X86_GDT_H__
#define __POK_X86_GDT_H__

#include <types.h>

typedef enum e_gdte_type
{
  GDTE_CODE = 0xB,
  GDTE_DATA = 0x3,
  GDTE_TSS = 0x9
} e_gdte_type;

typedef struct
{
   uint32_t     limit_low:16;
   uint32_t     base_low:24 __attribute__ ((packed));
   uint32_t     type:4;
   uint32_t     s:1;
   uint32_t     dpl:2;
   uint32_t     present:1;
   uint32_t     limit_high:4;
   uint32_t     available:2;
   uint32_t     op_size:1;
   uint32_t     granularity:1;
   uint32_t     base_high:8;
} __attribute__((packed)) gdt_entry_t;

#define GDT_CORE_CODE_SEGMENT   1
#define GDT_CORE_DATA_SEGMENT   2
#define GDT_TSS_SEGMENT         3

#define GDT_PARTITION_CODE_SEGMENT(partition_id)        (4 + 2 * partition_id)
#define GDT_PARTITION_DATA_SEGMENT(partition_id)        (4 + 2 * partition_id + 1)

#define GDT_BUILD_SELECTOR(seg, local, rpl)     \
   ((seg << 3) | ((local & 0x1) << 2) | (rpl & 0x3))

pok_ret_t   pok_gdt_init();
int         pok_tss_init();

void        tss_set_esp0(uint32_t esp0);

void        gdt_set_segment (uint16_t index,
                             uint32_t base_address,
                             uint32_t limit,
                             e_gdte_type t,
                             int dpl);

void gdt_set_system (uint16_t index,
                     uint32_t base_address,
                     uint32_t limit,
                     e_gdte_type t,
                     int dpl);

void gdt_enable (uint16_t index);
void gdt_disable (uint16_t index);

/*
 * DEPRECATED
uint32_t        gdt_segment_base(uint16_t idx);
*/

#endif /* !__POK_X86_GDT_H__ */