metalsvm/arch/x86/include/asm/gdt.h
stefan 45219bce2e - huge commit
- enable the paging support
- redesign of the APIC code

TODO:
- Currently, we are not able to start user-level applications.
- The RTL8139 driver does not longer work. Perhaps, a bug in the output function.
- The APIC codes doesn't work on all systems. Therefore, the code is currently disabled.



git-svn-id: http://svn.lfbs.rwth-aachen.de/svn/scc/trunk/MetalSVM@326 315a16e6-25f9-4109-90ae-ca3045a26c18
2010-12-10 06:16:58 +00:00

70 lines
1.7 KiB
C

/*
* Copyright 2010 Stefan Lankes, Chair for Operating Systems,
* RWTH Aachen University
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of MetalSVM.
*/
#ifndef __ARCH_GDT_H__
#define __ARCH_GDT_H__
#include <metalsvm/stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
#define GDT_FLAG_DATASEG 0x02
#define GDT_FLAG_CODESEG 0x0a
#define GDT_FLAG_TSS 0x09
#define GDT_FLAG_TSS_BUSY 0x02
#define GDT_FLAG_SEGMENT 0x10
#define GDT_FLAG_RING0 0x00
#define GDT_FLAG_RING1 0x20
#define GDT_FLAG_RING2 0x40
#define GDT_FLAG_RING3 0x60
#define GDT_FLAG_PRESENT 0x80
#define GDT_FLAG_4K_GRAN 0x80
#define GDT_FLAG_32_BIT 0x40
/* Defines a GDT entry */
typedef struct {
unsigned short limit_low;
unsigned short base_low;
unsigned char base_middle;
unsigned char access;
unsigned char granularity;
unsigned char base_high;
} __attribute__ ((packed)) gdt_entry_t;
typedef struct {
unsigned short limit;
unsigned int base;
} __attribute__ ((packed)) gdt_ptr_t;
#define GDT_ENTRIES (5+MAX_TASKS)
#if GDT_ENTRIES > 8192
#error Too many GDT entries!
#endif
void gdt_install(void);
#ifdef __cplusplus
}
#endif
#endif