53 lines
1.2 KiB
C++
53 lines
1.2 KiB
C++
#include "gdt.hpp"
|
|
#include "../Helpers/types.hpp"
|
|
#include "../Helpers/memory.hpp"
|
|
|
|
|
|
Gdt::Gdt(){
|
|
|
|
//Init conventional segment
|
|
this->initGdtDesc(0x0,0x0,0x0,0x0, &m_Descriptors[0]);
|
|
|
|
//Init code segment
|
|
this->initGdtDesc(0x0,0xFFFFF,0x9A,0x0D, &m_Descriptors[1]);
|
|
|
|
//Init data segment
|
|
this->initGdtDesc(0x0,0xFFFFF,0x92,0x0D, &m_Descriptors[2]);
|
|
|
|
//Init stack segment
|
|
this->initGdtDesc(0x00B00000,0x00000500,0x96,0x0D, &m_Descriptors[3]);
|
|
|
|
|
|
//Init GDT Pointer
|
|
this->m_Pointer.size=4*sizeof(this->m_Descriptors);
|
|
this->m_Pointer.segment=0x00007E00;
|
|
|
|
|
|
}
|
|
|
|
Gdt::~Gdt(){
|
|
|
|
}
|
|
|
|
void Gdt::initGdtDesc(u32 base, u32 limit, u8 access, u8 flags, gdtDescriptorStruct *Descriptor){
|
|
Descriptor->limit1 = limit & 0xFFFF;
|
|
Descriptor->base1 = base & 0xFFFF;
|
|
Descriptor->base2 = (base & 0xFF0000) >> 16;
|
|
Descriptor->access = access;
|
|
Descriptor->limit2 = (limit & 0xF0000 ) >> 16;
|
|
Descriptor->flags = flags & 0xFF;
|
|
Descriptor->base3 = (base & 0xFF000000) >> 24;
|
|
}
|
|
|
|
void Gdt::loadGdt(){
|
|
int *gdtAdress=(int *)&m_Pointer;
|
|
//Copy Gdt into memory and init registers
|
|
memcpy((u32)m_Descriptors, (u32)m_Pointer.segment, (u32)m_Pointer.size);
|
|
|
|
__asm__("lgdtl (%0);"
|
|
:
|
|
:"r"(gdtAdress)
|
|
);
|
|
}
|
|
|
|
|