Improved build system
Added new entries to .gitignore Moved away from source directory as central spot for all source code
This commit is contained in:
46
kernel/memory/gdt/gdtc.cpp
Normal file
46
kernel/memory/gdt/gdtc.cpp
Normal file
@ -0,0 +1,46 @@
|
||||
#include "gdtc.h"
|
||||
#include "../../terminal/kterm.h"
|
||||
|
||||
|
||||
SegmentDescriptor GlobalDescriptorTable[6];
|
||||
GlobalDescriptorTableDescriptor gdtDescriptor;
|
||||
|
||||
|
||||
void add_descriptor(int which , unsigned long base, unsigned long limit, unsigned char access, unsigned char granularity ){
|
||||
GlobalDescriptorTable[which].base_low = (base & 0xFFFF );
|
||||
GlobalDescriptorTable[which].base_middle = (base >> 6) & 0xFF;
|
||||
GlobalDescriptorTable[which].base_high = (base >> 24) & 0xFF;
|
||||
|
||||
GlobalDescriptorTable[which].limit_low = (limit & 0xFFFF);
|
||||
GlobalDescriptorTable[which].granularity = ((limit >> 16) & 0x0F);
|
||||
|
||||
GlobalDescriptorTable[which].granularity |= (granularity & 0xF0);
|
||||
GlobalDescriptorTable[which].access = access;
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
void initGDT(){
|
||||
|
||||
// NULL segment
|
||||
add_descriptor(NULL_SEGMENT, 0,0,0,0);
|
||||
|
||||
// Kernel Code Segment
|
||||
add_descriptor(KERNEL_CODE_SEGMENT, 0, 0xFFFFFFFF, 0x9A, 0xCF);
|
||||
|
||||
// Kernel Data Segment
|
||||
add_descriptor(KERNEL_DATA_SEGMENT, 0, 0xFFFFFFFF, 0x92, 0xCF);
|
||||
|
||||
// User Code Segment
|
||||
add_descriptor(USER_CODE_SEGMENT, 0, 0xFFFFFFFF, 0xFA, 0xCF);
|
||||
|
||||
// User Data Segement
|
||||
add_descriptor(USER_DATA_SEGMENT, 0, 0xFFFFFFFF, 0xF2, 0xCF);
|
||||
|
||||
// init Gdt Descriptor
|
||||
gdtDescriptor.limit = ((sizeof(SegmentDescriptor ) * 6 ) - 1);
|
||||
gdtDescriptor.base = (unsigned int) (&GlobalDescriptorTable);
|
||||
|
||||
}
|
||||
Reference in New Issue
Block a user