limine/common/sys/gdt.s2.c
2022-09-02 02:29:12 +02:00

86 lines
1.7 KiB
C

#if defined (__x86_64__) || defined (__i386__)
#include <stdint.h>
#include <sys/gdt.h>
#include <mm/pmm.h>
#include <lib/libc.h>
static struct gdt_desc gdt_descs[] = {
{0},
{
.limit = 0xffff,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10011010,
.granularity = 0b00000000,
.base_hi = 0x00
},
{
.limit = 0xffff,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10010010,
.granularity = 0b00000000,
.base_hi = 0x00
},
{
.limit = 0xffff,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10011010,
.granularity = 0b11001111,
.base_hi = 0x00
},
{
.limit = 0xffff,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10010010,
.granularity = 0b11001111,
.base_hi = 0x00
},
{
.limit = 0x0000,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10011010,
.granularity = 0b00100000,
.base_hi = 0x00
},
{
.limit = 0x0000,
.base_low = 0x0000,
.base_mid = 0x00,
.access = 0b10010010,
.granularity = 0b00000000,
.base_hi = 0x00
}
};
#if defined (BIOS)
__attribute__((section(".realmode")))
#endif
struct gdtr gdt = {
sizeof(gdt_descs) - 1,
(uintptr_t)gdt_descs,
#if defined (__i386__)
0
#endif
};
#if defined (UEFI)
void init_gdt(void) {
struct gdt_desc *gdt_copy = ext_mem_alloc(sizeof(gdt_descs));
memcpy(gdt_copy, gdt_descs, sizeof(gdt_descs));
gdt.ptr = (uintptr_t)gdt_copy;
}
#endif
#endif