46 lines
888 B
C
46 lines
888 B
C
#include <stdint.h>
|
|
#include <stddef.h>
|
|
#include <sys/e820.h>
|
|
#include <lib/real.h>
|
|
#include <lib/blib.h>
|
|
#include <lib/print.h>
|
|
#include <mm/pmm.h>
|
|
|
|
struct e820_entry_t *e820_map = NULL;
|
|
size_t e820_entries;
|
|
|
|
void init_e820(void) {
|
|
struct rm_regs r = {0};
|
|
|
|
load_up:
|
|
// Figure out the number of entries
|
|
for (size_t i = 0; ; i++) {
|
|
struct e820_entry_t entry;
|
|
|
|
r.eax = 0xe820;
|
|
r.ecx = 24;
|
|
r.edx = 0x534d4150;
|
|
r.edi = (uint32_t)&entry;
|
|
rm_int(0x15, &r, &r);
|
|
|
|
if (r.eflags & EFLAGS_CF) {
|
|
e820_entries = i;
|
|
break;
|
|
}
|
|
|
|
if (e820_map)
|
|
e820_map[i] = entry;
|
|
|
|
if (!r.ebx) {
|
|
e820_entries = ++i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (e820_map)
|
|
return;
|
|
|
|
e820_map = conv_mem_alloc(sizeof(struct e820_entry_t) * e820_entries);
|
|
goto load_up;
|
|
}
|