Files
42_KFS/src/multiboot.c

70 lines
2.3 KiB
C

#include <stddef.h>
#include <stdint.h>
#include "commands.h"
#include "debug.h"
#include "kpanic.h"
#include "memory.h"
#include "multiboot.h"
#include "utils.h"
#include "vbe.h"
uint32_t multiboot_page_table[1024] __attribute__((aligned(PAGE_SIZE)));
uint32_t vbe_page_table[1024] __attribute__((aligned(PAGE_SIZE)));
multiboot_memory_map_t *mmap_addr;
multiboot_uint32_t mmap_length;
static void init_mmap(multiboot_info_t *mbd_virt, size_t *pt_index)
{
// Index mbd->mmap_addr pointers
uint32_t i = 0;
for (; i < mbd_virt->mmap_length; i++)
multiboot_page_table[i + *pt_index] =
((mbd_virt->mmap_addr + i * PAGE_SIZE) & PAGE_MASK) |
INIT_FLAGS;
mmap_addr = (multiboot_memory_map_t *)(GET_PAGE_ADDR(1023, *pt_index) +
(uint32_t)mbd_virt->mmap_addr %
PAGE_SIZE);
mmap_length = mbd_virt->mmap_length / sizeof(multiboot_memory_map_t);
*pt_index += i;
}
static void init_vbe(multiboot_info_t *mbd_virt)
{
const uint32_t framebuffer_size =
mbd_virt->framebuffer_height * mbd_virt->framebuffer_pitch;
for (uint32_t i = 0; i < CEIL(framebuffer_size, PAGE_SIZE); i++) {
vbe_page_table[i % 1024] =
((mbd_virt->framebuffer_addr + i * PAGE_SIZE) & PAGE_MASK) |
INIT_FLAGS;
}
kernel_pd[800] = ((uint32_t)vbe_page_table - HEAP_END) | 0x03;
display.buff = (uint32_t *)GET_PAGE_ADDR(800, 0) +
(mbd_virt->framebuffer_addr % PAGE_SIZE);
display.height = mbd_virt->framebuffer_height;
display.width = mbd_virt->framebuffer_width;
display.pitch = mbd_virt->framebuffer_pitch;
display.bpp = mbd_virt->framebuffer_bpp;
}
void init_multiboot(multiboot_info_t *mbd, uint32_t magic)
{
if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
kpanic("invalid magic number! (git good skill issue)");
init_page_table(multiboot_page_table, 0);
kernel_pd[1023] = ((uint32_t)multiboot_page_table - HEAP_END) | 0x03;
size_t pt_index = CEIL(
(uint32_t)mbd % PAGE_SIZE + sizeof(multiboot_info_t), PAGE_SIZE);
// Index multiboot_info_t struct
for (uint32_t i = 0; i < pt_index; i++)
multiboot_page_table[i] =
(((uint32_t)mbd + PAGE_SIZE * i) & PAGE_MASK) | INIT_FLAGS;
multiboot_info_t *mbd_virt =
(multiboot_info_t *)(GET_PAGE_ADDR(1023, 0) +
(uint32_t)mbd % PAGE_SIZE);
init_mmap(mbd_virt, &pt_index);
init_vbe(mbd_virt);
}