blob: 8a7d0d6cb912f0d5ba446b9e8c971ebf009a6379 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
#include <types.h>
#include <multiboot2.h>
#include <graphics.h>
#include <paging.h>
#include <libk/serial_stdio.h>
#include <libk/string.h>
#include <libk/list.h>
#include <heap.h>
#include <kernel_vma.h>
/* https://www.gnu.org/software/grub/manual/multiboot2/html_node/Boot-information-format.html */
mb2_tag_module *ext2_module;
mmap_t mmap;
void init_fb(mb2_tag_fb *tag_fb)
{
main_fb.addr = tag_fb->framebuffer_addr;
main_fb.width = tag_fb->framebuffer_width;
main_fb.height = tag_fb->framebuffer_height;
main_fb.pitch = tag_fb->framebuffer_pitch;
main_fb.bpp = tag_fb->framebuffer_bpp;
main_fb.char_col = WHITE;
main_fb.bg_col = BLACK;
// identity map framebuffer address
map_addr(main_fb.addr, main_fb.addr, FLAG_PRESENT | FLAG_WRITABLE);
map_addr(main_fb.addr + PAGE_SIZE, main_fb.addr + PAGE_SIZE,
FLAG_PRESENT | FLAG_WRITABLE);
}
void init_mmap(mb2_tag_mmap *tag_mmap)
{
INIT_LIST(mmap.list)
// get data and store it into list
for (size_t i = sizeof(mb2_tag_mmap); i < tag_mmap->size;
i += sizeof(mb2_tag_mmap_entry)) {
mmap_t *curr_mmap_entry = (mmap_t *)kalloc(sizeof(mmap_t));
memcpy(&curr_mmap_entry->mmap_entry, (char *)tag_mmap + i,
sizeof(mb2_tag_mmap_entry));
add_to_list(&curr_mmap_entry->list, &mmap.list, mmap.list.next);
}
}
void init_module(mb2_tag_module *tag_module)
{
// name is utf-8 encoded string!
uint32_t name_size =
tag_module->size - sizeof(tag_module) + sizeof(char *);
tag_module->name = (char *)kalloc(name_size);
memcpy(tag_module->name, tag_module + tag_module->size - name_size,
name_size);
kfree(tag_module->name);
}
void read_mb2(mb2_tag_header *multiboot_bootinfo, uint32_t multiboot_magic)
{
if (multiboot_magic != MB2_MAGIC) {
// not loaded by multiboot2 bootloader
__asm__ __volatile__("hlt;");
}
// we will store framebuffer information here
static mb2_tag_fb *tag_fb;
static mb2_tag_mmap *tag_mmap;
// skip first 8 bytes (total_size + reserved)
mb2_tag_header *tag_header =
(mb2_tag_header *)((uint64_t)multiboot_bootinfo + 8 +
KERNEL_VMA);
while (tag_header->type != MB2_TAG_END) {
// process tag_type
switch (tag_header->type) {
case MB2_TAG_FB:
tag_fb = (mb2_tag_fb *)tag_header;
break;
case MB2_TAG_MMAP:
tag_mmap = (mb2_tag_mmap *)tag_header;
break;
case MB2_TAG_MODULE:
ext2_module = (mb2_tag_module *)tag_header;
break;
default:
break;
}
// next mb2_tag
tag_header +=
tag_header->size / 8 + ((tag_header->size % 8) > 0);
}
init_fb(tag_fb);
init_mmap(tag_mmap);
init_module(ext2_module);
}
|
