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/* Check if the compiler thinks you are targeting the wrong operating system. */
#if defined(__linux__)
#error "You are not using a cross-compiler"
#endif
/* This tutorial will only work for the 32-bit ix86 targets. */
#if !defined(__i386__)
#error "This tutorial needs to be compiled with a ix86-elf compiler"
#endif
#include "multiboot2.h"
#include "vga.h"
#include <stdlib.h>
#include <types.h>
extern "C" void kernel_main(uint32_t mb_magic, uint32_t mb_addr) {
VGA terminal;
Console::set(&terminal);
printk("Hello, kernel World!\n");
printk("multiboot magic: 0x", mb_magic,
mb_magic == MULTIBOOT2_BOOTLOADER_MAGIC ? " is valid" : " is invalid",
'\n');
printk("multiboot addr: 0x", mb_addr, '\n');
if (mb_addr & 7) {
printk("unaligned mbi\n");
}
struct multiboot_tag *tag;
const uint32_t size = *(unsigned *)mb_addr;
printk("Announced mbi size 0x", size, '\n');
for (tag = (struct multiboot_tag *)(mb_addr + 8);
tag->type != MULTIBOOT_TAG_TYPE_END;
tag = (struct multiboot_tag *)((multiboot_uint8_t *)tag +
((tag->size + 7) & ~7))) {
switch (tag->type) {
case MULTIBOOT_TAG_TYPE_CMDLINE:
printk("Command line = [", ((struct multiboot_tag_string *)tag)->string,
"]\n");
break;
case MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME:
printk("Boot loader name = [",
((struct multiboot_tag_string *)tag)->string, "]\n");
break;
case MULTIBOOT_TAG_TYPE_BASIC_MEMINFO:
printk("mem_lower = ",
((struct multiboot_tag_basic_meminfo *)tag)->mem_lower, "KB\n",
"mem_upper = ",
((struct multiboot_tag_basic_meminfo *)tag)->mem_upper, "KB\n");
break;
case MULTIBOOT_TAG_TYPE_BOOTDEV:
printk("Boot device 0x", ((struct multiboot_tag_bootdev *)tag)->biosdev,
" slice ", ((struct multiboot_tag_bootdev *)tag)->slice, " part ",
((struct multiboot_tag_bootdev *)tag)->part, '\n');
break;
case MULTIBOOT_TAG_TYPE_MMAP: {
multiboot_memory_map_t *mmap;
printk("mmap\n");
for (mmap = ((struct multiboot_tag_mmap *)tag)->entries;
(multiboot_uint8_t *)mmap < (multiboot_uint8_t *)tag + tag->size;
mmap = (multiboot_memory_map_t *)((unsigned long)mmap +
((struct multiboot_tag_mmap *)tag)
->entry_size))
printk(" base_addr = 0x", (unsigned)(mmap->addr >> 32), ' ',
(unsigned)(mmap->addr & 0xffffffff), " length = 0x",
(unsigned)(mmap->len >> 32), ' ',
(unsigned)(mmap->len & 0xffffffff), " type = 0x",
(unsigned)mmap->type, '\n');
} break;
default:
printk("Tag 0x", tag->type, ", Size 0x", tag->size, '\n');
break;
} // switch(tag->type)
} // for(each tag)
tag = (struct multiboot_tag *)((multiboot_uint8_t *)tag +
((tag->size + 7) & ~7));
printk("Total mbi size 0x", (unsigned)tag - mb_addr, '\n');
abort();
}
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