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Code: Select all

# Define the contnts of the Multiboot Header
.set MAGIC,		0xE85250D6
.set ARCH,		0
.set LENGTH,	(multiboot_header_end - multiboot_header)
.set CHECKSUM,	-(MAGIC + ARCH + LENGTH)

# Store the contents of the Multiboot header at the beginning of the file.
.section .multiboot
.align 8								# Align the section on the 64-bit boundary.
multiboot_header:
.long MAGIC
.long ARCH
.long LENGTH
.long CHECKSUM
multiboot_info_req:
.short 1
.short 0
.long (multiboot_info_req_end - multiboot_info_req)
.long 4
.long 6
multiboot_info_req_end:
.short 0
.short 0
.long 8
multiboot_header_end:

Code: Select all

#include <sys/sys.h>
#include <sys/multiboot2.h>
#include <kernel/tty.h>
#include <libc/stdio.h>

#include <stdint.h>

struct multiboot2_data {
    multiboot_uint32_t totalSize;
    multiboot_uint32_t reserved;
    struct multiboot_tag_basic_meminfo memInfo;
    struct multiboot_tag_mmap mmapInfo;
};

extern "C" void _main(struct multiboot2_data* mbd) {
    gdt_install();
    idt_install();
    terminal_initialize();
    terminal_writestring("Hello World! \n");
    struct multiboot_tag_basic_meminfo memInfo = mbd->memInfo;
    printf("Lower Memory: %x\n", memInfo.mem_lower);
    printf("Version: 0.0.0.1d\n");
    for(;;);
}