| 53,11 → 53,11 |
|---|
| xorw %ax, %ax |
| movw %ax, %ds |
| movw %ax, %ss # initialize stack segment register |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| |
| call memmap_arch_init |
| |
| lgdt real_bootstrap_gdtr_boot # initialize Global Descriptor Table register |
| lgdt real_bootstrap_gdtr_boot # initialize Global Descriptor Table register |
| |
| movl %cr0, %eax |
| orl $0x1, %eax |
| 82,10 → 82,10 |
|---|
| movw %ax, %es |
| movw %ax, %gs |
| movw %ax, %fs |
| movw %ax, %ds # kernel data + stack |
| movw %ax, %ds # kernel data + stack |
| movw %ax, %ss |
| |
| movb $0xd1, %al # enable A20 using the keyboard controller |
| movb $0xd1, %al # enable A20 using the keyboard controller |
| outb %al, $0x64 |
| movb $0xdf, %al |
| outb %al, $0x60 |
| 96,29 → 96,29 |
|---|
| cld |
| rep movsb |
| |
| call map_kernel # map kernel and turn paging on |
| call map_kernel # map kernel and turn paging on |
| |
| call main_bsp # never returns |
| call main_bsp # never returns |
| |
| cli |
| hlt |
| |
| multiboot_image_start: |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| |
| lgdt protected_bootstrap_gdtr - 0x80000000 # initialize Global Descriptor Table register |
| lgdt protected_bootstrap_gdtr - 0x80000000 # initialize Global Descriptor Table register |
| |
| movw $KDATA, %cx |
| movw %cx, %es |
| movw %cx, %gs |
| movw %cx, %fs |
| movw %cx, %ds # kernel data + stack |
| movw %cx, %ds # kernel data + stack |
| movw %cx, %ss |
| |
| jmpl $KTEXT, $multiboot_meeting_point + BOOT_OFFSET |
| multiboot_meeting_point: |
| |
| pushl %ebx # save parameters from GRUB |
| pushl %ebx # save parameters from GRUB |
| pushl %eax |
| |
| movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %esi |
| 127,11 → 127,11 |
|---|
| cld |
| rep movsb |
| |
| call map_kernel # map kernel and turn paging on |
| call map_kernel # map kernel and turn paging on |
| |
| popl %eax |
| popl %ebx |
| cmpl $MULTIBOOT_LOADER_MAGIC, %eax # compare GRUB signature |
| cmpl $MULTIBOOT_LOADER_MAGIC, %eax # compare GRUB signature |
| je valid_boot |
| |
| xorl %ecx, %ecx # no memory size or map available |
| 203,7 → 203,7 |
|---|
| |
| invalid_boot: |
| |
| call main_bsp - BOOT_OFFSET # never returns |
| call main_bsp - BOOT_OFFSET # never returns |
| |
| cli |
| hlt |
| 216,13 → 216,13 |
|---|
| # |
| movl %cr4, %ecx |
| orl $(1<<4), %ecx |
| movl %ecx, %cr4 # turn PSE on |
| movl %ecx, %cr4 # turn PSE on |
| |
| movl $((1<<7)|(1<<0)), %eax |
| movl %eax, page_directory # mapping 0x00000000 => 0x00000000 |
| movl %eax, page_directory # mapping 0x00000000 => 0x00000000 |
| |
| movl $(page_directory+2048), %edx |
| movl %eax, (%edx) # mapping 0x80000000 => 0x00000000 |
| movl %eax, (%edx) # mapping 0x80000000 => 0x00000000 |
| |
| leal page_directory, %eax |
| movl %eax, %cr3 |