| 32,38 → 32,10 |
|---|
| #include <arch/pm.h> |
| |
| .section K_TEXT_START, "ax" |
| .global kernel_image_start |
| |
| KTEXT=8 |
| KDATA=16 |
| |
| .code16 |
| # |
| # This is where we require any SPARTAN-kernel-compatible boot loader |
| # to pass control in real mode. |
| # |
| # Protected mode tables are statically initialised during compile |
| # time. So we can just load the respective table registers and |
| # switch to protected mode. |
| # |
| kernel_image_start: |
| cli |
| xorw %ax, %ax |
| movw %ax, %ds |
| movw %ax, %es |
| movw %ax, %ss # initialize stack segment register |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| |
| call memmap_arch_init |
| |
| lgdt real_bootstrap_gdtr_boot # initialize Global Descriptor Table register |
| |
| movl %cr0, %eax |
| orl $0x1, %eax |
| movl %eax, %cr0 # switch to protected mode |
| |
| jmpl $KTEXT, $boot_image_start |
| |
| .code32 |
| .align 4 |
| multiboot_header: |
| 76,32 → 48,6 |
|---|
| .long 0 |
| .long multiboot_image_start + BOOT_OFFSET |
| |
| boot_image_start: |
| movw $KDATA, %ax |
| movw %ax, %es |
| movw %ax, %gs |
| movw %ax, %fs |
| movw %ax, %ds # kernel data + stack |
| movw %ax, %ss |
| |
| movb $0xd1, %al # enable A20 using i8042 controller |
| outb %al, $0x64 |
| movb $0xdf, %al |
| outb %al, $0x60 |
| |
| movl $BOOTSTRAP_OFFSET, %esi |
| movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %edi |
| movl $_hardcoded_kernel_size, %ecx |
| cld |
| rep movsb |
| |
| call map_kernel # map kernel and turn paging on |
| |
| call main_bsp # never returns |
| |
| cli |
| hlt |
| |
| multiboot_image_start: |
| movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer |
| |