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@naoki9911 naoki9911/entry.S
Last active Sep 15, 2018

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.globl _start
_start = V2P_WO(entry)
.globl wait_main
.long 0
# Entering xv6 on boot processor, with paging off.
.globl entry
#Set Data Segment
mov $0x10,%ax
mov %ax,%ds
mov %ax,%es
mov %ax,%ss
mov $0,%ax
mov %ax,%fs
mov %ax,%gs
#Turn off paing
movl %cr0,%eax
andl $0x7fffffff,%eax
movl %eax,%cr0
#Set Page Table Base Address
movl $(V2P_WO(entrypgdir)), %eax
movl %eax, %cr3
#Disable IA32e mode
movl $0x0c0000080,%ecx
andl $0xFFFFFEFF,%eax
# Turn on page size extension for 4Mbyte pages
movl %cr4, %eax
orl $(CR4_PSE), %eax
andl $0xFFFFFFDF, %eax
movl %eax, %cr4
#Turn on Paging
movl %cr0, %eax
orl $0x80010001, %eax
movl %eax, %cr0
# Set up the stack pointer.
movl $(stack + KSTACKSIZE), %esp
# Jump to main(), and switch to executing at
# high addresses. The indirect call is needed because
# the assembler produces a PC-relative instruction
# for a direct jump.
# jz .waiting_main
movl $main, %edx
jmp %edx
.comm stack, KSTACKSIZE
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