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-rw-r--r--entryother.S60
1 files changed, 0 insertions, 60 deletions
diff --git a/entryother.S b/entryother.S
deleted file mode 100644
index dd33680..0000000
--- a/entryother.S
+++ /dev/null
@@ -1,60 +0,0 @@
-#include "asm.h"
-#include "memlayout.h"
-#include "mmu.h"
-
-# Each non-boot CPU ("AP") is started up in response to a STARTUP
-# IPI from the boot CPU. Section B.4.2 of the Multi-Processor
-# Specification says that the AP will start in real mode with CS:IP
-# set to XY00:0000, where XY is an 8-bit value sent with the
-# STARTUP. Thus this code must start at a 4096-byte boundary.
-#
-# Because this code sets DS to zero, it must sit
-# at an address in the low 2^16 bytes.
-#
-# Startothers (in main.c) sends the STARTUPs one at a time.
-# It copies this code (start) at 0x7000. It puts the address of
-# a newly allocated per-core stack in start-12,the address of the
-# place to jump to (apstart32) in start-4, and the physical address
-# of entrypgdir in start-12.
-
-.code16
-.globl start
-start:
- cli
-
- # Zero data segment registers DS, ES, and SS.
- xorw %ax,%ax
- movw %ax,%ds
- movw %ax,%es
- movw %ax,%ss
-
- # Switch from real to protected mode. Use a bootstrap GDT that makes
- # virtual addresses map directly to physical addresses so that the
- # effective memory map doesn't change during the transition.
- lgdt gdtdesc
- movl %cr0, %eax
- orl $CR0_PE, %eax
- movl %eax, %cr0
-
- # Complete the transition to 32-bit protected mode by using a long jmp
- # to reload %cs and %eip. The segment descriptors are set up with no
- # translation, so that the mapping is still the identity mapping.
- ljmpl $(SEG_KCODE32), $start32
-
-.code32
-start32:
- movl $start-12, %esp
- movl start-4, %ecx
- jmp *%ecx
-
-.align 4
-gdt:
- SEG_NULLASM
- SEG_ASM(0xa, 0, 0xffffffff)
- SEG_ASM(0x2, 0, 0xffffffff)
-
-.align 16
-gdtdesc:
- .word 0x17 # sizeof(gdt)-1
- .long gdt
-