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#include <linux/config.h>
.section __xen_guest
.ascii "GUEST_OS=linux,GUEST_VER=2.6,XEN_VER=2.0,VIRT_BASE=0xC0000000"
.ascii ",LOADER=generic"
#ifdef CONFIG_XEN_WRITABLE_PAGETABLES
.ascii ",PT_MODE_WRITABLE"
#endif
.byte 0
.text
#include <linux/threads.h>
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/thread_info.h>
#include <asm/asm_offsets.h>
#include <asm/hypervisor-ifs/arch-x86_32.h>
/*
* References to members of the new_cpu_data structure.
*/
#define X86 new_cpu_data+CPUINFO_x86
#define X86_VENDOR new_cpu_data+CPUINFO_x86_vendor
#define X86_MODEL new_cpu_data+CPUINFO_x86_model
#define X86_MASK new_cpu_data+CPUINFO_x86_mask
#define X86_HARD_MATH new_cpu_data+CPUINFO_hard_math
#define X86_CPUID new_cpu_data+CPUINFO_cpuid_level
#define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability
#define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id
ENTRY(startup_32)
cld
/* Set up the stack pointer */
lss stack_start,%esp
/* Copy the necessary stuff from xen_start_info structure. */
mov $xen_start_info_union,%edi
mov $128,%ecx
rep movsl
checkCPUtype:
/* get vendor info */
xorl %eax,%eax # call CPUID with 0 -> return vendor ID
cpuid
movl %eax,X86_CPUID # save CPUID level
movl %ebx,X86_VENDOR_ID # lo 4 chars
movl %edx,X86_VENDOR_ID+4 # next 4 chars
movl %ecx,X86_VENDOR_ID+8 # last 4 chars
movl $1,%eax # Use the CPUID instruction to get CPU type
cpuid
movb %al,%cl # save reg for future use
andb $0x0f,%ah # mask processor family
movb %ah,X86
andb $0xf0,%al # mask model
shrb $4,%al
movb %al,X86_MODEL
andb $0x0f,%cl # mask mask revision
movb %cl,X86_MASK
movl %edx,X86_CAPABILITY
xorl %eax,%eax # Clear FS/GS and LDT
movl %eax,%fs
movl %eax,%gs
cld # gcc2 wants the direction flag cleared at all times
call start_kernel
L6:
jmp L6 # main should never return here, but
# just in case, we know what happens.
ENTRY(lgdt_finish)
movl $(__KERNEL_DS),%eax # reload all the segment registers
movw %ax,%ss # after changing gdt.
movl $(__USER_DS),%eax # DS/ES contains default USER segment
movw %ax,%ds
movw %ax,%es
popl %eax # reload CS by intersegment return
pushl $(__KERNEL_CS)
pushl %eax
lret
ENTRY(stack_start)
.long init_thread_union+THREAD_SIZE
.long __BOOT_DS
# XXXcl
.globl idt_descr
.globl cpu_gdt_descr
ALIGN
.word 0 # 32-bit align idt_desc.address
idt_descr:
.word IDT_ENTRIES*8-1 # idt contains 256 entries
.long idt_table
# XXXcl
# boot GDT descriptor (later on used by CPU#0):
.word 0 # 32 bit align gdt_desc.address
cpu_gdt_descr:
.word GDT_SIZE
.long cpu_gdt_table
.fill NR_CPUS-1,8,0 # space for the other GDT descriptors
.org 0x1000
ENTRY(empty_zero_page)
.org 0x2000
ENTRY(swapper_pg_dir)
.org 0x3000
ENTRY(cpu_gdt_table)
.quad 0x0000000000000000 /* NULL descriptor */
.quad 0x0000000000000000 /* 0x0b reserved */
.quad 0x0000000000000000 /* 0x13 reserved */
.quad 0x0000000000000000 /* 0x1b reserved */
.quad 0x0000000000000000 /* 0x20 unused */
.quad 0x0000000000000000 /* 0x28 unused */
.quad 0x0000000000000000 /* 0x33 TLS entry 1 */
.quad 0x0000000000000000 /* 0x3b TLS entry 2 */
.quad 0x0000000000000000 /* 0x43 TLS entry 3 */
.quad 0x0000000000000000 /* 0x4b reserved */
.quad 0x0000000000000000 /* 0x53 reserved */
.quad 0x0000000000000000 /* 0x5b reserved */
.quad 0x00cfbb000000c3ff /* 0x60 kernel 4GB code at 0x00000000 */
.quad 0x00cfb3000000c3ff /* 0x68 kernel 4GB data at 0x00000000 */
.quad 0x00cffb000000c3ff /* 0x73 user 4GB code at 0x00000000 */
.quad 0x00cff3000000c3ff /* 0x7b user 4GB data at 0x00000000 */
.quad 0x0000000000000000 /* 0x80 TSS descriptor */
.quad 0x0000000000000000 /* 0x88 LDT descriptor */
/* Segments used for calling PnP BIOS */
.quad 0x0000000000000000 /* 0x90 32-bit code */
.quad 0x0000000000000000 /* 0x98 16-bit code */
.quad 0x0000000000000000 /* 0xa0 16-bit data */
.quad 0x0000000000000000 /* 0xa8 16-bit data */
.quad 0x0000000000000000 /* 0xb0 16-bit data */
/*
* The APM segments have byte granularity and their bases
* and limits are set at run time.
*/
.quad 0x0000000000000000 /* 0xb8 APM CS code */
.quad 0x0000000000000000 /* 0xc0 APM CS 16 code (16 bit) */
.quad 0x0000000000000000 /* 0xc8 APM DS data */
.quad 0x0000000000000000 /* 0xd0 - unused */
.quad 0x0000000000000000 /* 0xd8 - unused */
.quad 0x0000000000000000 /* 0xe0 - unused */
.quad 0x0000000000000000 /* 0xe8 - unused */
.quad 0x0000000000000000 /* 0xf0 - unused */
.quad 0x0000000000000000 /* 0xf8 - GDT entry 31: double-fault TSS */
.fill GDT_ENTRIES-32,8,0
.org 0x4000
ENTRY(default_ldt)
.org 0x5000
/*
* Real beginning of normal "text" segment
*/
ENTRY(stext)
ENTRY(_stext)
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