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.text
#include <linux/config.h>
#include <linux/threads.h>
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <xen/interface/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)
movl %esi,xen_start_info
cld
/* Set up the stack pointer */
movl $(init_thread_union+THREAD_SIZE),%esp
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
movb $1,X86_HARD_MATH
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.
#define HYPERCALL_PAGE_OFFSET 0x1000
.org HYPERCALL_PAGE_OFFSET
ENTRY(hypercall_page)
.skip 0x1000
/*
* Real beginning of normal "text" segment
*/
ENTRY(stext)
ENTRY(_stext)
/*
* BSS section
*/
.section ".bss.page_aligned","w"
ENTRY(empty_zero_page)
.fill 4096,1,0
/*
* This starts the data section.
*/
.data
/*
* The Global Descriptor Table contains 28 quadwords, per-CPU.
*/
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 0x00cf9a000000ffff /* 0x60 kernel 4GB code at 0x00000000 */
.quad 0x00cf92000000ffff /* 0x68 kernel 4GB data at 0x00000000 */
.quad 0x00cffa000000ffff /* 0x73 user 4GB code at 0x00000000 */
.quad 0x00cff2000000ffff /* 0x7b user 4GB data at 0x00000000 */
.quad 0x0000000000000000 /* 0x80 TSS descriptor */
.quad 0x0000000000000000 /* 0x88 LDT descriptor */
/*
* Segments used for calling PnP BIOS have byte granularity.
* They code segments and data segments have fixed 64k limits,
* the transfer segment sizes are set at run time.
*/
.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
* are set at run time. All have 64k limits.
*/
.quad 0x0000000000000000 /* 0xb8 APM CS code */
.quad 0x0000000000000000 /* 0xc0 APM CS 16 code (16 bit) */
.quad 0x0000000000000000 /* 0xc8 APM DS data */
.quad 0x0000000000000000 /* 0xd0 - ESPFIX 16-bit SS */
.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 */
/*
* __xen_guest information
*/
.macro utoa value
.if (\value) < 0 || (\value) >= 0x10
utoa (((\value)>>4)&0x0fffffff)
.endif
.if ((\value) & 0xf) < 10
.byte '0' + ((\value) & 0xf)
.else
.byte 'A' + ((\value) & 0xf) - 10
.endif
.endm
.section __xen_guest
.ascii "GUEST_OS=linux,GUEST_VER=2.6"
.ascii ",XEN_VER=xen-3.0"
.ascii ",VIRT_BASE=0x"
utoa __PAGE_OFFSET
.ascii ",HYPERCALL_PAGE=0x"
utoa ((__PHYSICAL_START+HYPERCALL_PAGE_OFFSET)>>PAGE_SHIFT)
.ascii ",FEATURES=writable_page_tables"
.ascii "|writable_descriptor_tables"
.ascii "|auto_translated_physmap"
.ascii "|pae_pgdir_above_4gb"
.ascii "|supervisor_mode_kernel"
#ifdef CONFIG_X86_PAE
.ascii ",PAE=yes"
#else
.ascii ",PAE=no"
#endif
.ascii ",LOADER=generic"
.byte 0
|
