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;------------------------------------------------------------------------------
; @file
; An entry point use by Xen when a guest is started in PVH mode.
;
; Copyright (c) 2019, Citrix Systems, Inc.
;
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
BITS 32
xenPVHMain:
;
; 'BP' to indicate boot-strap processor
;
mov di, 'BP'
;
; ESP will be used as initial value of the EAX register
; in Main.asm
;
xor esp, esp
;
; Store "Start of day" struct pointer for later use
;
mov dword[PVH_SPACE (0)], ebx
mov dword[PVH_SPACE (4)], 'XPVH'
mov ebx, ADDR_OF(gdtr)
lgdt [ebx]
mov eax, SEC_DEFAULT_CR0
mov cr0, eax
jmp LINEAR_CODE_SEL:ADDR_OF(.jmpToNewCodeSeg)
.jmpToNewCodeSeg:
mov eax, SEC_DEFAULT_CR4
mov cr4, eax
mov ax, LINEAR_SEL
mov ds, ax
mov es, ax
mov fs, ax
mov gs, ax
mov ss, ax
;
; Jump to the main routine of the pre-SEC code
; skiping the 16-bit part of the routine and
; into the 32-bit flat mode part
;
OneTimeCallRet TransitionFromReal16To32BitFlat
|
