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#------------------------------------------------------------------------------
#*
#* Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
#* This program and the accompanying materials
#* are licensed and made available under the terms and conditions of the BSD License
#* which accompanies this distribution. The full text of the license may be found at
#* http://opensource.org/licenses/bsd-license.php
#*
#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#*
#* CpuAsm.S
#*
#* Abstract:
#*
#------------------------------------------------------------------------------
#.MMX
#.XMM
#EXTRN ASM_PFX(mErrorCodeFlag):DWORD # Error code flags for exceptions
#
# point to the external interrupt vector table
#
ExternalVectorTablePtr:
.byte 0, 0, 0, 0
ASM_GLOBAL ASM_PFX(InitializeExternalVectorTablePtr)
ASM_PFX(InitializeExternalVectorTablePtr):
movl 4(%esp), %eax
movl %eax, ExternalVectorTablePtr
ret
#------------------------------------------------------------------------------
# VOID
# SetCodeSelector (
# UINT16 Selector
# );
#------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(SetCodeSelector)
ASM_PFX(SetCodeSelector):
movl 4(%esp), %ecx
subl $0x10, %esp
leal setCodeSelectorLongJump, %eax
movl %eax, (%esp)
movw %cx, 4(%esp)
.byte 0xFF, 0x2C, 0x24 # jmp *(%esp) note:(FWORD jmp)
setCodeSelectorLongJump:
addl $0x10, %esp
ret
#------------------------------------------------------------------------------
# VOID
# SetDataSelectors (
# UINT16 Selector
# );
#------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(SetDataSelectors)
ASM_PFX(SetDataSelectors):
movl 4(%esp), %ecx
movw %cx, %ss
movw %cx, %ds
movw %cx, %es
movw %cx, %fs
movw %cx, %gs
ret
#---------------------------------------;
# CommonInterruptEntry ;
#---------------------------------------;
# The follow algorithm is used for the common interrupt routine.
ASM_GLOBAL ASM_PFX(CommonInterruptEntry)
ASM_PFX(CommonInterruptEntry):
cli
#
# All interrupt handlers are invoked through interrupt gates, so
# IF flag automatically cleared at the entry point
#
#
# Calculate vector number
#
# Get the return address of call, actually, it is the
# address of vector number.
#
xchgl (%esp), %ecx
movw (%ecx), %cx
andl $0x0FFFF, %ecx
cmpl $32, %ecx # Intel reserved vector for exceptions?
jae NoErrorCode
bt %ecx, ASM_PFX(mErrorCodeFlag)
jc HasErrorCode
NoErrorCode:
#
# Stack:
# +---------------------+
# + EFlags +
# +---------------------+
# + CS +
# +---------------------+
# + EIP +
# +---------------------+
# + ECX +
# +---------------------+ <-- ESP
#
# Registers:
# ECX - Vector Number
#
#
# Put Vector Number on stack
#
pushl %ecx
#
# Put 0 (dummy) error code on stack, and restore ECX
#
xorl %ecx, %ecx # ECX = 0
xchgl 4(%esp), %ecx
jmp ErrorCodeAndVectorOnStack
HasErrorCode:
#
# Stack:
# +---------------------+
# + EFlags +
# +---------------------+
# + CS +
# +---------------------+
# + EIP +
# +---------------------+
# + Error Code +
# +---------------------+
# + ECX +
# +---------------------+ <-- ESP
#
# Registers:
# ECX - Vector Number
#
#
# Put Vector Number on stack and restore ECX
#
xchgl (%esp), %ecx
#
# Fall through to join main routine code
# at ErrorCodeAndVectorOnStack
#
CommonInterruptEntry_al_0000:
jmp CommonInterruptEntry_al_0000
ErrorCodeAndVectorOnStack:
pushl %ebp
movl %esp, %ebp
#
# Stack:
# +---------------------+
# + EFlags +
# +---------------------+
# + CS +
# +---------------------+
# + EIP +
# +---------------------+
# + Error Code +
# +---------------------+
# + Vector Number +
# +---------------------+
# + EBP +
# +---------------------+ <-- EBP
#
#
# Align stack to make sure that EFI_FX_SAVE_STATE_IA32 of EFI_SYSTEM_CONTEXT_IA32
# is 16-byte aligned
#
andl $0x0fffffff0, %esp
subl $12, %esp
#; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;
pushl %eax
pushl %ecx
pushl %edx
pushl %ebx
leal 24(%ebp), %ecx
pushl %ecx # ESP
pushl (%ebp) # EBP
pushl %esi
pushl %edi
#; UINT32 Gs, Fs, Es, Ds, Cs, Ss;
movl %ss, %eax
pushl %eax
movzwl 16(%ebp), %eax
pushl %eax
movl %ds, %eax
pushl %eax
movl %es, %eax
pushl %eax
movl %fs, %eax
pushl %eax
movl %gs, %eax
pushl %eax
#; UINT32 Eip;
movl 12(%ebp), %eax
pushl %eax
#; UINT32 Gdtr[2], Idtr[2];
subl $8, %esp
sidt (%esp)
movl 2(%esp), %eax
xchgl (%esp), %eax
andl $0x0FFFF, %eax
movl %eax, 4(%esp)
subl $8, %esp
sgdt (%esp)
movl 2(%esp), %eax
xchgl (%esp), %eax
andl $0x0FFFF, %eax
movl %eax, 4(%esp)
#; UINT32 Ldtr, Tr;
xorl %eax, %eax
str %ax
pushl %eax
sldt %ax
pushl %eax
#; UINT32 EFlags;
movl 20(%ebp), %eax
pushl %eax
#; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
movl %cr4, %eax
orl $0x208, %eax
movl %eax, %cr4
pushl %eax
movl %cr3, %eax
pushl %eax
movl %cr2, %eax
pushl %eax
xorl %eax, %eax
pushl %eax
movl %cr0, %eax
pushl %eax
#; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
movl %dr7, %eax
pushl %eax
movl %dr6, %eax
pushl %eax
movl %dr3, %eax
pushl %eax
movl %dr2, %eax
pushl %eax
movl %dr1, %eax
pushl %eax
movl %dr0, %eax
pushl %eax
#; FX_SAVE_STATE_IA32 FxSaveState;
subl $512, %esp
movl %esp, %edi
.byte 0x0f, 0x0ae, 0x07 #fxsave [edi]
#; UINT32 ExceptionData;
pushl 8(%ebp)
#; call into exception handler
movl ExternalVectorTablePtr, %eax # get the interrupt vectors base
orl %eax, %eax # NULL?
jz nullExternalExceptionHandler
mov 4(%ebp), %ecx
movl (%eax,%ecx,4), %eax
orl %eax, %eax # NULL?
jz nullExternalExceptionHandler
#; Prepare parameter and call
movl %esp, %edx
pushl %edx
movl 4(%ebp), %edx
pushl %edx
#
# Call External Exception Handler
#
call *%eax
addl $8, %esp
nullExternalExceptionHandler:
cli
#; UINT32 ExceptionData;
addl $4, %esp
#; FX_SAVE_STATE_IA32 FxSaveState;
movl %esp, %esi
.byte 0x0f, 0x0ae, 0x0e # fxrstor [esi]
addl $512, %esp
#; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
#; Skip restoration of DRx registers to support in-circuit emualators
#; or debuggers set breakpoint in interrupt/exception context
addl $24, %esp
#; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
popl %eax
movl %eax, %cr0
addl $4, %esp # not for Cr1
popl %eax
movl %eax, %cr2
popl %eax
movl %eax, %cr3
popl %eax
movl %eax, %cr4
#; UINT32 EFlags;
popl 20(%ebp)
#; UINT32 Ldtr, Tr;
#; UINT32 Gdtr[2], Idtr[2];
#; Best not let anyone mess with these particular registers...
addl $24, %esp
#; UINT32 Eip;
popl 12(%ebp)
#; UINT32 Gs, Fs, Es, Ds, Cs, Ss;
#; NOTE - modified segment registers could hang the debugger... We
#; could attempt to insulate ourselves against this possibility,
#; but that poses risks as well.
#;
popl %gs
popl %fs
popl %es
popl %ds
popl 16(%ebp)
popl %ss
#; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;
popl %edi
popl %esi
addl $4, %esp # not for ebp
addl $4, %esp # not for esp
popl %ebx
popl %edx
popl %ecx
popl %eax
movl %ebp, %esp
popl %ebp
addl $8, %esp
iretl
#END
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