diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/Ia32/Thunk16.S')
| -rw-r--r-- | MdePkg/Library/BaseLib/Ia32/Thunk16.S | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/Thunk16.S b/MdePkg/Library/BaseLib/Ia32/Thunk16.S deleted file mode 100644 index 185655eecb..0000000000 --- a/MdePkg/Library/BaseLib/Ia32/Thunk16.S +++ /dev/null @@ -1,222 +0,0 @@ -#------------------------------------------------------------------------------
-#
-# Copyright (c) 2006 - 2013, 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.
-#
-# Module Name:
-#
-# Thunk16.S
-#
-# Abstract:
-#
-# Real mode thunk
-#
-#------------------------------------------------------------------------------
-
-#include <Library/BaseLib.h>
-
-ASM_GLOBAL ASM_PFX(m16Start), ASM_PFX(m16Size), ASM_PFX(mThunk16Attr), ASM_PFX(m16Gdt), ASM_PFX(m16GdtrBase), ASM_PFX(mTransition)
-ASM_GLOBAL ASM_PFX(InternalAsmThunk16)
-
-# define the structure of IA32_REGS
-.set _EDI, 0 #size 4
-.set _ESI, 4 #size 4
-.set _EBP, 8 #size 4
-.set _ESP, 12 #size 4
-.set _EBX, 16 #size 4
-.set _EDX, 20 #size 4
-.set _ECX, 24 #size 4
-.set _EAX, 28 #size 4
-.set _DS, 32 #size 2
-.set _ES, 34 #size 2
-.set _FS, 36 #size 2
-.set _GS, 38 #size 2
-.set _EFLAGS, 40 #size 4
-.set _EIP, 44 #size 4
-.set _CS, 48 #size 2
-.set _SS, 50 #size 2
-.set IA32_REGS_SIZE, 52
-
- .text
- .code16
-
-ASM_PFX(m16Start):
-
-SavedGdt: .space 6
-
-ASM_PFX(BackFromUserCode):
- push %ss
- push %cs
-
- calll L_Base1 # push eip
-L_Base1:
- pushfl
- cli # disable interrupts
- push %gs
- push %fs
- push %es
- push %ds
- pushal
- .byte 0x66, 0xba # mov edx, imm32
-ASM_PFX(ThunkAttr): .space 4
- testb $THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15, %dl
- jz 1f
- movw $0x2401, %ax
- int $0x15
- cli # disable interrupts
- jnc 2f
-1:
- testb $THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL, %dl
- jz 2f
- inb $0x92, %al
- orb $2, %al
- outb %al, $0x92 # deactivate A20M#
-2:
- xorl %eax, %eax
- movw %ss, %ax
- leal IA32_REGS_SIZE(%esp), %ebp
- mov %ebp, (_ESP - IA32_REGS_SIZE)(%bp)
- mov (_EIP - IA32_REGS_SIZE)(%bp), %bx
- shll $4, %eax
- addl %eax, %ebp
- .byte 0x66, 0xb8 # mov eax, imm32
-SavedCr4: .space 4
- movl %eax, %cr4
- lgdtl %cs:(SavedGdt - L_Base1)(%bx)
- .byte 0x66, 0xb8 # mov eax, imm32
-SavedCr0: .space 4
- movl %eax, %cr0
- .byte 0xb8 # mov ax, imm16
-SavedSs: .space 2
- movl %eax, %ss
- .byte 0x66, 0xbc # mov esp, imm32
-SavedEsp: .space 4
- lretl # return to protected mode
-
-_EntryPoint: .long ASM_PFX(ToUserCode) - ASM_PFX(m16Start)
- .word 0x8
-_16Idtr: .word 0x3ff
- .long 0
-_16Gdtr: .word GdtEnd - _NullSegDesc - 1
-_16GdtrBase: .long _NullSegDesc
-
-ASM_PFX(ToUserCode):
- movw %ss, %dx
- movw %cx, %ss # set new segment selectors
- movw %cx, %ds
- movw %cx, %es
- movw %cx, %fs
- movw %cx, %gs
- movl %eax, %cr0 # real mode starts at next instruction
- # which (per SDM) *must* be a far JMP.
- ljmpw $0,$0 # will be filled in by InternalAsmThunk16
-L_Base: # to point here.
- movl %ebp, %cr4
- movw %si, %ss # set up 16-bit stack segment
- xchgl %ebx, %esp # set up 16-bit stack pointer
-
- movw IA32_REGS_SIZE(%esp), %bp # get BackToUserCode address from stack
- mov %dx, %cs:(SavedSs - ASM_PFX(BackFromUserCode))(%bp)
- mov %ebx, %cs:(SavedEsp - ASM_PFX(BackFromUserCode))(%bp)
- lidtl %cs:(_16Idtr - ASM_PFX(BackFromUserCode))(%bp)
- popal
- pop %ds
- pop %es
- pop %fs
- pop %gs
- popfl
- lretl # transfer control to user code
-
-_NullSegDesc: .quad 0
-_16CsDesc:
- .word -1
- .word 0
- .byte 0
- .byte 0x9b
- .byte 0x8f # 16-bit segment, 4GB limit
- .byte 0
-_16DsDesc:
- .word -1
- .word 0
- .byte 0
- .byte 0x93
- .byte 0x8f # 16-bit segment, 4GB limit
- .byte 0
-GdtEnd:
-
- .code32
-#
-# @param RegSet The pointer to a IA32_DWORD_REGS structure
-# @param Transition The pointer to the transition code
-# @return The address of the 16-bit stack after returning from user code
-#
-ASM_PFX(InternalAsmThunk16):
- push %ebp
- push %ebx
- push %esi
- push %edi
- push %ds
- push %es
- push %fs
- push %gs
- movl 36(%esp), %esi # esi <- RegSet
- movzwl _SS(%esi), %edx
- mov _ESP(%esi), %edi
- add $(-(IA32_REGS_SIZE + 4)), %edi
- movl %edi, %ebx # ebx <- stack offset
- imul $0x10, %edx, %eax
- push $(IA32_REGS_SIZE / 4)
- addl %eax, %edi # edi <- linear address of 16-bit stack
- pop %ecx
- rep
- movsl # copy RegSet
- movl 40(%esp), %eax # eax <- address of transition code
- movl %edx, %esi # esi <- 16-bit stack segment
- lea (SavedCr0 - ASM_PFX(m16Start))(%eax), %edx
- movl %eax, %ecx
- andl $0xf, %ecx
- shll $12, %eax
- lea (ASM_PFX(BackFromUserCode) - ASM_PFX(m16Start))(%ecx), %ecx
- movw %cx, %ax
- stosl # [edi] <- return address of user code
- addl $(L_Base - ASM_PFX(BackFromUserCode)), %eax
- movl %eax, (L_Base - SavedCr0 - 4)(%edx)
- sgdtl (SavedGdt - SavedCr0)(%edx)
- sidtl 0x24(%esp)
- movl %cr0, %eax
- movl %eax, (%edx) # save CR0 in SavedCr0
- andl $0x7ffffffe, %eax # clear PE, PG bits
- movl %cr4, %ebp
- mov %ebp, (SavedCr4 - SavedCr0)(%edx)
- andl $0xffffffcf, %ebp # clear PAE, PSE bits
- pushl $0x10
- pop %ecx # ecx <- selector for data segments
- lgdtl (_16Gdtr - SavedCr0)(%edx)
- pushfl
- lcall *(_EntryPoint - SavedCr0)(%edx)
- popfl
- lidtl 0x24(%esp)
- lea -IA32_REGS_SIZE(%ebp), %eax
- pop %gs
- pop %fs
- pop %es
- pop %ds
- pop %edi
- pop %esi
- pop %ebx
- pop %ebp
- ret
-
- .const:
-
-ASM_PFX(m16Size): .word ASM_PFX(InternalAsmThunk16) - ASM_PFX(m16Start)
-ASM_PFX(mThunk16Attr): .word ASM_PFX(ThunkAttr) - ASM_PFX(m16Start)
-ASM_PFX(m16Gdt): .word _NullSegDesc - ASM_PFX(m16Start)
-ASM_PFX(m16GdtrBase): .word _16GdtrBase - ASM_PFX(m16Start)
-ASM_PFX(mTransition): .word _EntryPoint - ASM_PFX(m16Start)
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