[mirror_edk2.git] / EdkCompatibilityPkg / Foundation / Library / Thunk16 / X64 / Thunk16.S

#*****************************************************************************
#*
#*   Copyright (c) 2008, Intel Corporation                                                         
#*   All rights reserved. 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:
#*
#*    Thunk.S
#*  
#*   Abstract:
#*  
#*    Real mode thunk
#*  
#*****************************************************************************
#include <EfiBind.h>


    .data

.globl ASM_PFX(mCode16Size)

.data
mCode16Size:    .long   _Code16End - _Code16Addr


NullSegSel:     .quad   0
_16CsSegSel:    
                .word   -1
                .word   0
                .byte   0
                .byte   0x9b
                .byte   0x8f            #16-bit segment
                .byte   0
_16DsSegSel:
                .word   -1
                .word   0
                .byte   0
                .byte   0x93
                .byte   0x8f           #16-bit segment
                .byte   0

_16Gdtr:
                .word      _16Gdtr - NullSegSel - 1
                .long      NullSegSel
    .code: 

#IA32_REGS   STRUC   4t\r
#_EDI        DD      ?\r
#_ESI        DD      ?\r
#_EBP        DD      ?\r
#_ESP        DD      ?\r
#_EBX        DD      ?\r
#_EDX        DD      ?\r
#_ECX        DD      ?\r
#_EAX        DD      ?\r
#_DS         DW      ?\r
#_ES         DW      ?\r
#_FS         DW      ?\r
#_GS         DW      ?\r
#_RFLAGS     DQ      ?\r
#_EIP        DD      ?\r
#_CS         DW      ?\r
#_SS         DW      ?\r
#IA32_REGS   ENDS\r
\r
#_STK16      STRUC   1t\r
#RetEip      DD      ?\r
#RetCs       DW      ?\r
#ThunkFlags  DW      ?\r
#SavedGdtr   FWORD   ?\r
#Resvd1      DW      ?\r
#SavedCr0    DD      ?\r
#SavedCr4    DD      ?\r
#_STK16      ENDS\r

ASM_PFX(Thunk16):
      push   %rbp
      push   %rbx
      push   %rsi
      push   %rdi
      push   %r12
      push   %r13
      push   %r14
      push   %r15
      pushq  %fs
      pushq  %gs
      movl   %ds,%r12d
      movl   %es,%r13d
      movl   %ss,%r14d
      mov    %rsp,%r15
      mov    %rcx,%rsi
      movzwq 0x36(%rsi),%r10            #movzx   r10, (IA32_REGS ptr [rsi])._SS
      xor    %rdi,%rdi
      mov    0xc(%rsi),%edi             #mov     edi, (IA32_REGS ptr [rsi])._ESP
      add    $0xffffffffffffffb0,%rdi   #add     rdi, - sizeof (IA32_REGS) - sizeof (_STK16)
      push   %rdi
      imul   $0x10,%r10,%rax
      add    %rax,%rdi
      pushq  $0xe                       #push    sizeof (IA32_REGS) / 4
      pop    %rcx
      rep movsl %ds:(%rsi),%es:(%rdi)
      pop    %rbx                       #rbx <- 16-bit stack offset
      lea    Label,%eax                 #42 <_Thunk16+0x42>
      stos   %eax,%es:(%rdi)
      movl   %cs,%eax                   #return segment
      stos   %ax,%es:(%rdi)
      mov    %edx,%eax                  #THUNK Flags
      stos   %ax,%es:(%rdi)
      sgdt  0x58(%rsp)                  #save GDTR
      mov    0x58(%rsp),%rax
      stos   %rax,%es:(%rdi)
      mov    %cr0,%rax                  #save CR0
      mov    %eax,%esi                  #esi <- CR0 to set
      stos   %eax,%es:(%rdi)
      mov    %cr4,%rax                  #save CR4
      stos   %eax,%es:(%rdi)
      sidt   0x58(%rsp)                 #save IDTR
      and    $0x7ffffffe,%esi           #clear PE & PG bits
      mov    %r10,%rdi                  #rdi <- 16-bit stack segment
      shl    $0x10,%r8
      push   %r8                        #far jmp address
      lea    Label_16Bit,%eax           
      push   %rax
      movw   $0x8,0x4(%rsp)
      lgdt   _16Gdtr                    #bugbug: may not match.
      lret   
Label_16Bit:
      .byte  0x66
      movl   $0xc0000080,%ecx
      mov    %rsi,%cr0                  #disable PE & PG        
      rdmsr  
      and    $0xfe,%ah
      wrmsr                             #clear LME bit
      mov    %cr4,%rax
      and    $0xcf,%al                  #clear PAE & PSE
      mov    %rax,%cr4
      lret   

Label:
      xor    %rax,%rax
      movl   %ss,%eax
      shl    $0x4,%eax
      add    %esp,%eax
      mov    %r15,%rsp
      lidt   0x58(%rsp)
      movl   %r12d,%ds
      movl   %r13d,%es
      movl   %r14d,%ss
      popq   %gs
      popq   %fs
      pop    %r15
      pop    %r14
      pop    %r13
      pop    %r12
      pop    %rdi
      pop    %rsi
      pop    %rbx
      pop    %rbp
      retq   


    .align 0x10

_Code16Addr:
ASM_PFX(RealMode):
    movl   %edi,%ss
    mov    %bx,%sp                     #set up 16-bit stack
   .byte   0x2e 
   .byte   0x0f 
   .byte   0x01
   .byte   0x1e\r
   .word   _16Idtr - _Code16Addr       #lidt _16Idtr\r
   .byte   0x66
   .byte   0x61                        #popad\r
   .byte   0x1f                        #pop ds\r
   .byte   0x07                        #pop es
    popq   %fs\r
    popq   %gs\r
    add    $0x8,%esp                   #skip RFLAGS\r
   .byte   0x67                        #test [esp + 0eh], 1
   .byte   0xf7    
   .byte   0x44
   .byte   0x24
   .byte   0x0e
   .byte   0x01
   .byte   0x00
    jz      1f
    pushfq                             #pushf, actually
1:
   .byte   0x0e                        #push cs
   .byte   0x68                        #push /iw
   .word   FarCallRet - _Code16Addr
    jz     2f
   .byte   0x66
    ljmp   *6(%esp)
2:    
   .byte   0x66
    ljmp   *4(%esp)
FarCallRet: 
   .byte   0x66
    push   $0x00                       #push a dword of zero
   .byte   0x66
    pushf                              #pushfd, actually
    pushq  %gs
    pushq  %fs
   .byte   0x06                        #push %es
   .byte   0x1e                        #push %ds
   .byte   0x66
   .byte   0x60
    cli
   .byte   0x66                        #sizeof (IA32_REGS) = 13 * 4 = 52
    lgdt   64(%esp)                    #lgdt    (_STK16 ptr [esp + sizeof (IA32_REGS)]).SavedGdtr
   .byte   0x66
    mov    76(%esp), %eax
    mov    %rax, %cr4
   .byte   0x66
    mov    $0xc0000080, %ecx
    rdmsr
    orb    $1, %ah
    wrmsr
   .byte   0x66
    mov    72(%esp), %eax
    mov    %rax, %cr0                   #restore CR0
   .byte   0x66
    ljmpl  *52(%esp)                    

_16Idtr:
   .word 0x3ff                          #FWORD   (1 SHL 10) - 1
   .byte 0x00
Commit	Line	Data
21a54a4d	1	#*****************************************************************************
	2	#*
	3	#* Copyright (c) 2008, Intel Corporation
	4	#* All rights reserved. This program and the accompanying materials
	5	#* are licensed and made available under the terms and conditions of the BSD License
	6	#* which accompanies this distribution. The full text of the license may be found at
	7	#* http://opensource.org/licenses/bsd-license.php
	8	#*
	9	#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
	10	#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
	11	#*
	12	#* Module Name:
	13	#*
	14	#* Thunk.S
	15	#*
	16	#* Abstract:
	17	#*
	18	#* Real mode thunk
	19	#*
	20	#*****************************************************************************
	21	#include <EfiBind.h>
	22
	23
	24
	25	.data
	26
	27	.globl ASM_PFX(mCode16Size)
	28
	29	.data
	30	mCode16Size: .long _Code16End - _Code16Addr
	31
	32
	33	NullSegSel: .quad 0
	34	_16CsSegSel:
	35	.word -1
	36	.word 0
	37	.byte 0
	38	.byte 0x9b
	39	.byte 0x8f #16-bit segment
	40	.byte 0
	41	_16DsSegSel:
	42	.word -1
	43	.word 0
	44	.byte 0
	45	.byte 0x93
	46	.byte 0x8f #16-bit segment
	47	.byte 0
	48
	49	_16Gdtr:
	50	.word _16Gdtr - NullSegSel - 1
	51	.long NullSegSel
	52	.code:
	53
	54	#IA32_REGS STRUC 4t\r
	55	#_EDI DD ?\r
	56	#_ESI DD ?\r
	57	#_EBP DD ?\r
	58	#_ESP DD ?\r
	59	#_EBX DD ?\r
	60	#_EDX DD ?\r
	61	#_ECX DD ?\r
	62	#_EAX DD ?\r
	63	#_DS DW ?\r
	64	#_ES DW ?\r
65	#_FS DW ?\r
66	#_GS DW ?\r
67	#_RFLAGS DQ ?\r
68	#_EIP DD ?\r
69	#_CS DW ?\r
70	#_SS DW ?\r
71	#IA32_REGS ENDS\r
72	\r
73	#_STK16 STRUC 1t\r
74	#RetEip DD ?\r
75	#RetCs DW ?\r
76	#ThunkFlags DW ?\r
77	#SavedGdtr FWORD ?\r
78	#Resvd1 DW ?\r
79	#SavedCr0 DD ?\r
80	#SavedCr4 DD ?\r
81	#_STK16 ENDS\r
82
83	ASM_PFX(Thunk16):
84	push %rbp
85	push %rbx
86	push %rsi
87	push %rdi
88	push %r12
89	push %r13
90	push %r14
91	push %r15
92	pushq %fs
93	pushq %gs
94	movl %ds,%r12d
95	movl %es,%r13d
96	movl %ss,%r14d
97	mov %rsp,%r15
98	mov %rcx,%rsi
99	movzwq 0x36(%rsi),%r10 #movzx r10, (IA32_REGS ptr [rsi])._SS
100	xor %rdi,%rdi
101	mov 0xc(%rsi),%edi #mov edi, (IA32_REGS ptr [rsi])._ESP
102	add $0xffffffffffffffb0,%rdi #add rdi, - sizeof (IA32_REGS) - sizeof (_STK16)
103	push %rdi
104	imul $0x10,%r10,%rax
105	add %rax,%rdi
106	pushq $0xe #push sizeof (IA32_REGS) / 4
107	pop %rcx
108	rep movsl %ds:(%rsi),%es:(%rdi)
109	pop %rbx #rbx <- 16-bit stack offset
110	lea Label,%eax #42 <_Thunk16+0x42>
111	stos %eax,%es:(%rdi)
112	movl %cs,%eax #return segment
113	stos %ax,%es:(%rdi)
114	mov %edx,%eax #THUNK Flags
115	stos %ax,%es:(%rdi)
116	sgdt 0x58(%rsp) #save GDTR
117	mov 0x58(%rsp),%rax
118	stos %rax,%es:(%rdi)
119	mov %cr0,%rax #save CR0
120	mov %eax,%esi #esi <- CR0 to set
121	stos %eax,%es:(%rdi)
122	mov %cr4,%rax #save CR4
123	stos %eax,%es:(%rdi)
124	sidt 0x58(%rsp) #save IDTR
125	and $0x7ffffffe,%esi #clear PE & PG bits
126	mov %r10,%rdi #rdi <- 16-bit stack segment
127	shl $0x10,%r8
128	push %r8 #far jmp address
129	lea Label_16Bit,%eax
130	push %rax
131	movw $0x8,0x4(%rsp)
132	lgdt _16Gdtr #bugbug: may not match.
133	lret
134	Label_16Bit:
135	.byte 0x66
136	movl $0xc0000080,%ecx
137	mov %rsi,%cr0 #disable PE & PG
138	rdmsr
139	and $0xfe,%ah
140	wrmsr #clear LME bit
141	mov %cr4,%rax
142	and $0xcf,%al #clear PAE & PSE
143	mov %rax,%cr4
144	lret
145
146	Label:
147	xor %rax,%rax
148	movl %ss,%eax
149	shl $0x4,%eax
150	add %esp,%eax
151	mov %r15,%rsp
152	lidt 0x58(%rsp)
153	movl %r12d,%ds
154	movl %r13d,%es
155	movl %r14d,%ss
156	popq %gs
157	popq %fs
158	pop %r15
159	pop %r14
160	pop %r13
161	pop %r12
162	pop %rdi
163	pop %rsi
164	pop %rbx
165	pop %rbp
166	retq
167
168
169	.align 0x10
170
171	_Code16Addr:
172	ASM_PFX(RealMode):
173	movl %edi,%ss
174	mov %bx,%sp #set up 16-bit stack
175	.byte 0x2e
176	.byte 0x0f
177	.byte 0x01
178	.byte 0x1e\r
179	.word _16Idtr - _Code16Addr #lidt _16Idtr\r
180	.byte 0x66
181	.byte 0x61 #popad\r
182	.byte 0x1f #pop ds\r
183	.byte 0x07 #pop es
184	popq %fs\r
185	popq %gs\r
186	add $0x8,%esp #skip RFLAGS\r
187	.byte 0x67 #test [esp + 0eh], 1
188	.byte 0xf7
189	.byte 0x44
190	.byte 0x24
191	.byte 0x0e
192	.byte 0x01
193	.byte 0x00
194	jz 1f
195	pushfq #pushf, actually
196	1:
197	.byte 0x0e #push cs
198	.byte 0x68 #push /iw
199	.word FarCallRet - _Code16Addr
200	jz 2f
201	.byte 0x66
202	ljmp *6(%esp)
203	2:
204	.byte 0x66
205	ljmp *4(%esp)
206	FarCallRet:
207	.byte 0x66
208	push $0x00 #push a dword of zero
209	.byte 0x66
210	pushf #pushfd, actually
211	pushq %gs
212	pushq %fs
213	.byte 0x06 #push %es
214	.byte 0x1e #push %ds
215	.byte 0x66
216	.byte 0x60
217	cli
218	.byte 0x66 #sizeof (IA32_REGS) = 13 * 4 = 52
219	lgdt 64(%esp) #lgdt (_STK16 ptr [esp + sizeof (IA32_REGS)]).SavedGdtr
220	.byte 0x66
221	mov 76(%esp), %eax
222	mov %rax, %cr4
223	.byte 0x66
224	mov $0xc0000080, %ecx
225	rdmsr
226	orb $1, %ah
227	wrmsr
228	.byte 0x66
229	mov 72(%esp), %eax
230	mov %rax, %cr0 #restore CR0
231	.byte 0x66
232	ljmpl *52(%esp)
233
234	_16Idtr:
235	.word 0x3ff #FWORD (1 SHL 10) - 1
236	.byte 0x00