VirtualBox

source: vbox/trunk/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-mode-SwitchToPP32.asm@ 66289

Last change on this file since 66289 was 64694, checked in by vboxsync, 8 years ago

bs3kit: Added Bs3SwitchTo32BitAndCallC and fixed a few problems switching from PE32 to other mode and back again.

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File size: 5.8 KB
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1; $Id: bs3-mode-SwitchToPP32.asm 64694 2016-11-17 17:10:47Z vboxsync $
2;; @file
3; BS3Kit - Bs3SwitchToPP32
4;
5
6;
7; Copyright (C) 2007-2016 Oracle Corporation
8;
9; This file is part of VirtualBox Open Source Edition (OSE), as
10; available from http://www.virtualbox.org. This file is free software;
11; you can redistribute it and/or modify it under the terms of the GNU
12; General Public License (GPL) as published by the Free Software
13; Foundation, in version 2 as it comes in the "COPYING" file of the
14; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16;
17; The contents of this file may alternatively be used under the terms
18; of the Common Development and Distribution License Version 1.0
19; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20; VirtualBox OSE distribution, in which case the provisions of the
21; CDDL are applicable instead of those of the GPL.
22;
23; You may elect to license modified versions of this file under the
24; terms and conditions of either the GPL or the CDDL or both.
25;
26
27%include "bs3kit-template-header.mac"
28
29
30;;
31; Switch to 32-bit paged protected mode from any other mode.
32;
33; @cproto BS3_DECL(void) Bs3SwitchToPE32(void);
34;
35; @uses Nothing (except high 32-bit register parts), upper part of ESP is
36; cleared if caller is in 16-bit mode.
37;
38; @remarks Obviously returns to 32-bit mode, even if the caller was
39; in 16-bit or 64-bit mode. It doesn't not preserve the callers
40; ring, but instead changes to ring-0.
41;
42; @remarks Does not require 20h of parameter scratch space in 64-bit mode.
43;
44BS3_GLOBAL_NAME_EX TMPL_NM(Bs3SwitchToPP32_Safe), function, 0
45BS3_PROC_BEGIN_MODE Bs3SwitchToPP32, BS3_PBC_NEAR
46%ifdef TMPL_PP32
47 ret
48
49%elif BS3_MODE_IS_V86(TMPL_MODE)
50 ;
51 ; V8086 - Switch to 16-bit ring-0 and call worker for that mode.
52 ;
53 extern BS3_CMN_NM(Bs3SwitchToRing0)
54 call BS3_CMN_NM(Bs3SwitchToRing0)
55 extern %[BS3_MODE_R0_NM_ %+ TMPL_MODE](Bs3SwitchToPP32)
56 jmp %[BS3_MODE_R0_NM_ %+ TMPL_MODE](Bs3SwitchToPP32)
57
58%else
59 ;
60 ; Switch to real mode.
61 ;
62 %if TMPL_BITS != 32
63 %if TMPL_BITS > 32
64 shl xPRE [xSP], 32 ; Adjust the return address from 64-bit to 32-bit.
65 add rsp, xCB - 4
66 %else
67 push word 0 ; Reserve space to expand the return address.
68 %endif
69 %endif
70 %if TMPL_BITS != 16
71 ; Must be in 16-bit segment when calling Bs3SwitchTo16Bit.
72 jmp .sixteen_bit_segment
73BS3_BEGIN_TEXT16
74 BS3_SET_BITS TMPL_BITS
75BS3_GLOBAL_LOCAL_LABEL .sixteen_bit_segment
76 %endif
77
78 ;
79 ; Switch to real mode.
80 ;
81 extern TMPL_NM(Bs3SwitchToRM)
82 call TMPL_NM(Bs3SwitchToRM)
83 BS3_SET_BITS 16
84
85 push eax
86 push ecx
87 pushfd
88
89 ;
90 ; Make sure PAE is really off and that PSE is on when supported.
91 ;
92BS3_EXTERN_DATA16 g_uBs3CpuDetected
93BS3_BEGIN_TEXT16
94 test byte [1 + BS3_DATA16_WRT(g_uBs3CpuDetected)], (BS3CPU_F_CPUID >> 8)
95 jz .cr4_is_fine
96 mov eax, cr4
97 mov ecx, eax
98 and eax, ~(X86_CR4_PAE | X86_CR4_PSE)
99 test byte [1 + BS3_DATA16_WRT(g_uBs3CpuDetected)], (BS3CPU_F_PSE >> 8)
100 jz .no_pse
101 or eax, X86_CR4_PSE
102.no_pse:
103 cmp eax, ecx
104 je .cr4_is_fine
105 mov cr4, eax
106.cr4_is_fine:
107
108 ;
109 ; Get the page directory (returned in eax).
110 ; Will lazy init page tables (in 16-bit prot mode).
111 ;
112 extern NAME(Bs3PagingGetRootForPP32_rm)
113 call NAME(Bs3PagingGetRootForPP32_rm)
114
115 cli
116 mov cr3, eax
117
118 ;
119 ; Load the GDT and enable PE32.
120 ;
121BS3_EXTERN_SYSTEM16 Bs3LgdtDef_Gdt
122BS3_EXTERN_SYSTEM16 Bs3Lgdt_Gdt
123BS3_BEGIN_TEXT16
124 mov ax, BS3SYSTEM16
125 mov ds, ax
126 lgdt [Bs3LgdtDef_Gdt] ; Will only load 24-bit base!
127
128 mov eax, cr0
129 or eax, X86_CR0_PE | X86_CR0_PG
130 mov cr0, eax
131 jmp BS3_SEL_R0_CS32:dword .thirty_two_bit wrt FLAT
132BS3_BEGIN_TEXT32
133BS3_GLOBAL_LOCAL_LABEL .thirty_two_bit
134 ;
135 ; Convert the (now) real mode stack pointer to 32-bit flat.
136 ;
137 xor eax, eax
138 mov ax, ss
139 shl eax, 4
140 and esp, 0ffffh
141 add esp, eax
142
143 mov ax, BS3_SEL_R0_SS32
144 mov ss, ax
145
146 ;
147 ; Call rountine for doing mode specific setups.
148 ;
149 extern NAME(Bs3EnteredMode_pp32)
150 call NAME(Bs3EnteredMode_pp32)
151
152 ; Load full 32-bit GDT base address.
153 lgdt [Bs3Lgdt_Gdt wrt FLAT]
154
155 ;
156 ; Restore ecx, eax and flags (IF).
157 ;
158 %if TMPL_BITS < 32
159 movzx eax, word [esp + 12 + 2] ; Load return address.
160 add eax, BS3_ADDR_BS3TEXT16 ; Convert it to a flat address.
161 mov [esp + 12], eax ; Store it in the place right for 32-bit returns.
162 %endif
163 popfd
164 pop ecx
165 pop eax
166 ret
167
168 %if TMPL_BITS != 32
169TMPL_BEGIN_TEXT
170 %endif
171%endif
172BS3_PROC_END_MODE Bs3SwitchToPP32
173
174
175%if TMPL_BITS == 16
176;;
177; Custom far stub.
178BS3_BEGIN_TEXT16_FARSTUBS
179BS3_PROC_BEGIN_MODE Bs3SwitchToPP32, BS3_PBC_FAR
180 inc bp
181 push bp
182 mov bp, sp
183
184 ; Call the real thing.
185 call TMPL_NM(Bs3SwitchToPP32)
186 BS3_SET_BITS 32
187
188 ; Jmp to common code for the tedious conversion.
189 %if BS3_MODE_IS_RM_OR_V86(TMPL_MODE)
190 extern _Bs3SwitchHlpConvRealModeRetfPopBpDecBpAndReturn_c32
191 jmp _Bs3SwitchHlpConvRealModeRetfPopBpDecBpAndReturn_c32
192 %else
193 extern _Bs3SwitchHlpConvProtModeRetfPopBpDecBpAndReturn_c32
194 jmp _Bs3SwitchHlpConvProtModeRetfPopBpDecBpAndReturn_c32
195 %endif
196 BS3_SET_BITS 16
197BS3_PROC_END_MODE Bs3SwitchToPP32
198%endif
199
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