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Diffstat (limited to 'src/VBox/ValidationKit/bootsectors/bootsector-pae.asm')
-rw-r--r--src/VBox/ValidationKit/bootsectors/bootsector-pae.asm175
1 files changed, 175 insertions, 0 deletions
diff --git a/src/VBox/ValidationKit/bootsectors/bootsector-pae.asm b/src/VBox/ValidationKit/bootsectors/bootsector-pae.asm
new file mode 100644
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+++ b/src/VBox/ValidationKit/bootsectors/bootsector-pae.asm
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+; $Id: bootsector-pae.asm $
+;; @file
+; Bootsector that switches the CPU info PAE mode.
+;
+
+;
+; Copyright (C) 2007-2023 Oracle and/or its affiliates.
+;
+; This file is part of VirtualBox base platform packages, as
+; available from https://www.virtualbox.org.
+;
+; This program is free software; you can redistribute it and/or
+; modify it under the terms of the GNU General Public License
+; as published by the Free Software Foundation, in version 3 of the
+; License.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+; General Public License for more details.
+;
+; You should have received a copy of the GNU General Public License
+; along with this program; if not, see <https://www.gnu.org/licenses>.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+; in the VirtualBox distribution, in which case the provisions of the
+; CDDL are applicable instead of those of the GPL.
+;
+; You may elect to license modified versions of this file under the
+; terms and conditions of either the GPL or the CDDL or both.
+;
+; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+;
+
+%include "iprt/asmdefs.mac"
+%include "iprt/x86.mac"
+%include "VBox/bios.mac"
+
+
+;; The boot sector load address.
+%define BS_ADDR 0x7c00
+%define PDP_ADDR 0x9000
+%define PD_ADDR 0xa000
+
+
+BITS 16
+start:
+ ; Start with a jump just to follow the convention.
+ jmp short the_code
+ nop
+times 3ah db 0
+
+the_code:
+ cli
+ xor edx, edx
+ mov ds, dx ; Use 0 based addresses
+
+ ;
+ ; Create a paging hierarchy
+ ;
+ mov cx, 4
+ xor esi, esi ; physical address
+ mov ebx, PDP_ADDR
+ mov edi, PD_ADDR
+pdptr_loop:
+ ; The page directory pointer entry.
+ mov dword [ebx], edi
+ or word [bx], X86_PDPE_P
+ mov dword [ebx + 4], edx
+
+ ; The page directory.
+pd_loop:
+ mov dword [edi], esi
+ or word [di], X86_PDE4M_P | X86_PDE4M_RW | X86_PDE4M_PS
+ mov dword [edi + 4], 0
+ add esi, 0x00200000 ; 2MB
+ add di, 8
+ test di, 0fffh
+ jnz pd_loop
+
+ add bx, 8
+ loop pdptr_loop
+
+ ;
+ ; Switch to protected mode.
+ ;
+ lgdt [(gdtr - start) + BS_ADDR]
+ lidt [(idtr_null - start) + BS_ADDR]
+
+ mov eax, PDP_ADDR
+ mov cr3, eax
+
+ mov eax, cr4
+ or eax, X86_CR4_PAE | X86_CR4_PSE
+ mov cr4, eax
+
+ mov eax, cr0
+ or eax, X86_CR0_PE | X86_CR0_PG
+ mov cr0, eax
+ jmp far 0x0008:((code32_start - start) + BS_ADDR) ; 8=32-bit CS
+
+BITS 32
+code32_start:
+ mov ax, 0x10
+ mov ds, ax
+ mov es, ax
+ mov fs, ax
+ mov gs, ax
+ mov ax, 0x18
+ mov es, ax
+ mov esp, 0x80000
+
+ ; eye catchers
+ mov eax, 0xCafeBabe
+ mov ebx, eax
+ mov ecx, eax
+ mov edx, eax
+ mov edi, eax
+ mov esi, eax
+ mov ebp, eax
+
+ ;
+ ; Boch shutdown request.
+ ;
+ mov bl, 64
+ mov dx, VBOX_BIOS_SHUTDOWN_PORT
+ mov ax, VBOX_BIOS_OLD_SHUTDOWN_PORT
+retry:
+ mov ecx, 8
+ mov esi, (szShutdown - start) + BS_ADDR
+ rep outsb
+ xchg dx, ax ; alternate between the new (VBox) and old (Bochs) ports.
+ dec bl
+ jnz retry
+ ; Shutdown failed!
+hlt_again:
+ hlt
+ cli
+ jmp hlt_again
+
+ ;
+ ; The GDT.
+ ;
+align 8, db 0
+gdt:
+ dw 0, 0, 0, 0 ; null selector
+ dw 0xffff, 0, 0x9b00, 0x00cf ; 32 bit flat code segment (0x08)
+ dw 0xffff, 0, 0x9300, 0x00cf ; 32 bit flat data segment (0x10)
+ dw 0xffff, 0, 0x9300, 0x00cf ; 32 bit flat stack segment (0x18)
+
+gdtr:
+ dw 8*4-1 ; limit 15:00
+ dw (gdt - start) + BS_ADDR ; base 15:00
+ db 0 ; base 23:16
+ db 0 ; unused
+
+idtr_null:
+ dw 0 ; limit 15:00
+ dw (gdt - start) + BS_ADDR ; base 15:00
+ db 0 ; base 23:16
+ db 0 ; unused
+
+szShutdown:
+ db 'Shutdown', 0
+
+ ;
+ ; Padd the remainder of the sector with zeros and
+ ; end it with the dos signature.
+ ;
+padding:
+times 510 - (padding - start) db 0
+ db 055h, 0aah
+