;;

;; Copyright (C) 2006-2012 Oracle Corporation

;;

;; This file is part of VirtualBox Open Source Edition (OSE), as

;; available from http://www.virtualbox.org. This file is free software;

;; you can redistribute it and/or modify it under the terms of the GNU

;; General Public License (GPL) as published by the Free Software

;; Foundation, in version 2 as it comes in the "COPYING" file of the

;; VirtualBox OSE distribution. VirtualBox OSE is distributed in the

;; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.

;;

;; --------------------------------------------------------------------

; BIOS32 service directory and 32-bit PCI BIOS entry point

; Public symbols for debugging only

public pcibios32_entry

public bios32_service

; The BIOS32 service directory header must be located in the E0000h-FFFF0h

; range on a paragraph boundary. Note that the actual 32-bit code need not

; be located below 1MB at all.

_DATA segment public 'DATA'

align 16

bios32_directory:

db '_32_' ; ASCII signature

dw bios32_service ; Entry point address...

dw 000Fh ; ...hardcoded to F000 segment

db 0 ; Revision

db 1 ; Length in paras - must be 1

db 0 ; Checksum calculated later

db 5 dup(0) ; Unused, must be zero

_DATA ends

.386

extrn _pci32_function:near

BIOS32 segment public 'CODE' use32

;

; The BIOS32 Service Directory - must be less than 4K in size (easy!).

;

bios32_service proc far

pushfd

cmp bl, 0 ; Only function 0 supported

jnz b32_bad_func

cmp eax, 'ICP$' ; "$PCI"

mov al, 80h ; Unknown service

jnz b32_done

mov ebx, 000f0000h ; Base address (linear)

mov ecx, 0f000h ; Length of service

mov edx, pcibios32_entry ; Entry point offset from base

xor al, al ; Indicate success

b32_done:

popfd

retf

b32_bad_func:

mov al, 81h ; Unsupported function

jmp b32_done

bios32_service endp

;

; The 32-bit PCI BIOS entry point - simply calls into C code.

;

pcibios32_entry proc far

pushfd ; Preserve flags

cld ; Just in case...

push es ; Call into C implementation

pushad

call _pci32_function

popad

pop es

popfd ; Restore flags and return

retf

pcibios32_entry endp

BIOS32 ends

end