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|
;------------------------------------------------------------------------------
; @file
; A minimal Int10h stub that allows the Windows 2008 R2 SP1 UEFI guest's buggy,
; default VGA driver to switch to 1024x768x32, on the stdvga and QXL video
; cards of QEMU.
;
; Copyright (C) 2014, Red Hat, Inc.
; Copyright (c) 2013 - 2014, Intel Corporation. All rights reserved.<BR>
;
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
; enable this macro for debug messages
;%define DEBUG
%macro DebugLog 1
%ifdef DEBUG
push si
mov si, %1
call PrintStringSi
pop si
%endif
%endmacro
BITS 16
ORG 0
VbeInfo:
TIMES 256 nop
VbeModeInfo:
TIMES 256 nop
Handler:
cmp ax, 0x4f00
je GetInfo
cmp ax, 0x4f01
je GetModeInfo
cmp ax, 0x4f02
je SetMode
cmp ax, 0x4f03
je GetMode
cmp ax, 0x4f10
je GetPmCapabilities
cmp ax, 0x4f15
je ReadEdid
cmp ah, 0x00
je SetModeLegacy
DebugLog StrUnknownFunction
Hang:
jmp Hang
GetInfo:
push es
push di
push ds
push si
push cx
DebugLog StrEnterGetInfo
; target (es:di) set on input
push cs
pop ds
mov si, VbeInfo
; source (ds:si) set now
mov cx, 256
cld
rep movsb
pop cx
pop si
pop ds
pop di
pop es
jmp Success
GetModeInfo:
push es
push di
push ds
push si
push cx
DebugLog StrEnterGetModeInfo
and cx, ~0x4000 ; clear potentially set LFB bit in mode number
cmp cx, 0x00f1
je KnownMode1
DebugLog StrUnknownMode
jmp Hang
KnownMode1:
; target (es:di) set on input
push cs
pop ds
mov si, VbeModeInfo
; source (ds:si) set now
mov cx, 256
cld
rep movsb
pop cx
pop si
pop ds
pop di
pop es
jmp Success
%define ATT_ADDRESS_REGISTER 0x03c0
%define VBE_DISPI_IOPORT_INDEX 0x01ce
%define VBE_DISPI_IOPORT_DATA 0x01d0
%define VBE_DISPI_INDEX_XRES 0x1
%define VBE_DISPI_INDEX_YRES 0x2
%define VBE_DISPI_INDEX_BPP 0x3
%define VBE_DISPI_INDEX_ENABLE 0x4
%define VBE_DISPI_INDEX_BANK 0x5
%define VBE_DISPI_INDEX_VIRT_WIDTH 0x6
%define VBE_DISPI_INDEX_VIRT_HEIGHT 0x7
%define VBE_DISPI_INDEX_X_OFFSET 0x8
%define VBE_DISPI_INDEX_Y_OFFSET 0x9
%define VBE_DISPI_ENABLED 0x01
%define VBE_DISPI_LFB_ENABLED 0x40
%macro BochsWrite 2
push dx
push ax
mov dx, VBE_DISPI_IOPORT_INDEX
mov ax, %1
out dx, ax
mov dx, VBE_DISPI_IOPORT_DATA
mov ax, %2
out dx, ax
pop ax
pop dx
%endmacro
SetMode:
push dx
push ax
DebugLog StrEnterSetMode
cmp bx, 0x40f1
je KnownMode2
DebugLog StrUnknownMode
jmp Hang
KnownMode2:
; unblank
mov dx, ATT_ADDRESS_REGISTER
mov al, 0x20
out dx, al
BochsWrite VBE_DISPI_INDEX_ENABLE, 0
BochsWrite VBE_DISPI_INDEX_BANK, 0
BochsWrite VBE_DISPI_INDEX_X_OFFSET, 0
BochsWrite VBE_DISPI_INDEX_Y_OFFSET, 0
BochsWrite VBE_DISPI_INDEX_BPP, 32
BochsWrite VBE_DISPI_INDEX_XRES, 1024
BochsWrite VBE_DISPI_INDEX_VIRT_WIDTH, 1024
BochsWrite VBE_DISPI_INDEX_YRES, 768
BochsWrite VBE_DISPI_INDEX_VIRT_HEIGHT, 768
BochsWrite VBE_DISPI_INDEX_ENABLE, VBE_DISPI_ENABLED | VBE_DISPI_LFB_ENABLED
pop ax
pop dx
jmp Success
GetMode:
DebugLog StrEnterGetMode
mov bx, 0x40f1
jmp Success
GetPmCapabilities:
DebugLog StrGetPmCapabilities
jmp Unsupported
ReadEdid:
DebugLog StrReadEdid
jmp Unsupported
SetModeLegacy:
DebugLog StrEnterSetModeLegacy
cmp al, 0x03
je KnownMode3
cmp al, 0x12
je KnownMode4
DebugLog StrUnknownMode
jmp Hang
KnownMode3:
mov al, 0x30
jmp SetModeLegacyDone
KnownMode4:
mov al, 0x20
SetModeLegacyDone:
DebugLog StrExitSuccess
iret
Success:
DebugLog StrExitSuccess
mov ax, 0x004f
iret
Unsupported:
DebugLog StrExitUnsupported
mov ax, 0x014f
iret
%ifdef DEBUG
PrintStringSi:
pusha
push ds ; save original
push cs
pop ds
mov dx, 0x0402
PrintStringSiLoop:
lodsb
cmp al, 0
je PrintStringSiDone
out dx, al
jmp PrintStringSiLoop
PrintStringSiDone:
pop ds ; restore original
popa
ret
StrExitSuccess:
db 'Exit', 0x0a, 0
StrExitUnsupported:
db 'Unsupported', 0x0a, 0
StrUnknownFunction:
db 'Unknown Function', 0x0a, 0
StrEnterGetInfo:
db 'GetInfo', 0x0a, 0
StrEnterGetModeInfo:
db 'GetModeInfo', 0x0a, 0
StrEnterGetMode:
db 'GetMode', 0x0a, 0
StrEnterSetMode:
db 'SetMode', 0x0a, 0
StrEnterSetModeLegacy:
db 'SetModeLegacy', 0x0a, 0
StrUnknownMode:
db 'Unknown Mode', 0x0a, 0
StrGetPmCapabilities:
db 'GetPmCapabilities', 0x0a, 0
StrReadEdid:
db 'ReadEdid', 0x0a, 0
%endif
|
