; Project name : XTIDE Universal BIOS ; Description : Defines for BOOTVARS struct used by boot menu ; and drive initialization. ; ; XTIDE Universal BIOS and Associated Tools ; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 by XTIDE Universal BIOS Team. ; ; 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; either version 2 of the License, or ; (at your option) any later version. ; ; 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. ; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html ; %ifndef BOOTVARS_INC %define BOOTVARS_INC ; Temporary locations for system interrupt handlers. Stored during ROM initialization ; and needed when we do full initialization and drive detection on INT 19h TEMPORARY_VECTOR_FOR_SYSTEM_INT13h EQU 32h ; Unused by BIOS (reserved for DOS) TEMPORARY_VECTOR_FOR_SYSTEM_INT19h EQU 33h ; Unused by BIOS (reserved for DOS) ; Default drives DEFAULT_FLOPPY_DRIVE_LETTER EQU 'A' DEFAULT_HARD_DRIVE_LETTER EQU 'C' ; Number of times to retry booting before accepting error BOOT_READ_RETRY_TIMES EQU 3 %ifdef MODULE_HOTKEYS struc HOTKEYVARS .fpPrevTimerHandler resb 4 ; Previous 1Ch timer handler .wTimeWhenDisplayed resb 2 ; System time (ticks) when Hotkey bar was first displayed .wFddAndHddLetters: .bFddLetter resb 1 ; Floppy Drive letter hotkey (upper case) .wHddLetterAndFlags: .bHddLetter resb 1 ; Hard Drive letter hotkey (upper case). Must be after .bFddLetter! .bFlags resb 1 ; Must be just after .bHddLetter! (dependency in Hotkeybar.asm) .bScancode resb 1 ; Function hotkey scancode, must be just after .bFlags! endstruc %ifndef CHECK_FOR_UNUSED_ENTRYPOINTS %if HOTKEYVARS.bFddLetter+1 != HOTKEYVARS.bHddLetter || HOTKEYVARS.bHddLetter+1 != HOTKEYVARS.bFlags || HOTKEYVARS.bFlags+1 != HOTKEYVARS.bScancode %error "HOTKEYVARS: bytes need to come in the order .bFddLetter, then .bHddLetter, then .bFlags, then .bScancode" %endif %endif ; Bit defines for HOTKEYVARS.bFlags FLG_HOTKEY_HD_FIRST EQU (1<<0) ; First try to boot from HDD, then FDD %endif ; MODULE_HOTKEYS ; Pre-boot variables. These do not exist after successful boot to OS. ; Segment is always 0000h, same as BDA segment struc BOOTVARS resb 7C00h .rgbAtaInfo: ; 7C00h, ATA Information for drive detection .rgbBootSect resb 512 ; 7C00h, Boot sector resb 256 ; Boot Menu stack .rgbMnuStack: .dwPostStack resb 4 ; POST stack pointer when entering INT 19h %ifdef MODULE_HOTKEYS .hotkeyVars resb HOTKEYVARS_size ; Must be located just before DRVDETECTINFO structs %endif .rgDrvDetectInfo: ; Array containing DRVDETECTINFO structs endstruc ; MAX_HARD_DISK_NAME_LENGTH must be defined ahead of the DRVDETECTINFO structure to avoid problems with NASM MAX_HARD_DISK_NAME_LENGTH EQU 30 ; Bytes reserved for drive name struc DRVDETECTINFO .StartOfDrvDetectInfo: .szDrvName resb MAX_HARD_DISK_NAME_LENGTH resb 2 ; Zero word (ensures string terminates) .wInitErrorFlags resb 2 ; Errors during initialization ; DRVDETECTINFO's size must be an even multiple of DPT's size .EndOfDriveDetectInfo: resb LARGEST_DPT_SIZE - (.EndOfDriveDetectInfo % LARGEST_DPT_SIZE) endstruc DPT_DRVDETECTINFO_SIZE_MULTIPLIER EQU DRVDETECTINFO_size / LARGEST_DPT_SIZE %ifndef CHECK_FOR_UNUSED_ENTRYPOINTS %if MAX_HARD_DISK_NAME_LENGTH % 2 <> 0 %error "MAX_HARD_DISK_NAME_LENGTH needs to be a multiple of 2, memory is moved with word operations." %endif %endif ;-------------------------------------------------------------------- ; Stores POST stack pointer to BOOTVARS. ; ; STORE_POST_STACK_POINTER ; Parameters: ; ES: BDA and Interrupt Vector segment (zero) ; Returns: ; Nothing ; Corrupts registers: ; Nothing ;-------------------------------------------------------------------- %macro STORE_POST_STACK_POINTER 0 mov [es:BOOTVARS.dwPostStack], sp mov [es:BOOTVARS.dwPostStack+2], ss %endmacro ;-------------------------------------------------------------------- ; Initializes stack for boot menu usage. ; POST stack is not large enough when DPTs are stored to 30:0h. ; ; Note regarding LOAD_BDA_SEGMENT_TO: If you force the use of SP ; then you also have to unconditionally enable the CLI/STI pair. ; The reason for this is that only some buggy 808x CPU:s need the ; CLI/STI instruction pair when changing stacks. Other CPU:s disable ; interrupts automatically when SS is modified for the duration of ; the immediately following instruction to give time to change SP. ; ; SWITCH_TO_BOOT_MENU_STACK ; Parameters: ; Nothing ; Returns: ; SS:SP: Pointer to top of Boot Menu stack ; Corrupts registers: ; Nothing ;-------------------------------------------------------------------- %macro SWITCH_TO_BOOT_MENU_STACK 0 %ifndef USE_186 cli ; Disable interrupts %endif LOAD_BDA_SEGMENT_TO ss, sp mov sp, BOOTVARS.rgbMnuStack ; Load offset to stack %ifndef USE_186 sti ; Enable interrupts %endif %endmacro ;-------------------------------------------------------------------- ; Restores SS and SP to initial boot loader values. ; ; Note! Must return with AX=0 and CF preserved. ; See Int19hMenu_JumpToBootSector_or_RomBoot. ; ; SWITCH_BACK_TO_POST_STACK ; Parameters: ; AX: BDA and Interrupt Vector segment (zero) ; Returns: ; SS:SP: Ptr to POST stack ; Corrupts registers: ; Nothing (not even FLAGS) ;-------------------------------------------------------------------- %macro SWITCH_BACK_TO_POST_STACK 0 %ifndef USE_386 cli mov ss, ax mov sp, [ss:BOOTVARS.dwPostStack] mov ss, [ss:BOOTVARS.dwPostStack+2] sti %else mov ss, ax lss sp, [ss:BOOTVARS.dwPostStack] %endif %endmacro %endif ; BOOTVARS_INC