writembr: Implement support for GPT partitions, #4028.
* This should support both GPT and MBR formatted partitions. * To boot Haiku from a GPT partition, it must have the correct BFS UUID for the partition. * Tools such as gdisk/gptfdisk can create partitions with the correct BFS UUID.
This commit is contained in:
Jessica Hamilton
@@ -134,3 +134,16 @@ actions BootStaticLibraryObjects
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$(RM) "$(1)"
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$(RM) "$(1)"
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$(HAIKU_AR_$(TARGET_PACKAGING_ARCH)) -r "$(1)" "$(2)" ;
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$(HAIKU_AR_$(TARGET_PACKAGING_ARCH)) -r "$(1)" "$(2)" ;
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}
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}
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rule BuildMBR binary : source
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{
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SEARCH on $(source) = $(SUBDIR) ;
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MakeLocateDebug $(binary) ;
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Depends $(binary) : $(source) ;
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}
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actions BuildMBR
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{
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$(RM) $(1)
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$(HAIKU_CC_$(HAIKU_PACKAGING_ARCH)) $(2) -o $(1) $(MBRFLAGS) -nostdlib -Xlinker --oformat=binary -Xlinker -S -Xlinker -N -Xlinker "-e start" -Xlinker "-Ttext=0x600"
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}
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@@ -4,19 +4,6 @@ HAIKU_ANYBOOT_DIR ?= $(HAIKU_DEFAULT_ANYBOOT_DIR) ;
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HAIKU_ANYBOOT = $(HAIKU_ANYBOOT_NAME) ;
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HAIKU_ANYBOOT = $(HAIKU_ANYBOOT_NAME) ;
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HAIKU_ANYBOOT_LABEL ?= $(HAIKU_DEFAULT_ANYBOOT_LABEL) ;
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HAIKU_ANYBOOT_LABEL ?= $(HAIKU_DEFAULT_ANYBOOT_LABEL) ;
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rule BuildAnybootMBR binary : source {
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Depends $(binary) : $(source) ;
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MBR_SOURCE on $(binary) = $(source) ;
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BuildAnybootMBR1 $(binary) ;
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}
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actions BuildAnybootMBR1 {
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$(RM) $(1)
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$(HAIKU_NASM) -f bin $(MBR_SOURCE) -O5 -o $(1)
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}
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rule BuildAnybootImage anybootImage : mbrPart : isoPart : imageFile {
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rule BuildAnybootImage anybootImage : mbrPart : isoPart : imageFile {
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local anyboot = <build>anyboot ;
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local anyboot = <build>anyboot ;
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@@ -33,8 +20,8 @@ actions BuildAnybootImage1 {
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}
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}
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local baseMBR = base_mbr.bin ;
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local baseMBR = base_mbr.bin ;
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local mbrSource = [ FDirName $(HAIKU_TOP) src bin writembr mbr.nasm ] ;
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local mbrSource = [ FDirName $(HAIKU_TOP) src bin writembr mbr.S ] ;
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BuildAnybootMBR $(baseMBR) : $(mbrSource) ;
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BuildMBR $(baseMBR) : $(mbrSource) ;
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MakeLocate $(baseMBR) : $(HAIKU_OUTPUT_DIR) ;
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MakeLocate $(baseMBR) : $(HAIKU_OUTPUT_DIR) ;
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MakeLocate $(HAIKU_ANYBOOT) : $(HAIKU_ANYBOOT_DIR) ;
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MakeLocate $(HAIKU_ANYBOOT) : $(HAIKU_ANYBOOT_DIR) ;
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BuildAnybootImage $(HAIKU_ANYBOOT) : $(baseMBR) : $(HAIKU_CD_BOOT_IMAGE)
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BuildAnybootImage $(HAIKU_ANYBOOT) : $(baseMBR) : $(HAIKU_CD_BOOT_IMAGE)
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@@ -4,12 +4,8 @@ UsePrivateHeaders kernel shared storage ;
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UsePrivateSystemHeaders ;
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UsePrivateSystemHeaders ;
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# Assemble the MBR code, and convert it into a header file
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# Assemble the MBR code, and convert it into a header file
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MBRFLAGS on [ FGristFiles mbr.bin ] = -DMBR_CODE_ONLY ;
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NASMFLAGS on [ FGristFiles mbr.bin ] = -f bin -O5 -dMBR_CODE_ONLY=1 ;
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BuildMBR [ FGristFiles mbr.bin ] : mbr.S ;
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SEARCH on mbr.nasm = [ FDirName $(HAIKU_TOP) src bin writembr ] ;
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Object [ FGristFiles mbr.bin ] : mbr.nasm ;
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DataFileToSourceFile [ FGristFiles MBR.h ] : [ FGristFiles mbr.bin ]
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DataFileToSourceFile [ FGristFiles MBR.h ] : [ FGristFiles mbr.bin ]
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: kMBR : kMBRSize ;
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: kMBR : kMBRSize ;
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@@ -9,10 +9,7 @@ Application writembr :
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;
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;
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# Assemble the MBR code, and convert it into a header file
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# Assemble the MBR code, and convert it into a header file
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BuildMBR [ FGristFiles mbr.bin ] : mbr.S ;
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NASMFLAGS on [ FGristFiles mbr.bin ] = -f bin -O5 ;
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Object [ FGristFiles mbr.bin ] : mbr.nasm ;
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DataFileToSourceFile [ FGristFiles MBR.h ] : [ FGristFiles mbr.bin ]
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DataFileToSourceFile [ FGristFiles MBR.h ] : [ FGristFiles mbr.bin ]
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: kMBR : kMBRSize ;
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: kMBR : kMBRSize ;
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@@ -0,0 +1,464 @@
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/*
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* Partly from:
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* $FreeBSD: src/sys/boot/i386/pmbr/pmbr.s,v 1.2 2007/11/26 21:29:59 jhb Exp $
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*
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* Copyright (c) 2007 Yahoo!, Inc.
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* All rights reserved.
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* Written by: John Baldwin <jhb@FreeBSD.org>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the names of any co-contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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*
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* Partly from:
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* $FreeBSD: src/sys/boot/i386/mbr/mbr.s,v 1.7 2004/08/28 08:39:35 yar Exp $
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*
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* Copyright (c) 1999 Robert Nordier
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are freely
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* permitted provided that the above copyright notice and this
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* paragraph and the following disclaimer are duplicated in all
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* such forms.
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*
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* This software is provided "AS IS" and without any express or
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* implied warranties, including, without limitation, the implied
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* warranties of merchantability and fitness for a particular
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* purpose.
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*
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*
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* "Hybridisation" and modifications for booting Haiku by Andre' Braga
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* (me@andrebraga.com), with valuable input from Jean-Loïc Charroud
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* (jcharroud@free.fr). The modifications contained herein are released into
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* the Public Domain.
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*
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*
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* A 432 bytes MBR IPL (Initial Program Loader) that looks for the UUID of
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* a Haiku Boot GUID partition and boots it, falling back to MBR partitions if
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* said UUID isn't found or if the (primary) GPT is corrupted or non-existent.
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* Its usefulness is in being a versatile, "universal" IPL that supports
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* both partitioning styles, allowing it to be used transparently and even
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* facilitating the conversion between partitioning styles, should the need
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* for more partitions or volumes over 2TiB arise (for instance when cloning
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* an older disk to a newer, more capacious one).
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* It also paves the way for Haiku to create and support booting from
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* multiple volumes larger than 2TiB, which we're in the very privileged
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* position of enjoying efficiently in the near future due to BFS. Another use
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* case is taking a disk from a Intel EFI machine, plugging it on a BIOS
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* machine and boot just fine; and vice-versa.
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* As mentioned, if there are valid partitions defined in the MBR, and the
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* primary GPT becomes corrupt, it can fall back to loading the MBR partition
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* with the active flag set, if one is defined.
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* Currently there's no provision for falling back to the GPT copy that
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* lives in the end of the disk, due to the 512 bytes constraint; supporting
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* this is unlikely given that the code is packed tight. An alternative would be
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* disabling support for booting from MBR using BIOS calls other than Int13h
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* function 42h, "Extended Read From Disk" (i.e., LBA mode). It's unlikely that
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* any machine that Haiku supports won't have this BIOS function, but having an
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* "universal" IPL should be quite useful to, say, people using Haiku to
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* rewrite a corrupt MBR on another disk using the excellent DiskProbe.
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* The number of sectors loaded depends on the boot style. Booting from a
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* MBR partition assumes that the Partition Boot Record is one sector long,
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* whereas booting from a GPT partition assumes a partition exclusive for a
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* system loader and will either copy its entirety into memory starting from
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* address 0x7c00, or will copy up to circa 545KiB, whichever is smaller. Thus,
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* it remains compatible with the FreeBSD gptloader and should work for loading
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* Bootman from an exclusive Haiku boot manager partition as well.
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* It should be easy to adjust the UUID signature as needed. It lives at
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* offset 0x1a0 (416), leaving plenty of space before the 32-bit disk signature
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* at offset 0x1b8 (440), so compatibility with Microsoft Windows and other OSs
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* is maintained.
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*/
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.set LOAD,0x7c00
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.set EXEC,0x600
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.set MAGIC,0xaa55
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.set HANDSHAKE,0x55aa
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.set SECSIZE,0x200
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/* data offsets */
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.set UUID,0x1a0
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.set DISKSIG,0x1b8
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.set PT_OFF,0x1be
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.set GPTSTACK,EXEC+SECSIZE*4-8 /* Stack address */
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.set LBABUF,GPTSTACK /* LBA address pointer buffer, */
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/* 8 bytes long, after stack */
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.set GPT_ADDR,LBABUF+8 /* GPT header address */
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.set GPT_SIG,0 /* Signature offset from LBA 1 */
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.set GPT_SIG_0,0x20494645 /* "EFI ", bswapped */
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.set GPT_SIG_1,0x54524150 /* "PART", bswapped */
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.set GPT_MYLBA,24 /* Offs of curr header copy addr */
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.set GPT_PART_LBA,72 /* Offs of partitions start LBA */
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.set GPT_NPART,80 /* Offs to number of partitions */
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.set GPT_PART_SIZE,84 /* Offs to size of partition */
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.set PART_ADDR,GPT_ADDR+SECSIZE /* GPT partition array addr. */
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.set PART_TYPE,0
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.set PART_START_LBA,32 /* Offs to 1st LBA on part entry */
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.set PART_END_LBA,40 /* Offs to last LBA */
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.set NHRDRV,0x475 /* Number of hard drives */
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.globl start /* Entry point */
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.code16
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/*
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* Setup the segment registers for flat addressing and setup the stack.
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*/
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start: cli /* Clear interrupts before relocation */
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xorw %ax,%ax /* Zero */
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movw %ax,%es /* Address */
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movw %ax,%ds /* data */
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movw %ax,%ss /* Set up */
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movw $GPTSTACK,%sp /* stack */
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std /* String ops set to decrement */
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movw $LOAD,%si /* We'll clear working memory starting */
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leaw -1(%si),%di /* from $LOAD-1 and stopping at EXEC. */
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movw $(LOAD-EXEC-1),%cx /* In the end we have %si pointing */
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rep stosb /* at LOAD and %di at EXEC. */
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/*
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* Relocate ourself to a lower address so that we have more room to load
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* other sectors.
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*/
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reloc: cld /* String ops set to increment */
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movw $SECSIZE,%cx /* Now we walk forward and relocate. */
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rep movsb /* Tricky, but works great! */
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/*
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* Jump to the relocated code.
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*/
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jmp $0,$main /* Absolute address (far) jump */
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/*
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* Will land here; we're now at %cs = 0x0000 and %ip a little above 0x0600
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*/
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main: sti /* Re-enable interrupts */
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#ifdef VALIDATE_DRV
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/*
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* Validate drive number in %dl. Certain BIOSes might not like it.
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*/
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validate_drv:
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cmpb $0x80,%dl /* Drive valid? (>= 0x80) */
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jb validate_drv.1 /* No */
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movb NHRDRV,%dh /* Calculate the highest */
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addb $0x80,%dh /* drive number available */
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cmpb %dh,%dl /* Within range? */
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jb test_extensions /* Yes, proceed */
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validate_drv.1:
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movb $0x80,%dl /* Else, assume drive 0x80 */
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#endif
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/*
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* Test if BIOS supports Int13h extensions. If so, will try GPT scheme first.
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* Else, sets flag (%dh = 1) and goes straight to MBR code.
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* (%dl still contains the drive number from BIOS bootstrap)
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*/
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test_extensions:
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movb $0,%dh /* We'll test for EDD extensions. */
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/* LBA read (Int13,42) uses only */
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/* %dl to get drive number and if */
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/* we must fall back to CHS read */
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/* (Int13,02), %dh receives head */
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/* number, so it's clear to use */
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/* %dh to hold a "use CHS" flag */
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movw $HANDSHAKE,%bx /* EDD extensions magic number */
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movb $0x41,%ah /* BIOS: EDD extensions */
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int $0x13 /* present? */
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jc set_chs /* No, fall back to CHS read */
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test_magic:
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cmpw $MAGIC,%bx /* Magic ok? */
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jne set_chs /* No, fall back to CHS read */
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test_packet:
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testb $0x1,%cl /* Packet mode present? */
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jnz load_gpt_hdr /* Yes! */
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set_chs:
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movb $1,%dh /* read_chs overwrites this, and */
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/* Int13,42 only uses %dl, so */
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/* it's clear to use %dh as flag */
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jmp try_mbr
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/*
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* If we reached here, drive is valid, LBA reads are available, will try GPT.
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* Load the primary GPT header from LBA 1 and verify signature.
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*/
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load_gpt_hdr:
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movw $GPT_ADDR,%bx
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movw $LBABUF,%si /* Will load LBA sector 1 from disk */
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movb $1,(%si) /* (64-bit value! Memory was zeroed so */
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/* it's OK to write only the LSB) */
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call read
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cmpl $GPT_SIG_0,GPT_ADDR+GPT_SIG
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jnz try_mbr /* If invalid GPT header */
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cmpl $GPT_SIG_1,GPT_ADDR+GPT_SIG+4
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jnz try_mbr /* Fluke :( Try MBR now */
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/*
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* GPT is valid. Load a partition table sector from disk and look for a
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* partition matching the UUID found in boot_uuid.
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*/
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load_part:
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movw $GPT_ADDR+GPT_PART_LBA,%si
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movw $PART_ADDR,%bx
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call read
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scan:
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movw %bx,%si /* Compare partition UUID */
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movw $boot_uuid,%di /* with Haiku boot UUID */
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movb $0x10,%cl /* (16 bytes) */
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repe cmpsb
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jnz next_part /* Didn't match, next partition */
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/*
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* We found a partition. Load it into RAM starting at 0x7c00.
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*/
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movw %bx,%di /* Save partition pointer in %di */
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leaw PART_START_LBA(%di),%si
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movw $LOAD/16,%bx
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movw %bx,%es
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xorw %bx,%bx
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load_bootcode:
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push %si /* Save %si */
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call read
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pop %si /* Restore */
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||||||
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movl PART_END_LBA(%di),%eax /* See if this was the last LBA */
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||||||
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cmpl (%si),%eax
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||||||
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jnz next_boot_lba
|
||||||
|
movl PART_END_LBA+4(%di),%eax
|
||||||
|
cmpl 4(%si),%eax
|
||||||
|
jnz next_boot_lba
|
||||||
|
jmp start_loader /* Jump to boot code */
|
||||||
|
|
||||||
|
next_boot_lba:
|
||||||
|
incl (%si) /* Next LBA */
|
||||||
|
adcl $0,4(%si)
|
||||||
|
mov %es,%ax /* Adjust segment for next */
|
||||||
|
addw $SECSIZE/16,%ax /* sector */
|
||||||
|
cmp $0x9000,%ax /* Don't load past 0x90000, */
|
||||||
|
jae start_loader /* 545k should be enough for */
|
||||||
|
mov %ax,%es /* any boot code. :) */
|
||||||
|
jmp load_bootcode
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Move to the next partition. If we walk off the end of the sector, load
|
||||||
|
* the next sector.
|
||||||
|
*/
|
||||||
|
next_part:
|
||||||
|
decl GPT_ADDR+GPT_NPART /* Was this the last partition? */
|
||||||
|
jz try_mbr /* UUID boot signature not found */
|
||||||
|
movw GPT_ADDR+GPT_PART_SIZE,%ax
|
||||||
|
addw %ax,%bx /* Next partition */
|
||||||
|
cmpw $PART_ADDR+0x200,%bx /* Still in sector? */
|
||||||
|
jb scan
|
||||||
|
incl GPT_ADDR+GPT_PART_LBA /* Next sector */
|
||||||
|
adcl $0,GPT_ADDR+GPT_PART_LBA+4
|
||||||
|
jmp load_part
|
||||||
|
|
||||||
|
/*
|
||||||
|
* If loading boot sectors from a GPT partition fails, try booting a MBR part.
|
||||||
|
* Reset stack/segment. Could have been tainted by the GPT loading code.
|
||||||
|
*/
|
||||||
|
try_mbr:
|
||||||
|
xorw %ax,%ax /* Zero */
|
||||||
|
movw %ax,%es /* extra segment */
|
||||||
|
movw $LOAD,%sp /* Reset stack */
|
||||||
|
|
||||||
|
xorw %si,%si /* Will point to active partition */
|
||||||
|
movw $(EXEC+PT_OFF),%bx /* Point to partition table start */
|
||||||
|
movw $0x4,%cx /* Tested entries counter (4 total) */
|
||||||
|
read_mbr_entry:
|
||||||
|
cmpb %ch,(%bx) /* Null entry? (%ch just zeroed) */
|
||||||
|
je next_mbr_entry /* Yes */
|
||||||
|
jg err_part_table /* If 0x1..0x7f */
|
||||||
|
testw %si,%si /* Active already found? */
|
||||||
|
jnz err_part_table /* Yes */
|
||||||
|
movw %bx,%si /* Point to active */
|
||||||
|
next_mbr_entry:
|
||||||
|
addb $0x10,%bl /* Till */
|
||||||
|
loop read_mbr_entry /* done */
|
||||||
|
testw %si,%si /* Active found? */
|
||||||
|
jnz read_bootsect /* Yes, read OS loader */
|
||||||
|
try_diskless:
|
||||||
|
int $0x18 /* Else, BIOS: Diskless boot */
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Ok, now that we have a valid drive and partition entry, load either CHS
|
||||||
|
* or LBA from the partition entry and read the boot sector from the partition.
|
||||||
|
*/
|
||||||
|
read_bootsect:
|
||||||
|
movw %sp,%bx /* Write addr. (%sp points to LOAD) */
|
||||||
|
pushw %si /* Points at active part. entry; */
|
||||||
|
/* save, else 'read' will trash it */
|
||||||
|
test_flag:
|
||||||
|
cmpb $1,%dh /* Test flag set by set_chs above */
|
||||||
|
jz read_chs /* CHS read if set */
|
||||||
|
read_lba:
|
||||||
|
addw $0x8,%si /* Start LBA of partition, 32-bit */
|
||||||
|
movw $LBABUF,%di /* So far either QWORD 1 or 0, so */
|
||||||
|
movsl /* more significant bytes are all 0 */
|
||||||
|
xchg %di,%si /* Copy to buffer and swap pointers */
|
||||||
|
subw $0x4,%si /* Adjust back to start of buffer */
|
||||||
|
call read
|
||||||
|
jmp finished_read /* Skip the CHS setup */
|
||||||
|
read_chs:
|
||||||
|
movb 0x1(%si),%dh /* Load head */
|
||||||
|
movw 0x2(%si),%cx /* Load cylinder:sector */
|
||||||
|
movb $2,%al /* Read two sectors */
|
||||||
|
movb $2,%ah /* BIOS: Read sectors from disk */
|
||||||
|
int $0x13 /* Call the BIOS */
|
||||||
|
finished_read:
|
||||||
|
jc err_reading /* If error */
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Now that we've loaded the bootstrap, check for the 0xaa55 signature. If it
|
||||||
|
* is present, execute the bootstrap we just loaded.
|
||||||
|
*/
|
||||||
|
popw %si /* Restore %si (active part entry) */
|
||||||
|
movb %dl,(%si) /* Patch part record with drive num */
|
||||||
|
cmpw $MAGIC,0x1fe(%bx) /* Bootable? */
|
||||||
|
jne err_noboot /* No, error out. */
|
||||||
|
/* Else, start loader */
|
||||||
|
start_loader:
|
||||||
|
xorw %ax,%ax
|
||||||
|
movw %ax,%es /* Reset %es to zero */
|
||||||
|
jmp $0,$LOAD /* Jump to boot code */
|
||||||
|
|
||||||
|
|
||||||
|
/* Auxiliary functions */
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Load a sector (64-bit LBA at %si) from disk %dl into %es:%bx by creating
|
||||||
|
* a EDD packet on the stack and passing it to the BIOS. Trashes %ax and %si.
|
||||||
|
*/
|
||||||
|
read:
|
||||||
|
pushl 0x4(%si) /* Set the LBA */
|
||||||
|
pushl 0x0(%si) /* address */
|
||||||
|
pushw %es /* Set the address of */
|
||||||
|
pushw %bx /* the transfer buffer */
|
||||||
|
pushw $0x1 /* Read 1 sector */
|
||||||
|
pushw $0x10 /* Packet length */
|
||||||
|
movw %sp,%si /* Packet pointer */
|
||||||
|
movw $0x4200,%ax /* BIOS: LBA Read from disk */
|
||||||
|
int $0x13 /* Call the BIOS */
|
||||||
|
add $0x10,%sp /* Restore stack */
|
||||||
|
jc err_reading /* If error */
|
||||||
|
ret
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Output an ASCIZ string pointed at by %si to the console via the BIOS.
|
||||||
|
*/
|
||||||
|
putstr.0:
|
||||||
|
movw $0x7,%bx /* Page:attribute */
|
||||||
|
movb $0xe,%ah /* BIOS: Display */
|
||||||
|
int $0x10 /* character */
|
||||||
|
putstr:
|
||||||
|
lodsb /* Get character */
|
||||||
|
testb %al,%al /* End of string? */
|
||||||
|
jnz putstr.0 /* No */
|
||||||
|
ret
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Various error message entry points.
|
||||||
|
*/
|
||||||
|
err_part_table:
|
||||||
|
movw $msg_badtable,%si /* "Bad Part. Table!" */
|
||||||
|
call putstr
|
||||||
|
jmp halt
|
||||||
|
|
||||||
|
|
||||||
|
err_reading:
|
||||||
|
movw $msg_ioerror,%si /* "Read Error!" */
|
||||||
|
call putstr
|
||||||
|
jmp halt
|
||||||
|
|
||||||
|
|
||||||
|
err_noboot:
|
||||||
|
movw $msg_noloader,%si /* "No Sys Loader!" */
|
||||||
|
call putstr
|
||||||
|
/* fall-through to halt */
|
||||||
|
|
||||||
|
|
||||||
|
halt:
|
||||||
|
cli
|
||||||
|
hlt
|
||||||
|
jmp halt
|
||||||
|
|
||||||
|
|
||||||
|
/* Data section */
|
||||||
|
|
||||||
|
|
||||||
|
#ifdef VALIDATE_DRV
|
||||||
|
/* Messages must be shortened so the code fits 440 bytes */
|
||||||
|
msg_badtable: .asciz "BadPTbl!"
|
||||||
|
msg_ioerror: .asciz "IOErr!"
|
||||||
|
msg_noloader: .asciz "NoSysLdr!"
|
||||||
|
#else
|
||||||
|
msg_badtable: .asciz "Bad Part. Table!"
|
||||||
|
msg_ioerror: .asciz "Read Error!"
|
||||||
|
msg_noloader: .asciz "No Sys Loader!"
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/* Boot partition UUID signature */
|
||||||
|
.org UUID,0x0 /* Zero-pad up to UUID offset */
|
||||||
|
|
||||||
|
boot_uuid:
|
||||||
|
.long 0x42465331 /* 'BFS1' (formally, UUID time-low) */
|
||||||
|
.word 0x3ba3 /* UUID time-mid */
|
||||||
|
.word 0x10f1 /* UUID time-high & version (v1) */
|
||||||
|
.byte 0x80 /* UUID DCE 1.1 variant */
|
||||||
|
.byte 0x2a /* '*' (formally, UUID clock-seq-low) */
|
||||||
|
.byte 0x48 /* 'H' */
|
||||||
|
.byte 0x61 /* 'a' */
|
||||||
|
.byte 0x69 /* 'i' */
|
||||||
|
.byte 0x6b /* 'k' */
|
||||||
|
.byte 0x75 /* 'u' */
|
||||||
|
.byte 0x21 /* '!' */
|
||||||
|
|
||||||
|
#ifndef MBR_CODE_ONLY
|
||||||
|
/* Disk signature */
|
||||||
|
.org DISKSIG,0x0 /* Zero-pad up to signature offset */
|
||||||
|
|
||||||
|
sig:
|
||||||
|
.long 0 /* OS Disk Signature */
|
||||||
|
.word 0 /* "Unknown" in PMBR */
|
||||||
|
|
||||||
|
/* Partition table */
|
||||||
|
.org PT_OFF,0x0 /* Won't pad, just documenting */
|
||||||
|
|
||||||
|
partbl:
|
||||||
|
.fill 0x10,0x4,0x0 /* Partition table */
|
||||||
|
.word MAGIC /* Magic number */
|
||||||
|
#endif
|
||||||
@@ -1,395 +0,0 @@
|
|||||||
; Copyright 2011, Jean-Loïc Charroud, [email protected]
|
|
||||||
; Distributed under the terms of the MIT License or LGPL v3
|
|
||||||
;
|
|
||||||
; Haiku (C) Copyright Haiku 2011
|
|
||||||
; MBR Boot code
|
|
||||||
;
|
|
||||||
; assemble the Master boot record with:
|
|
||||||
; nasm -f bin -O5 -o mbr.bin mbr.S
|
|
||||||
;
|
|
||||||
; assemble the MBR's code (does not contain the partiton table
|
|
||||||
; nor the MAGIC code) with:
|
|
||||||
; nasm -f bin -O5 -o mbrcode.bin mbr.S -dMBR_CODE_ONLY=1
|
|
||||||
|
|
||||||
|
|
||||||
;%define DEBUG 1
|
|
||||||
;%define MBR_CODE_ONLY 1
|
|
||||||
|
|
||||||
|
|
||||||
;CONST
|
|
||||||
%assign DISKSIG 440 ; Disk signature offset
|
|
||||||
%assign PT_OFF 0x1be ; Partition table offset
|
|
||||||
%assign MAGIC_OFF 0x1fe ; Magic offset
|
|
||||||
%assign MAGIC 0xaa55 ; Magic bootable signature
|
|
||||||
%assign SECSIZE 0x200 ; Size of a single disk sector
|
|
||||||
%assign FLG_ACTIVE 0x80 ; active partition flag
|
|
||||||
%assign SECTOR_COUNT 0x01 ; Number of record to load from
|
|
||||||
; the ctive partition
|
|
||||||
|
|
||||||
%assign LOAD 0x7c00 ; Load address
|
|
||||||
%assign EXEC 0x600 ; Execution address
|
|
||||||
%assign HEAP EXEC+SECSIZE ; Execution address
|
|
||||||
|
|
||||||
;BIOS calls
|
|
||||||
%assign BIOS_VIDEO_SERVICES 0x10; ah - function
|
|
||||||
%assign BIOS_DISK_SERVICES 0x13
|
|
||||||
%assign BIOS_KEYBOARD_SERVICES 0X16
|
|
||||||
%assign BIOS_BASIC 0X18
|
|
||||||
%assign BIOS_REBOOT 0X19
|
|
||||||
|
|
||||||
;BIOS calls parameters
|
|
||||||
; video services
|
|
||||||
%assign WRITE_CHAR 0x0e; al - char
|
|
||||||
; bh - page?
|
|
||||||
|
|
||||||
; disk services
|
|
||||||
%assign READ_DISK_SECTORS 0x02; dl - drive
|
|
||||||
; es:bx - buffer
|
|
||||||
; dh - head
|
|
||||||
; ch7:0 - track7:0
|
|
||||||
; cl7:6 - track9:8
|
|
||||||
; 5:0 - sector
|
|
||||||
; al - sector count
|
|
||||||
; -> al - sectors read
|
|
||||||
%assign READ_DRV_PARAMETERS 0x08; dl - drive
|
|
||||||
; -> cl - max cylinder 9:8
|
|
||||||
; - sectors per track
|
|
||||||
; ch - max cylinder 7:0
|
|
||||||
; dh - max head
|
|
||||||
; dl - number of drives (?)
|
|
||||||
%assign CHK_DISK_EXTENTIONS 0x41; bx - 0x55aa
|
|
||||||
; dl - drive
|
|
||||||
; -> success: carry clear
|
|
||||||
; ah - extension version
|
|
||||||
; bx - 0xaa55
|
|
||||||
; cx - support bit mask
|
|
||||||
; 1 - Device Access using the
|
|
||||||
; packet structure
|
|
||||||
; 2 - Drive Locking and
|
|
||||||
; Ejecting
|
|
||||||
; 4 - Enhanced Disk Drive
|
|
||||||
; Support (EDD)
|
|
||||||
; -> error: carry set
|
|
||||||
%assign EXTENDED_READ 0x42; dl - drive
|
|
||||||
; ds:si - address packet
|
|
||||||
; -> success: carry clear
|
|
||||||
; -> error: carry set
|
|
||||||
|
|
||||||
%assign FIXED_DSK_SUPPORT 0x1 ; flag indicating fixed disk
|
|
||||||
; extension command subset
|
|
||||||
|
|
||||||
; keyboard services
|
|
||||||
%assign READ_CHAR 0x00; -> al - ASCII char
|
|
||||||
|
|
||||||
;MACRO
|
|
||||||
; nicer way to get the size of a structure
|
|
||||||
%define sizeof(s) s %+ _size
|
|
||||||
|
|
||||||
; using a structure in a another structure definition
|
|
||||||
%macro nstruc 1-2 1
|
|
||||||
resb sizeof(%1) * %2
|
|
||||||
%endmacro
|
|
||||||
|
|
||||||
; nicer way to access GlobalVariables
|
|
||||||
%macro declare_var 1
|
|
||||||
%define %1 HEAP + GlobalVariables. %+ %1
|
|
||||||
%endmacro
|
|
||||||
|
|
||||||
%macro puts 1
|
|
||||||
mov si, %1
|
|
||||||
call _puts
|
|
||||||
%endmacro
|
|
||||||
|
|
||||||
%macro error 1
|
|
||||||
mov si, %1
|
|
||||||
jmp _error
|
|
||||||
%endmacro
|
|
||||||
|
|
||||||
;TYPEDEFS
|
|
||||||
; 64 bit value
|
|
||||||
struc quadword
|
|
||||||
.lower resd 1
|
|
||||||
.upper resd 1
|
|
||||||
endstruc
|
|
||||||
|
|
||||||
struc CHS_addr
|
|
||||||
.head resb 1
|
|
||||||
.sector resb 1
|
|
||||||
.cylindre resb 1
|
|
||||||
endstruc
|
|
||||||
|
|
||||||
struc PartitionEntry
|
|
||||||
.status resb 1
|
|
||||||
.CHS_first nstruc CHS_addr
|
|
||||||
.type resb 1
|
|
||||||
.CHS_last nstruc CHS_addr
|
|
||||||
.LBA_start resd 1
|
|
||||||
.LBA_size resd 1
|
|
||||||
endstruc
|
|
||||||
|
|
||||||
; address packet as required by the EXTENDED_READ BIOS call
|
|
||||||
struc AddressPacket
|
|
||||||
.packet_size resb 1
|
|
||||||
.reserved resb 1
|
|
||||||
.block_count resw 1
|
|
||||||
.buffer resd 1
|
|
||||||
.sector nstruc quadword
|
|
||||||
;.long_buffer nstruc quadword
|
|
||||||
; We don't need the 64 bit buffer pointer. The 32 bit .buffer is more
|
|
||||||
; than sufficient.
|
|
||||||
endstruc
|
|
||||||
|
|
||||||
; Structure containing the variables that don't need pre-initialization.
|
|
||||||
; this structure will be allocated onto our "heap".
|
|
||||||
struc GlobalVariables
|
|
||||||
.boot_drive_id resd 1
|
|
||||||
.boot_partition resd 1
|
|
||||||
.address_packet nstruc AddressPacket
|
|
||||||
endstruc
|
|
||||||
|
|
||||||
;alias for easy access to our global variables
|
|
||||||
declare_var boot_drive_id
|
|
||||||
declare_var boot_partition
|
|
||||||
declare_var address_packet
|
|
||||||
|
|
||||||
;/////////////////////////////////////////////////////////////////////////
|
|
||||||
;// A 512 byte MBR boot manager that simply boots the active partition. //
|
|
||||||
;/////////////////////////////////////////////////////////////////////////
|
|
||||||
; 16 bit code
|
|
||||||
SECTION .text
|
|
||||||
BITS 16
|
|
||||||
ORG EXEC ; MBR is loaded at 0x7c00 but relocated at 0x600
|
|
||||||
start: ; we run the LOADed code
|
|
||||||
cli ; disable interrupts
|
|
||||||
cld ; clear direction flag (for string operations)
|
|
||||||
init:
|
|
||||||
xor ax, ax ; Zero
|
|
||||||
mov es, ax ; Set up extra segment
|
|
||||||
mov ds, ax ; Set up data segment
|
|
||||||
mov ss, ax ; Set up stack segment
|
|
||||||
mov sp, LOAD ; Set up stack pointer
|
|
||||||
|
|
||||||
;init our heap allocated variables with zeros
|
|
||||||
mov di, HEAP ;start adress
|
|
||||||
mov cx, sizeof(GlobalVariables) ;size
|
|
||||||
rep ; while(cx--)
|
|
||||||
stosb ; es[di++]:=al;
|
|
||||||
|
|
||||||
; Relocate ourself to a lower address so that we are out of the way
|
|
||||||
; when we load in the bootstrap from the partition to boot.
|
|
||||||
reloc:
|
|
||||||
mov si, LOAD ; Source
|
|
||||||
; init AddressPacket.buffer now since LOAD is in 'si'
|
|
||||||
mov [address_packet+AddressPacket.buffer],si
|
|
||||||
mov byte[address_packet+AddressPacket.packet_size],sizeof(AddressPacket)
|
|
||||||
mov byte[address_packet+AddressPacket.block_count],SECTOR_COUNT
|
|
||||||
|
|
||||||
mov di, EXEC ; Destination
|
|
||||||
mov ch, 1 ; count cx:=256 (cl cleared by precedent rep call)
|
|
||||||
rep ; while(cx--)
|
|
||||||
movsw ; es[di++]:=ds[si++]
|
|
||||||
; //di and si are incremented by sizeof(word)
|
|
||||||
jmp word 0x0000:continue; FAR jump to the relocated "continue" (some
|
|
||||||
; BIOSes initialise CS to 0x07c0 so we must set
|
|
||||||
; CS correctly)
|
|
||||||
|
|
||||||
continue: ; Now we run EXEC_based relocated code
|
|
||||||
sti ; enable interrupts
|
|
||||||
%ifdef DEBUG
|
|
||||||
puts kMsgStart
|
|
||||||
%endif
|
|
||||||
|
|
||||||
search_active_partition:
|
|
||||||
mov si,EXEC+PT_OFF ; point to first table entry
|
|
||||||
mov al,04 ; there are 4 table entries
|
|
||||||
.loop: ; SEARCH FOR AN ACTIVE ENTRY
|
|
||||||
cmp byte[si],FLG_ACTIVE ; is this the active entry?
|
|
||||||
je found_active ; yes
|
|
||||||
add si, sizeof(PartitionEntry) ; next PartitionEntry
|
|
||||||
dec al ; decrease remaining entry count
|
|
||||||
jnz .loop ; loop if entry count > 0
|
|
||||||
jmp no_bootable_active_partition; last partition reached
|
|
||||||
|
|
||||||
found_active: ; active partition (pointed by si)
|
|
||||||
mov [boot_partition],si ; Save active partition pointer
|
|
||||||
|
|
||||||
.get_read_sector: ; initialise address_packet:
|
|
||||||
mov eax,[si + PartitionEntry.LBA_start]
|
|
||||||
mov [address_packet+AddressPacket.sector],eax
|
|
||||||
|
|
||||||
; if LBA_adress equals 0 then it's not a valid PBR (it is the MBR)
|
|
||||||
; this can happen when we only have a CHS adress in the partition entry
|
|
||||||
test eax, eax ;if ( LBA_adress == 0 )
|
|
||||||
jz no_disk_extentions ;then no_disk_extentions()
|
|
||||||
|
|
||||||
check_disk_extensions:
|
|
||||||
; Note: this test may be unnecessary since EXTENDED_READ also
|
|
||||||
; set the carry flag when extended calls are not supported
|
|
||||||
%ifdef DEBUG
|
|
||||||
puts kMsgCheckEx
|
|
||||||
%endif
|
|
||||||
|
|
||||||
mov ah, CHK_DISK_EXTENTIONS ; set command
|
|
||||||
mov bx, 0x55aa ; set parameter : hton(MAGIC)
|
|
||||||
; dl has not changed yet, still contains the drive ID
|
|
||||||
int BIOS_DISK_SERVICES ; if( do_command() <> OK )
|
|
||||||
jc no_disk_extentions ; then use simple read operation
|
|
||||||
; else use extended read
|
|
||||||
disk_extentions:
|
|
||||||
%ifdef DEBUG
|
|
||||||
puts kMsgRead_Ex
|
|
||||||
%endif
|
|
||||||
|
|
||||||
; load first bloc active partition
|
|
||||||
; dl has not changed yet, still contains the drive ID
|
|
||||||
mov si, address_packet ; set command parameters
|
|
||||||
mov ah, EXTENDED_READ ; set command
|
|
||||||
.read_PBR:
|
|
||||||
int BIOS_DISK_SERVICES ; if ( do_command() <> OK )
|
|
||||||
jc no_disk_extentions ; then try CHS_read();
|
|
||||||
|
|
||||||
check_for_bootable_partition:
|
|
||||||
cmp word[LOAD+MAGIC_OFF],MAGIC ; if ( ! volume.isBootable() )
|
|
||||||
jne no_bootable_active_partition; then error();
|
|
||||||
|
|
||||||
jump_PBR:
|
|
||||||
%ifdef DEBUG
|
|
||||||
puts kMsgBootPBR
|
|
||||||
call _pause
|
|
||||||
%else
|
|
||||||
puts kMsgStart
|
|
||||||
%endif
|
|
||||||
|
|
||||||
; jump to 0x7c00 with :
|
|
||||||
; - CS=0
|
|
||||||
; - DL=drive number
|
|
||||||
; - DS:SI=pointer to the selected partition table
|
|
||||||
; entry (required by some PBR)
|
|
||||||
|
|
||||||
; dl has not changed yet, still contains the drive ID
|
|
||||||
mov si, [boot_partition]
|
|
||||||
jmp LOAD ; jump into partition boot loader
|
|
||||||
|
|
||||||
no_disk_extentions:
|
|
||||||
%ifdef DEBUG
|
|
||||||
puts kMsgNoExtentions
|
|
||||||
%endif
|
|
||||||
|
|
||||||
mov si, [boot_partition] ; Restore active partition pointer
|
|
||||||
|
|
||||||
;load CHS PBR sector info
|
|
||||||
mov dh, [si+1] ; dh 7:0 = head 7:0 (0 - 255)
|
|
||||||
mov cx, [si+2] ; cl 5:0 = sector 7:0 (1 - 63)
|
|
||||||
; cl 7:6 = cylinder 9:8 (0 - 1023)
|
|
||||||
; ch 7:0 = cylinder 7:0
|
|
||||||
.check_Sector:
|
|
||||||
mov al, cl
|
|
||||||
and al, 0x3F ; extract sector
|
|
||||||
test al, al; ; if (sector==0)
|
|
||||||
jz no_bootable_active_partition; then error("invalid sector");
|
|
||||||
cmp al, 0x3F ; if( (Sector == 63)
|
|
||||||
jne .CHS_valid ;
|
|
||||||
.check_Cylinder:
|
|
||||||
mov ax, cx
|
|
||||||
shr ah, 6
|
|
||||||
cmp ax, 0x03FF ; and (Cylinder == 1023)
|
|
||||||
jne .CHS_valid
|
|
||||||
.check_Head:
|
|
||||||
cmp dh, 0xFF ; and ( (Head == 255)
|
|
||||||
jne .CHS_valid
|
|
||||||
cmp dh, 0xFE ; or (Head == 254) ) )
|
|
||||||
je no_bootable_active_partition; then error("invalid CHS_adress");
|
|
||||||
|
|
||||||
.CHS_valid:
|
|
||||||
; dl has not changed yet, still contains the drive ID
|
|
||||||
mov bx, LOAD ; set buffer
|
|
||||||
mov al, SECTOR_COUNT ; set Size
|
|
||||||
mov ah, READ_DISK_SECTORS ; set read command
|
|
||||||
int BIOS_DISK_SERVICES ; if ( do_command() == OK )
|
|
||||||
jnc check_for_bootable_partition; then resume(normal boot sequence)
|
|
||||||
; else continue;
|
|
||||||
|
|
||||||
no_bootable_active_partition:
|
|
||||||
mov si, kMsgNoBootable
|
|
||||||
;jmp _error ; _error is the next line !
|
|
||||||
|
|
||||||
_error:
|
|
||||||
; display a non-empty null-terminated string on the screen,
|
|
||||||
; wait for a key pressed and go back to the bios
|
|
||||||
; IN :
|
|
||||||
; - si = address of string to display
|
|
||||||
; OUT :
|
|
||||||
; DIRTY :
|
|
||||||
; - ax
|
|
||||||
; - si
|
|
||||||
call _puts
|
|
||||||
call _pause
|
|
||||||
puts kMsgROMBASIC
|
|
||||||
int BIOS_BASIC ; BIOS_BASIC give the control back
|
|
||||||
; to the BIOS. Doing so, let some
|
|
||||||
; BIOSes try to boot an alternate
|
|
||||||
; device (PXE/CD/HDD : see your
|
|
||||||
; BIOS' boot device order )
|
|
||||||
_pause:
|
|
||||||
; wait for a key pressed
|
|
||||||
; IN :
|
|
||||||
; OUT :
|
|
||||||
; DIRTY :
|
|
||||||
; - ax
|
|
||||||
mov ah, READ_CHAR
|
|
||||||
int BIOS_KEYBOARD_SERVICES
|
|
||||||
ret
|
|
||||||
|
|
||||||
_puts:
|
|
||||||
; display a non-empty null-terminated string on the screen
|
|
||||||
; IN :
|
|
||||||
; - si = address of string to display
|
|
||||||
; OUT :
|
|
||||||
; DIRTY :
|
|
||||||
; - ax
|
|
||||||
; - bx
|
|
||||||
; - si
|
|
||||||
xor bx, bx ; bx:=0
|
|
||||||
.loop: ; do {
|
|
||||||
lodsb ; al=[si++];
|
|
||||||
mov ah, WRITE_CHAR ;
|
|
||||||
int BIOS_VIDEO_SERVICES ; WRITE_CHAR(al)
|
|
||||||
or al, al ; } while (al<>0);
|
|
||||||
jnz .loop
|
|
||||||
ret
|
|
||||||
|
|
||||||
data:
|
|
||||||
kMsgROMBASIC db 'ROM BASIC',0
|
|
||||||
kMsgNoBootable db 'No bootable active volume',13,10,0
|
|
||||||
kMsgStart db 'Loading system',10,13,0
|
|
||||||
|
|
||||||
%ifdef DEBUG
|
|
||||||
kMsgBootPBR db 'JMP PBR',13,10,0
|
|
||||||
kMsgRead_Ex db 'Read_ex block',13,10,0
|
|
||||||
kMsgCheckEx db 'CheckEx',13,10,0
|
|
||||||
kMsgNoExtentions db 'Read block',13,10,0
|
|
||||||
kMsgReloc db 'reloc MBR',13,10,0
|
|
||||||
%endif
|
|
||||||
|
|
||||||
; check whether the code is small enough to fit in the boot code area
|
|
||||||
end:
|
|
||||||
%if end - start > DISKSIG
|
|
||||||
%error "Code exceeds master boot code area!"
|
|
||||||
%endif
|
|
||||||
|
|
||||||
%ifdef MBR_CODE_ONLY
|
|
||||||
;just build the code.
|
|
||||||
;Do not generate the datas
|
|
||||||
%else
|
|
||||||
%rep start + DISKSIG - end
|
|
||||||
db 0 ;fill the rest of the code area
|
|
||||||
%endrep
|
|
||||||
kMbrDiskID dd 0 ;Disk signature
|
|
||||||
dw 0 ;reserved
|
|
||||||
PartitionTable times PartitionEntry_size * 4 db 0
|
|
||||||
DiskSignature:
|
|
||||||
%if DiskSignature - start <> MAGIC_OFF
|
|
||||||
%error "incorrect Disk Signature offset"
|
|
||||||
%endif
|
|
||||||
kMbrSignature db 0x55, 0xAA
|
|
||||||
%endif
|
|
||||||
Reference in New Issue
Block a user