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diff --git a/util/ADLO/README b/util/ADLO/README deleted file mode 100644 index d1ad9754a2..0000000000 --- a/util/ADLO/README +++ /dev/null @@ -1,231 +0,0 @@ -========================================== -$Id: README,v 1.1 2002/11/25 02:07:53 rminnich Exp $ -========================================== - -ADLO - - A project to combine coreboot and BOCHS BIOS to add support - for booting legacy applications, such as Microsoft Windows. - -========================================== - -Boot Overvew: - - ADLO requires an boot loader with ELF support. - In our case it is either coreboot or EtherBOOT. - - Sample execution paths: - -coreboot -> ADLO -> LILO -> LINUX - -coreboot -> EtherBOOT -> ADLO -> LILO -> LINUX - - Then it can start any real mode application. - In our case it could be LILO or GRUB, but - choices are not limited to this. - -========================================== - -ADLO overview: - - -Elf header - -mainteance routines - -bochs bios - -vga bios - ------------------------------------------- - -Elf header - - hand crafted binary. Currently there are 3 diff binaries - for three different sizes of payload (65kb,113kb,129kb). - - they are catted at beginning of file - ------------------------------------------- - -mainteance routines - - this is the loader.s file which gets compiled into loader.o binary - - it is catted 2nd right after elf header and it is where - control is being transfered when the elf is executed. - - it consist of : - -tuneups: - select device to boot - set memory for Int15/EAX=E820 - enable LBA - copy coreboot table [TODO] - -shadow : - enable/write/read - -copy: - bochs @ 0xF00000 - video bios (binary only) @ 0xC00000 - -switch - from Real to Protected Mode - -jump - jmp to the bios at 0xFFFF:0x0000 - - we must have bios payload always at 1kb - offset from start of ELF payload so loader.o - must be always 1024 bytes. - ------------------------------------------- - -BOCHS BIOS - - we have taken the boch's project and just extracted - its bios from it only. it took us (so far) only - minor modifications in order to make it work. - - basically it is the following directory in the - bochs sources - - bochs-cvs/bochs/bios - - of all files there the rombios.c is the key file. - Most of the times our patches are against current - version of the rombios.c file. We try to feed back - the patches to bochs maintainers so that's possible - to use the bochs bios as is. - - the boch's related stuff are in bochs subdirectory. - - building boch's bios is as simple as - - cd bochs/bochs-cvs/bochs/bios - make - - the resulting file rombios.bin is our bios image. - - ----- - At present time, it is recommended to use - dev86-0.16.3 + my patch in order to compile - bochs' bios. The dev86 package can be found - at: - - http://www.cix.co.uk/~mayday/ - - prepatched sources at: - - http://www.missl.cs.umd.edu/~adam/dev86-0.16.3-MSR.tgz - ------------------------------------------- - -Video BIOS - - Video BIOS we use is binary only, so far. - - At the present time we are using the original - Video BIOS as supplied from the system. - - To get the image simply type: - - make makevideobios - - The right thing will happen. For refernece the - magic line in the Makefile is: - - videobios: - dd if=/proc/kcore \ - of=./video.bios.bin \ - bs=1 count=65536 skip=790528 - - --------------- - - We assume it is located at 0xC00000-0xE00000 - and we use 'dd and /proc/kcore to extract it - (obviously it works as root only). - - Obviously it needs to be done with original - (as shipped by manufactuer bios) so it should - be done as the first step of the ADLO setup. - - --------------- - - The /proc/kcore is in ELF format (linux kernel - 2.4.x and later) so if we want to get accurate - image of ram we must skip the ELF header. - The magic command is : - - readelf -a /proc/kcore - -Program Headers: - Type Offset VirtAddr PhysAddr FileSiz MemSiz - NOTE 0x0007d4 0x00000000 0x00000000 0x005b0 0x00000 - LOAD 0x001000 0xc0000000 0x00000000 0xff60000 0xff60000 - ^^^^^^^^ - - There we look for the first LOAD section, and see what - is its offset (for us it is 0x1000) - - --------------- - - 64KiB = 65536 - - 0x0C 00 00 + 0x10 00 = 790528 - - --------------- - - On technical note in our case video bios - is just 48kb, but for paranoia sake we copy - 64kb. - -========================================== - -Environment overview - -ADLO is an ELF file and thus can be loaded either directly from 1) -coreboot, or 2) via EtherBOOT, or 3) via EtherBOOT+ AA patch for FS -support. - -1) -Both coreboot and ADLO are on the same EEPROM chip. From end-user -viewpoint it is probably the most similar to the bios classic. -(computer boots up and just loads whatever is in MBR). - -2) -Set it up in /tftpboot directory on dhcp/tftp server and have it served -from there. (this is how we did the development) - -3) -Use AA patch and put it as /kernel file and it will be then loaded by -etherboot from local hard disk. - - ------------------------------------------- - -Before ADLO starts. - - ADLO requires an boot loader with ELF support. - In our case it is: - - -coreboot - -coreboot and EtherBOOT - -coreboot and EtherBOOT + AA polled I/O patch (w/ FS support). - - As little as coreboot only is required to get ADLO - up and running. - - For development purposes it is recommended full set of - coreboot + EtherBOOT and boot via DHCP/TFTP. - ------------------------------------------- - -After ADLO finish. - - ADLO will attempt to locate the first hard disk - and read MBR from it and execute. - - Then it can start any real mode application. - In our case it could be LILO or GRUB - but choices are not limited to this. - - In our case it would cause LILO to load - (fully usable) and from there it was able to - execute simple programs. so far the list - of the program is limited to linux which - runs somewhat. More to come in future. - -========================================== |