GRUB on DoC Millennium/2000 - Instructions
mark at lakeshoremicro.com
Tue Jun 18 12:55:17 EDT 2002
My apologies for screwing up the attachment. Here it is in text:
Booting GRUB on the DiskOnChip Millennium
The following procedure was done on a desktop PC, using an 8MB DoC Millennium
and the M-Sys ISA Evaluation card. A DOS partition was used to run the M-Sys
utilities, prior to installing GRUB. This procedure *might* work with a DoC
2000 -- but it has not been verified.
The Linux kernel must have the following MTD options either built-in or
compiled as modules:
MTD Support: MTD, Debugging, Direct char device access, NFTL, NTFL
Self-contained MTD Device Drivers: M-Systems DiskOnChip 2000 and
In the following examples, a 2.4.18 kernel called "vmlinuz-doc" with the
above MTD options built-in was used.
2. Save DoC contents, and the Bad Block Table
Get the latest version of the DOS based M-Systems DiskOnChip Software
Utilities from www.m-sys.com. If desired, the GETIMAGE utility can be used
to save the current contents of the DoC:
getimage /win:xxxx <filename>
(where xxxx is the DoC base memory address in hex (window), for example:
**IMPORTANT**: Save the Bad Block Table! Before attempting to boot with
GRUB, make sure that the bad block table has been saved. Doing this insures
you can always restore the BBT in the event of the DoC being corrupted or
dformat /win:xxxx /noformat /log:<filename.txt>
This creates a text file containing a list of all the bad blocks on the DoC.
The dformat "uselog" option may be used to restore the BBT if needed.
will also display some detailed information about the DoC and the bad block
3. Verify TrueFFS Driver Version
The newer versions (5.0 or later) of the M-Systems DOC firmware may not work
correctly with the latest version of the MTD drivers. This has something to
do with the "UnitSizeFactor != 1" problem documented elsewhere. An earlier
version (4.2) seems to work fine.
Using version 4.2 of the DOS TrueFFS utilities available from M-Systems
(www.m-sys.com), verify that the DOC is recognized, and that the firmware
version is 4.2:
If the firmware version is 5.0 or later, run the DFORMAT utility:
dformat /win:xxxx /s:doc42.exb
4. Patch and compile GRUB
Get the latest grub sources:
tar xzvf grub-0.92.tar.gz
Get the latest MTD sources:
cvs -d :pserver:anoncvs at cvs.infradead.org:/home/cvs login
(password = anoncvs)
cvs -z3 -d :pserver:anoncvs at cvs.infradead.org:/home/cvs co mtd
Patch GRUB with DiskOnChip updates:
patch -p0 -i ../mtd/patches/grub-2002-02-19-doc.patch
This patch may fail on the "ChangeLog" file, but all other files should patch
correctly. The 2002-02-19-doc patch was originally a patch against grub
5. Build GRUB:
aclocal && automake && autoconf
If there are any error messages here, you'll probably need up update automake
and autoconf to the latest versions.
./configure --enable-diskonchip-mil512 --enable-ext2fs
--disable-ffs --disable-xfs --disable-jfs --disable-vstafs
--disable-reiserfs --disable-minix --disable-fat
See "README_DiskOnChip" for more information regarding the ./configure
options, specifically the difference between "-mil256" and "-mil512".
6. Copy GRUB to DOC
./doc_loadbios /dev/mtd0 ../../grub-0.92/stage1/grub_firmware
If an error is reported regarding /dev/mtd0, you might need to run the
./MAKEDEV script to create the proper device MTD device entries in the /dev
7. TURN OFF PC!
**IMPORTANT** - The PC should be turned off (not just rebooted) after running
doc_loadbios. This may not be necessary on all types of hardware, but it was
required on my PC. From M-Systems application note DOC-044:
The boot block is implemented as a XIP block located between the flash media
and the system bus. After the DiskOnChip Millennium powers-on, or when its
reset signal is negated, the contents of the first page of flash memory are
copied into the Boot Block.
The "doc_loadbios" utility copies data to this first page of flash memory.
My PC must not be "negating the reset signal" to the DoC on a normal reboot
-- a full power cycle is required to copy the flash memory to the boot block.
8. Change Boot Sequence
In the BIOS setup, select NETWORK (or NIC, or its equivalent) as the first
Selecting "--enable-diskonchip-biosnetboot" causes the GRUB/DoC code to hook
INT 18H, which is historically known as the "BASIC interrupt" or "Diskless
Boot Interrupt". Using this option with the DoC on a PC is useful because
you change easily change the boot sequence back to the hard drive when needed.
If the BIOS does not have a NETWORK boot option, it may be possible to
disable the "biosnetboot" option, rebuild GRUB, and copy grub_firmware to the
DoC again. In this case, the GRUB/DoC code will hook the INT 19H (bootstrap)
handler. This doesn't work at all on my PC, but theoretically it should
override any boot sequence options in the BIOS setup.
The downside of this option (in a PC environment, anyway) is that you may
need to physically remove the DoC (or eval-board) to get the PC to boot from
the hard drive again. If that happens, it may be necessary to reinstall the
DoC *after* the PC has booted, into a powered up eval board. Of course, this
is *not* recommended, but it has been done...
9. Verify GRUB boot
The PC should now boot from the DiskOnChip. The BIOS may say something like
"Searching for boot record from Network...". The first DoC messages
displayed should be:
DoC Mil D000
Jumping to Grub
DiskOnChip Millennium found at d0000
Where D000 is the "window" described earlier.
When the boot process completes, there should be a "grub>" command line. We
haven't installed a kernel or a "menu.lst" file on the DiskOnChip yet, so
this step is just to verify that the "grub_firmware" was installed correctly,
and that the DoC will boot.
At this point, you can either reboot again, change the boot sequence back to
IDE (or whatever), and boot back into Linux. Alternatively, if you know
where your kernel and root filesystem is on the hard drive, simply type
kernel (hd0,0)/vmlinuz-doc root=/dev/hda2
10. Partition the DiskOnChip
If /dev/nftla is recognized, there will probably be one FAT12 partition on
the DiskOnChip. In this case, it won't be necessary to run the Linux
"nftl_format" or "eraseall" utilities. Use fdisk to delete this partition,
and continue with step #11.
NOTE: The "eraseall" utility can be dangerous as it will complete erase the
DoC, including the bad block table -- saving the BBT as described in step #2
is highly recommended.
If /dev/ntfla is NOT recognized, use the nftl_format program:
./nftl_format /dev/mtd0 98304
The "start offset" of 98304 insures that the grub_firmware is not
overwritten. As nftl_format runs, there should be notices about "skipping
bad zone (factory marked)". The bad zone values should be identical to the
values in the file created in step #2.
After nftl_format is complete, reboot the PC.
11. Create ext2 partition
To boot directly from the DoC, we'll need to create an ext2 partition, and
install the kernel and GRUB menu.lst file:
n p 1 <enter> <enter> (create new primary partition, using defaults)
w (save new partition info)
mount -t ext2 /dev/nftla1 /mnt/doc
mkdir -p /mnt/doc/boot/grub
cp /boot/vmlinuz-doc /mnt/doc/boot
Now create a "menu.lst" file in /mnt/doc/boot/grub. This file should contain
title DoC Millennium Boot
kernel (dc0,0)/boot/vmlinuz-doc root=/dev/hdaX
Where hdaX is the hard drive that contains your root Linux filesystem. You
could also add another entry to the file to boot directly from the hard
drive, if desired.
Umount the /mnt/doc directory, and reboot the PC.
At this point, the PC should boot entirely from the DoC, and attempt to mount
the root filesystem on your hard drive. If this works, the next step to a
fully self-contained boot is to create a full root filesystem or ramdisk on
the DoC. Once that has been done, change the "root=/dev/hdaX" option to
Thanks to Ilguiz Latypov <ilatypov at superbt.com> for reviewing these
instructions, and for answering many questions related to GRUB on the
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