Booting from a DiskOnChip2000

Booting from a DiskOnChip2000

[Thomas Preisig]

Hi

I use a DiskOnChip 2000 and an Allwell Settopbox. I compiled the 2.4.18
Linuxkernel with the MTD drivers.
Mounting the DOC into the /mnt directory is no problem but now I've
tried to install lilo on the DOC. I used a patched lilo version 21 from
M-System. If I run lilo I get the message: Sorry don't know how to
handle device 0x5d01.

Bye
Tom



Content Security by MailMarshal

Re: Booting from a DiskOnChip2000

[Ilguiz Latypov]

Thomas,

I believe lilo can talk to devices by means of BIOS calls.  If I
understand correctly, the M-Systems patch to lilo adds the mapping of the
/dev/ftla (?) root device name to the appropriate BIOS disk number.

I infer from your description that you haven't made a complete choice
between using the M-System's Linux driver and the MTD doc2000.c driver.

If you are going for M-System's driver, I think you may need to specify
the correct device name (/dev/ftla ?) as a root device (and optionally as
a boot device) in /etc/lilo.conf.

Then the lilo command should be able to write down the block numbers of
the kernel image it needs to load at system startup.

If you are going for the MTD doc2000.c driver which doesn't attempt to
emulate age old real mode BIOS API, then the bootloader will have to
access the content of the NFTL layer by using a bootstrap driver similar
to the kernel doc2000.c module.  

The MTD CVS repository contains the patch to the GRUB bootloader which
performs the above bootstrap access.  As a bonus, the GRUB bootloader
doesn't require any block numbers list to find the kernel image as it has
the bootstrap drivers for the most of filesystems as well.

The latest DOC 2000 / Millennium patch is in CVS directory

        mtd/patches/grub-2002-02-19-doc.patch

You may need to download the source code of GRUB off its own CVS
repository at

        http://savannah.gnu.org/projects/grub/

The copy of the DOC 2000 / Millennium patch can also be found in the Patch
Area of the GRUB project.

Ilguiz

On Wed, 24 Apr 2002, Thomas Preisig wrote:

> I used a patched lilo version 21 from M-System. If I run lilo I get the
> message: Sorry don't know how to handle device 0x5d01.

Re: Booting from a DiskOnChip2000

[Russ Dill]

On Wed, 2002-04-24 at 05:28, Thomas Preisig wrote:
> Hi
> 
> I use a DiskOnChip 2000 and an Allwell Settopbox. I compiled the 2.4.18
> Linuxkernel with the MTD drivers.
> Mounting the DOC into the /mnt directory is no problem but now I've
> tried to install lilo on the DOC. I used a patched lilo version 21 from
> M-System. If I run lilo I get the message: Sorry don't know how to
> handle device 0x5d01.

use grub from CVS, works great. I have fsys_cramfs if anyone is
interested, I sent it to the grub people a while back, but haven't got
any replies

Re: Booting from a DiskOnChip2000

[John Sutton]

Hi there

I'm thrashing about also trying to boot from DoC.  I'm tempted to think that
I've nearly got there *without* having to go understand things like
GRUB/LinuxBIOS etc.  But *maybe* I'm completely deluding myself!  Perhaps
somebody can advise me...

Here's what I've got:

Two partitions on a 16Mb DoC:

Command (m for help): u
Changing display/entry units to sectors

Command (m for help): p

Disk /dev/nftla: 16 heads, 2 sectors, 998 cylinders
Units = sectors of 1 * 512 bytes

     Device Boot    Start       End    Blocks   Id  System
/dev/nftla1             2     23999     11999   83  Linux
/dev/nftla2         24000     31935      3968   83  Linux

I'm trying to boot a kernel held on partition 1 (I need partition 2 later on
but not for booting) so I've put the usual stuff on there - vmlinuz and boot.b. 
Then I mount /dev/nftla1 on /mnt and run LILO with this config:

---------------------------
boot=/dev/nftla
map=/mnt/boot/map
backup=/mnt/boot/boot.5D00
install=/mnt/boot/boot.b
prompt
timeout=20

disk=/dev/nftla
        bios=0x80
        sectors=2
        heads=16
        cylinders=998
        partition=/dev/nftla1
                start=2

image=/mnt/boot/vmlinuz
        label=linux
        append="no-hlt"
        read-only
        root=/dev/md2
---------------------------

And that "works" i.e. I've gotten rid of the "Sorry don't know how to handle
device 0x5d01" message and lilo -v says it has done the trick.  Sadly, however,
on booting all I get is a solitary "L" ;-(  Or, 2 L's on *seperate* lines
(weird, huh?) if I also use linear...

According to the lilo docs, this solitary L means there is some kind of
"geometry mismatch"...

If I mess about long enough with the lilo config, am I going to win?  Have
other people done this kind of thing?  Or am I completely misunderstanding what
is at stake and really *have to* look into GRUB/LinuxBIOS to have any chance of
booting a linux kernel off a DoC?

TIA
John

> Thomas,
> 
> I believe lilo can talk to devices by means of BIOS calls.  If I
> understand correctly, the M-Systems patch to lilo adds the mapping of the
> /dev/ftla (?) root device name to the appropriate BIOS disk number.
> 
> I infer from your description that you haven't made a complete choice
> between using the M-System's Linux driver and the MTD doc2000.c driver.
> 
> If you are going for M-System's driver, I think you may need to specify
> the correct device name (/dev/ftla ?) as a root device (and optionally as
> a boot device) in /etc/lilo.conf.
> 
> Then the lilo command should be able to write down the block numbers of
> the kernel image it needs to load at system startup.
> 
> If you are going for the MTD doc2000.c driver which doesn't attempt to
> emulate age old real mode BIOS API, then the bootloader will have to
> access the content of the NFTL layer by using a bootstrap driver similar
> to the kernel doc2000.c module.  
> 
> The MTD CVS repository contains the patch to the GRUB bootloader which
> performs the above bootstrap access.  As a bonus, the GRUB bootloader
> doesn't require any block numbers list to find the kernel image as it has
> the bootstrap drivers for the most of filesystems as well.
> 
> The latest DOC 2000 / Millennium patch is in CVS directory
> 
>         mtd/patches/grub-2002-02-19-doc.patch
> 
> You may need to download the source code of GRUB off its own CVS
> repository at
> 
>         http://savannah.gnu.org/projects/grub/
> 
> The copy of the DOC 2000 / Millennium patch can also be found in the Patch
> Area of the GRUB project.
> 
> Ilguiz
> 
> On Wed, 24 Apr 2002, Thomas Preisig wrote:
> 
> > I used a patched lilo version 21 from M-System. If I run lilo I get the
> > message: Sorry don't know how to handle device 0x5d01.


***************************************************
John Sutton
SCL Internet
URL http://www.scl.co.uk/
Tel. +44 (0) 1239 711 888
***************************************************

Re: Booting from a DiskOnChip2000

[Ilguiz Latypov]

John,

Sorry if I misunderstood you, but you installed the lilo bootloader into
DiskOnChip.  As you found, lilo needs BIOS disk number to talk to the 
device.  The same is true for GRUB as the latter doesn't have the IDE 
drivers built in.

The M-System's DiskOnChip is shipped with the BIOS driver programmed into
the flash memory.  The driver gets activated during BIOS initialization.  
The M-System's lilo usage model assumes that BIOS will attempt to load the
lilo image in the same way as BIOS would load the master boot sector off
the hard disk.  

The above startup scheme is possible because the M-System's drivers are
already hooked to the BIOS INT 13h disk access call when BIOS wants to 
load the first sector off the bootable medium.

So your attempt to load the kernel off DiskOnChip with lilo may succeed as
long as you keep the M-System's boot area of the flash chip intact.  I
think the problem with lilo you mentioned is due to different default BIOS
disk number/geometry specified by you and the configuration of the
M-System's driver.  You may need to consult M-System's documentation paper
on its MS-DOS-based formatting software.

Once the Linux kernel is started, accessing a filesystem installed on top
of NFTL layer can be possible by means of the M-System's Linux driver
*and* by the MTD doc2000.c/nftl.c drivers *but* not by both.

Ilguiz

On Wed, 24 Apr 2002, John Sutton wrote:

> disk=/dev/nftla
>         bios=0x80
>         sectors=2
>         heads=16
>         cylinders=998
>         partition=/dev/nftla1
>                 start=2

Re: Booting from a DiskOnChip2000

[John Sutton]

Hi Ilguiz

Many thanks for that - I'm now much clearer what I'm doing ;-)

And I've succeeded!  The problem was only that the standard lilo doesn't work
with DoC.  I hadn't realised until you mentioned it that M-Systems provide a
patched lilo on their web site!  I had just built a standard kernel (2.4.18)
with all the right bits enabled and thought that would be enough.  And it
is, apart from lilo...  Anyway, I've now downloaded M-System's patched lilo and
this works fine.  But it's worth noting that you still have to explicitly
specify the geometry in the lilo.conf file (as below), but that is not
difficult because everything you need to know is available just by running
fdisk on /dev/nftla.

Thanks again
John

On Wed, 24 Apr 2002, you wrote:
> John,
> 
> Sorry if I misunderstood you, but you installed the lilo bootloader into
> DiskOnChip.  As you found, lilo needs BIOS disk number to talk to the 
> device.  The same is true for GRUB as the latter doesn't have the IDE 
> drivers built in.
> 
> The M-System's DiskOnChip is shipped with the BIOS driver programmed into
> the flash memory.  The driver gets activated during BIOS initialization.  
> The M-System's lilo usage model assumes that BIOS will attempt to load the
> lilo image in the same way as BIOS would load the master boot sector off
> the hard disk.  
> 
> The above startup scheme is possible because the M-System's drivers are
> already hooked to the BIOS INT 13h disk access call when BIOS wants to 
> load the first sector off the bootable medium.
> 
> So your attempt to load the kernel off DiskOnChip with lilo may succeed as
> long as you keep the M-System's boot area of the flash chip intact.  I
> think the problem with lilo you mentioned is due to different default BIOS
> disk number/geometry specified by you and the configuration of the
> M-System's driver.  You may need to consult M-System's documentation paper
> on its MS-DOS-based formatting software.
> 
> Once the Linux kernel is started, accessing a filesystem installed on top
> of NFTL layer can be possible by means of the M-System's Linux driver
> *and* by the MTD doc2000.c/nftl.c drivers *but* not by both.
> 
> Ilguiz
> 
> On Wed, 24 Apr 2002, John Sutton wrote:
> 
> > disk=/dev/nftla
> >         bios=0x80
> >         sectors=2
> >         heads=16
> >         cylinders=998
> >         partition=/dev/nftla1
> >                 start=2
-- 

***************************************************
John Sutton
SCL Internet
URL http://www.scl.co.uk/
Tel. +44 (0) 1239 711 888
***************************************************