Grub Booting Disk On Chip

[Ilguiz Latypov]

Bob,

On 30 May 2002, Bob Chiodini wrote:

> root (dc0,0)
> configfile /boot/grub/menu.lst
> 
> At this point a get a menu with the second entry highlighted.  Hitting
> enter boots from /dev/hda1.  /dev/hda1 is the only disk on the system.

Does GRUB show unsuccessful attempts to load /boot/grub/menu.lst from the 
disk 0xE0 before going to interactive mode?  

Also, the fact that menu.lst is a symbolic link could confuse the stripped
down ext2 filesystem driver of GRUB.  Can you remove the link and create a 
regular configuration file?

> It looks like DS is saved as the address of the DOC, if it is not a
> Millenium DOC.

Oops, you are right.  In fact, the read-only initial program loader of DoC 
2000 will copy the firmware from the flash memory to 0x2000:0 before 
jumping there with the DS segment pointing to the DoC BIOS window.  Here 
is the David's comment in the patch:

        * With DoC 2000, _start is loaded at 0x20000 by the IPL,
        * and is jumped to with CS:IP 0x2000:0, DS is <DoC segment>.

Later DS is stored in %cs:doc_seg where %cs holds the segment at the end
of conventional RAM.

Ilguiz