One of them is a hidden partition for system recovery. It's one of three methods of restoring the original Xandros install, according to the user manual. The other two methods are: using the included support DVD or creating a usb flash disk restore (if you don't have an external dvd drive...)-- interesting.

sda1 and sda2 are both used and mounted through unionfs on /
one of them is read only.
forgot about sda3
sda4 is /tmp (hope I did not mix up sda3 and sda4)

checked.
/dev/sda3 contains the bios image (701.rom)
I can't mount /dev/sda4 as there is no such entry in /dev
/dev/sda5 is not a valid block device

Hi

I have re read the article I quoted in my previous post, There is one paragraph that sticks out:-

Extensions to EFI can be loaded from virtually any non-volatile storage device attached to the computer. For example, an original equipment manufacturer (OEM) can sell systems with a hidden EFI partition on the hard drive which would add additional functions to the standard EFI BIOS stored on the motherboard's ROM. EFI can also provide a small shell environment; rather than booting directly into a full OS, the user can boot to an EFI shell. This is an optional intermediate step in the booting process which can be used to run diagnostic or configuration utilities, or even play CDs or DVDs without a complete operating system.

In another post I was whining on about  whether and how the EEEPS performs a restore from the provided CD, I was told it was an image copy, but that still begged the point  of how the EEEpc bootstrapped itself.  I believe that the EEEPC uses the EFI system to bootstrap itself to rebuild the ext2fs partitions, though I could be wrong, I generally am!

cheers

Patrick

Last edited by superpat (2007-10-31 6:47:36 am)

mmm Ye that could be disaster if some n00b goes lets install windows. And decides to go for the wipe and start again.

But surly this can not be the case...

Well, here's a question then.  When you set "installing new OS" or whatever it is in the Bios before installing a new OS, what do these partitions look like?  Does the BIOS protect them (ie, they disappear)?  If so, that would be a good case for not deleting them. 

Sorry I can't answer this myself.  My eee doesn't arrive until tomorrow.

The manual tells you to delete all partitions when installing windows.  It seems that if you don't delete all partitions, the bios partition remains the bootable one and windows won't boot.  Can anyone confirm we should indeed delete all partitions as the manual says.

So if the BIOS still works after deleting all partitions, why are sda3 and sda4 present in he original setup ? According to menu.lst, the bootloader is installed in the first partition.

Could you post the partition table as seen by windows ? Are all 486 cylinders combined into one large partition or are two cylinders (the former sda3 and sda4) still missing ?

@engineer

Hi

I think you are correct.  I also have looked and Googled for any reference to a separate Bios chip on the EEEPC m/b. I cannot find one either.  It makes engineering sense there as there is a 2GB+ (dep on model) of flash memory on board then use it to hold the BIOS.  I am sure that the SSD control chip (SM223) is quite capable of making the last two blocks read only when commanded to for that purpose.

It would be instructive to dissemble the ASUS Bios updater utility and see what IO commands it does. ( is the SM223 wired up to the GPIO bus? )

Unfortunately the Silicon Motion company that makes the SM223 are very close with the details of their chip and the capabilities. However if you have a look at  www.nextwarehouse.com/DS/iERP/ATA_SMB_DMA.pdf .

This is a data sheet for an ATA flash card that uses the Silicon Motion SM222 chip (similar to the SM223), There are pages and pages of control register details there. I know its not exactly the same but it does give you some idea how powerful the SM223 is!

I am still unclear why there are two partitions for the BIOS and the EFI. Windows XP does not support EFI, however the Intel 950 chip set does, the EFI article I read said it was disabled at this time.  Perhaps the EFI apartition is for future expansion.

However I may be wrong as usual,  Has anyone seen a BIOS CHIP on the eeepc motherboard ????

regards

Patrick

Qatz wrote:

If you want to try mounting the efi to see whats in it, you could try "mount -t vfat /dev/sda4 /mnt/sda4" being that the efi fs is based on fat it may work.
*note if there is no /dev/sda4 you will have to do a "mknod" to add it. Look here "http://linux.die.net/man/4/hd" for more details.

did the mknod, but the mount fails
dmesg says: bogus number of resevered sectors
and:  can't find a valid FAT filesystem on /dev/sda4

so most likely it is in the partition table, but it is just empty and not formatted

eFfeM wrote:

did the mknod, but the mount fails
dmesg says: bogus number of resevered sectors
and:  can't find a valid FAT filesystem on /dev/sda4

so most likely it is in the partition table, but it is just empty and not formatted

Hmmm sounds like the node wasn't made right try "dd if=/dev/sda4 of=sda4.bin" this will write a file called sda4.bin in your working dir. It should be a clone of the sda4 partition(Which you can mount via loopback) if it gives you an error message or produces a file with a size of 0, then the node is faulty.

The efi partition is normally used on linux and mac machines. Often it will contain things like your boot loader, diagnostic apps, kernels, and restore software. Its simply pre-os goodies that are more advanced then the standard bios itself. In most cases its just a partition at the beginning of your hard disk. However is some circumstances it can be a chip thats read only. In the case of linux based os's its normally just a fat partition containing a boot loader and or kernels. What I suspect is that the eeepc supports the efi specification, but they don't want you playing with it so they provide no node to it. As to what sda3 is used for I have no clue I will just have to wait for UPS to drop off my EEEPC(sigh shipped ground from Texas to Maine)