Long delays for USB realbtx boot

Bruce M Simpson bms at incunabulum.net
Thu Sep 11 15:49:59 UTC 2008

[Ccing to list to track up thread]

Douglas Berry wrote:
> Perhaps this doesn't help...  I do RELENG_7 based images
> for USB keys/CDROM using the FreesBIE toolkit, and haven't
> noticed such delays.  I do fill the stick 'tho.  Here's
> fdisk output...
> ******* Working on device /dev/md4 *******
> parameters extracted from in-core disklabel are:
> cylinders=62 heads=255 sectors/track=63 (16065 blks/cyl)

Interesting, that's classic USB-HDD geometry (255H, 63S).
Can you tell me what make, model of stick this is?

It could be that the cylinder change is what's confusing the BIOS. I 
will need to do some tweak to make sure the cylinder calculation is 
right for the stick's capacity.

The A/Open MX3S has no USB-HDD mode. It appears to have the same delay 
issue, however, it didn't see any difference between the USB-HDD 
geometry image and the USB-ZIP geometry image.

empiric:~/shelf/chipdocs/aopen % camcontrol inquiry da0
pass1: <Kingston DataTraveler 2.0 PMAP> Removable Direct Access SCSI-0 
pass1: Serial Number
40.000MB/s transfers
empiric:~/shelf/chipdocs/aopen % camcontrol readcap da0
Last Block: 1953791, Block Length: 512 bytes

That device uses USB-ZIP style geometry (64H, 32S), and based on the 
"last block", 1953792 / 2048 is 954 cylinders exactly, which is how it 
came factory formatted.

So I should probably give it a shot based on this. To get something up 
and running I've been using generic methods in the NanoBSD patch, I 
haven't sized the MBR geometry specifically to the device.

By my reckoning your stick is just under 512MiB, based on the geometry 
you provided:
> parameters to be used for BIOS calculations are:
> cylinders=62 heads=255 sectors/track=63 (16065 blks/cyl)
> Media sector size is 512
> Warning: BIOS sector numbering starts with sector 1
> Information from DOS bootblock is:
> The data for partition 1 is:
> sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
>     start 32, size 1001440 (488 Meg), flag 80 (active)
>         beg: cyl 0/ head 1/ sector 1;
>         end: cyl 488/ head 63/ sector 32
> The data for partition 2 is:
> The data for partition 3 is:
> The data for partition 4 is:


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