Glad to hear you got it working :) The confusion is due to the fact
that the first versions of the bifferboard shipped with the kernel
command line pre-set to use a USB rootfs. So all the instructions that
were written at the time didn't bother explaining that the command
line needed to be set.
But then Biff got OpenWRT working from flash, so he removed the
'default' command line in BiffBoot, and embedded the command line
inside the openwrt kernel.
But of course in order to follow "older" instructions (Slackware or
Debian), you need to set/change the kernel command line to what it
used to be.
And to find out what the command line used to be, you can look at the
> IMPORANT: Debain on the Bifferboard is not possible without the use of
> a serial cable!
It wasn't a personal criticism - I'm also guilty of not updating my
Slackware instructions yet...
> Lurch, what do we need to set the "Boot source" using
> "bb_eth_setconfig.py" - set it from the default "Flash" to "MMC" (in
> order to boot from USB) ?
The Boot source is where it loads the kernel from - so you need to set
it *always* to Flash. The MMC setting is only if you're doing
Where the rootfs is loaded from (i.e. USB for Debian and Slackware),
is controlled entirely by the kernel (and/or the kernel command line).
But again "boot source" determines kernel location, not rootfs. For
the 2-port bifferboards, if the MMC/SD slot is used it just appears as
another USB Mass Storage device, and disables one of the USB ports.
I don't think Biffboot actually knows anything about USB (?)
> 2. The new thing is that the "Kernel cmndline" is now different,
> right? Is it empty or what?
See the 'screenshots' on
a complete(-ish) list of all the default config options on the
different BiffBoot versions.
> 3. How should I re-compile the Debian Linux kernel now? With the
> 4. (this depends on #2) Should I completely override the kernel string
> 5. Or should I just leave the kernel as it is, and ask people to fix
Entirely up to you, I guess :)
Whichever way you do it, you can guarantee different people will be
using different Biffboot versions (and therefore different default
I'm not sure of the specifics (as it's something I've not played with)
but apparently sometimes the command-line set in biffboot can
'interfere' with the command-line embedded in the kernel.
> 6. What did the "usbroot" magic command did in Biffboot, as described
> by Martin? He says that fixed it all. The command "usbroot" just
> updated the kernel command line in Biffboot to the old default value -
> "console=uart,io,0x3f8 root=/dev/sda1 rootwait ro"?
I don't have any bifferboards flashed to that kernel version ATM, but
I can check later if you like (if Biff doesn't beat me too it!)
I don't recall any Biffboot versions ever setting the rootfs readonly?
> Thanks. And sorry for all the questions...
No problem :)
How hard would it be to just provide two kernels? A "newbie" kernel
which has a hard-coded embedded command line (and therefore works with
all biffboot default versions) and an "expert" kernel that reads the
command line from Biffboot?
Obviously the rootfs for each kernel would be the same...