Code review request: boards on AT91

[M. Warner Losh]

In message: <20081125234656.e1820a12.stas at FreeBSD.org>
            Stanislav Sedov <stas at FreeBSD.org> writes:
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: On Tue, 25 Nov 2008 13:00:21 -0700 (MST)
: "M. Warner Losh" <imp at bsdimp.com> mentioned:
: > 
: > So long as it is optional.  The KB9202 boards that I have don't have
: > room for uboot or redboot.  You have 16kb of space, which boot2 fits
: > nicely into right now (clocking in at about 9.5k).
: >
: 
: Have it got parallel or SPI flash? My board boots u-boot directly
: from parallel flash on start.

Not really.  While the Kwikbyte board I have does, the board that was
developed for my last company doesn't really have it on there.  I
believe it was cost reduced off the board since we didn't need it: the
iic boot loader could load the kernel directly off of the SD card.

: > : > but there's a fair number of different boot loaders today for
: > : > FreeBSD/arm.  While it would be nice to mandate all the world use
: > : > uboot + /boot/loader, that's not likely going to happen.  There's too
: > : > many boards out there that have redboot or some custom boot loader
: > : > that will be hard to replace...
: > : 
: > : In that cases loader(8) could be used.
: > 
: > Not always.  That's the point that I keep coming back to.  There's no
: > easy way to make loader read things from disks, over the network, etc
: > in the embedded space.  Right now for some uboot based systems, this
: > can be done, but for redboot systems, you are basically out of luck.
: > There's no way that loader(8) can load additional sections without a
: > lot of board specific code.
: > 
: 
: I see your point. If there's no room for extending/replacing you
: have to live with what the board has:-(

Yes.  Sadly, we're not in a position of saying you must have
boatloader X.  I wish we were...

Warner