Hi, I've saw some devs talking about what's the best ARM board to work
on ports and the problems of our armv7 platform. I don't want other devs
(and users) wasted their limited money on useless hardware, so I'll
write some advices learned from my little experience with the platform.

ARM on OpenBSD
==============

ARM is a slow arch. Deal with this. The future won't be better because
the big ARM players are only really interested in the GPU performance.

OpenBSD/armv7 uses "softfp". ARM has three different "flavors" to work
with floating point numbers. The traditional "soft" flavor doesn't use
the FPU. "softfp" adds additional code to check if the system has FPU or
not. "hard" uses always the FPU and you can select at compilation time
the type of FPU.

"softfp" is very slow. The checks slow the code a lot. The problem is
OpenBSD can't change to a modern "hard" flavor because we need also a
"modern" version of binutils.

What board to buy?
==================

I bought a BBB and this hasn't been a good decision. The BBB doesn't
support SATA or USB (yet), so this board isn't recommended for porters.
The microsd cards are a big crap, these cards are good for linear
read/write (i.e. recording video) but are horrible working with random
read/write.  Don't think "softdep and buffercache can help" because
you're wrong. And NFS... well, no comments.

So, buy a board with SATA or USB support because your big problem will
be the I/O. The CPU isn't important because all of them are pretty slow.
Don't forget buy the serial cable and a very good power transformer
(some boards doesn't work perfectly without a good power source).

Recommmended internet sites
===========================

Our arm@ list. The arm list of netbsd and freebsd. Debian has a bunch of
of good resources about ARM and FPU in the wiki.

The git repo of u-boot is also interesting (denx.de/wiki).

Follow the development of the Linux distro of your board.

Cheers!.

-- 
Juan Francisco Cantero Hurtado http://juanfra.info

Reply via email to