FreeBSD 12.1-BETA3 won't boot on Beaglebone Black

[Ian Lepore]

On Tue, 2019-10-08 at 17:12 +0000, Glen Barber wrote:
> On Tue, Oct 08, 2019 at 05:04:06PM +0000, Mark Linimon wrote:
> > On Tue, Oct 08, 2019 at 03:34:17PM +0000, Glen Barber wrote:
> > > I have seen issues with some SD cards on a few different SoCs
> > > where
> > > certain classes (i.e., 4) are too slow for some boards, and
> > > higher
> > > classes (i.e., 10) are too fast for others.
> > 
> > ew.  We should document this somewhere.  The potential for users
> > shooting themselves in the feet is too high.
> > 
> 
> The "problem" with documenting this (or, at least me documenting it)
> is
> I have seen very inconsistent behavior.  But if someone(tm) can
> reliably
> reproduce test cases with various SD card classes, yes, I agree it is
> something that would be highly beneficial to have documented.
> 
> Glen
> 

The problem this mail thread is talking about has nothing to do with sd
cards, sd card classes or anything vaguely related to that, because
it's about the eMMC on the board, not sd cards.

I personally believe this whole sd card classes thing is a red herring.
Some cards work better than others in noisy-signal environments.  That
has nothing to do with card classes.  I also see people blame
manufacturers or brands inappropriately.  When there is a reproducible
problem at all, it tends to be with a specific model of card, but in my
experience, even that is very rare.

-- Ian