cvs commit: src/sys/dev/bge if_bge.c if_bgereg.h

[Bruce Evans]

On Wed, 13 Dec 2006, Bjoern A. Zeeb wrote:

> On Tue, 12 Dec 2006, Scott Long wrote:
> [..]
>> I'll try to run some tests with the third write disabled, but I don't have 
>> much time left to devote to this particular project.  If others would be 
>> willing to test with the third write removed, I'd appreciate it.  It might 
>> be interesting to test with the second write removed as
>> well (i.e. both writes in bge_reset).  I'll post patches if anyone wants
>> to test but can't grok what I'm saying here.
>
> ok, I only tried with the two writes removed from bge_reset and it
> started to work again. At least the machine no longer hangs on boot
> and the first bge port works. Cannot easily test more atm.

I'm getting closer to testing with various numbers of writes together
with optionally waiting for the firmware to indicate sync by complementing
the value.  Maybe the problem is just that the firmware doesn't like
the value being set without syncing with the previous setting.

While editing, I noticed that the first write (in bge_sig_pre_reset())
is already avoided except in asf mode because "Some chips don't like
it".  Someone named scottl may have already been bitten by this.  He
added a tunable to kill the default of asf mode being enabled, since
leaving it enabled gave a complete system freeze for the same operation
that now freezes on the third write.

Bruce