DWC OTG TX path optimisation for 11-current

[Andreas Schwarz]

On 15.08.15, Hans Petter Selasky wrote:
> On 08/09/15 05:09, Andreas Schwarz wrote:
>> On 31.07.15, Hans Petter Selasky wrote:
>>
>> I've applied the patch to r286117 and started to build the world in a
>> loop until the problem occur. See the output below. After the problem
>> was there (last lines), no further debug output was generated by your
>> patch.
>
> Can you re-test the latest 11-current after:
>
> https://svnweb.freebsd.org/changeset/base/286802

I made an extensive test the whole last week. I updated the system to 
r286833 and started to build the world in a loop. 

root at pizelot:/usr/src # cat loop_build.sh
#!/bin/sh

while true
do
  make cleandir
  make -j4 kernel-toolchain
  make -j4 buildkernel
  make -j4 buildworld
  date >> loop_build.log
done


I've tested two kernels, a custom kernel with INVARIANTS disabled and the default 
RPI2 kernel.

With both kernels I was not able to reproduce the initial problem. Nevertheless,
both attempts end with a crash and reboot (after several loops). The custom kernel 
crash after one day, the default RPI2 kernel after 5 days and (6 rounds completed). 
I've no further data related to these crashes, I don't think that it has to do with 
with our problem.

The used SD Card was a "Samsung SDHC 32 GB C10 UHS-1 MB-MGBGB".

-asc