Re: BCM4313 & brcmsmac & 3.12: only semi-working?

On 27-08-14 17:27, Arend van Spriel wrote:

On 08/27/14 12:02, Michael Tokarev wrote:

quoted

27.08.2014 01:37, Arend van Spriel wrote:

quoted

On 08/26/14 18:15, Michael Tokarev wrote:

[]

quoted

Well, sorry about that. I did see the other messages fly by and
noticed you were using the wl driver so assumed you were fine with that.

That's past already.  I had several issues with wl driver,
and current issue is that even the latest (Aug-2014) version
of wl driver doesn't work with current kernel.  So I can't
really even compare wl and brcmsmac, -- in kernels<  3.16
brcmsmac does not work, but wl can't be compiled for 3.16,
and using different kernels for comparison is a bit wrong
because there may be differences in other areas.

quoted

    Admittedly the brcmsmac got very little attention as all our
resources were put on brcmfmac.

That happens. :)

[]

quoted

Ok. Let's put frustration aside and make an effort. So could you make
a trace using trace-cmd utility. The log can get quite big. The
brcmsmac driver needs to be built with CONFIG_BRCM_TRACING enabled.
Please execute the following commands (assuming you use ubuntu with
network-manager):

$ sudo stop network-manager
$ sudo insmod brcmfmac.ko
$ sudo trace-cmd record -e brcmsmac:*

In another terminal:

$ sudo start network-manager

The trace-cmd must be stopped using ctrl-c.

Okay.  This turned out to be not so simple.

My initial attempt indicated that brcmsmac in 3.16 does
not work at all.  This isn't actually true - subsequent
attempts shows that it works.  I was ready to conclude
the problem is fixed (after transferring several gigs
of data over wifi, with tracing enabled or disabled,
after fresh boot or after reboot from wl-enabled kernel,
etc - it all worked.

Until I hit the same stall as I described initially, the
same which happened numerous times with kernel 3.12 ($subj).

After several mins of transferring it stalled.  But this
time (unlike with 3.12), it continued after about 30 secs.

A kernel log (so no trace) of stalling interface might be useful so if
you can provide that and put a marker in there where you believe it
stalled that would be great.

Hi Michael,

Did you have any opportunity to create a log file. Got a question from
someone else who got bad bcm4313 behaviour after a certain upgrade. Did
you have the same experience?

Regards,
Arend

quoted

So, while my initial test of 3.16 indicated the prob is still
here, at the same (or even worse) state, I can't really
reproduce it, at least in a reliable way.  There's something
wrong still, but at least current version is significantly
more useful than before (in a hope it wont stall at the
very wrong moment exactly ;).

There's one more difference between brcmsmac and wl -- with
wl, I see significantly better speed, -- it is about 5MB/sec,
while with brcmsmac it jumps between 2.0..4.5MB/sec (with
58..65Mbps connection rate in both cases).  Here's a typical
iwconfig output for brcmsmac version:

wlan0     IEEE 802.11bgn  ESSID:"mjt"
           Mode:Managed  Frequency:2.412 GHz  Access Point:
64:70:02:29:D9:30
           Bit Rate=65 Mb/s   Tx-Power=19 dBm
           Retry short limit:7   RTS thr:off   Fragment thr:off
           Power Management:off
           Link Quality=58/70  Signal level=-61 dBm
           Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
           Tx excessive retries:56355  Invalid misc:472   Missed beacon:0

I'll keep trying/testing various cases, in attempt to
understand what's going on.  For now, I can't provide the
requested traces (it wont be very useful, I guess).

BTW, are there other things not implemented in brcmsmac?
I see the module reminds about power management, what
does it mean?  Anything else missing?

Well, the wireless twiki has that info [1]. Regarding features the
important ones that I know are still not there are 40MHz support, and
power-save. The bcm4313 does not support 40MHz. Community contributions
added ibss, and ap mode. For P2P and TDLS probably some changes would be
needed although most of the legwork is done in mac80211.

Regards,
Arend

[1]
http://wireless.kernel.org/en/users/Drivers/brcm80211#To_be_done_for_softmac_driver

quoted

Thank you!

/mjt