Re: [RFT] ath10k: restart fw on tx-credit timeout

[Ben Greear <greearb@candelatech.com>]

On 02/08/2015 10:24 PM, Michal Kazior wrote:
> On 6 February 2015 at 17:15, Ben Greear <greearb@candelatech.com> wrote:
>> On 02/06/2015 04:05 AM, Michal Kazior wrote:
>>>
>>> It makes little sense to continue and let
>>> firmware-host state become inconsistent if a WMI
>>> command can't be submitted to firmware.
>>>
>>> This effectively prevents after-affects of
>>> tx-credit starvation bug which include spurious
>>> sta kickout events and inability to associate new
>>> stations after some time when acting as AP.
>>>
>>> This should also speed up recovery/teardown in
>>> some cases when firmware stops responding for some
>>> reason.
>>
>>
>> I have not seen a WMI timeout since I added keep-alive
>> and CE polling in my firmware, but the patch looks OK
>> to me.
>
> This is mainly aimed at the tx-credit starvation due to mgmt-tx being
> stuck on client powersave buffering.
>
>
>> You might add something about 'WMI' in that warning
>> message to make it more clear what is not being
>> responsive.
>
> Good point.
>
>
>> At least in my tests, I could continue
>> to receive network traffic while WMI was blocked.
>
> Yeah. Traffic works with the tx-credit starvation as well but what
> good is this if you have inconsistent driver-firmware state after
> failing to send a few commands?

I just mention it because someone debugging the system might
wonder why the firmware is 'locked up' while it is still passing traffic.

I agree with your patch in general.

If it is just powersave issue, could you force (overriding wmi tx-credits limit)
a flush at the 1 second mark and hope it recovers by 3 second timeout?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com