More than one ath10k NIC will not load (bisected)

[Ben Greear]

On 01/22/2015 10:43 PM, Michal Kazior wrote:
> On 22 January 2015 at 22:08, Ben Greear <greearb at candelatech.com> wrote:
>>
>> On 01/21/2015 11:47 AM, Ben Greear wrote:
>>> On 01/21/2015 11:01 AM, Ben Greear wrote:
>>>> On 01/20/2015 06:49 PM, Ben Greear wrote:
>>>>> On 01/20/2015 06:13 PM, Sebastian Gottschall wrote:
>>>>>> Am 20.01.2015 um 22:53 schrieb Ben Greear:
>>>>>>> I tried running a patched version of 3.19.0-rc5 kernel, and it seems to work
>>>>>>> fine when there is one ath10k NIC in the system, but when there is two it
>>>>>>> doesn't try to load the firmware.
>>
>> Ok, this bisects to this commit.  First (or sometimes second) NIC will load,
>> but the other one will not load firmware.  No obvious errors in dmesg.
>
> So I'm confused. If it doesn't load firmware then there has to be some
> error in dmesg. If there are no errors then how come you know it
> doesn't load firmware? Is it being probed at all?
>
>
>> Platform is x86-64, Fedora 20.  NICS:
>>
>> 03:00.0 Network controller: Qualcomm Atheros QCA988x 802.11ac Wireless Network Adapter
>> 04:00.0 Network controller: Qualcomm Atheros QCA988x 802.11ac Wireless Network Adapter
>>
>>
>> 7c0f0e3c9797e5a08d15da68812f24eadaf9e82b is the first bad commit
>> commit 7c0f0e3c9797e5a08d15da68812f24eadaf9e82b
>> Author: Michal Kazior <michal.kazior at tieto.com>
>> Date:   Mon Oct 20 14:14:38 2014 +0200
>>
>>      ath10k: mask/unmask msi fw irq
>>
>>      This was the final missing bit to making sure the
>>      device doesn't assert interrupts to host.
>>
>>      This should fix possible race when target crashes
>>      during driver teardown.
>>
>>      This also removes an early warm reset workaround
>>      during pci probing.
>>
>>      Signed-off-by: Michal Kazior <michal.kazior at tieto.com>
>>      Signed-off-by: Kalle Valo <kvalo at qca.qualcomm.com>
>>
>> :040000 040000 f7ab5ff9f7e3713118dab6f23d02f11003de6fef fa5cb5ee76bdee2c654fcb8e6b8b1283c225bcc2 M      drivers
>
> Hmm.. This removes warm_reset in probe function but I fail to see how
> this could end up not loading one of the NIC *silently*?
>
> Anyway there's a pending patch which adds the reset back:
> https://github.com/kvalo/ath/commit/bdcd6f4e4ac5d2d2a56da4813f56655e6db0ee45
> . You might want to try it and see if it helps.

Reverting the patch made it work again for me.

I don't understand that code well, but perhaps you are disabling
a shared interrupt that silently stops the second NIC from
being able to do it's thing?

Do you have a PC with 2 NICs in it that you could try yourself?

I can grab you the logs of a failure to boot later today.

Thanks,
Ben

>
>
> Michał
>

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