[PATCH 0/1][SRU][H/OEM-5.13/OEM-5.14/U] UBUNTU: SAUCE: Fix invalid MAC address after hotplug tbt dock

[Aaron Ma]

On 9/10/21 1:12 PM, Kai-Heng Feng wrote:
> On Wed, Sep 8, 2021 at 8:40 PM Aaron Ma <aaron.ma at canonical.com> wrote:
>>
>>
>> On 9/8/21 8:06 PM, Tim Gardner wrote:
>>>
>>> Ick. It seems like there ought to be a more deterministic way to note when the MAC address has been copied. Why not a loop that does an msleep(1) until the MAC is address is updated or 600 msec elapses ?
>>
>> The MAC address of dock will read out at first, after 600 msec the MAC in BIOS will be updated.
>> Driver doesn't know which one is the right MAC address. This allows enough time for hardware to update the
> 
> According to [1], there _can_ be IRQ raised when MAC update is
> completed. So it's a good idea to check it.
> If there's no IRQ from FW at current stage, then this is an unpleasant
> but necessary workaround.
> 
> [1] https://lore.kernel.org/netdev/20daa122-aaec-0c6b-23f5-d2be2fcab1e9@intel.com/
> 

In current fw, no such irq.

Aaron

> Kai-Heng
> 
>>
>> MAC address.
>>
>> Aaron
>>
>>>
>>> On 9/8/21 2:49 AM, Aaron Ma wrote:
>>>> BugLink: https://bugs.launchpad.net/bugs/1942999
>>>>
>>>> SRU justification:
>>>>
>>>> [Impact]
>>>> igc driver can not connect to network after re-plugin thunderbolt dock
>>>> when
>>>> MAC passthrough enabled in BIOS.
>>>>
>>>> [Fix]
>>>> Wait for the MAC copy of BIOS when enabled MAC passthrough.
>>>> Intel engineer wants a different solution and promise to discuss with
>>>> firmware engineer.
>>>> Due to the schedule, made this as a short term solution to fix the
>>>> issue, and wait for the other
>>>> fix from Intel.
>>>>
>>>> [Test]
>>>> Verified on hardware, after hotplug the thunderbolt cable,
>>>> Ethernet works fine.
>>>>
>>>> [Where problems could occur]
>>>> It may break the igc driver.
>>>>
>>>> Aaron Ma (1):
>>>>     UBUNTU: SAUCE: igc: wait for the MAC copy when enabled MAC passthrough
>>>>
>>>>    drivers/net/ethernet/intel/igc/igc_main.c | 3 +++
>>>>    1 file changed, 3 insertions(+)
>>>>
>>>
>>
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