Re: [RFC net-next] net: stmmac: should not modify RX descriptor when STMMAC resume

[Florian Fainelli <f.fainelli@gmail.com>]

On 4/22/2021 11:18 AM, Jon Hunter wrote:
> 
> On 22/04/2021 18:32, Florian Fainelli wrote:
>>
>>
>> On 4/22/2021 10:00 AM, Jon Hunter wrote:
>>>
>>> On 22/04/2021 17:12, Florian Fainelli wrote:
>>>
>>> ...
>>>
>>>> What does the resumption failure looks like? Does the stmmac driver
>>>> successfully resume from your suspend state, but there is no network
>>>> traffic? Do you have a log by any chance?
>>>
>>> The board fails to resume and appears to hang. With regard to the
>>> original patch I did find that moving the code to re-init the RX buffers
>>> to before the PHY is enabled did work [0].
>>
>> You indicated that you are using a Broadcom PHY, which specific PHY are
>> you using?
>>
>> I suspect that the stmmac is somehow relying on the PHY to provide its
>> 125MHz RXC clock back to you in order to have its RX logic work correctly.
>>
>> One difference between using the Broadcom PHY and the Generic PHY
>> drivers could be whether your Broadcom PHY driver entry has a
>> .suspend/.resume callback implemented or not.
> 
> 
> This board has a BCM89610 and uses the drivers/net/phy/broadcom.c
> driver. Interestingly I don't see any suspend/resume handlers for this phy.

Now if you do add .suspend = genphy_suspend and .resume = bcm54xx_resume
for this PHY entry does it work better?
-- 
Florian