lkml.org 
[lkml]   [2022]   [Oct]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH net] net: phy: Avoid WARN_ON for PHY_NOLINK during resuming
From
Date
Hi Heiner,

Thank you for your comment.

On 2022/10/21 17:38, Heiner Kallweit wrote:
> On 21.10.2022 09:41, Kunihiko Hayashi wrote:
>> When resuming from sleep, if there is a time lag from link-down to link-up
>> due to auto-negotiation, the phy status has been still PHY_NOLINK, so
>> WARN_ON dump occurs in mdio_bus_phy_resume(). For example, UniPhier AVE
>> ethernet takes about a few seconds to link up after resuming.
>>
> That autoneg takes some time is normal. If this would actually the root
> cause then basically every driver should be affected. But it's not.

Although the auto-neg should happen normally, I'm not sure about other
platforms.

>> To avoid this issue, should remove PHY_NOLINK the WARN_ON conditions.
>>
>> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
>> ---
>> drivers/net/phy/phy_device.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
>> index 57849ac0384e..c647d027bb5d 100644
>> --- a/drivers/net/phy/phy_device.c
>> +++ b/drivers/net/phy/phy_device.c
>> @@ -318,12 +318,12 @@ static __maybe_unused int mdio_bus_phy_resume(struct
>> device *dev)
>> phydev->suspended_by_mdio_bus = 0;
>>
>> /* If we managed to get here with the PHY state machine in a state
>> - * neither PHY_HALTED, PHY_READY nor PHY_UP, this is an indication
>> - * that something went wrong and we should most likely be using
>> - * MAC managed PM, but we are not.
>> + * neither PHY_HALTED, PHY_READY, PHY_UP nor PHY_NOLINK, this is an
>> + * indication that something went wrong and we should most likely
>> + * be using MAC managed PM, but we are not.
>> */
>
> Did you read the comment you're changing? ave_resume() calls phy_resume(),
> so you should follow the advice in the comment.

I understand something is wrong with "PHY_NOLINK" here, and need to investigate
the root cause of the phy state issue.

Thank you,

---
Best Regards
Kunihiko Hayashi

\
 
 \ /
  Last update: 2022-10-21 11:35    [W:0.050 / U:1.532 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site