Re: [PATCH] net: stmmac: Wait a bit for the reset to take effect

From: Bernd Edlinger
Date: Fri Nov 03 2023 - 06:45:14 EST




On 11/2/23 12:25, Paolo Abeni wrote:
> On Mon, 2023-10-30 at 07:01 +0100, Bernd Edlinger wrote:
>> otherwise the synopsys_id value may be read out wrong,
>> because the GMAC_VERSION register might still be in reset
>> state, for at least 1 us after the reset is de-asserted.
>>
>> Add a wait for 10 us before continuing to be on the safe side.
>
> This looks like a bugfix: you should target explicitly the 'net' tree,
I dont understand, did you mean to add "net:" to the subject?
It is already "net: stmmac: ..." or did you mean to send this message to
another mailing list?

> adding such tag into the subj. More importantly you should include a
> suitable 'Fixes' tag.
>

You mean an informal description of what this fixes?
like
Fixes: Randomly occurring "Version ID not available" messages.

Or do mean to pick a commit where the error was introduced? I doubt
I am able to do the necessary bisection steps, as this seems like an
issue that was introduced by the initial design. And I also doubt that
it can only affect the GMAC_VERSION register.
To make that clear, the issue is totally harmless, maybe some performance
degradation but I became aware of it only because I was trying to solve
a totally different issue, and therefore I have looked very closely at the
printk messages, so I spotted the anomaly to tracked it down the reason for
this flaw.

Thanks
Bernd.

> Please send a new revision with the above changes. You can retain the
> already collected reviewed tags.
>
> Thanks,
>
> Paolo
>