RE: [PATCH v7 3/5] Add debugfs based silicon debug support in DWC

[Shradha Todi]

> -----Original Message-----
> From: 'Krzysztof Wilczyński' <kw@xxxxxxxxx>
> Sent: 05 March 2025 13:15
> To: Shradha Todi <shradha.t@xxxxxxxxxxx>
> Cc: 'Geert Uytterhoeven' <geert@xxxxxxxxxxxxxx>; 'Fan Ni' <nifan.cxl@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-
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> Subject: Re: [PATCH v7 3/5] Add debugfs based silicon debug support in DWC
> 
> Hello,
> 
> > I think we shouldn't move the log level to be a WARN. I believe many
> > controllers might not support RAS DES feature in their design and
> > giving a warn dump would draw unnecessary attention.
> 
> There will be no backtrack printed with neither dev_err() nor dev_warn(), which is what we were using here.  Using dev_WARN() or
> the WARN() macro directly would be an overkill in this case, indeed.
> 

Oh sorry, I thought we were talking about WARN() here.

> > My opinion is to silently let it fail unless the user is actually
> > interested in getting the RAS DES feature up.
> 
> I think, what we have there now is fine.  We don't error on the lack of RAS DES capability when the platform does not support it,
and
> only return an error following a memory allocation failure, which should ideally never happen.
> 
> That said, have a look at the following:
> 
>   https://web.git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/log/?h=controller/dwc
> 
> This is how the code looks like at the moment.
> 
> We can still move it to dev_dbg(), so basically suppress any errors or warnings from being printed outside of the debug log level,
if you
> think it would be better.
> 

No, the current version looks perfect. Thanks!

> Thank you!
> 
> 	Krzysztof