RE: [PATCH v6 0/4] Add support for debugfs based RAS DES feature in PCIe DW

[Shradha Todi]

> -----Original Message-----
> From: Niklas Cassel <cassel@xxxxxxxxxx>
> Sent: 19 February 2025 23:16
> To: Shradha Todi <shradha.t@xxxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; manivannan.sadhasivam@xxxxxxxxxx; lpieralisi@xxxxxxxxxx;
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> Subject: Re: [PATCH v6 0/4] Add support for debugfs based RAS DES feature in PCIe DW
> 
> On Fri, Feb 14, 2025 at 04:20:03PM +0530, Shradha Todi wrote:
> > DesignWare controller provides a vendor specific extended capability
> > called RASDES as an IP feature. This extended capability  provides
> > hardware information like:
> >  - Debug registers to know the state of the link or controller.
> >  - Error injection mechanisms to inject various PCIe errors including
> >    sequence number, CRC
> >  - Statistical counters to know how many times a particular event
> >    occurred
> >
> > However, in Linux we do not have any generic or custom support to be
> > able to use this feature in an efficient manner. This is the reason we
> > are proposing this framework. Debug and bring up time of high-speed
> > IPs are highly dependent on costlier hardware analyzers and this
> > solution will in some ways help to reduce the HW analyzer usage.
> >
> > The debugfs entries can be used to get information about underlying
> > hardware and can be shared with user space. Separate debugfs entries
> > has been created to cater to all the DES hooks provided by the controller.
> > The debugfs entries interacts with the RASDES registers in the
> > required sequence and provides the meaningful data to the user. This
> > eases the effort to understand and use the register information for debugging.
> >
> > This series creates a generic debugfs framework for DesignWare PCIe
> > controllers where other debug features apart from RASDES can also be
> > added as and when required.
> 
> FWIW, for the series:
> Tested-by: Niklas Cassel <cassel@xxxxxxxxxx>

Hey Niklas, sent out v7 with a few minor modifications. Would be great if you could test that :)