[PATCH v2 0/3] Add support for RAS DES feature in PCIe DW controller

[Shradha Todi]

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.

v1 version was posted long back and for some reasons I couldn't work on
it. I apologize for the long break. I'm restarting this activity and
have taken care of all previous review comments shared.
v1: https://lore.kernel.org/all/20210518174618.42089-1-shradha.t@xxxxxxxxxxx/T/

Shradha Todi (3):
  PCI: dwc: Add support for vendor specific capability search
  PCI: debugfs: Add support for RASDES framework in DWC
  PCI: dwc: Create debugfs files in DWC driver

 drivers/pci/controller/dwc/Kconfig            |   8 +
 drivers/pci/controller/dwc/Makefile           |   1 +
 .../controller/dwc/pcie-designware-debugfs.c  | 476 ++++++++++++++++++
 .../controller/dwc/pcie-designware-debugfs.h  |   0
 drivers/pci/controller/dwc/pcie-designware.c  |  20 +
 drivers/pci/controller/dwc/pcie-designware.h  |  18 +
 6 files changed, 523 insertions(+)
 create mode 100644 drivers/pci/controller/dwc/pcie-designware-debugfs.c
 create mode 100644 drivers/pci/controller/dwc/pcie-designware-debugfs.h

-- 
2.17.1