On Tue, 25 Jun 2024 15:08:10 +0530 Shradha Todi <shradha.t@xxxxxxxxxxx> 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. To consider this properly I think some documentation is needed. Maybe just ABI in Documentation/ABI/testing/debugfs-* or maybe a more freestanding document. > > v2: https://lore.kernel.org/lkml/20240319163315.GD3297@thinkpad/T/ > > 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 | 474 ++++++++++++++++++ > .../controller/dwc/pcie-designware-debugfs.h | 0 > .../pci/controller/dwc/pcie-designware-host.c | 2 + > drivers/pci/controller/dwc/pcie-designware.c | 20 + > drivers/pci/controller/dwc/pcie-designware.h | 18 + > 7 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 >
