Hi all,

This set adds basic support for using the Flit Logging capability
introduced in PCIe v6.0.

The work was started by Avadhut, and I took over after he left AMD.

Design Notes and Limitations:
* Only enabled for ports using a service driver.
 * Other device types can and do support this capability.
 * The interrupt is managed per-device. So each driver would need to add
   their own support. In other words, there isn't a centralized handling
   flow as currently described in the spec.
 * A future Flit Logging capability revision will use a centralized flow
   similar to AER. But that is not covered in this set.
* Included ratelimiting for messages.
 * Initial thought was to do "interrupt storm handling" similar to MCA.
 * It's not clear to me if that's necessary, so I went with a similar
   solution to AER.
* Flit logging CPER decoding is not covered.
 * There is a proposed change to include DPC and Flit data in the PCIe
   CPER section format. This would be used in FW-First handling.
 * IIRC, the format still isn't settled, so I left it out of this set.

AI Assistance Notes:
* Patch 2 was originally written by Avadhut, and I made a few fixups.
* The code in patch 3 was originally written by me.
* Patches 1, 4, and 5 were written with AI assistance.
* AI assistance was used for squashing, splitting, refactoring, and
  reviewing the patches.

Thanks,
Yazen

Avadhut Naik (1):
  PCI/FLIT: Add support for Flit Logging Extended Capability

Yazen Ghannam (4):
  PCI/portdrv: Group PCI Exp Cap services into a single mask
  PCI/FLIT: Negotiate _OSC control for Flit Error Logging
  PCI/FLIT: Add trace event for flit errors
  PCI/FLIT: Ratelimit flit error logging

 drivers/acpi/pci_root.c       |   6 +
 drivers/pci/pci-sysfs.c       |   3 +
 drivers/pci/pci.h             |   7 +
 drivers/pci/pcie/Kconfig      |  11 ++
 drivers/pci/pcie/Makefile     |   1 +
 drivers/pci/pcie/flit.c       | 283 ++++++++++++++++++++++++++++++++++
 drivers/pci/pcie/portdrv.c    |  23 ++-
 drivers/pci/pcie/portdrv.h    |  10 +-
 drivers/pci/probe.c           |   2 +
 include/linux/acpi.h          |   1 +
 include/linux/pci.h           |   7 +
 include/ras/ras_event.h       |  48 ++++++
 include/uapi/linux/pci_regs.h |  14 +-
 13 files changed, 409 insertions(+), 7 deletions(-)
 create mode 100644 drivers/pci/pcie/flit.c


base-commit: 5d9f1dd3b3e7bd64ac7ddedf28fcb7db81053819
-- 
2.53.0