Hi,

This series adds debugfs support to the Cadence PCIe controller driver,
allowing users to read the current LTSSM state of the link for debugging
purposes.

Patch 1 introduces a new flag 'is_hpa' in the cdns_pcie structure to
distinguish HPA (High Performance Architecture IP) platforms, which
have a different register layout for LTSSM status.

Patch 2 implements the debugfs file "ltssm_status" under a per-device
directory. It reads the LTSSM state from the appropriate hardware register
based on the 'is_hpa' flag and displays both a descriptive string and the
raw value.

---
Changes for v2:
- s/DW_PCIE_LTSSM_NAME/CDNS_PCIE_LTSSM_NAME/
- S/January 2026/March 2026/
- EXPORT_SYMBOL_GPL(cdns_pcie_debugfs_init); // Resolve the following error issues.
  >> ERROR: modpost: "cdns_pcie_debugfs_init" [drivers/pci/controller/cadence/pcie-cadence-host-mod.ko] undefined!
  >> ERROR: modpost: "cdns_pcie_debugfs_init" [drivers/pci/controller/cadence/pcie-cadence-ep-mod.ko] undefined!

v1:
https://patchwork.kernel.org/project/linux-pci/cover/20260315155514.127255-1-18255117159@163.com/
---

Hans Zhang (2):
  PCI: cadence: Add HPA architecture flag
  PCI: cadence: Add debugfs property to provide LTSSM status of the PCIe
    link

 Documentation/ABI/testing/debugfs-cdns-pcie   |   5 +
 drivers/pci/controller/cadence/Kconfig        |   9 +
 drivers/pci/controller/cadence/Makefile       |   1 +
 drivers/pci/controller/cadence/pci-sky1.c     |   1 +
 .../controller/cadence/pcie-cadence-debugfs.c | 214 ++++++++++++++++++
 .../pci/controller/cadence/pcie-cadence-ep.c  |   2 +
 .../cadence/pcie-cadence-host-hpa.c           |   8 +-
 .../controller/cadence/pcie-cadence-host.c    |   8 +-
 drivers/pci/controller/cadence/pcie-cadence.h | 147 ++++++++++++
 9 files changed, 393 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/ABI/testing/debugfs-cdns-pcie
 create mode 100644 drivers/pci/controller/cadence/pcie-cadence-debugfs.c


base-commit: 1c9982b4961334c1edb0745a04cabd34bc2de675
-- 
2.34.1