[PATCH 0/2] Subject: [PATCH 0/2] PCI: cadence: Add LTSSM debugfs

From: Hans Zhang

Date: Sun Mar 15 2026 - 11:56:03 EST


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.

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 | 211 ++++++++++++++++++
.../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, 390 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