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* [PATCH v6 0/3] PCI: cadence: Add LTSSM debugfs
@ 2026-05-19 12:36 Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 1/3] PCI: cadence: Add HPA architecture flag Hans Zhang
                   ` (2 more replies)
  0 siblings, 3 replies; 13+ messages in thread
From: Hans Zhang @ 2026-05-19 12:36 UTC (permalink / raw)
  To: bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, a-garg7, s-vadapalli, linux-pci, linux-kernel,
	Hans Zhang

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 from LGA
(Legacy Architecture) IP platforms, as they have different register
layouts for LTSSM status.

Patch 2 implements the debugfs file "ltssm_status" for HPA IP 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.

Patch 3 adds LTSSM debugfs support for LGA IP, utilizing a new callback
'get_lga_ltssm' in cdns_pcie_ops to read the LTSSM state from the LGA
register. The debugfs interface now supports both IP types seamlessly.

=====================
Test:
root@orangepi6plus:~# ls -l /sys/kernel/debug/cdns_pcie_a0*
/sys/kernel/debug/cdns_pcie_a010000.pcie:
total 0
-r--r--r-- 1 root root 0 Jan  1  1970 ltssm_status

/sys/kernel/debug/cdns_pcie_a0c0000.pcie:
total 0
-r--r--r-- 1 root root 0 Jan  1  1970 ltssm_status

/sys/kernel/debug/cdns_pcie_a0e0000.pcie:
total 0
-r--r--r-- 1 root root 0 Jan  1  1970 ltssm_status
root@orangepi6plus:~# 
root@orangepi6plus:~# 
root@orangepi6plus:~# cat /sys/kernel/debug/cdns_pcie_a0*/ltss*
L0_STATE (0x29)
L0_STATE (0x29)
L0_STATE (0x29)
root@orangepi6plus:~# 
root@orangepi6plus:~# uname -a
Linux orangepi6plus 7.1.0-rc3-00007-ge3963f3f4e31 #62 SMP PREEMPT Tue May 19 20:28:24 CST 2026 aarch64 aarch64 aarch64 GNUx
=====================

---
Changes for v6:
- The LTSSM status of the LGA IP no longer contains the "LTSSM_" character. (Aksh)

Changes for v5:
- Split LGA and HPA LTSSM debugfs support into separate patches as they
  have different register definitions and access methods. (Aksh, Manikandan)
- Add cdns_pcie_hpa_host_disable() to properly clean up debugfs on
  removal (Mani)
- Remove redundant copyright email address (Mani)

Changes for v4:
- Remove the copyright email address of the author of pcie-cadence-debugfs.c (Mani)
- Add cdns_pcie_hpa_host_disable() (Mani)
- Use DEFINE_SHOW_ATTRIBUTE() (Mani & Sashiko)

Changes for v3:
- Export cdns_pcie_debugfs_deinit (Mani)
- pcie-cadence-ep.c pcie-cadence-host.c pci-sky1.c call cdns_pcie_debugfs_deinit

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!

v5:
https://patchwork.kernel.org/project/linux-pci/patch/20260515145747.129635-1-18255117159@163.com/
v4:
https://patchwork.kernel.org/project/linux-pci/patch/20260508034101.1910036-1-18255117159@163.com/
v3:
https://patchwork.kernel.org/project/linux-pci/patch/20260406103237.1203127-1-18255117159@163.com/
v2:
https://patchwork.kernel.org/project/linux-pci/patch/20260321033035.3008585-3-18255117159@163.com/
v1:
https://patchwork.kernel.org/project/linux-pci/cover/20260315155514.127255-1-18255117159@163.com/

Hans Zhang (3):
  PCI: cadence: Add HPA architecture flag
  PCI: cadence: Add HPA IP debugfs for LTSSM status
  PCI: cadence: Add LGA IP debugfs for LTSSM status

 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     |   5 +
 .../controller/cadence/pcie-cadence-debugfs.c | 263 ++++++++++++++++++
 .../pci/controller/cadence/pcie-cadence-ep.c  |   3 +
 .../cadence/pcie-cadence-host-hpa.c           |  19 +-
 .../controller/cadence/pcie-cadence-host.c    |   9 +-
 drivers/pci/controller/cadence/pcie-cadence.h | 198 +++++++++++++
 9 files changed, 510 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: 50897c955902c93ae71c38698abb910525ebdc89
-- 
2.43.0


^ permalink raw reply	[flat|nested] 13+ messages in thread

* [PATCH v6 1/3] PCI: cadence: Add HPA architecture flag
  2026-05-19 12:36 [PATCH v6 0/3] PCI: cadence: Add LTSSM debugfs Hans Zhang
@ 2026-05-19 12:36 ` Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 3/3] PCI: cadence: Add LGA " Hans Zhang
  2 siblings, 0 replies; 13+ messages in thread
From: Hans Zhang @ 2026-05-19 12:36 UTC (permalink / raw)
  To: bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, a-garg7, s-vadapalli, linux-pci, linux-kernel,
	Hans Zhang

Add a boolean flag 'is_hpa' to the cdns_pcie structure to indicate
that the controller is part of a Heterogeneous Processor Architecture
(HPA) system. This flag will be used by subsequent patches to handle
HPA-specific register layouts and behaviors.

Signed-off-by: Hans Zhang <18255117159@163.com>
---
 drivers/pci/controller/cadence/pci-sky1.c     | 1 +
 drivers/pci/controller/cadence/pcie-cadence.h | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/drivers/pci/controller/cadence/pci-sky1.c b/drivers/pci/controller/cadence/pci-sky1.c
index cd55c64e58a9..e1f4a98e2ab6 100644
--- a/drivers/pci/controller/cadence/pci-sky1.c
+++ b/drivers/pci/controller/cadence/pci-sky1.c
@@ -174,6 +174,7 @@ static int sky1_pcie_probe(struct platform_device *pdev)
 	cdns_pcie->reg_base = pcie->reg_base;
 	cdns_pcie->msg_res = pcie->msg_res;
 	cdns_pcie->is_rc = true;
+	cdns_pcie->is_hpa = true;
 
 	reg_off = devm_kzalloc(dev, sizeof(*reg_off), GFP_KERNEL);
 	if (!reg_off) {
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 574e9cf4d003..9a464cbaf073 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -80,6 +80,7 @@ struct cdns_plat_pcie_of_data {
  * @msg_res: Region for send message to map PCI accesses
  * @dev: PCIe controller
  * @is_rc: tell whether the PCIe controller mode is Root Complex or Endpoint.
+ * @is_hpa: indicates if the architecture is HPA
  * @phy_count: number of supported PHY devices
  * @phy: list of pointers to specific PHY control blocks
  * @link: list of pointers to corresponding device link representations
@@ -93,6 +94,7 @@ struct cdns_pcie {
 	struct resource                      *msg_res;
 	struct device		             *dev;
 	bool			             is_rc;
+	bool				     is_hpa;
 	int			             phy_count;
 	struct phy		             **phy;
 	struct device_link	             **link;
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status
  2026-05-19 12:36 [PATCH v6 0/3] PCI: cadence: Add LTSSM debugfs Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 1/3] PCI: cadence: Add HPA architecture flag Hans Zhang
@ 2026-05-19 12:36 ` Hans Zhang
  2026-05-19 13:20   ` sashiko-bot
  2026-05-20  7:26   ` Aksh Garg
  2026-05-19 12:36 ` [PATCH v6 3/3] PCI: cadence: Add LGA " Hans Zhang
  2 siblings, 2 replies; 13+ messages in thread
From: Hans Zhang @ 2026-05-19 12:36 UTC (permalink / raw)
  To: bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, a-garg7, s-vadapalli, linux-pci, linux-kernel,
	Hans Zhang

Add debugfs support for HPA-based Cadence PCIe controllers. A new file
'ltssm_status' is created under debugfs, allowing users to read the
current LTSSM state as a string and raw value.

Signed-off-by: Hans Zhang <18255117159@163.com>
---
 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     |   4 +
 .../controller/cadence/pcie-cadence-debugfs.c | 208 ++++++++++++++++++
 .../cadence/pcie-cadence-host-hpa.c           |  19 +-
 drivers/pci/controller/cadence/pcie-cadence.h | 153 +++++++++++++
 7 files changed, 398 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/ABI/testing/debugfs-cdns-pcie
 create mode 100644 drivers/pci/controller/cadence/pcie-cadence-debugfs.c

diff --git a/Documentation/ABI/testing/debugfs-cdns-pcie b/Documentation/ABI/testing/debugfs-cdns-pcie
new file mode 100644
index 000000000000..c1104e28e4ee
--- /dev/null
+++ b/Documentation/ABI/testing/debugfs-cdns-pcie
@@ -0,0 +1,5 @@
+What:		/sys/kernel/debug/cdns_pcie_<dev>/ltssm_status
+Date:		March 2026
+Contact:	Hans Zhang <18255117159@163.com>
+Description:	(RO) Read will return the current PCIe LTSSM state in both
+		string and raw value.
\ No newline at end of file
diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/controller/cadence/Kconfig
index 9e651d545973..cb010bc97aad 100644
--- a/drivers/pci/controller/cadence/Kconfig
+++ b/drivers/pci/controller/cadence/Kconfig
@@ -6,6 +6,15 @@ menu "Cadence-based PCIe controllers"
 config PCIE_CADENCE
 	tristate
 
+config PCIE_CADENCE_DEBUGFS
+	tristate "Cadence PCIe debugfs entries"
+	depends on DEBUG_FS
+	depends on PCIE_CADENCE_HOST || PCIE_CADENCE_EP
+	help
+	  Say Y here to enable debugfs entries for the PCIe controller. These
+	  entries provide various debug features related to the controller and
+	  the LTSSM status of link can be displayed.
+
 config PCIE_CADENCE_HOST
 	tristate
 	depends on OF
diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/controller/cadence/Makefile
index b8ec1cecfaa8..2cdc4617e0c2 100644
--- a/drivers/pci/controller/cadence/Makefile
+++ b/drivers/pci/controller/cadence/Makefile
@@ -4,6 +4,7 @@ pcie-cadence-host-mod-y := pcie-cadence-host-common.o pcie-cadence-host.o pcie-c
 pcie-cadence-ep-mod-y := pcie-cadence-ep.o
 
 obj-$(CONFIG_PCIE_CADENCE) = pcie-cadence-mod.o
+obj-$(CONFIG_PCIE_CADENCE_DEBUGFS) += pcie-cadence-debugfs.o
 obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host-mod.o
 obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep-mod.o
 obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
diff --git a/drivers/pci/controller/cadence/pci-sky1.c b/drivers/pci/controller/cadence/pci-sky1.c
index e1f4a98e2ab6..b8632f1d3156 100644
--- a/drivers/pci/controller/cadence/pci-sky1.c
+++ b/drivers/pci/controller/cadence/pci-sky1.c
@@ -221,6 +221,10 @@ MODULE_DEVICE_TABLE(of, of_sky1_pcie_match);
 static void sky1_pcie_remove(struct platform_device *pdev)
 {
 	struct sky1_pcie *pcie = platform_get_drvdata(pdev);
+	struct cdns_pcie_rc *rc;
+
+	rc = container_of(pcie->cdns_pcie, struct cdns_pcie_rc, pcie);
+	cdns_pcie_hpa_host_disable(rc);
 
 	pci_ecam_free(pcie->cfg);
 }
diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
new file mode 100644
index 000000000000..97c5deef2b1a
--- /dev/null
+++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence PCIe controller debugfs driver
+ *
+ * Copyright (C) 2026 Hans Zhang <18255117159@163.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include "pcie-cadence.h"
+
+#define CDNS_DEBUGFS_BUF_MAX		128
+
+static const char *cdns_pcie_hpa_ltssm_status_string(enum cdns_pcie_hpa_ltssm ltssm)
+{
+	const char *str;
+
+	switch (ltssm) {
+#define CDNS_PCIE_HPA_LTSSM_NAME(n) case n: str = #n; break
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_QUIET);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_QUIET_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RCVR_DETECTED_ST);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RCVR_DETECTED_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_ACC_RC);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_RC);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_RC_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_RC);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LW_ACC_EP);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_EP);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_EP_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_EP);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_EP_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_IDLE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_CONFIG_IDLE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0_STATE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_LOCK);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_LOCK_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_CFG);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_CFG_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_IDLE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_IDLE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_6);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_7);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_HOT_RESET);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_HOT_RESET_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_HOT_RESET_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_HOT_RESET_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L0S_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_WAIT_FOR_LINK_TX);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_FTS_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_FTS_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_FTS_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_ST);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_6);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_7);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_8);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ENTRY_FROM_RECOVERY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_EXIT_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_EXIT);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ACTIVE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_IDLE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L1_EXIT);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_L2_IDLE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_3);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_4);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_5);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_FROM_RECOVERY);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ACTIVE);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE0);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE2_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE2_2);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE3_1);
+	CDNS_PCIE_HPA_LTSSM_NAME(CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE3_2);
+	default:
+		str = "CDNS_PCIE_HPA_LTSSM_UNKNOWN";
+		break;
+	}
+
+	return str + strlen("CDNS_PCIE_HPA_LTSSM_");
+}
+
+static int ltssm_status_show(struct seq_file *s, void *v)
+{
+	struct cdns_pcie *pci = s->private;
+	enum cdns_pcie_hpa_ltssm hpa_ltssm;
+	const char *str_ltssm;
+	u32 val;
+
+	if (pci->is_hpa) {
+		val = cdns_pcie_hpa_readl(pci, REG_BANK_IP_REG,
+					  CDNS_PCIE_HPA_PHY_DBG_STS_REG0);
+		hpa_ltssm = FIELD_GET(CDNS_PCIE_HPA_LTSSM_STATUS_MASK, val);
+		str_ltssm = cdns_pcie_hpa_ltssm_status_string(hpa_ltssm);
+	} else {
+		/* TODO: LGA IP*/
+		return 0;
+	}
+
+	seq_printf(s, "%s (0x%02x)\n", str_ltssm, hpa_ltssm);
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(ltssm_status);
+
+static void cdns_pcie_ltssm_debugfs_init(struct cdns_pcie *pci, struct dentry *dir)
+{
+	debugfs_create_file("ltssm_status", 0444, dir, pci,
+			    &ltssm_status_fops);
+}
+
+void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
+{
+	if (!pci->debug_dir)
+		return;
+
+	debugfs_remove_recursive(pci->debug_dir);
+}
+EXPORT_SYMBOL_GPL(cdns_pcie_debugfs_deinit);
+
+void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
+{
+	char dirname[CDNS_DEBUGFS_BUF_MAX];
+	struct device *dev = pci->dev;
+
+	/* Create main directory for each platform driver. */
+	snprintf(dirname, CDNS_DEBUGFS_BUF_MAX, "cdns_pcie_%s", dev_name(dev));
+	pci->debug_dir = debugfs_create_dir(dirname, NULL);
+
+	cdns_pcie_ltssm_debugfs_init(pci, pci->debug_dir);
+}
+EXPORT_SYMBOL_GPL(cdns_pcie_debugfs_init);
diff --git a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c b/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
index 0f540bed58e8..abc1d0e58b98 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
@@ -309,6 +309,17 @@ int cdns_pcie_hpa_host_link_setup(struct cdns_pcie_rc *rc)
 }
 EXPORT_SYMBOL_GPL(cdns_pcie_hpa_host_link_setup);
 
+void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc)
+{
+	struct pci_host_bridge *bridge;
+
+	cdns_pcie_debugfs_deinit(&rc->pcie);
+	bridge = pci_host_bridge_from_priv(rc);
+	pci_stop_root_bus(bridge->bus);
+	pci_remove_root_bus(bridge->bus);
+}
+EXPORT_SYMBOL_GPL(cdns_pcie_hpa_host_disable);
+
 int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc *rc)
 {
 	struct device *dev = rc->pcie.dev;
@@ -360,7 +371,13 @@ int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc *rc)
 	if (!bridge->ops)
 		bridge->ops = &cdns_pcie_hpa_host_ops;
 
-	return pci_host_probe(bridge);
+	ret = pci_host_probe(bridge);
+	if (ret)
+		return ret;
+
+	cdns_pcie_debugfs_init(pcie);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(cdns_pcie_hpa_host_setup);
 
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 9a464cbaf073..2320319af83b 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -14,6 +14,8 @@
 #include "pcie-cadence-lga-regs.h"
 #include "pcie-cadence-hpa-regs.h"
 
+#define CDNS_PCIE_HPA_LTSSM_STATUS_MASK	GENMASK(27, 20)
+
 enum cdns_pcie_rp_bar {
 	RP_BAR_UNDEFINED = -1,
 	RP_BAR0,
@@ -42,6 +44,138 @@ enum cdns_pcie_reg_bank {
 	REG_BANKS_MAX,
 };
 
+enum cdns_pcie_hpa_ltssm {
+	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET		= 0,
+	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET_ENTRY		= 1,
+	CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE		= 2,
+	CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_1		= 3,
+	CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_2		= 4,
+	CDNS_PCIE_HPA_LTSSM_DETECT_ACTIVE_3		= 5,
+	CDNS_PCIE_HPA_LTSSM_RCVR_DETECTED_ST		= 6,
+	CDNS_PCIE_HPA_LTSSM_RCVR_DETECTED_1		= 7,
+	CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE		= 8,
+	CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_1		= 9,
+	CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_2		= 10,
+	CDNS_PCIE_HPA_LTSSM_POLLING_ACTIVE_3		= 11,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE		= 12,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_1	= 13,
+	CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG		= 14,
+	CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG_1		= 15,
+	CDNS_PCIE_HPA_LTSSM_POLLING_CONFIG_2		= 16,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC		= 17,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC_1	= 18,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_RC_2	= 19,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_ACC_RC		= 20,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_RC	= 21,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_RC_1	= 22,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_RC	= 23,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP		= 24,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP_1	= 25,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_START_EP_2	= 26,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LW_ACC_EP		= 27,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_EP	= 28,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_WAIT_EP_1	= 29,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_EP	= 30,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_LANENUM_ACC_EP_1	= 31,
+	CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_1		= 32,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE		= 33,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE_1		= 34,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_COMPLETE_2		= 35,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_IDLE			= 36,
+	CDNS_PCIE_HPA_LTSSM_CONFIG_IDLE_1		= 37,
+	CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_2		= 38,
+	CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_3		= 39,
+	CDNS_PCIE_HPA_LTSSM_DUMMY_STATE_4		= 40,
+	CDNS_PCIE_HPA_LTSSM_L0_STATE			= 41,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_LOCK		= 42,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_LOCK_1	= 43,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_CFG		= 44,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_RCVR_CFG_1		= 45,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_IDLE		= 46,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_IDLE_1		= 47,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK		= 48,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_1		= 49,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_2		= 50,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_3		= 51,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_4		= 52,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_5		= 53,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_6		= 54,
+	CDNS_PCIE_HPA_LTSSM_DISABLE_LINK_7		= 55,
+	CDNS_PCIE_HPA_LTSSM_HOT_RESET			= 56,
+	CDNS_PCIE_HPA_LTSSM_HOT_RESET_1			= 57,
+	CDNS_PCIE_HPA_LTSSM_HOT_RESET_2			= 58,
+	CDNS_PCIE_HPA_LTSSM_HOT_RESET_3			= 59,
+	CDNS_PCIE_HPA_LTSSM_L0S_ENTRY			= 60,
+	CDNS_PCIE_HPA_LTSSM_L0S_1			= 61,
+	CDNS_PCIE_HPA_LTSSM_L0S_2			= 62,
+	CDNS_PCIE_HPA_LTSSM_L0S_3			= 63,
+	CDNS_PCIE_HPA_LTSSM_L0S_4			= 64,
+	CDNS_PCIE_HPA_LTSSM_L0S_5			= 65,
+	CDNS_PCIE_HPA_LTSSM_WAIT_FOR_LINK_TX		= 66,
+	CDNS_PCIE_HPA_LTSSM_TX_FTS_ENTRY		= 67,
+	CDNS_PCIE_HPA_LTSSM_TX_FTS_1			= 68,
+	CDNS_PCIE_HPA_LTSSM_TX_FTS_2			= 69,
+	CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_ST		= 70,
+	CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_1		= 71,
+	CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_2		= 72,
+	CDNS_PCIE_HPA_LTSSM_TX_ELEC_IDLE_3		= 73,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED		= 74,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_1		= 75,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_2		= 76,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_SPEED_3		= 77,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23	= 78,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_1	= 79,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_2	= 80,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_3	= 81,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_4	= 82,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_5	= 83,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_6	= 84,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_7	= 85,
+	CDNS_PCIE_HPA_LTSSM_POLLING_COMPLIANCE_GEN23_8	= 86,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ENTRY	= 87,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ENTRY_FROM_RECOVERY = 88,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_EXIT_1	= 89,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_EXIT		= 90,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_1	= 91,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_2	= 92,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_3	= 93,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_4	= 94,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_GEN2_5	= 95,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_SLAVE_ACTIVE	= 96,
+	CDNS_PCIE_HPA_LTSSM_L1_ENTRY			= 97,
+	CDNS_PCIE_HPA_LTSSM_L1_1			= 98,
+	CDNS_PCIE_HPA_LTSSM_L1_2			= 99,
+	CDNS_PCIE_HPA_LTSSM_L1_3			= 100,
+	CDNS_PCIE_HPA_LTSSM_L1_4			= 101,
+	CDNS_PCIE_HPA_LTSSM_L1_IDLE			= 102,
+	CDNS_PCIE_HPA_LTSSM_L1_EXIT			= 103,
+	CDNS_PCIE_HPA_LTSSM_L2_ENTRY			= 104,
+	CDNS_PCIE_HPA_LTSSM_L2_1			= 105,
+	CDNS_PCIE_HPA_LTSSM_L2_2			= 106,
+	CDNS_PCIE_HPA_LTSSM_L2_3			= 107,
+	CDNS_PCIE_HPA_LTSSM_L2_4			= 108,
+	CDNS_PCIE_HPA_LTSSM_L2_5			= 109,
+	CDNS_PCIE_HPA_LTSSM_L2_IDLE			= 110,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY	= 111,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_1	= 112,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_2	= 113,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_3	= 114,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_4	= 115,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_5	= 116,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ENTRY_FROM_RECOVERY = 117,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_ACTIVE	= 118,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT	= 119,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT_1	= 120,
+	CDNS_PCIE_HPA_LTSSM_LOOPBACK_MASTER_EXIT_2	= 121,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE0 = 122,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE1 = 123,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE2_1 = 124,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE2_2 = 125,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE3_1 = 126,
+	CDNS_PCIE_HPA_LTSSM_RECOVERY_EQUALIZATION_PHASE3_2 = 127,
+	CDNS_PCIE_HPA_LTSSM_UNKNOWN			= 0xFFFFFFFF,
+};
+
 struct cdns_pcie_ops {
 	int     (*start_link)(struct cdns_pcie *pcie);
 	void    (*stop_link)(struct cdns_pcie *pcie);
@@ -87,6 +221,7 @@ struct cdns_plat_pcie_of_data {
  * @ops: Platform-specific ops to control various inputs from Cadence PCIe
  *       wrapper
  * @cdns_pcie_reg_offsets: Register bank offsets for different SoC
+ * @debug_dir: debugfs node
  */
 struct cdns_pcie {
 	void __iomem		             *reg_base;
@@ -100,6 +235,7 @@ struct cdns_pcie {
 	struct device_link	             **link;
 	const  struct cdns_pcie_ops          *ops;
 	const  struct cdns_plat_pcie_of_data *cdns_pcie_reg_offsets;
+	struct dentry			     *debug_dir;
 };
 
 /**
@@ -447,6 +583,7 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc);
 void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 			       int where);
 int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc *rc);
+void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc);
 #else
 static inline int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
 {
@@ -472,6 +609,10 @@ static inline void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
 {
 }
 
+static inline void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc)
+{
+}
+
 static inline void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 					     int where)
 {
@@ -535,4 +676,16 @@ bool cdns_pcie_hpa_link_up(struct cdns_pcie *pcie);
 
 extern const struct dev_pm_ops cdns_pcie_pm_ops;
 
+#ifdef CONFIG_PCIE_CADENCE_DEBUGFS
+void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci);
+void cdns_pcie_debugfs_init(struct cdns_pcie *pci);
+#else
+static inline void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
+{
+}
+static inline void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
+{
+}
+#endif
+
 #endif /* _PCIE_CADENCE_H */
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-19 12:36 [PATCH v6 0/3] PCI: cadence: Add LTSSM debugfs Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 1/3] PCI: cadence: Add HPA architecture flag Hans Zhang
  2026-05-19 12:36 ` [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status Hans Zhang
@ 2026-05-19 12:36 ` Hans Zhang
  2026-05-20  2:34   ` Manikandan Karunakaran Pillai
  2 siblings, 1 reply; 13+ messages in thread
From: Hans Zhang @ 2026-05-19 12:36 UTC (permalink / raw)
  To: bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, a-garg7, s-vadapalli, linux-pci, linux-kernel,
	Hans Zhang

Extend debugfs support to LGA-based Cadence PCIe controllers. The
'ltssm_status' file now works for both HPA and LGA IP by selecting the
appropriate register access based on the 'is_hpa' flag.

Signed-off-by: Hans Zhang <18255117159@163.com>
---
 .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
 .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
 .../controller/cadence/pcie-cadence-host.c    |  9 ++-
 drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
 4 files changed, 112 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
index 97c5deef2b1a..0a308f95e9f6 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
@@ -13,6 +13,58 @@
 
 #define CDNS_DEBUGFS_BUF_MAX		128
 
+static const char *cdns_pcie_lga_ltssm_status_string(enum cdns_pcie_lga_ltssm ltssm)
+{
+	const char *str;
+
+	switch (ltssm) {
+#define CDNS_PCIE_LGA_LTSSM_NAME(n) case n: str = #n; break
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DETECT_QUIET);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DETECT_ACTIVE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_ACTIVE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_COMPLIANCE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_CONFIGURATION);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_START);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_ACCEPT);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_ACCEPT);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_WAIT);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_COMPLETE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURATION_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRLOCK);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_SPEED);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRCFG);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L0);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_ENTRY);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_FTS);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_ENTRY);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_FTS);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L1_ENTRY);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L1_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L2_IDLE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L2_TRANSMITWAKE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DISABLED);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_MASTER);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_MASTER);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_MASTER);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_SLAVE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_SLAVE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_SLAVE);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_HOT_RESET);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_0);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_1);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_2);
+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_3);
+	default:
+		str = "CDNS_PCIE_LGA_LTSSM_UNKNOWN";
+		break;
+	}
+
+	return str + strlen("CDNS_PCIE_LGA_LTSSM_");
+}
+
 static const char *cdns_pcie_hpa_ltssm_status_string(enum cdns_pcie_hpa_ltssm ltssm)
 {
 	const char *str;
@@ -158,6 +210,7 @@ static const char *cdns_pcie_hpa_ltssm_status_string(enum cdns_pcie_hpa_ltssm lt
 static int ltssm_status_show(struct seq_file *s, void *v)
 {
 	struct cdns_pcie *pci = s->private;
+	enum cdns_pcie_lga_ltssm lga_ltssm;
 	enum cdns_pcie_hpa_ltssm hpa_ltssm;
 	const char *str_ltssm;
 	u32 val;
@@ -168,11 +221,13 @@ static int ltssm_status_show(struct seq_file *s, void *v)
 		hpa_ltssm = FIELD_GET(CDNS_PCIE_HPA_LTSSM_STATUS_MASK, val);
 		str_ltssm = cdns_pcie_hpa_ltssm_status_string(hpa_ltssm);
 	} else {
-		/* TODO: LGA IP*/
-		return 0;
+		val = cdns_pcie_readl(pci, CDNS_PCIE_LM_BASE);
+		lga_ltssm = FIELD_GET(CDNS_PCIE_LGA_LTSSM_STATUS_MASK, val);
+		str_ltssm = cdns_pcie_lga_ltssm_status_string(lga_ltssm);
 	}
 
-	seq_printf(s, "%s (0x%02x)\n", str_ltssm, hpa_ltssm);
+	seq_printf(s, "%s (0x%02x)\n", str_ltssm,
+		   pci->is_hpa ? hpa_ltssm : lga_ltssm);
 
 	return 0;
 }
diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index c0e1194a936b..370b19f4d38f 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -655,6 +655,7 @@ void cdns_pcie_ep_disable(struct cdns_pcie_ep *ep)
 	struct device *dev = ep->pcie.dev;
 	struct pci_epc *epc = to_pci_epc(dev);
 
+	cdns_pcie_debugfs_deinit(&ep->pcie);
 	pci_epc_deinit_notify(epc);
 	pci_epc_mem_free_addr(epc, ep->irq_phys_addr, ep->irq_cpu_addr,
 			      SZ_128K);
@@ -761,6 +762,8 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
 
 	pci_epc_init_notify(epc);
 
+	cdns_pcie_debugfs_init(pcie);
+
 	return 0;
 
  free_epc_mem:
diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 0bc9e6e90e0e..8105bb625eb7 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -364,6 +364,7 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
 {
 	struct pci_host_bridge *bridge;
 
+	cdns_pcie_debugfs_deinit(&rc->pcie);
 	bridge = pci_host_bridge_from_priv(rc);
 	pci_stop_root_bus(bridge->bus);
 	pci_remove_root_bus(bridge->bus);
@@ -423,7 +424,13 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 	if (!bridge->ops)
 		bridge->ops = &cdns_pcie_host_ops;
 
-	return pci_host_probe(bridge);
+	ret = pci_host_probe(bridge);
+	if (ret)
+		return ret;
+
+	cdns_pcie_debugfs_init(pcie);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(cdns_pcie_host_setup);
 
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 2320319af83b..8bc6564c65b9 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -14,6 +14,7 @@
 #include "pcie-cadence-lga-regs.h"
 #include "pcie-cadence-hpa-regs.h"
 
+#define CDNS_PCIE_LGA_LTSSM_STATUS_MASK	GENMASK(29, 24)
 #define CDNS_PCIE_HPA_LTSSM_STATUS_MASK	GENMASK(27, 20)
 
 enum cdns_pcie_rp_bar {
@@ -44,6 +45,48 @@ enum cdns_pcie_reg_bank {
 	REG_BANKS_MAX,
 };
 
+enum cdns_pcie_lga_ltssm {
+	CDNS_PCIE_LGA_LTSSM_DETECT_QUIET			= 0x00,
+	CDNS_PCIE_LGA_LTSSM_DETECT_ACTIVE			= 0x01,
+	CDNS_PCIE_LGA_LTSSM_POLLING_ACTIVE			= 0x02,
+	CDNS_PCIE_LGA_LTSSM_POLLING_COMPLIANCE			= 0x03,
+	CDNS_PCIE_LGA_LTSSM_POLLING_CONFIGURATION		= 0x04,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_START	= 0x05,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_ACCEPT	= 0x06,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_ACCEPT	= 0x07,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_WAIT		= 0x08,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_COMPLETE		= 0x09,
+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_IDLE			= 0x0A,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRLOCK			= 0x0B,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_SPEED			= 0x0C,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRCFG			= 0x0D,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_IDLE			= 0x0E,
+	CDNS_PCIE_LGA_LTSSM_L0					= 0x10,
+	CDNS_PCIE_LGA_LTSSM_RX_L0S_ENTRY			= 0x11,
+	CDNS_PCIE_LGA_LTSSM_RX_L0S_IDLE				= 0x12,
+	CDNS_PCIE_LGA_LTSSM_RX_L0S_FTS				= 0x13,
+	CDNS_PCIE_LGA_LTSSM_TX_L0S_ENTRY			= 0x14,
+	CDNS_PCIE_LGA_LTSSM_TX_L0S_IDLE				= 0x15,
+	CDNS_PCIE_LGA_LTSSM_TX_L0S_FTS				= 0x16,
+	CDNS_PCIE_LGA_LTSSM_L1_ENTRY				= 0x17,
+	CDNS_PCIE_LGA_LTSSM_L1_IDLE				= 0x18,
+	CDNS_PCIE_LGA_LTSSM_L2_IDLE				= 0x19,
+	CDNS_PCIE_LGA_LTSSM_L2_TRANSMITWAKE			= 0x1A,
+	CDNS_PCIE_LGA_LTSSM_DISABLED				= 0x20,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_MASTER		= 0x21,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_MASTER		= 0x22,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_MASTER		= 0x23,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_SLAVE		= 0x24,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_SLAVE		= 0x25,
+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_SLAVE			= 0x26,
+	CDNS_PCIE_LGA_LTSSM_HOT_RESET				= 0x27,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_0	= 0x28,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_1	= 0x29,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_2	= 0x2A,
+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_3	= 0x2B,
+	CDNS_PCIE_LGA_LTSSM_UNKNOWN				= 0xFFFFFFFF,
+};
+
 enum cdns_pcie_hpa_ltssm {
 	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET		= 0,
 	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET_ENTRY		= 1,
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status
  2026-05-19 12:36 ` [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status Hans Zhang
@ 2026-05-19 13:20   ` sashiko-bot
  2026-05-20  7:26   ` Aksh Garg
  1 sibling, 0 replies; 13+ messages in thread
From: sashiko-bot @ 2026-05-19 13:20 UTC (permalink / raw)
  To: Hans Zhang; +Cc: linux-pci

Thank you for your contribution! Sashiko AI review found 4 potential issue(s) to consider:
- [High] Unprotected hardware register access in the debugfs read callback can cause a kernel panic if the device is runtime suspended.
- [High] Race condition during root bus teardown due to missing `pci_lock_rescan_remove()`.
- [Medium] Debugfs feature silently fails to initialize when compiled as a module due to incorrect Kconfig and preprocessor macro interaction.
- [Medium] The patch implicitly introduces critical behavioral changes (root bus teardown) not mentioned in the commit message.
--

commit 32300cb8f3d354c5d2edc089c48c2f9d49fdb425
Author: Hans Zhang <18255117159@163.com>

PCI: cadence: Add HPA IP debugfs for LTSSM status

This commit adds debugfs support for HPA-based Cadence PCIe controllers to
allow users to read the current LTSSM state. It also introduces root bus
teardown logic during device removal.

> Add debugfs support for HPA-based Cadence PCIe controllers. A new file
> 'ltssm_status' is created under debugfs, allowing users to read the
> current LTSSM state as a string and raw value.

This isn't a bug, but the patch appears to introduce behavioral changes for
root bus teardown (adding pci_stop_root_bus() and pci_remove_root_bus() via
cdns_pcie_hpa_host_disable()) that aren't mentioned in the commit message.

Should this bus teardown logic be split into a separate patch, or documented
in the commit message?

> diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/controller/cadence/Kconfig
> index 9e651d5459735..cb010bc97aad3 100644
> --- a/drivers/pci/controller/cadence/Kconfig
> +++ b/drivers/pci/controller/cadence/Kconfig
> @@ -6,6 +6,15 @@ menu "Cadence-based PCIe controllers"
>  config PCIE_CADENCE
>  	tristate
>  
> +config PCIE_CADENCE_DEBUGFS
> +	tristate "Cadence PCIe debugfs entries"

Could this cause silent failures if configured as a module?

If a user configures this as a module (=m), Kbuild will define
CONFIG_PCIE_CADENCE_DEBUGFS_MODULE instead of CONFIG_PCIE_CADENCE_DEBUGFS.

Because pcie-cadence.h guards the function declarations with
#ifdef CONFIG_PCIE_CADENCE_DEBUGFS, the core drivers will compile against
the empty static inline dummy functions instead.

Additionally, if we fix the macro to use IS_ENABLED(), would it cause linker
errors if the core driver is built-in (=y) but the debugfs is built as a
module (=m)?

Should this configuration option be changed to a bool?

[ ... ]

> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
> new file mode 100644
> index 0000000000000..97c5deef2b1ab
> --- /dev/null
> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
[ ... ]
> +static int ltssm_status_show(struct seq_file *s, void *v)
> +{
> +	struct cdns_pcie *pci = s->private;
> +	enum cdns_pcie_hpa_ltssm hpa_ltssm;
> +	const char *str_ltssm;
> +	u32 val;
> +
> +	if (pci->is_hpa) {
> +		val = cdns_pcie_hpa_readl(pci, REG_BANK_IP_REG,
> +					  CDNS_PCIE_HPA_PHY_DBG_STS_REG0);

Could accessing this register cause a kernel panic if the device is
runtime suspended?

Cadence PCIe platform drivers rely on runtime power management and will gate
clocks and power domains when idle.

If a user reads this debugfs file while the controller is runtime suspended,
will reading the memory-mapped register of a powered-off IP block trigger
a synchronous external abort?

Should this hardware access be wrapped with pm_runtime_get_sync(pci->dev)
and pm_runtime_put(pci->dev)?

[ ... ]

> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c b/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
> index 0f540bed58e88..abc1d0e58b981 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-host-hpa.c
[ ... ]
> +void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc)
> +{
> +	struct pci_host_bridge *bridge;
> +
> +	cdns_pcie_debugfs_deinit(&rc->pcie);
> +	bridge = pci_host_bridge_from_priv(rc);
> +	pci_stop_root_bus(bridge->bus);
> +	pci_remove_root_bus(bridge->bus);
> +}

Could this lead to a race condition during root bus teardown?

Calling pci_stop_root_bus() and pci_remove_root_bus() without holding the
PCI rescan lock allows race conditions with concurrent PCI rescan or hotplug
operations triggered via sysfs.

While this pattern might have been copied from a pre-existing function like
cdns_pcie_host_disable(), does it need to be fixed here to prevent
use-after-free or system crashes?

Should these operations be protected by acquiring the lock using
pci_lock_rescan_remove() and pci_unlock_rescan_remove()?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260519123609.1595280-1-18255117159@163.com?part=2

^ permalink raw reply	[flat|nested] 13+ messages in thread

* RE: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-19 12:36 ` [PATCH v6 3/3] PCI: cadence: Add LGA " Hans Zhang
@ 2026-05-20  2:34   ` Manikandan Karunakaran Pillai
  2026-05-20  2:59     ` Hans Zhang
  0 siblings, 1 reply; 13+ messages in thread
From: Manikandan Karunakaran Pillai @ 2026-05-20  2:34 UTC (permalink / raw)
  To: Hans Zhang, bhelgaas@google.com, lpieralisi@kernel.org,
	kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, a-garg7@ti.com, s-vadapalli@ti.com,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org

>EXTERNAL MAIL
>
>
>Extend debugfs support to LGA-based Cadence PCIe controllers. The
>'ltssm_status' file now works for both HPA and LGA IP by selecting the
>appropriate register access based on the 'is_hpa' flag.
>
>Signed-off-by: Hans Zhang <18255117159@163.com>
>---
> .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
> 4 files changed, 112 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>index 97c5deef2b1a..0a308f95e9f6 100644
>--- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>+++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>@@ -13,6 +13,58 @@
>
> #define CDNS_DEBUGFS_BUF_MAX		128

Where is CDNS_DEBUGFS_BUF_MAX used for ?

>
>+static const char *cdns_pcie_lga_ltssm_status_string(enum
>cdns_pcie_lga_ltssm ltssm)
>+{
>+	const char *str;
>+
>+	switch (ltssm) {
>+#define CDNS_PCIE_LGA_LTSSM_NAME(n) case n: str = #n; break
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DETECT_QUI
>ET);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DETECT_ACTI
>VE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_AC
>TIVE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_CO
>MPLIANCE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_POLLING_CO
>NFIGURATION);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_LINKWIDTH_START);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_LINKWIDTH_ACCEPT);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_LANENUM_ACCEPT);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_LANENUM_WAIT);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_COMPLETE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_CONFIGURAT
>ION_IDLE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_R
>CVRLOCK);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_S
>PEED);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_R
>CVRCFG);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_I
>DLE);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L0);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_ENTR
>Y);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_IDLE)
>;
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RX_L0S_FTS);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_ENTR
>Y);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_IDLE)
>;
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_TX_L0S_FTS);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L1_ENTRY);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L1_IDLE);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L2_IDLE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_L2_TRANSMI
>TWAKE);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_DISABLED);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_E
>NTRY_MASTER);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_A
>CTIVE_MASTER);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_E
>XIT_MASTER);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_E
>NTRY_SLAVE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_A
>CTIVE_SLAVE);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_LOOPBACK_E
>XIT_SLAVE);
>+	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_HOT_RESET);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_E
>QUALIZATION_PHASE_0);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_E
>QUALIZATION_PHASE_1);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_E
>QUALIZATION_PHASE_2);
>+
>	CDNS_PCIE_LGA_LTSSM_NAME(CDNS_PCIE_LGA_LTSSM_RECOVERY_E
>QUALIZATION_PHASE_3);
>+	default:
>+		str = "CDNS_PCIE_LGA_LTSSM_UNKNOWN";
>+		break;
>+	}
>+
>+	return str + strlen("CDNS_PCIE_LGA_LTSSM_");
>+}
>+
> static const char *cdns_pcie_hpa_ltssm_status_string(enum
>cdns_pcie_hpa_ltssm ltssm)
> {
> 	const char *str;
>@@ -158,6 +210,7 @@ static const char
>*cdns_pcie_hpa_ltssm_status_string(enum cdns_pcie_hpa_ltssm lt
> static int ltssm_status_show(struct seq_file *s, void *v)
> {
> 	struct cdns_pcie *pci = s->private;
>+	enum cdns_pcie_lga_ltssm lga_ltssm;
> 	enum cdns_pcie_hpa_ltssm hpa_ltssm;
> 	const char *str_ltssm;
> 	u32 val;
>@@ -168,11 +221,13 @@ static int ltssm_status_show(struct seq_file *s, void
>*v)
> 		hpa_ltssm =
>FIELD_GET(CDNS_PCIE_HPA_LTSSM_STATUS_MASK, val);
> 		str_ltssm = cdns_pcie_hpa_ltssm_status_string(hpa_ltssm);
> 	} else {
>-		/* TODO: LGA IP*/
>-		return 0;
>+		val = cdns_pcie_readl(pci, CDNS_PCIE_LM_BASE);
>+		lga_ltssm =
>FIELD_GET(CDNS_PCIE_LGA_LTSSM_STATUS_MASK, val);
>+		str_ltssm = cdns_pcie_lga_ltssm_status_string(lga_ltssm);
> 	}
>
>-	seq_printf(s, "%s (0x%02x)\n", str_ltssm, hpa_ltssm);
>+	seq_printf(s, "%s (0x%02x)\n", str_ltssm,
>+		   pci->is_hpa ? hpa_ltssm : lga_ltssm);
>
> 	return 0;
> }
>diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c
>b/drivers/pci/controller/cadence/pcie-cadence-ep.c
>index c0e1194a936b..370b19f4d38f 100644
>--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
>+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
>@@ -655,6 +655,7 @@ void cdns_pcie_ep_disable(struct cdns_pcie_ep *ep)
> 	struct device *dev = ep->pcie.dev;
> 	struct pci_epc *epc = to_pci_epc(dev);
>
>+	cdns_pcie_debugfs_deinit(&ep->pcie);
> 	pci_epc_deinit_notify(epc);
> 	pci_epc_mem_free_addr(epc, ep->irq_phys_addr, ep->irq_cpu_addr,
> 			      SZ_128K);
>@@ -761,6 +762,8 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
>
> 	pci_epc_init_notify(epc);
>
>+	cdns_pcie_debugfs_init(pcie);
>+
> 	return 0;
>
>  free_epc_mem:
>diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c
>b/drivers/pci/controller/cadence/pcie-cadence-host.c
>index 0bc9e6e90e0e..8105bb625eb7 100644
>--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
>+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
>@@ -364,6 +364,7 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
> {
> 	struct pci_host_bridge *bridge;
>
>+	cdns_pcie_debugfs_deinit(&rc->pcie);
> 	bridge = pci_host_bridge_from_priv(rc);
> 	pci_stop_root_bus(bridge->bus);
> 	pci_remove_root_bus(bridge->bus);
>@@ -423,7 +424,13 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> 	if (!bridge->ops)
> 		bridge->ops = &cdns_pcie_host_ops;
>
>-	return pci_host_probe(bridge);
>+	ret = pci_host_probe(bridge);
>+	if (ret)
>+		return ret;
>+
>+	cdns_pcie_debugfs_init(pcie);
>+
>+	return 0;
> }
> EXPORT_SYMBOL_GPL(cdns_pcie_host_setup);
>
>diff --git a/drivers/pci/controller/cadence/pcie-cadence.h
>b/drivers/pci/controller/cadence/pcie-cadence.h
>index 2320319af83b..8bc6564c65b9 100644
>--- a/drivers/pci/controller/cadence/pcie-cadence.h
>+++ b/drivers/pci/controller/cadence/pcie-cadence.h
>@@ -14,6 +14,7 @@
> #include "pcie-cadence-lga-regs.h"
> #include "pcie-cadence-hpa-regs.h"
>
>+#define CDNS_PCIE_LGA_LTSSM_STATUS_MASK	GENMASK(29, 24)
> #define CDNS_PCIE_HPA_LTSSM_STATUS_MASK	GENMASK(27, 20)
>
> enum cdns_pcie_rp_bar {
>@@ -44,6 +45,48 @@ enum cdns_pcie_reg_bank {
> 	REG_BANKS_MAX,
> };
>
>+enum cdns_pcie_lga_ltssm {
>+	CDNS_PCIE_LGA_LTSSM_DETECT_QUIET			= 0x00,
>+	CDNS_PCIE_LGA_LTSSM_DETECT_ACTIVE			= 0x01,
>+	CDNS_PCIE_LGA_LTSSM_POLLING_ACTIVE			= 0x02,
>+	CDNS_PCIE_LGA_LTSSM_POLLING_COMPLIANCE
>	= 0x03,
>+	CDNS_PCIE_LGA_LTSSM_POLLING_CONFIGURATION		= 0x04,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_START	= 0x05,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LINKWIDTH_ACCEPT
>	= 0x06,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_ACCEPT	= 0x07,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_LANENUM_WAIT
>	= 0x08,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_COMPLETE		= 0x09,
>+	CDNS_PCIE_LGA_LTSSM_CONFIGURATION_IDLE
>	= 0x0A,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRLOCK			= 0x0B,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_SPEED			= 0x0C,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_RCVRCFG			= 0x0D,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_IDLE			= 0x0E,
>+	CDNS_PCIE_LGA_LTSSM_L0					= 0x10,
>+	CDNS_PCIE_LGA_LTSSM_RX_L0S_ENTRY			= 0x11,
>+	CDNS_PCIE_LGA_LTSSM_RX_L0S_IDLE				= 0x12,
>+	CDNS_PCIE_LGA_LTSSM_RX_L0S_FTS				= 0x13,
>+	CDNS_PCIE_LGA_LTSSM_TX_L0S_ENTRY			= 0x14,
>+	CDNS_PCIE_LGA_LTSSM_TX_L0S_IDLE				= 0x15,
>+	CDNS_PCIE_LGA_LTSSM_TX_L0S_FTS				= 0x16,
>+	CDNS_PCIE_LGA_LTSSM_L1_ENTRY				= 0x17,
>+	CDNS_PCIE_LGA_LTSSM_L1_IDLE				= 0x18,
>+	CDNS_PCIE_LGA_LTSSM_L2_IDLE				= 0x19,
>+	CDNS_PCIE_LGA_LTSSM_L2_TRANSMITWAKE			= 0x1A,
>+	CDNS_PCIE_LGA_LTSSM_DISABLED				= 0x20,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_MASTER		= 0x21,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_MASTER		= 0x22,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_MASTER		= 0x23,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ENTRY_SLAVE		= 0x24,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_ACTIVE_SLAVE		= 0x25,
>+	CDNS_PCIE_LGA_LTSSM_LOOPBACK_EXIT_SLAVE
>	= 0x26,
>+	CDNS_PCIE_LGA_LTSSM_HOT_RESET				= 0x27,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_0	= 0x28,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_1	= 0x29,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_2	= 0x2A,
>+	CDNS_PCIE_LGA_LTSSM_RECOVERY_EQUALIZATION_PHASE_3	= 0x2B,
>+	CDNS_PCIE_LGA_LTSSM_UNKNOWN				=
>0xFFFFFFFF,
>+};
>+
> enum cdns_pcie_hpa_ltssm {
> 	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET		= 0,
> 	CDNS_PCIE_HPA_LTSSM_DETECT_QUIET_ENTRY		= 1,
>--
>2.43.0


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-20  2:34   ` Manikandan Karunakaran Pillai
@ 2026-05-20  2:59     ` Hans Zhang
  2026-05-20  4:36       ` Aksh Garg
  0 siblings, 1 reply; 13+ messages in thread
From: Hans Zhang @ 2026-05-20  2:59 UTC (permalink / raw)
  To: Manikandan Karunakaran Pillai, bhelgaas@google.com,
	lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, a-garg7@ti.com, s-vadapalli@ti.com,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org



On 5/20/26 10:34, Manikandan Karunakaran Pillai wrote:
>> EXTERNAL MAIL
>>
>>
>> Extend debugfs support to LGA-based Cadence PCIe controllers. The
>> 'ltssm_status' file now works for both HPA and LGA IP by selecting the
>> appropriate register access based on the 'is_hpa' flag.
>>
>> Signed-off-by: Hans Zhang <18255117159@163.com>
>> ---
>> .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
>> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
>> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
>> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
>> 4 files changed, 112 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> index 97c5deef2b1a..0a308f95e9f6 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>> @@ -13,6 +13,58 @@
>>
>> #define CDNS_DEBUGFS_BUF_MAX		128
> 
> Where is CDNS_DEBUGFS_BUF_MAX used for ?

Hi Manikandan,

Thank you very much for your reply and reminder.

This macro definition was used in patch 0002. Since I compiled the code 
after applying all three patches together, I didn't notice this issue. 
The next version will be fixed and will be included in patch 0002.

Best regards,
Hans


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-20  2:59     ` Hans Zhang
@ 2026-05-20  4:36       ` Aksh Garg
  2026-05-20  4:40         ` Hans Zhang
  0 siblings, 1 reply; 13+ messages in thread
From: Aksh Garg @ 2026-05-20  4:36 UTC (permalink / raw)
  To: Hans Zhang, Manikandan Karunakaran Pillai, bhelgaas@google.com,
	lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, s-vadapalli@ti.com, linux-pci@vger.kernel.org,
	linux-kernel@vger.kernel.org



On 20/05/26 08:29, Hans Zhang wrote:
> 
> 
> On 5/20/26 10:34, Manikandan Karunakaran Pillai wrote:
>>> EXTERNAL MAIL
>>>
>>>
>>> Extend debugfs support to LGA-based Cadence PCIe controllers. The
>>> 'ltssm_status' file now works for both HPA and LGA IP by selecting the
>>> appropriate register access based on the 'is_hpa' flag.
>>>
>>> Signed-off-by: Hans Zhang <18255117159@163.com>
>>> ---
>>> .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
>>> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
>>> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
>>> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
>>> 4 files changed, 112 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>> b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>> index 97c5deef2b1a..0a308f95e9f6 100644
>>> --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>> @@ -13,6 +13,58 @@
>>>
>>> #define CDNS_DEBUGFS_BUF_MAX        128
>>
>> Where is CDNS_DEBUGFS_BUF_MAX used for ?
> 
> Hi Manikandan,
> 
> Thank you very much for your reply and reminder.
> 
> This macro definition was used in patch 0002. Since I compiled the code 
> after applying all three patches together, I didn't notice this issue. 
> The next version will be fixed and will be included in patch 0002.

I didn't understood the issue here. The macro definition was indeed 
introduced in patch 0002 itself right? Am I missing something here?

> 
> Best regards,
> Hans
> 


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-20  4:36       ` Aksh Garg
@ 2026-05-20  4:40         ` Hans Zhang
  2026-05-20  5:27           ` Aksh Garg
  0 siblings, 1 reply; 13+ messages in thread
From: Hans Zhang @ 2026-05-20  4:40 UTC (permalink / raw)
  To: Aksh Garg, Manikandan Karunakaran Pillai, bhelgaas@google.com,
	lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, s-vadapalli@ti.com, linux-pci@vger.kernel.org,
	linux-kernel@vger.kernel.org



On 5/20/26 12:36, Aksh Garg wrote:
> 
> 
> On 20/05/26 08:29, Hans Zhang wrote:
>>
>>
>> On 5/20/26 10:34, Manikandan Karunakaran Pillai wrote:
>>>> EXTERNAL MAIL
>>>>
>>>>
>>>> Extend debugfs support to LGA-based Cadence PCIe controllers. The
>>>> 'ltssm_status' file now works for both HPA and LGA IP by selecting the
>>>> appropriate register access based on the 'is_hpa' flag.
>>>>
>>>> Signed-off-by: Hans Zhang <18255117159@163.com>
>>>> ---
>>>> .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
>>>> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
>>>> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
>>>> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
>>>> 4 files changed, 112 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>> b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>> index 97c5deef2b1a..0a308f95e9f6 100644
>>>> --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>> @@ -13,6 +13,58 @@
>>>>
>>>> #define CDNS_DEBUGFS_BUF_MAX        128
>>>
>>> Where is CDNS_DEBUGFS_BUF_MAX used for ?
>>
>> Hi Manikandan,
>>
>> Thank you very much for your reply and reminder.
>>
>> This macro definition was used in patch 0002. Since I compiled the 
>> code after applying all three patches together, I didn't notice this 
>> issue. The next version will be fixed and will be included in patch 0002.
> 
> I didn't understood the issue here. The macro definition was indeed 
> introduced in patch 0002 itself right? Am I missing something here?

Hi Aksh,

If only patches 0001 and 0002 are applied, there will be a compilation 
error. Patch 0002 will fail to find CDNS_DEBUGFS_BUF_MAX. Previously, I 
split LGA into patch 0003. I didn't notice this issue. Do you think I 
have explained it clearly?

Best regards,
Hans


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-20  4:40         ` Hans Zhang
@ 2026-05-20  5:27           ` Aksh Garg
  2026-05-20  5:44             ` Hans Zhang
  0 siblings, 1 reply; 13+ messages in thread
From: Aksh Garg @ 2026-05-20  5:27 UTC (permalink / raw)
  To: Hans Zhang, Manikandan Karunakaran Pillai, bhelgaas@google.com,
	lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, s-vadapalli@ti.com, linux-pci@vger.kernel.org,
	linux-kernel@vger.kernel.org



On 20/05/26 10:10, Hans Zhang wrote:
> 
> 
> On 5/20/26 12:36, Aksh Garg wrote:
>>
>>
>> On 20/05/26 08:29, Hans Zhang wrote:
>>>
>>>
>>> On 5/20/26 10:34, Manikandan Karunakaran Pillai wrote:
>>>>> EXTERNAL MAIL
>>>>>
>>>>>
>>>>> Extend debugfs support to LGA-based Cadence PCIe controllers. The
>>>>> 'ltssm_status' file now works for both HPA and LGA IP by selecting the
>>>>> appropriate register access based on the 'is_hpa' flag.
>>>>>
>>>>> Signed-off-by: Hans Zhang <18255117159@163.com>
>>>>> ---
>>>>> .../controller/cadence/pcie-cadence-debugfs.c | 61 ++++++++++++++++++-
>>>>> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
>>>>> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
>>>>> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
>>>>> 4 files changed, 112 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>> b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>> index 97c5deef2b1a..0a308f95e9f6 100644
>>>>> --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>> @@ -13,6 +13,58 @@
>>>>>
>>>>> #define CDNS_DEBUGFS_BUF_MAX        128
>>>>
>>>> Where is CDNS_DEBUGFS_BUF_MAX used for ?
>>>
>>> Hi Manikandan,
>>>
>>> Thank you very much for your reply and reminder.
>>>
>>> This macro definition was used in patch 0002. Since I compiled the 
>>> code after applying all three patches together, I didn't notice this 
>>> issue. The next version will be fixed and will be included in patch 
>>> 0002.
>>
>> I didn't understood the issue here. The macro definition was indeed 
>> introduced in patch 0002 itself right? Am I missing something here?
> 
> Hi Aksh,
> 
> If only patches 0001 and 0002 are applied, there will be a compilation 
> error. Patch 0002 will fail to find CDNS_DEBUGFS_BUF_MAX. Previously, I 
> split LGA into patch 0003. I didn't notice this issue. Do you think I 
> have explained it clearly?

I see no compilation errors after applying only patch 1 and 2.
CDNS_DEBUGFS_BUF_MAX macro is defined in the patch 2 itself.

Patch 3 just uses the CDNS_DEBUGFS_BUF_MAX macro definition code for the 
reference point to add the new code lines in that patch, it didn't 
introduced the macro here.

> 
> Best regards,
> Hans
> 


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 3/3] PCI: cadence: Add LGA IP debugfs for LTSSM status
  2026-05-20  5:27           ` Aksh Garg
@ 2026-05-20  5:44             ` Hans Zhang
  0 siblings, 0 replies; 13+ messages in thread
From: Hans Zhang @ 2026-05-20  5:44 UTC (permalink / raw)
  To: Aksh Garg, Manikandan Karunakaran Pillai, bhelgaas@google.com,
	lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org
  Cc: robh@kernel.org, s-vadapalli@ti.com, linux-pci@vger.kernel.org,
	linux-kernel@vger.kernel.org



On 5/20/26 13:27, Aksh Garg wrote:
> 
> 
> On 20/05/26 10:10, Hans Zhang wrote:
>>
>>
>> On 5/20/26 12:36, Aksh Garg wrote:
>>>
>>>
>>> On 20/05/26 08:29, Hans Zhang wrote:
>>>>
>>>>
>>>> On 5/20/26 10:34, Manikandan Karunakaran Pillai wrote:
>>>>>> EXTERNAL MAIL
>>>>>>
>>>>>>
>>>>>> Extend debugfs support to LGA-based Cadence PCIe controllers. The
>>>>>> 'ltssm_status' file now works for both HPA and LGA IP by selecting 
>>>>>> the
>>>>>> appropriate register access based on the 'is_hpa' flag.
>>>>>>
>>>>>> Signed-off-by: Hans Zhang <18255117159@163.com>
>>>>>> ---
>>>>>> .../controller/cadence/pcie-cadence-debugfs.c | 61 +++++++++++++++ 
>>>>>> +++-
>>>>>> .../pci/controller/cadence/pcie-cadence-ep.c  |  3 +
>>>>>> .../controller/cadence/pcie-cadence-host.c    |  9 ++-
>>>>>> drivers/pci/controller/cadence/pcie-cadence.h | 43 +++++++++++++
>>>>>> 4 files changed, 112 insertions(+), 4 deletions(-)
>>>>>>
>>>>>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>>> b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>>> index 97c5deef2b1a..0a308f95e9f6 100644
>>>>>> --- a/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>>> +++ b/drivers/pci/controller/cadence/pcie-cadence-debugfs.c
>>>>>> @@ -13,6 +13,58 @@
>>>>>>
>>>>>> #define CDNS_DEBUGFS_BUF_MAX        128
>>>>>
>>>>> Where is CDNS_DEBUGFS_BUF_MAX used for ?
>>>>
>>>> Hi Manikandan,
>>>>
>>>> Thank you very much for your reply and reminder.
>>>>
>>>> This macro definition was used in patch 0002. Since I compiled the 
>>>> code after applying all three patches together, I didn't notice this 
>>>> issue. The next version will be fixed and will be included in patch 
>>>> 0002.
>>>
>>> I didn't understood the issue here. The macro definition was indeed 
>>> introduced in patch 0002 itself right? Am I missing something here?
>>
>> Hi Aksh,
>>
>> If only patches 0001 and 0002 are applied, there will be a compilation 
>> error. Patch 0002 will fail to find CDNS_DEBUGFS_BUF_MAX. Previously, 
>> I split LGA into patch 0003. I didn't notice this issue. Do you think 
>> I have explained it clearly?
> 
> I see no compilation errors after applying only patch 1 and 2.
> CDNS_DEBUGFS_BUF_MAX macro is defined in the patch 2 itself.
> 
> Patch 3 just uses the CDNS_DEBUGFS_BUF_MAX macro definition code for the 
> reference point to add the new code lines in that patch, it didn't 
> introduced the macro here.

Hi Aksh,

Well, I was misled. Could you please help test this series of patches? 
If there are no issues, please add your test label.

Best regards,
Hans




^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status
  2026-05-19 12:36 ` [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status Hans Zhang
  2026-05-19 13:20   ` sashiko-bot
@ 2026-05-20  7:26   ` Aksh Garg
  2026-05-20 14:54     ` Hans Zhang
  1 sibling, 1 reply; 13+ messages in thread
From: Aksh Garg @ 2026-05-20  7:26 UTC (permalink / raw)
  To: Hans Zhang, bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, s-vadapalli, linux-pci, linux-kernel



On 19/05/26 18:06, Hans Zhang wrote:
> Add debugfs support for HPA-based Cadence PCIe controllers. A new file
> 'ltssm_status' is created under debugfs, allowing users to read the
> current LTSSM state as a string and raw value.
> 
> Signed-off-by: Hans Zhang <18255117159@163.com>
> ---
>   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     |   4 +
>   .../controller/cadence/pcie-cadence-debugfs.c | 208 ++++++++++++++++++
>   .../cadence/pcie-cadence-host-hpa.c           |  19 +-
>   drivers/pci/controller/cadence/pcie-cadence.h | 153 +++++++++++++
>   7 files changed, 398 insertions(+), 1 deletion(-)
>   create mode 100644 Documentation/ABI/testing/debugfs-cdns-pcie
>   create mode 100644 drivers/pci/controller/cadence/pcie-cadence-debugfs.c
> 
> diff --git a/Documentation/ABI/testing/debugfs-cdns-pcie b/Documentation/ABI/testing/debugfs-cdns-pcie
> new file mode 100644
> index 000000000000..c1104e28e4ee
> --- /dev/null
> +++ b/Documentation/ABI/testing/debugfs-cdns-pcie
> @@ -0,0 +1,5 @@
> +What:		/sys/kernel/debug/cdns_pcie_<dev>/ltssm_status
> +Date:		March 2026
> +Contact:	Hans Zhang <18255117159@163.com>
> +Description:	(RO) Read will return the current PCIe LTSSM state in both
> +		string and raw value.
> \ No newline at end of file
> diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/controller/cadence/Kconfig
> index 9e651d545973..cb010bc97aad 100644
> --- a/drivers/pci/controller/cadence/Kconfig
> +++ b/drivers/pci/controller/cadence/Kconfig
> @@ -6,6 +6,15 @@ menu "Cadence-based PCIe controllers"
>   config PCIE_CADENCE
>   	tristate
>   
> +config PCIE_CADENCE_DEBUGFS
> +	tristate "Cadence PCIe debugfs entries"
> +	depends on DEBUG_FS
> +	depends on PCIE_CADENCE_HOST || PCIE_CADENCE_EP
> +	help
> +	  Say Y here to enable debugfs entries for the PCIe controller. These
> +	  entries provide various debug features related to the controller and
> +	  the LTSSM status of link can be displayed.
> +
>   config PCIE_CADENCE_HOST
>   	tristate
>   	depends on OF

Sashiko pointed the compilation issues when this is build as a module.
The linkage issue needs to be resolved if we want this as a module.
Also, if we build it as m, it would requires MODULE_LICENSE() and 
MODULE_DESCRIPTION().

> diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/controller/cadence/Makefile
> index b8ec1cecfaa8..2cdc4617e0c2 100644
> --- a/drivers/pci/controller/cadence/Makefile
> +++ b/drivers/pci/controller/cadence/Makefile
> @@ -4,6 +4,7 @@ pcie-cadence-host-mod-y := pcie-cadence-host-common.o pcie-cadence-host.o pcie-c
>   pcie-cadence-ep-mod-y := pcie-cadence-ep.o
>   
>   obj-$(CONFIG_PCIE_CADENCE) = pcie-cadence-mod.o
> +obj-$(CONFIG_PCIE_CADENCE_DEBUGFS) += pcie-cadence-debugfs.o
>   obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host-mod.o
>   obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep-mod.o
>   obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
> diff --git a/drivers/pci/controller/cadence/pci-sky1.c b/drivers/pci/controller/cadence/pci-sky1.c
> index e1f4a98e2ab6..b8632f1d3156 100644
> --- a/drivers/pci/controller/cadence/pci-sky1.c
> +++ b/drivers/pci/controller/cadence/pci-sky1.c
> @@ -221,6 +221,10 @@ MODULE_DEVICE_TABLE(of, of_sky1_pcie_match);

[ ... ]

>   /**
> @@ -447,6 +583,7 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc);
>   void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
>   			       int where);
>   int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc *rc);
> +void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc);
>   #else
>   static inline int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
>   {
> @@ -472,6 +609,10 @@ static inline void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
>   {
>   }
>   
> +static inline void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc)
> +{
> +}
> +
>   static inline void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
>   					     int where)
>   {
> @@ -535,4 +676,16 @@ bool cdns_pcie_hpa_link_up(struct cdns_pcie *pcie);
>   
>   extern const struct dev_pm_ops cdns_pcie_pm_ops;
>   
> +#ifdef CONFIG_PCIE_CADENCE_DEBUGFS

Use "#if IS_ENABLED(CONFIG_PCIE_CADENCE_DEBUGFS)" to resolve the 
compilation error when building as a module.

> +void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci);
> +void cdns_pcie_debugfs_init(struct cdns_pcie *pci);
> +#else
> +static inline void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
> +{
> +}
> +static inline void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
> +{
> +}
> +#endif
> +
>   #endif /* _PCIE_CADENCE_H */


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status
  2026-05-20  7:26   ` Aksh Garg
@ 2026-05-20 14:54     ` Hans Zhang
  0 siblings, 0 replies; 13+ messages in thread
From: Hans Zhang @ 2026-05-20 14:54 UTC (permalink / raw)
  To: Aksh Garg, bhelgaas, lpieralisi, kwilczynski, mani
  Cc: robh, mpillai, s-vadapalli, linux-pci, linux-kernel



On 5/20/26 15:26, Aksh Garg wrote:
> 
> 
> On 19/05/26 18:06, Hans Zhang wrote:
>> Add debugfs support for HPA-based Cadence PCIe controllers. A new file
>> 'ltssm_status' is created under debugfs, allowing users to read the
>> current LTSSM state as a string and raw value.
>>
>> Signed-off-by: Hans Zhang <18255117159@163.com>
>> ---
>>   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     |   4 +
>>   .../controller/cadence/pcie-cadence-debugfs.c | 208 ++++++++++++++++++
>>   .../cadence/pcie-cadence-host-hpa.c           |  19 +-
>>   drivers/pci/controller/cadence/pcie-cadence.h | 153 +++++++++++++
>>   7 files changed, 398 insertions(+), 1 deletion(-)
>>   create mode 100644 Documentation/ABI/testing/debugfs-cdns-pcie
>>   create mode 100644 drivers/pci/controller/cadence/pcie-cadence- 
>> debugfs.c
>>
>> diff --git a/Documentation/ABI/testing/debugfs-cdns-pcie b/ 
>> Documentation/ABI/testing/debugfs-cdns-pcie
>> new file mode 100644
>> index 000000000000..c1104e28e4ee
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/debugfs-cdns-pcie
>> @@ -0,0 +1,5 @@
>> +What:        /sys/kernel/debug/cdns_pcie_<dev>/ltssm_status
>> +Date:        March 2026
>> +Contact:    Hans Zhang <18255117159@163.com>
>> +Description:    (RO) Read will return the current PCIe LTSSM state in 
>> both
>> +        string and raw value.
>> \ No newline at end of file
>> diff --git a/drivers/pci/controller/cadence/Kconfig b/drivers/pci/ 
>> controller/cadence/Kconfig
>> index 9e651d545973..cb010bc97aad 100644
>> --- a/drivers/pci/controller/cadence/Kconfig
>> +++ b/drivers/pci/controller/cadence/Kconfig
>> @@ -6,6 +6,15 @@ menu "Cadence-based PCIe controllers"
>>   config PCIE_CADENCE
>>       tristate
>> +config PCIE_CADENCE_DEBUGFS
>> +    tristate "Cadence PCIe debugfs entries"
>> +    depends on DEBUG_FS
>> +    depends on PCIE_CADENCE_HOST || PCIE_CADENCE_EP
>> +    help
>> +      Say Y here to enable debugfs entries for the PCIe controller. 
>> These
>> +      entries provide various debug features related to the 
>> controller and
>> +      the LTSSM status of link can be displayed.
>> +
>>   config PCIE_CADENCE_HOST
>>       tristate
>>       depends on OF
> 
> Sashiko pointed the compilation issues when this is build as a module.
> The linkage issue needs to be resolved if we want this as a module.
> Also, if we build it as m, it would requires MODULE_LICENSE() and 
> MODULE_DESCRIPTION().

Hi Aksh,

Will add.


> 
>> diff --git a/drivers/pci/controller/cadence/Makefile b/drivers/pci/ 
>> controller/cadence/Makefile
>> index b8ec1cecfaa8..2cdc4617e0c2 100644
>> --- a/drivers/pci/controller/cadence/Makefile
>> +++ b/drivers/pci/controller/cadence/Makefile
>> @@ -4,6 +4,7 @@ pcie-cadence-host-mod-y := pcie-cadence-host-common.o 
>> pcie-cadence-host.o pcie-c
>>   pcie-cadence-ep-mod-y := pcie-cadence-ep.o
>>   obj-$(CONFIG_PCIE_CADENCE) = pcie-cadence-mod.o
>> +obj-$(CONFIG_PCIE_CADENCE_DEBUGFS) += pcie-cadence-debugfs.o
>>   obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host-mod.o
>>   obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep-mod.o
>>   obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
>> diff --git a/drivers/pci/controller/cadence/pci-sky1.c b/drivers/pci/ 
>> controller/cadence/pci-sky1.c
>> index e1f4a98e2ab6..b8632f1d3156 100644
>> --- a/drivers/pci/controller/cadence/pci-sky1.c
>> +++ b/drivers/pci/controller/cadence/pci-sky1.c
>> @@ -221,6 +221,10 @@ MODULE_DEVICE_TABLE(of, of_sky1_pcie_match);
> 
> [ ... ]
> 
>>   /**
>> @@ -447,6 +583,7 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc);
>>   void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
>>                      int where);
>>   int cdns_pcie_hpa_host_setup(struct cdns_pcie_rc *rc);
>> +void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc);
>>   #else
>>   static inline int cdns_pcie_host_link_setup(struct cdns_pcie_rc *rc)
>>   {
>> @@ -472,6 +609,10 @@ static inline void cdns_pcie_host_disable(struct 
>> cdns_pcie_rc *rc)
>>   {
>>   }
>> +static inline void cdns_pcie_hpa_host_disable(struct cdns_pcie_rc *rc)
>> +{
>> +}
>> +
>>   static inline void __iomem *cdns_pci_map_bus(struct pci_bus *bus, 
>> unsigned int devfn,
>>                            int where)
>>   {
>> @@ -535,4 +676,16 @@ bool cdns_pcie_hpa_link_up(struct cdns_pcie *pcie);
>>   extern const struct dev_pm_ops cdns_pcie_pm_ops;
>> +#ifdef CONFIG_PCIE_CADENCE_DEBUGFS
> 
> Use "#if IS_ENABLED(CONFIG_PCIE_CADENCE_DEBUGFS)" to resolve the 
> compilation error when building as a module.
> 

Will change.

Best regards,
Hans

>> +void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci);
>> +void cdns_pcie_debugfs_init(struct cdns_pcie *pci);
>> +#else
>> +static inline void cdns_pcie_debugfs_deinit(struct cdns_pcie *pci)
>> +{
>> +}
>> +static inline void cdns_pcie_debugfs_init(struct cdns_pcie *pci)
>> +{
>> +}
>> +#endif
>> +
>>   #endif /* _PCIE_CADENCE_H */


^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2026-05-20 14:55 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-05-19 12:36 [PATCH v6 0/3] PCI: cadence: Add LTSSM debugfs Hans Zhang
2026-05-19 12:36 ` [PATCH v6 1/3] PCI: cadence: Add HPA architecture flag Hans Zhang
2026-05-19 12:36 ` [PATCH v6 2/3] PCI: cadence: Add HPA IP debugfs for LTSSM status Hans Zhang
2026-05-19 13:20   ` sashiko-bot
2026-05-20  7:26   ` Aksh Garg
2026-05-20 14:54     ` Hans Zhang
2026-05-19 12:36 ` [PATCH v6 3/3] PCI: cadence: Add LGA " Hans Zhang
2026-05-20  2:34   ` Manikandan Karunakaran Pillai
2026-05-20  2:59     ` Hans Zhang
2026-05-20  4:36       ` Aksh Garg
2026-05-20  4:40         ` Hans Zhang
2026-05-20  5:27           ` Aksh Garg
2026-05-20  5:44             ` Hans Zhang

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