[v2] PCI: dwc: Add PCIe event counters for groups 5 to 7 in DWC debugfs
From: Hans Zhang
Date: Fri Mar 06 2026 - 10:16:06 EST
Extend the DesignWare PCIe controller's debugfs statistical counter
interface with event definitions from groups 5 through 7 as documented
in the DWC PCIe Databook (version 3.30a, section 3.8.2.3, Tables 3-59,
3-60, 3-61). These counters provide visibility into Layer1 non-error
events (link state transitions,ASPM, L1 substates), Layer2 DLLP
exchanges, and Layer3 TLP transactions.
The counters are exposed under the debugfs statistical counter directory,
allowing users to monitor link behavior and diagnose PCIe protocol issues
more effectively.
Co-developed-by: Cheng Xin <chengqin195275@xxxxxxx>
Signed-off-by: Cheng Xin <chengqin195275@xxxxxxx>
Signed-off-by: Hans Zhang <18255117159@xxxxxxx>
---
Thank you, Cheng Xin, for providing the 3.30a version of the DWC PCIe Data Book.
Changes for v2:
- Sorry, I sent the patch multiple times in a row. The first version of
the email was incorrect. The email address of Cheng Xin has been corrected.
---
.../controller/dwc/pcie-designware-debugfs.c | 52 ++++++++++++++++++-
1 file changed, 51 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-debugfs.c b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
index 0d1340c9b364..2efddb21b2b2 100644
--- a/drivers/pci/controller/dwc/pcie-designware-debugfs.c
+++ b/drivers/pci/controller/dwc/pcie-designware-debugfs.c
@@ -131,13 +131,16 @@ static const u32 err_inj_type_mask[] = {
* supported in DWC RAS DES
* @name: Name of the error counter
* @group_no: Group number that the event belongs to. The value can range
- * from 0 to 4
+ * from 0 to 7
* @event_no: Event number of the particular event. The value ranges are:
* Group 0: 0 - 10
* Group 1: 5 - 13
* Group 2: 0 - 7
* Group 3: 0 - 5
* Group 4: 0 - 1
+ * Group 5: 0 - 13
+ * Group 6: 0 - 6
+ * Group 7: 0 - 25
*/
struct dwc_pcie_event_counter {
const char *name;
@@ -181,6 +184,53 @@ static const struct dwc_pcie_event_counter event_list[] = {
{"completion_timeout", 0x3, 0x5},
{"ebuf_skp_add", 0x4, 0x0},
{"ebuf_skp_del", 0x4, 0x1},
+ {"l0_to_recovery_entry", 0x5, 0x0},
+ {"l1_to_recovery_entry", 0x5, 0x1},
+ {"tx_l0s_entry", 0x5, 0x2},
+ {"rx_l0s_entry", 0x5, 0x3},
+ {"aspm_l1_reject", 0x5, 0x4},
+ {"l1_entry", 0x5, 0x5},
+ {"l1_cpm", 0x5, 0x6},
+ {"l1.1_entry", 0x5, 0x7},
+ {"l1.2_entry", 0x5, 0x8},
+ {"l1_short_duration", 0x5, 0x9},
+ {"l1.2_abort", 0x5, 0xa},
+ {"l2_entry", 0x5, 0xb},
+ {"speed_change", 0x5, 0xc},
+ {"link_width_change", 0x5, 0xd},
+ {"tx_ack_dllp", 0x6, 0x0},
+ {"tx_update_fc_dllp", 0x6, 0x1},
+ {"rx_ack_dllp", 0x6, 0x2},
+ {"rx_update_fc_dllp", 0x6, 0x3},
+ {"rx_nullified_tlp", 0x6, 0x4},
+ {"tx_nullified_tlp", 0x6, 0x5},
+ {"rx_duplicate_tlp", 0x6, 0x6},
+ {"tx_memory_write", 0x7, 0x0},
+ {"tx_memory_read", 0x7, 0x1},
+ {"tx_configuration_write", 0x7, 0x2},
+ {"tx_configuration_read", 0x7, 0x3},
+ {"tx_io_write", 0x7, 0x4},
+ {"tx_io_read", 0x7, 0x5},
+ {"tx_completion_without_data", 0x7, 0x6},
+ {"tx_completion_w_data", 0x7, 0x7},
+ {"tx_message_tlp_pcie_vc_only", 0x7, 0x8},
+ {"tx_atomic", 0x7, 0x9},
+ {"tx_tlp_with_prefix", 0x7, 0xa},
+ {"rx_memory_write", 0x7, 0xb},
+ {"rx_memory_read", 0x7, 0xc},
+ {"rx_configuration_write", 0x7, 0xd},
+ {"rx_configuration_read", 0x7, 0xe},
+ {"rx_io_write", 0x7, 0xf},
+ {"rx_io_read", 0x7, 0x10},
+ {"rx_completion_without_data", 0x7, 0x11},
+ {"rx_completion_w_data", 0x7, 0x12},
+ {"rx_message_tlp_pcie_vc_only", 0x7, 0x13},
+ {"rx_atomic", 0x7, 0x14},
+ {"rx_tlp_with_prefix", 0x7, 0x15},
+ {"tx_ccix_tlp", 0x7, 0x16},
+ {"rx_ccix_tlp", 0x7, 0x17},
+ {"tx_deferrable_memory_write_tlp", 0x7, 0x18},
+ {"rx_deferrable_memory_write_tlp", 0x7, 0x19},
};
static ssize_t lane_detect_read(struct file *file, char __user *buf,
base-commit: 5ee8dbf54602dc340d6235b1d6aa17c0f283f48c
--
2.34.1