Re: [PATCH v3] PCI: dwc: Add PCIe event counters for groups 5 to 7 in DWC debugfs

[Hans Zhang <18255117159@163.com>]

[+cc Shawn]

On 3/7/26 10:01, Hans Zhang wrote:
> 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 6.30a, 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@126.com>
> Signed-off-by: Cheng Xin <chengqin195275@126.com>
> Signed-off-by: Hans Zhang <18255117159@163.com>
> ---
> Thank you, Cheng Xin, for providing the 6.30a version of the DWC PCIe Data Book.
> 
> Changes for v3:
> - Correct the incorrect version information of the databook. Thank you, Shawn, for the reminder.
> 
> 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: 325a118c12045239076b7ea9e66391dd6f56f72e