Commit 25ba596d authored by Sanman Pradhan's avatar Sanman Pradhan Committed by Jakub Kicinski
Browse files

eth: fbnic: add PCIe hardware statistics 



Add PCIe hardware statistics support to the fbnic driver. These stats
provide insight into PCIe transaction performance and error conditions.

Which includes, read/write and completion TLP counts and DWORD counts and
debug counters for tag, completion credit and NP credit exhaustion

The stats are exposed via debugfs and can be used to monitor PCIe
performance and debug PCIe issues.

Signed-off-by: default avatarSanman Pradhan <sanman.p211993@gmail.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20241115015344.757567-5-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 08606cb5

Documentation/networking/device_drivers/ethernet/meta/fbnic.rst

+30 −0
Original line number Diff line number Diff line
@@ -27,3 +27,33 @@ driver takes over. 
devlink dev info provides version information for all three components. In

addition to the version the hg commit hash of the build is included as a

separate entry.



Statistics

----------



PCIe

~~~~



The fbnic driver exposes PCIe hardware performance statistics through debugfs

(``pcie_stats``). These statistics provide insights into PCIe transaction

behavior and potential performance bottlenecks.



1. PCIe Transaction Counters:



   These counters track PCIe transaction activity:

        - ``pcie_ob_rd_tlp``: Outbound read Transaction Layer Packets count

        - ``pcie_ob_rd_dword``: DWORDs transferred in outbound read transactions

        - ``pcie_ob_wr_tlp``: Outbound write Transaction Layer Packets count

        - ``pcie_ob_wr_dword``: DWORDs transferred in outbound write

	  transactions

        - ``pcie_ob_cpl_tlp``: Outbound completion TLP count

        - ``pcie_ob_cpl_dword``: DWORDs transferred in outbound completion TLPs



2. PCIe Resource Monitoring:



   These counters indicate PCIe resource exhaustion events:

        - ``pcie_ob_rd_no_tag``: Read requests dropped due to tag unavailability

        - ``pcie_ob_rd_no_cpl_cred``: Read requests dropped due to completion

	  credit exhaustion

        - ``pcie_ob_rd_no_np_cred``: Read requests dropped due to non-posted

	  credit exhaustion

drivers/net/ethernet/meta/fbnic/fbnic_csr.h

+37 −0
Original line number Diff line number Diff line
@@ -918,6 +918,43 @@ enum { 
#define FBNIC_MAX_QUEUES		128

#define FBNIC_CSR_END_QUEUE	(0x40000 + 0x400 * FBNIC_MAX_QUEUES - 1)



/* PUL User Registers*/

#define FBNIC_PUL_USER_OB_RD_TLP_CNT_31_0 \

					0x3106e		/* 0xc41b8 */

#define FBNIC_PUL_USER_OB_RD_DWORD_CNT_31_0 \

					0x31070		/* 0xc41c0 */

#define FBNIC_PUL_USER_OB_RD_DWORD_CNT_63_32 \

					0x31071		/* 0xc41c4 */

#define FBNIC_PUL_USER_OB_WR_TLP_CNT_31_0 \

					0x31072		/* 0xc41c8 */

#define FBNIC_PUL_USER_OB_WR_TLP_CNT_63_32 \

					0x31073		/* 0xc41cc */

#define FBNIC_PUL_USER_OB_WR_DWORD_CNT_31_0 \

					0x31074		/* 0xc41d0 */

#define FBNIC_PUL_USER_OB_WR_DWORD_CNT_63_32 \

					0x31075		/* 0xc41d4 */

#define FBNIC_PUL_USER_OB_CPL_TLP_CNT_31_0 \

					0x31076		/* 0xc41d8 */

#define FBNIC_PUL_USER_OB_CPL_TLP_CNT_63_32 \

					0x31077		/* 0xc41dc */

#define FBNIC_PUL_USER_OB_CPL_DWORD_CNT_31_0 \

					0x31078		/* 0xc41e0 */

#define FBNIC_PUL_USER_OB_CPL_DWORD_CNT_63_32 \

					0x31079		/* 0xc41e4 */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_CPL_CRED_31_0 \

					0x3107a		/* 0xc41e8 */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_CPL_CRED_63_32 \

					0x3107b		/* 0xc41ec */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_TAG_31_0 \

					0x3107c		/* 0xc41f0 */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_TAG_63_32 \

					0x3107d		/* 0xc41f4 */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_NP_CRED_31_0 \

					0x3107e		/* 0xc41f8 */

#define FBNIC_PUL_USER_OB_RD_DBG_CNT_NP_CRED_63_32 \

					0x3107f		/* 0xc41fc */

#define FBNIC_CSR_END_PUL_USER	0x31080	/* CSR section delimiter */



/* BAR 4 CSRs */



/* The IPC mailbox consists of 32 mailboxes, with each mailbox consisting

drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c

+34 −0
Original line number Diff line number Diff line
@@ -3,17 +3,51 @@ 


#include <linux/debugfs.h>

#include <linux/pci.h>

#include <linux/rtnetlink.h>

#include <linux/seq_file.h>



#include "fbnic.h"



static struct dentry *fbnic_dbg_root;



static int fbnic_dbg_pcie_stats_show(struct seq_file *s, void *v)

{

	struct fbnic_dev *fbd = s->private;



	rtnl_lock();

	fbnic_get_hw_stats(fbd);



	seq_printf(s, "ob_rd_tlp: %llu\n", fbd->hw_stats.pcie.ob_rd_tlp.value);

	seq_printf(s, "ob_rd_dword: %llu\n",

		   fbd->hw_stats.pcie.ob_rd_dword.value);

	seq_printf(s, "ob_wr_tlp: %llu\n", fbd->hw_stats.pcie.ob_wr_tlp.value);

	seq_printf(s, "ob_wr_dword: %llu\n",

		   fbd->hw_stats.pcie.ob_wr_dword.value);

	seq_printf(s, "ob_cpl_tlp: %llu\n",

		   fbd->hw_stats.pcie.ob_cpl_tlp.value);

	seq_printf(s, "ob_cpl_dword: %llu\n",

		   fbd->hw_stats.pcie.ob_cpl_dword.value);

	seq_printf(s, "ob_rd_no_tag: %llu\n",

		   fbd->hw_stats.pcie.ob_rd_no_tag.value);

	seq_printf(s, "ob_rd_no_cpl_cred: %llu\n",

		   fbd->hw_stats.pcie.ob_rd_no_cpl_cred.value);

	seq_printf(s, "ob_rd_no_np_cred: %llu\n",

		   fbd->hw_stats.pcie.ob_rd_no_np_cred.value);

	rtnl_unlock();



	return 0;

}



DEFINE_SHOW_ATTRIBUTE(fbnic_dbg_pcie_stats);



void fbnic_dbg_fbd_init(struct fbnic_dev *fbd)

{

	struct pci_dev *pdev = to_pci_dev(fbd->dev);

	const char *name = pci_name(pdev);



	fbd->dbg_fbd = debugfs_create_dir(name, fbnic_dbg_root);

	debugfs_create_file("pcie_stats", 0400, fbd->dbg_fbd, fbd,

			    &fbnic_dbg_pcie_stats_fops);

}



void fbnic_dbg_fbd_exit(struct fbnic_dev *fbd)

drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c

+114 −0
Original line number Diff line number Diff line
@@ -28,3 +28,117 @@ u64 fbnic_stat_rd64(struct fbnic_dev *fbd, u32 reg, u32 offset) 
	 */

	return ((u64)upper << 32);

}



static void fbnic_hw_stat_rst64(struct fbnic_dev *fbd, u32 reg, s32 offset,

				struct fbnic_stat_counter *stat)

{

	/* Record initial counter values and compute deltas from there to ensure

	 * stats start at 0 after reboot/reset. This avoids exposing absolute

	 * hardware counter values to userspace.

	 */

	stat->u.old_reg_value_64 = fbnic_stat_rd64(fbd, reg, offset);

}



static void fbnic_hw_stat_rd64(struct fbnic_dev *fbd, u32 reg, s32 offset,

			       struct fbnic_stat_counter *stat)

{

	u64 new_reg_value;



	new_reg_value = fbnic_stat_rd64(fbd, reg, offset);

	stat->value += new_reg_value - stat->u.old_reg_value_64;

	stat->u.old_reg_value_64 = new_reg_value;

}



static void fbnic_reset_pcie_stats_asic(struct fbnic_dev *fbd,

					struct fbnic_pcie_stats *pcie)

{

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_RD_TLP_CNT_31_0,

			    1,

			    &pcie->ob_rd_tlp);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_RD_DWORD_CNT_31_0,

			    1,

			    &pcie->ob_rd_dword);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_CPL_TLP_CNT_31_0,

			    1,

			    &pcie->ob_cpl_tlp);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_CPL_DWORD_CNT_31_0,

			    1,

			    &pcie->ob_cpl_dword);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_WR_TLP_CNT_31_0,

			    1,

			    &pcie->ob_wr_tlp);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_WR_DWORD_CNT_31_0,

			    1,

			    &pcie->ob_wr_dword);



	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_RD_DBG_CNT_TAG_31_0,

			    1,

			    &pcie->ob_rd_no_tag);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_RD_DBG_CNT_CPL_CRED_31_0,

			    1,

			    &pcie->ob_rd_no_cpl_cred);

	fbnic_hw_stat_rst64(fbd,

			    FBNIC_PUL_USER_OB_RD_DBG_CNT_NP_CRED_31_0,

			    1,

			    &pcie->ob_rd_no_np_cred);

}



static void fbnic_get_pcie_stats_asic64(struct fbnic_dev *fbd,

					struct fbnic_pcie_stats *pcie)

{

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_RD_TLP_CNT_31_0,

			   1,

			   &pcie->ob_rd_tlp);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_RD_DWORD_CNT_31_0,

			   1,

			   &pcie->ob_rd_dword);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_WR_TLP_CNT_31_0,

			   1,

			   &pcie->ob_wr_tlp);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_WR_DWORD_CNT_31_0,

			   1,

			   &pcie->ob_wr_dword);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_CPL_TLP_CNT_31_0,

			   1,

			   &pcie->ob_cpl_tlp);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_CPL_DWORD_CNT_31_0,

			   1,

			   &pcie->ob_cpl_dword);



	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_RD_DBG_CNT_TAG_31_0,

			   1,

			   &pcie->ob_rd_no_tag);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_RD_DBG_CNT_CPL_CRED_31_0,

			   1,

			   &pcie->ob_rd_no_cpl_cred);

	fbnic_hw_stat_rd64(fbd,

			   FBNIC_PUL_USER_OB_RD_DBG_CNT_NP_CRED_31_0,

			   1,

			   &pcie->ob_rd_no_np_cred);

}



void fbnic_reset_hw_stats(struct fbnic_dev *fbd)

{

	fbnic_reset_pcie_stats_asic(fbd, &fbd->hw_stats.pcie);

}



void fbnic_get_hw_stats(struct fbnic_dev *fbd)

{

	fbnic_get_pcie_stats_asic64(fbd, &fbd->hw_stats.pcie);

}

drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h

+12 −0
Original line number Diff line number Diff line
@@ -37,12 +37,24 @@ struct fbnic_mac_stats { 
	struct fbnic_eth_mac_stats eth_mac;

};



struct fbnic_pcie_stats {

	struct fbnic_stat_counter ob_rd_tlp, ob_rd_dword;

	struct fbnic_stat_counter ob_wr_tlp, ob_wr_dword;

	struct fbnic_stat_counter ob_cpl_tlp, ob_cpl_dword;



	struct fbnic_stat_counter ob_rd_no_tag;

	struct fbnic_stat_counter ob_rd_no_cpl_cred;

	struct fbnic_stat_counter ob_rd_no_np_cred;

};



struct fbnic_hw_stats {

	struct fbnic_mac_stats mac;

	struct fbnic_pcie_stats pcie;

};



u64 fbnic_stat_rd64(struct fbnic_dev *fbd, u32 reg, u32 offset);



void fbnic_reset_hw_stats(struct fbnic_dev *fbd);

void fbnic_get_hw_stats(struct fbnic_dev *fbd);



#endif /* _FBNIC_HW_STATS_H_ */