diff mbox series

[net-next,4/5] eth: fbnic: add PCIe hardware statistics

Message ID 20241115015344.757567-5-kuba@kernel.org (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series eth: fbnic: cleanup and add a few stats | expand

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netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 6 maintainers not CCed: horms@kernel.org linux-doc@vger.kernel.org kernel-team@meta.com andrew+netdev@lunn.ch corbet@lwn.net mohsin.bashr@gmail.com
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 284 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jakub Kicinski Nov. 15, 2024, 1:53 a.m. UTC
From: Sanman Pradhan <sanman.p211993@gmail.com>

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: Sanman Pradhan <sanman.p211993@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 .../device_drivers/ethernet/meta/fbnic.rst    |  30 +++++
 drivers/net/ethernet/meta/fbnic/fbnic_csr.h   |  37 ++++++
 .../net/ethernet/meta/fbnic/fbnic_debugfs.c   |  34 ++++++
 .../net/ethernet/meta/fbnic/fbnic_hw_stats.c  | 114 ++++++++++++++++++
 .../net/ethernet/meta/fbnic/fbnic_hw_stats.h  |  12 ++
 drivers/net/ethernet/meta/fbnic/fbnic_pci.c   |   4 +
 6 files changed, 231 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst b/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
index 32ff114f5c26..14f2834d86d1 100644
--- a/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
+++ b/Documentation/networking/device_drivers/ethernet/meta/fbnic.rst
@@ -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
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_csr.h b/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
index f9a531ce9e17..dac9a4879e52 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
@@ -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
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c b/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
index 183c7c4914dc..59951b5abdb7 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
@@ -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)
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
index b3f8dc299b29..c391f2155054 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
@@ -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);
+}
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h
index 199ad2228ee9..b152c6b1b4ab 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h
@@ -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_ */
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
index 877c45e6dcae..0aa95160f006 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
@@ -9,6 +9,7 @@ 
 
 #include "fbnic.h"
 #include "fbnic_drvinfo.h"
+#include "fbnic_hw_stats.h"
 #include "fbnic_netdev.h"
 
 char fbnic_driver_name[] = DRV_NAME;
@@ -290,6 +291,9 @@  static int fbnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	fbnic_devlink_register(fbd);
 	fbnic_dbg_fbd_init(fbd);
 
+	/* Capture snapshot of hardware stats so netdev can calculate delta */
+	fbnic_reset_hw_stats(fbd);
+
 	fbnic_hwmon_register(fbd);
 
 	if (!fbd->dsn) {