Subject: [PATCH net-next 2/2] eth: fbnic: Add support to fetch group stats

From: Mohsin Bashir <[email-masked]>
Date: Thu, 22 Aug 2024 11:49:44 -0700

Add support for group stats for mac. The fbnic_set_counter help prevent
overriding the default values for counters which are not collected by the device.

The 'reset' flag in 'get_eth_mac_stats' allows to choose between
resetting the counter to recent most value or fecthing the aggregate
values of counters. This is important to cater for cases such as
device reset.

The 'fbnic_stat_rd64' read 64b stats counters in a consistent fashion using
high-low-high approach. This allows to isolate cases where counter is
wrapped between the reads.

Command: ethtool -S eth0 --groups eth-mac

Example Output:
eth-mac-FramesTransmittedOK: 158011
eth-mac-FramesReceivedOK: 1569970
eth-mac-FrameCheckSequenceErrors: 0
eth-mac-AlignmentErrors: 0
eth-mac-OctetsTransmittedOK: 17282419
eth-mac-FramesLostDueToIntMACXmitError: 0
eth-mac-OctetsReceivedOK: 2305095088
eth-mac-FramesLostDueToIntMACRcvError: 0
eth-mac-MulticastFramesXmittedOK: 118
eth-mac-BroadcastFramesXmittedOK: 18
eth-mac-MulticastFramesReceivedOK: 11583
eth-mac-BroadcastFramesReceivedOK: 1069
eth-mac-FrameTooLongErrors: 0

Signed-off-by: Mohsin Bashir <[email-masked]>
---
 drivers/net/ethernet/meta/fbnic/Makefile      |  1 +
 drivers/net/ethernet/meta/fbnic/fbnic.h       |  4 ++
 drivers/net/ethernet/meta/fbnic/fbnic_csr.h   | 37 ++++++++++++++
 .../net/ethernet/meta/fbnic/fbnic_ethtool.c   | 49 ++++++++++++++++++
 .../net/ethernet/meta/fbnic/fbnic_hw_stats.c  | 27 ++++++++++
 .../net/ethernet/meta/fbnic/fbnic_hw_stats.h  | 40 +++++++++++++++
 drivers/net/ethernet/meta/fbnic/fbnic_mac.c   | 50 +++++++++++++++++++
 drivers/net/ethernet/meta/fbnic/fbnic_mac.h   |  3 ++
 8 files changed, 211 insertions(+)
 create mode 100644 drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
 create mode 100644 drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h

diff --git a/drivers/net/ethernet/meta/fbnic/Makefile b/drivers/net/ethernet/meta/fbnic/Makefile
index 37cfc34a5118..ed4533a73c57 100644
--- a/drivers/net/ethernet/meta/fbnic/Makefile
+++ b/drivers/net/ethernet/meta/fbnic/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_FBNIC) += fbnic.o
 fbnic-y := fbnic_devlink.o \
 	   fbnic_ethtool.o \
 	   fbnic_fw.o \
+	   fbnic_hw_stats.o \
 	   fbnic_irq.o \
 	   fbnic_mac.o \
 	   fbnic_netdev.o \
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic.h b/drivers/net/ethernet/meta/fbnic/fbnic.h
index 28d970f81bfc..0f9e8d79461c 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic.h
@@ -11,6 +11,7 @@
 
 #include "fbnic_csr.h"
 #include "fbnic_fw.h"
+#include "fbnic_hw_stats.h"
 #include "fbnic_mac.h"
 #include "fbnic_rpc.h"
 
@@ -47,6 +48,9 @@ struct fbnic_dev {
 
 	/* Number of TCQs/RCQs available on hardware */
 	u16 max_num_queues;
+
+	/* Local copy of hardware statistics */
+	struct fbnic_hw_stats hw_stats;
 };
 
 /* Reserve entry 0 in the MSI-X "others" array until we have filled all
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_csr.h b/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
index a64360de0552..21db509acbc1 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
@@ -660,6 +660,43 @@ enum {
 #define FBNIC_SIG_PCS_INTR_MASK		0x11816		/* 0x46058 */
 #define FBNIC_CSR_END_SIG		0x1184e /* CSR section delimiter */
 
+#define FBNIC_CSR_START_MAC_STAT	0x11a00
+#define FBNIC_MAC_STAT_RX_BYTE_COUNT_L	0x11a08		/* 0x46820 */
+#define FBNIC_MAC_STAT_RX_BYTE_COUNT_H	0x11a09		/* 0x46824 */
+#define FBNIC_MAC_STAT_RX_ALIGN_ERROR_L \
+					0x11a0a		/* 0x46828 */
+#define FBNIC_MAC_STAT_RX_ALIGN_ERROR_H \
+					0x11a0b		/* 0x4682c */
+#define FBNIC_MAC_STAT_RX_TOOLONG_L	0x11a0e		/* 0x46838 */
+#define FBNIC_MAC_STAT_RX_TOOLONG_H	0x11a0f		/* 0x4683c */
+#define FBNIC_MAC_STAT_RX_RECEIVED_OK_L	\
+					0x11a12		/* 0x46848 */
+#define FBNIC_MAC_STAT_RX_RECEIVED_OK_H	\
+					0x11a13		/* 0x4684c */
+#define FBNIC_MAC_STAT_RX_PACKET_BAD_FCS_L \
+					0x11a14		/* 0x46850 */
+#define FBNIC_MAC_STAT_RX_PACKET_BAD_FCS_H \
+					0x11a15		/* 0x46854 */
+#define FBNIC_MAC_STAT_RX_IFINERRORS_L	0x11a18		/* 0x46860 */
+#define FBNIC_MAC_STAT_RX_IFINERRORS_H	0x11a19		/* 0x46864 */
+#define FBNIC_MAC_STAT_RX_MULTICAST_L	0x11a1c		/* 0x46870 */
+#define FBNIC_MAC_STAT_RX_MULTICAST_H	0x11a1d		/* 0x46874 */
+#define FBNIC_MAC_STAT_RX_BROADCAST_L	0x11a1e		/* 0x46878 */
+#define FBNIC_MAC_STAT_RX_BROADCAST_H	0x11a1f		/* 0x4687c */
+#define FBNIC_MAC_STAT_TX_BYTE_COUNT_L	0x11a3e		/* 0x468f8 */
+#define FBNIC_MAC_STAT_TX_BYTE_COUNT_H	0x11a3f		/* 0x468fc */
+#define FBNIC_MAC_STAT_TX_TRANSMITTED_OK_L \
+					0x11a42		/* 0x46908 */
+#define FBNIC_MAC_STAT_TX_TRANSMITTED_OK_H \
+					0x11a43		/* 0x4690c */
+#define FBNIC_MAC_STAT_TX_IFOUTERRORS_L \
+					0x11a46		/* 0x46918 */
+#define FBNIC_MAC_STAT_TX_IFOUTERRORS_H \
+					0x11a47		/* 0x4691c */
+#define FBNIC_MAC_STAT_TX_MULTICAST_L	0x11a4a		/* 0x46928 */
+#define FBNIC_MAC_STAT_TX_MULTICAST_H	0x11a4b		/* 0x4692c */
+#define FBNIC_MAC_STAT_TX_BROADCAST_L	0x11a4c		/* 0x46930 */
+#define FBNIC_MAC_STAT_TX_BROADCAST_H	0x11a4d		/* 0x46934 */
 /* PUL User Registers */
 #define FBNIC_CSR_START_PUL_USER	0x31000	/* CSR section delimiter */
 #define FBNIC_PUL_OB_TLP_HDR_AW_CFG	0x3103d		/* 0xc40f4 */
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
index 0dc083fd1878..c0cde0e8a7d7 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
@@ -16,8 +16,57 @@ fbnic_get_drvinfo(struct net_device *netdev, struct ethtool_drvinfo *drvinfo)
 				    sizeof(drvinfo->fw_version));
 }
 
+static void fbnic_set_counter(u64 *stat, struct fbnic_stat_counter *counter)
+{
+	if (counter->reported)
+		*stat = counter->value;
+}
+
+static void
+fbnic_get_eth_mac_stats(struct net_device *netdev,
+			struct ethtool_eth_mac_stats *eth_mac_stats)
+{
+	struct fbnic_net *fbn = netdev_priv(netdev);
+	struct fbnic_mac_stats *mac_stats;
+	struct fbnic_dev *fbd = fbn->fbd;
+	const struct fbnic_mac *mac;
+
+	mac_stats = &fbd->hw_stats.mac;
+	mac = fbd->mac;
+
+	mac->get_eth_mac_stats(fbd, false, &mac_stats->eth_mac);
+
+	fbnic_set_counter(&eth_mac_stats->FramesTransmittedOK,
+			  &mac_stats->eth_mac.FramesTransmittedOK);
+	fbnic_set_counter(&eth_mac_stats->FramesReceivedOK,
+			  &mac_stats->eth_mac.FramesReceivedOK);
+	fbnic_set_counter(&eth_mac_stats->FrameCheckSequenceErrors,
+			  &mac_stats->eth_mac.FrameCheckSequenceErrors);
+	fbnic_set_counter(&eth_mac_stats->AlignmentErrors,
+			  &mac_stats->eth_mac.AlignmentErrors);
+	fbnic_set_counter(&eth_mac_stats->OctetsTransmittedOK,
+			  &mac_stats->eth_mac.OctetsTransmittedOK);
+	fbnic_set_counter(&eth_mac_stats->FramesLostDueToIntMACXmitError,
+			  &mac_stats->eth_mac.FramesLostDueToIntMACXmitError);
+	fbnic_set_counter(&eth_mac_stats->OctetsReceivedOK,
+			  &mac_stats->eth_mac.OctetsReceivedOK);
+	fbnic_set_counter(&eth_mac_stats->FramesLostDueToIntMACRcvError,
+			  &mac_stats->eth_mac.FramesLostDueToIntMACRcvError);
+	fbnic_set_counter(&eth_mac_stats->MulticastFramesXmittedOK,
+			  &mac_stats->eth_mac.MulticastFramesXmittedOK);
+	fbnic_set_counter(&eth_mac_stats->BroadcastFramesXmittedOK,
+			  &mac_stats->eth_mac.BroadcastFramesXmittedOK);
+	fbnic_set_counter(&eth_mac_stats->MulticastFramesReceivedOK,
+			  &mac_stats->eth_mac.MulticastFramesReceivedOK);
+	fbnic_set_counter(&eth_mac_stats->BroadcastFramesReceivedOK,
+			  &mac_stats->eth_mac.BroadcastFramesReceivedOK);
+	fbnic_set_counter(&eth_mac_stats->FrameTooLongErrors,
+			  &mac_stats->eth_mac.FrameTooLongErrors);
+}
+
 static const struct ethtool_ops fbnic_ethtool_ops = {
 	.get_drvinfo		= fbnic_get_drvinfo,
+	.get_eth_mac_stats	= fbnic_get_eth_mac_stats,
 };
 
 void fbnic_set_ethtool_ops(struct net_device *dev)
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
new file mode 100644
index 000000000000..a0acc7606aa1
--- /dev/null
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
@@ -0,0 +1,27 @@
+#include "fbnic.h"
+
+u64 fbnic_stat_rd64(struct fbnic_dev *fbd, u32 reg, u32 offset)
+{
+	u32 prev_upper, upper, lower, diff;
+
+	prev_upper = rd32(fbd, reg + offset);
+	lower = rd32(fbd, reg);
+	upper = rd32(fbd, reg + offset);
+
+	diff = upper - prev_upper;
+	if (!diff)
+		return ((u64)upper << 32) | lower;
+
+	if (diff > 1)
+		dev_warn_once(fbd->dev,
+			      "Stats inconsistent, upper 32b of %#010x updating too quickly\n",
+			      reg * 4);
+
+	/* Return only the upper bits as we cannot guarantee
+	 * the accuracy of the lower bits. We will add them in
+	 * when the counter slows down enough that we can get
+	 * a snapshot with both upper values being the same
+	 * between reads.
+	 */
+	return ((u64)upper << 32);
+}
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h
new file mode 100644
index 000000000000..30348904b510
--- /dev/null
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.h
@@ -0,0 +1,40 @@
+#include <linux/ethtool.h>
+
+#include "fbnic_csr.h"
+
+struct fbnic_stat_counter {
+	u64 value;
+	union {
+		u32 old_reg_value_32;
+		u64 old_reg_value_64;
+	} u;
+	bool reported;
+};
+
+struct fbnic_eth_mac_stats {
+	struct fbnic_stat_counter FramesTransmittedOK;
+	struct fbnic_stat_counter FramesReceivedOK;
+	struct fbnic_stat_counter FrameCheckSequenceErrors;
+	struct fbnic_stat_counter AlignmentErrors;
+	struct fbnic_stat_counter OctetsTransmittedOK;
+	struct fbnic_stat_counter FramesLostDueToIntMACXmitError;
+	struct fbnic_stat_counter OctetsReceivedOK;
+	struct fbnic_stat_counter FramesLostDueToIntMACRcvError;
+	struct fbnic_stat_counter MulticastFramesXmittedOK;
+	struct fbnic_stat_counter BroadcastFramesXmittedOK;
+	struct fbnic_stat_counter MulticastFramesReceivedOK;
+	struct fbnic_stat_counter BroadcastFramesReceivedOK;
+	struct fbnic_stat_counter FrameTooLongErrors;
+};
+
+struct fbnic_mac_stats {
+	struct fbnic_eth_mac_stats eth_mac;
+};
+
+struct fbnic_hw_stats {
+	struct fbnic_mac_stats mac;
+};
+
+u64 fbnic_stat_rd64(struct fbnic_dev *fbd, u32 reg, u32 offset);
+
+void fbnic_get_hw_stats(struct fbnic_dev *fbd);
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_mac.c b/drivers/net/ethernet/meta/fbnic/fbnic_mac.c
index 7920e7af82d9..7b654d0a6dac 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_mac.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_mac.c
@@ -403,6 +403,21 @@ static void fbnic_mac_init_regs(struct fbnic_dev *fbd)
 	fbnic_mac_init_txb(fbd);
 }
 
+static void __fbnic_mac_stat_rd64(struct fbnic_dev *fbd, bool reset, u32 reg,
+				  struct fbnic_stat_counter *stat)
+{
+	u64 new_reg_value;
+
+	new_reg_value = fbnic_stat_rd64(fbd, reg, 1);
+	if (!reset)
+		stat->value += new_reg_value - stat->u.old_reg_value_64;
+	stat->u.old_reg_value_64 = new_reg_value;
+	stat->reported = true;
+}
+
+#define fbnic_mac_stat_rd64(fbd, reset, __stat, __CSR) \
+	__fbnic_mac_stat_rd64(fbd, reset, FBNIC_##__CSR##_L, &(__stat))
+
 static void fbnic_mac_tx_pause_config(struct fbnic_dev *fbd, bool tx_pause)
 {
 	u32 rxb_pause_ctrl;
@@ -637,12 +652,47 @@ static void fbnic_mac_link_up_asic(struct fbnic_dev *fbd,
 	wr32(fbd, FBNIC_MAC_COMMAND_CONFIG, cmd_cfg);
 }
 
+static void
+fbnic_mac_get_eth_mac_stats(struct fbnic_dev *fbd, bool reset,
+			    struct fbnic_eth_mac_stats *mac_stats)
+{
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->OctetsReceivedOK,
+			    MAC_STAT_RX_BYTE_COUNT);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->AlignmentErrors,
+			    MAC_STAT_RX_ALIGN_ERROR);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->FrameTooLongErrors,
+			    MAC_STAT_RX_TOOLONG);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->FramesReceivedOK,
+			    MAC_STAT_RX_RECEIVED_OK);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->FrameCheckSequenceErrors,
+			    MAC_STAT_RX_PACKET_BAD_FCS);
+	fbnic_mac_stat_rd64(fbd, reset,
+			    mac_stats->FramesLostDueToIntMACRcvError,
+			    MAC_STAT_RX_IFINERRORS);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->MulticastFramesReceivedOK,
+			    MAC_STAT_RX_MULTICAST);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->BroadcastFramesReceivedOK,
+			    MAC_STAT_RX_BROADCAST);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->OctetsTransmittedOK,
+			    MAC_STAT_TX_BYTE_COUNT);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->FramesTransmittedOK,
+			    MAC_STAT_TX_TRANSMITTED_OK);
+	fbnic_mac_stat_rd64(fbd, reset,
+			    mac_stats->FramesLostDueToIntMACXmitError,
+			    MAC_STAT_TX_IFOUTERRORS);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->MulticastFramesXmittedOK,
+			    MAC_STAT_TX_MULTICAST);
+	fbnic_mac_stat_rd64(fbd, reset, mac_stats->BroadcastFramesXmittedOK,
+			    MAC_STAT_TX_BROADCAST);
+}
+
 static const struct fbnic_mac fbnic_mac_asic = {
 	.init_regs = fbnic_mac_init_regs,
 	.pcs_enable = fbnic_pcs_enable_asic,
 	.pcs_disable = fbnic_pcs_disable_asic,
 	.pcs_get_link = fbnic_pcs_get_link_asic,
 	.pcs_get_link_event = fbnic_pcs_get_link_event_asic,
+	.get_eth_mac_stats = fbnic_mac_get_eth_mac_stats,
 	.link_down = fbnic_mac_link_down_asic,
 	.link_up = fbnic_mac_link_up_asic,
 };
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_mac.h b/drivers/net/ethernet/meta/fbnic/fbnic_mac.h
index f53be6e6aef9..476239a9d381 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_mac.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_mac.h
@@ -78,6 +78,9 @@ struct fbnic_mac {
 	bool (*pcs_get_link)(struct fbnic_dev *fbd);
 	int (*pcs_get_link_event)(struct fbnic_dev *fbd);
 
+	void (*get_eth_mac_stats)(struct fbnic_dev *fbd, bool reset,
+				  struct fbnic_eth_mac_stats *mac_stats);
+
 	void (*link_down)(struct fbnic_dev *fbd);
 	void (*link_up)(struct fbnic_dev *fbd, bool tx_pause, bool rx_pause);
 };
-- 
2.43.5