Merge branch 'eth-fbnic-add-firmware-logging-support'

Lee Trager says:

====================
eth: fbnic: Add firmware logging support

Firmware running on fbnic generates device logs. These logs contain useful
information about the device which may or may not be related to the host.
Logs are stored in a ring buffer and accessible through DebugFS.
====================

Link: https://patch.msgid.link/20250702192207.697368-1-lee@trager.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

9 files changed, 451 insertions, 13 deletions

diff --git a/drivers/net/ethernet/meta/fbnic/Makefile b/drivers/net/ethernet/meta/fbnic/Makefile
index 0dbc634adb4b..15e8ff649615 100644
--- a/drivers/net/ethernet/meta/fbnic/Makefile
+++ b/drivers/net/ethernet/meta/fbnic/Makefile
@@ -12,6 +12,7 @@ fbnic-y := fbnic_csr.o \
 	   fbnic_devlink.o \
 	   fbnic_ethtool.o \
 	   fbnic_fw.o \
+	   fbnic_fw_log.o \
 	   fbnic_hw_stats.o \
 	   fbnic_hwmon.o \
 	   fbnic_irq.o \
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic.h b/drivers/net/ethernet/meta/fbnic/fbnic.h
index 65815d4f379e..c376e06880c9 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic.h
@@ -12,6 +12,7 @@
 
 #include "fbnic_csr.h"
 #include "fbnic_fw.h"
+#include "fbnic_fw_log.h"
 #include "fbnic_hw_stats.h"
 #include "fbnic_mac.h"
 #include "fbnic_rpc.h"
@@ -85,6 +86,8 @@ struct fbnic_dev {
 
 	/* Lock protecting access to hw_stats */
 	spinlock_t hw_stats_lock;
+
+	struct fbnic_fw_log fw_log;
 };
 
 /* 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 9c89d5378668..a81db842aa53 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_csr.h
@@ -12,13 +12,28 @@
 #define DESC_BIT(nr)		BIT_ULL(nr)
 #define DESC_GENMASK(h, l)	GENMASK_ULL(h, l)
 
+#define FW_VER_CODE(_major, _minor, _patch, _build) (		      \
+		FIELD_PREP(FBNIC_FW_CAP_RESP_VERSION_MAJOR, _major) | \
+		FIELD_PREP(FBNIC_FW_CAP_RESP_VERSION_MINOR, _minor) | \
+		FIELD_PREP(FBNIC_FW_CAP_RESP_VERSION_PATCH, _patch) | \
+		FIELD_PREP(FBNIC_FW_CAP_RESP_VERSION_BUILD, _build))
+
 /* Defines the minimum firmware version required by the driver */
-#define MIN_FW_MAJOR_VERSION    0
-#define MIN_FW_MINOR_VERSION    10
-#define MIN_FW_BUILD_VERSION    6
-#define MIN_FW_VERSION_CODE     (MIN_FW_MAJOR_VERSION * (1u << 24) + \
-				 MIN_FW_MINOR_VERSION * (1u << 16) + \
-				 MIN_FW_BUILD_VERSION)
+#define MIN_FW_VER_CODE				FW_VER_CODE(0, 10, 6, 0)
+
+/* Defines the minimum firmware version required for firmware logs */
+#define MIN_FW_VER_CODE_LOG			FW_VER_CODE(0, 12, 9, 0)
+
+/* Driver can request that firmware sends all cached logs in bulk. This
+ * feature was enabled on older firmware however firmware has a bug
+ * which attempted to send 30 messages per mbx message which caused an
+ * overflow flooding the mailbox. This results in a kernel warning
+ * related to corrupt mailbox messages.
+ *
+ * If firmware is new enough only request sending historical logs when
+ * the log buffer is empty to prevent duplicate logs.
+ */
+#define MIN_FW_VER_CODE_HIST			FW_VER_CODE(25, 5, 7, 0)
 
 #define PCI_DEVICE_ID_META_FBNIC_ASIC		0x0013
 
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c b/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
index e8f2d7f2d962..b7238dd967fe 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_debugfs.c
@@ -170,6 +170,33 @@ static int fbnic_dbg_ipo_dst_show(struct seq_file *s, void *v)
 }
 DEFINE_SHOW_ATTRIBUTE(fbnic_dbg_ipo_dst);
 
+static int fbnic_dbg_fw_log_show(struct seq_file *s, void *v)
+{
+	struct fbnic_dev *fbd = s->private;
+	struct fbnic_fw_log_entry *entry;
+	unsigned long flags;
+
+	if (!fbnic_fw_log_ready(fbd))
+		return -ENXIO;
+
+	spin_lock_irqsave(&fbd->fw_log.lock, flags);
+
+	list_for_each_entry_reverse(entry, &fbd->fw_log.entries, list) {
+		seq_printf(s, FBNIC_FW_LOG_FMT, entry->index,
+			   (entry->timestamp / (MSEC_PER_SEC * 60 * 60 * 24)),
+			   (entry->timestamp / (MSEC_PER_SEC * 60 * 60)) % 24,
+			   ((entry->timestamp / (MSEC_PER_SEC * 60) % 60)),
+			   ((entry->timestamp / MSEC_PER_SEC) % 60),
+			   (entry->timestamp % MSEC_PER_SEC),
+			   entry->msg);
+	}
+
+	spin_unlock_irqrestore(&fbd->fw_log.lock, flags);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(fbnic_dbg_fw_log);
+
 static int fbnic_dbg_pcie_stats_show(struct seq_file *s, void *v)
 {
 	struct fbnic_dev *fbd = s->private;
@@ -222,6 +249,8 @@ void fbnic_dbg_fbd_init(struct fbnic_dev *fbd)
 			    &fbnic_dbg_ipo_src_fops);
 	debugfs_create_file("ipo_dst", 0400, fbd->dbg_fbd, fbd,
 			    &fbnic_dbg_ipo_dst_fops);
+	debugfs_create_file("fw_log", 0400, fbd->dbg_fbd, fbd,
+			    &fbnic_dbg_fw_log_fops);
 }
 
 void fbnic_dbg_fbd_exit(struct fbnic_dev *fbd)
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw.c b/drivers/net/ethernet/meta/fbnic/fbnic_fw.c
index 1d220d8369e7..0c55be7d2547 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_fw.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw.c
@@ -573,16 +573,15 @@ static int fbnic_fw_parse_cap_resp(void *opaque, struct fbnic_tlv_msg **results)
 	if (!fbd->fw_cap.running.mgmt.version)
 		return -EINVAL;
 
-	if (fbd->fw_cap.running.mgmt.version < MIN_FW_VERSION_CODE) {
+	if (fbd->fw_cap.running.mgmt.version < MIN_FW_VER_CODE) {
+		char required_ver[FBNIC_FW_VER_MAX_SIZE];
 		char running_ver[FBNIC_FW_VER_MAX_SIZE];
 
 		fbnic_mk_fw_ver_str(fbd->fw_cap.running.mgmt.version,
 				    running_ver);
-		dev_err(fbd->dev, "Device firmware version(%s) is older than minimum required version(%02d.%02d.%02d)\n",
-			running_ver,
-			MIN_FW_MAJOR_VERSION,
-			MIN_FW_MINOR_VERSION,
-			MIN_FW_BUILD_VERSION);
+		fbnic_mk_fw_ver_str(MIN_FW_VER_CODE, required_ver);
+		dev_err(fbd->dev, "Device firmware version(%s) is older than minimum required version(%s)\n",
+			running_ver, required_ver);
 		/* Disable TX mailbox to prevent card use until firmware is
 		 * updated.
 		 */
@@ -1035,6 +1034,169 @@ msg_err:
 	return err;
 }
 
+static const struct fbnic_tlv_index fbnic_fw_log_req_index[] = {
+	FBNIC_TLV_ATTR_U32(FBNIC_FW_LOG_MSEC),
+	FBNIC_TLV_ATTR_U64(FBNIC_FW_LOG_INDEX),
+	FBNIC_TLV_ATTR_STRING(FBNIC_FW_LOG_MSG, FBNIC_FW_LOG_MAX_SIZE),
+	FBNIC_TLV_ATTR_U32(FBNIC_FW_LOG_LENGTH),
+	FBNIC_TLV_ATTR_ARRAY(FBNIC_FW_LOG_MSEC_ARRAY),
+	FBNIC_TLV_ATTR_ARRAY(FBNIC_FW_LOG_INDEX_ARRAY),
+	FBNIC_TLV_ATTR_ARRAY(FBNIC_FW_LOG_MSG_ARRAY),
+	FBNIC_TLV_ATTR_LAST
+};
+
+static int fbnic_fw_process_log_array(struct fbnic_tlv_msg **results,
+				      u16 length, u16 arr_type_idx,
+				      u16 attr_type_idx,
+				      struct fbnic_tlv_msg **tlv_array_out)
+{
+	struct fbnic_tlv_msg *attr;
+	int attr_len;
+	int err;
+
+	if (!results[attr_type_idx])
+		return -EINVAL;
+
+	tlv_array_out[0] = results[attr_type_idx];
+
+	if (!length)
+		return 0;
+
+	if (!results[arr_type_idx])
+		return -EINVAL;
+
+	attr = results[arr_type_idx];
+	attr_len = le16_to_cpu(attr->hdr.len) / sizeof(u32) - 1;
+	err = fbnic_tlv_attr_parse_array(&attr[1], attr_len, &tlv_array_out[1],
+					 fbnic_fw_log_req_index,
+					 attr_type_idx,
+					 length);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int fbnic_fw_parse_logs(struct fbnic_dev *fbd,
+			       struct fbnic_tlv_msg **msec_tlv,
+			       struct fbnic_tlv_msg **index_tlv,
+			       struct fbnic_tlv_msg **log_tlv,
+			       int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		char log[FBNIC_FW_LOG_MAX_SIZE];
+		ssize_t len;
+		u64 index;
+		u32 msec;
+		int err;
+
+		if (!msec_tlv[i] || !index_tlv[i] || !log_tlv[i]) {
+			dev_warn(fbd->dev, "Received log message with missing attributes!\n");
+			return -EINVAL;
+		}
+
+		index = fbnic_tlv_attr_get_signed(index_tlv[i], 0);
+		msec = fbnic_tlv_attr_get_signed(msec_tlv[i], 0);
+		len = fbnic_tlv_attr_get_string(log_tlv[i], log,
+						FBNIC_FW_LOG_MAX_SIZE);
+		if (len < 0)
+			return len;
+
+		err = fbnic_fw_log_write(fbd, index, msec, log);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int fbnic_fw_parse_log_req(void *opaque,
+				  struct fbnic_tlv_msg **results)
+{
+	struct fbnic_tlv_msg *index_tlv[FBNIC_FW_MAX_LOG_HISTORY];
+	struct fbnic_tlv_msg *msec_tlv[FBNIC_FW_MAX_LOG_HISTORY];
+	struct fbnic_tlv_msg *log_tlv[FBNIC_FW_MAX_LOG_HISTORY];
+	struct fbnic_dev *fbd = opaque;
+	u16 length;
+	int err;
+
+	length = fta_get_uint(results, FBNIC_FW_LOG_LENGTH);
+	if (length >= FBNIC_FW_MAX_LOG_HISTORY)
+		return -E2BIG;
+
+	err = fbnic_fw_process_log_array(results, length,
+					 FBNIC_FW_LOG_MSEC_ARRAY,
+					 FBNIC_FW_LOG_MSEC, msec_tlv);
+	if (err)
+		return err;
+
+	err = fbnic_fw_process_log_array(results, length,
+					 FBNIC_FW_LOG_INDEX_ARRAY,
+					 FBNIC_FW_LOG_INDEX, index_tlv);
+	if (err)
+		return err;
+
+	err = fbnic_fw_process_log_array(results, length,
+					 FBNIC_FW_LOG_MSG_ARRAY,
+					 FBNIC_FW_LOG_MSG, log_tlv);
+	if (err)
+		return err;
+
+	err = fbnic_fw_parse_logs(fbd, msec_tlv, index_tlv, log_tlv,
+				  length + 1);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+int fbnic_fw_xmit_send_logs(struct fbnic_dev *fbd, bool enable,
+			    bool send_log_history)
+{
+	struct fbnic_tlv_msg *msg;
+	int err;
+
+	if (fbd->fw_cap.running.mgmt.version < MIN_FW_VER_CODE_LOG) {
+		dev_warn(fbd->dev, "Firmware version is too old to support firmware logs!\n");
+		return -EOPNOTSUPP;
+	}
+
+	msg = fbnic_tlv_msg_alloc(FBNIC_TLV_MSG_ID_LOG_SEND_LOGS_REQ);
+	if (!msg)
+		return -ENOMEM;
+
+	if (enable) {
+		err = fbnic_tlv_attr_put_flag(msg, FBNIC_SEND_LOGS);
+		if (err)
+			goto free_message;
+
+		/* Report request for version 1 of logs */
+		err = fbnic_tlv_attr_put_int(msg, FBNIC_SEND_LOGS_VERSION,
+					     FBNIC_FW_LOG_VERSION);
+		if (err)
+			goto free_message;
+
+		if (send_log_history) {
+			err = fbnic_tlv_attr_put_flag(msg,
+						      FBNIC_SEND_LOGS_HISTORY);
+			if (err)
+				goto free_message;
+		}
+	}
+
+	err = fbnic_mbx_map_tlv_msg(fbd, msg);
+	if (err)
+		goto free_message;
+
+	return 0;
+
+free_message:
+	free_page((unsigned long)msg);
+	return err;
+}
+
 static const struct fbnic_tlv_parser fbnic_fw_tlv_parser[] = {
 	FBNIC_TLV_PARSER(FW_CAP_RESP, fbnic_fw_cap_resp_index,
 			 fbnic_fw_parse_cap_resp),
@@ -1054,6 +1216,9 @@ static const struct fbnic_tlv_parser fbnic_fw_tlv_parser[] = {
 	FBNIC_TLV_PARSER(TSENE_READ_RESP,
 			 fbnic_tsene_read_resp_index,
 			 fbnic_fw_parse_tsene_read_resp),
+	FBNIC_TLV_PARSER(LOG_MSG_REQ,
+			 fbnic_fw_log_req_index,
+			 fbnic_fw_parse_log_req),
 	FBNIC_TLV_MSG_ERROR
 };
 
@@ -1167,7 +1332,7 @@ int fbnic_mbx_poll_tx_ready(struct fbnic_dev *fbd)
 	 * to indicate we entered the polling state waiting for a response
 	 */
 	for (fbd->fw_cap.running.mgmt.version = 1;
-	     fbd->fw_cap.running.mgmt.version < MIN_FW_VERSION_CODE;) {
+	     fbd->fw_cap.running.mgmt.version < MIN_FW_VER_CODE;) {
 		if (!tx_mbx->ready)
 			err = -ENODEV;
 		if (err)
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw.h b/drivers/net/ethernet/meta/fbnic/fbnic_fw.h
index 555b231b38c1..fde331696fdd 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_fw.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw.h
@@ -22,7 +22,20 @@ struct fbnic_fw_mbx {
 #define FBNIC_FW_VER_MAX_SIZE			32
 // Formatted version is in the format XX.YY.ZZ_RRR_COMMIT
 #define FBNIC_FW_CAP_RESP_COMMIT_MAX_SIZE	(FBNIC_FW_VER_MAX_SIZE - 13)
+#define FBNIC_FW_LOG_VERSION			1
 #define FBNIC_FW_LOG_MAX_SIZE			256
+/*
+ * The max amount of logs which can fit in a single mailbox message. Firmware
+ * assumes each mailbox message is 4096B. The amount of messages supported is
+ * calculated as 4096 minus headers for message, arrays, and length minus the
+ * size of length divided by headers for each array plus the maximum LOG size,
+ * and the size of MSEC and INDEX. Put another way:
+ *
+ * MAX_LOG_HISTORY = ((4096 - TLV_HDR_SZ * 5 - LENGTH_SZ)
+ *                    / (FBNIC_FW_LOG_MAX_SIZE + TLV_HDR_SZ * 3 + MSEC_SZ
+ *                       + INDEX_SZ))
+ */
+#define FBNIC_FW_MAX_LOG_HISTORY		14
 
 struct fbnic_fw_ver {
 	u32 version;
@@ -82,6 +95,8 @@ int fbnic_fw_xmit_fw_write_chunk(struct fbnic_dev *fbd,
 				 int cancel_error);
 int fbnic_fw_xmit_tsene_read_msg(struct fbnic_dev *fbd,
 				 struct fbnic_fw_completion *cmpl_data);
+int fbnic_fw_xmit_send_logs(struct fbnic_dev *fbd, bool enable,
+			    bool send_log_history);
 struct fbnic_fw_completion *fbnic_fw_alloc_cmpl(u32 msg_type);
 void fbnic_fw_put_cmpl(struct fbnic_fw_completion *cmpl_data);
 
@@ -125,6 +140,9 @@ enum {
 	FBNIC_TLV_MSG_ID_FW_FINISH_UPGRADE_RESP		= 0x29,
 	FBNIC_TLV_MSG_ID_TSENE_READ_REQ			= 0x3C,
 	FBNIC_TLV_MSG_ID_TSENE_READ_RESP		= 0x3D,
+	FBNIC_TLV_MSG_ID_LOG_SEND_LOGS_REQ		= 0x43,
+	FBNIC_TLV_MSG_ID_LOG_MSG_REQ			= 0x44,
+	FBNIC_TLV_MSG_ID_LOG_MSG_RESP			= 0x45,
 };
 
 #define FBNIC_FW_CAP_RESP_VERSION_MAJOR		CSR_GENMASK(31, 24)
@@ -199,4 +217,22 @@ enum {
 	FBNIC_FW_FINISH_UPGRADE_MSG_MAX
 };
 
+enum {
+	FBNIC_SEND_LOGS				= 0x0,
+	FBNIC_SEND_LOGS_VERSION			= 0x1,
+	FBNIC_SEND_LOGS_HISTORY			= 0x2,
+	FBNIC_SEND_LOGS_MSG_MAX
+};
+
+enum {
+	FBNIC_FW_LOG_MSEC			= 0x0,
+	FBNIC_FW_LOG_INDEX			= 0x1,
+	FBNIC_FW_LOG_MSG			= 0x2,
+	FBNIC_FW_LOG_LENGTH			= 0x3,
+	FBNIC_FW_LOG_MSEC_ARRAY			= 0x4,
+	FBNIC_FW_LOG_INDEX_ARRAY		= 0x5,
+	FBNIC_FW_LOG_MSG_ARRAY			= 0x6,
+	FBNIC_FW_LOG_MSG_MAX
+};
+
 #endif /* _FBNIC_FW_H_ */
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c
new file mode 100644
index 000000000000..38749d47cee6
--- /dev/null
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) Meta Platforms, Inc. and affiliates. */
+
+#include <linux/spinlock.h>
+#include <linux/vmalloc.h>
+
+#include "fbnic.h"
+#include "fbnic_fw.h"
+#include "fbnic_fw_log.h"
+
+void fbnic_fw_log_enable(struct fbnic_dev *fbd, bool send_hist)
+{
+	int err;
+
+	if (!fbnic_fw_log_ready(fbd))
+		return;
+
+	if (fbd->fw_cap.running.mgmt.version < MIN_FW_VER_CODE_HIST)
+		send_hist = false;
+
+	err = fbnic_fw_xmit_send_logs(fbd, true, send_hist);
+	if (err && err != -EOPNOTSUPP)
+		dev_warn(fbd->dev, "Unable to enable firmware logs: %d\n", err);
+}
+
+void fbnic_fw_log_disable(struct fbnic_dev *fbd)
+{
+	int err;
+
+	err = fbnic_fw_xmit_send_logs(fbd, false, false);
+	if (err && err != -EOPNOTSUPP)
+		dev_warn(fbd->dev, "Unable to disable firmware logs: %d\n",
+			 err);
+}
+
+int fbnic_fw_log_init(struct fbnic_dev *fbd)
+{
+	struct fbnic_fw_log *log = &fbd->fw_log;
+	void *data;
+
+	if (WARN_ON_ONCE(fbnic_fw_log_ready(fbd)))
+		return -EEXIST;
+
+	data = vmalloc(FBNIC_FW_LOG_SIZE);
+	if (!data)
+		return -ENOMEM;
+
+	spin_lock_init(&fbd->fw_log.lock);
+	INIT_LIST_HEAD(&log->entries);
+	log->size = FBNIC_FW_LOG_SIZE;
+	log->data_start = data;
+	log->data_end = data + FBNIC_FW_LOG_SIZE;
+
+	fbnic_fw_log_enable(fbd, true);
+
+	return 0;
+}
+
+void fbnic_fw_log_free(struct fbnic_dev *fbd)
+{
+	struct fbnic_fw_log *log = &fbd->fw_log;
+
+	if (!fbnic_fw_log_ready(fbd))
+		return;
+
+	fbnic_fw_log_disable(fbd);
+	INIT_LIST_HEAD(&log->entries);
+	log->size = 0;
+	vfree(log->data_start);
+	log->data_start = NULL;
+	log->data_end = NULL;
+}
+
+int fbnic_fw_log_write(struct fbnic_dev *fbd, u64 index, u32 timestamp,
+		       char *msg)
+{
+	struct fbnic_fw_log_entry *entry, *head, *tail, *next;
+	struct fbnic_fw_log *log = &fbd->fw_log;
+	size_t msg_len = strlen(msg) + 1;
+	unsigned long flags;
+	void *entry_end;
+
+	if (!fbnic_fw_log_ready(fbd)) {
+		dev_err(fbd->dev, "Firmware sent log entry without being requested!\n");
+		return -ENOSPC;
+	}
+
+	spin_lock_irqsave(&log->lock, flags);
+
+	if (list_empty(&log->entries)) {
+		entry = log->data_start;
+	} else {
+		head = list_first_entry(&log->entries, typeof(*head), list);
+		entry = (struct fbnic_fw_log_entry *)&head->msg[head->len + 1];
+		entry = PTR_ALIGN(entry, 8);
+	}
+
+	entry_end = &entry->msg[msg_len + 1];
+
+	/* We've reached the end of the buffer, wrap around */
+	if (entry_end > log->data_end) {
+		entry = log->data_start;
+		entry_end = &entry->msg[msg_len + 1];
+	}
+
+	/* Make room for entry by removing from tail. */
+	list_for_each_entry_safe_reverse(tail, next, &log->entries, list) {
+		if (entry <= tail && entry_end > (void *)tail)
+			list_del(&tail->list);
+		else
+			break;
+	}
+
+	entry->index = index;
+	entry->timestamp = timestamp;
+	entry->len = msg_len;
+	strscpy(entry->msg, msg, entry->len);
+	list_add(&entry->list, &log->entries);
+
+	spin_unlock_irqrestore(&log->lock, flags);
+
+	return 0;
+}
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h
new file mode 100644
index 000000000000..cb6555f40a24
--- /dev/null
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) Meta Platforms, Inc. and affiliates. */
+
+#ifndef _FBNIC_FW_LOG_H_
+#define _FBNIC_FW_LOG_H_
+
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+/* A 512K log buffer was chosen fairly arbitrarily */
+#define FBNIC_FW_LOG_SIZE	(512 * 1024) /* bytes */
+
+/* Firmware log output is prepended with log index followed by a timestamp.
+ * The timestamp is similar to Zephyr's format DD:HH:MM:SS.MMM
+ */
+#define FBNIC_FW_LOG_FMT	"[%5lld] [%02ld:%02ld:%02ld:%02ld.%03ld] %s\n"
+
+struct fbnic_dev;
+
+struct fbnic_fw_log_entry {
+	struct list_head	list;
+	u64			index;
+	u32			timestamp;
+	u16			len;
+	char			msg[] __counted_by(len);
+};
+
+struct fbnic_fw_log {
+	void			*data_start;
+	void			*data_end;
+	size_t			size;
+	struct list_head	entries;
+	/* Spin lock for accessing or modifying entries */
+	spinlock_t		lock;
+};
+
+#define fbnic_fw_log_ready(_fbd)	(!!(_fbd)->fw_log.data_start)
+
+void fbnic_fw_log_enable(struct fbnic_dev *fbd, bool send_hist);
+void fbnic_fw_log_disable(struct fbnic_dev *fbd);
+int fbnic_fw_log_init(struct fbnic_dev *fbd);
+void fbnic_fw_log_free(struct fbnic_dev *fbd);
+int fbnic_fw_log_write(struct fbnic_dev *fbd, u64 index, u32 timestamp,
+		       char *msg);
+#endif /* _FBNIC_FW_LOG_H_ */
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
index 249d3ef862d5..b70e4cadb37b 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
@@ -291,6 +291,17 @@ static int fbnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto free_irqs;
 	}
 
+	/* Send the request to enable the FW logging to host. Note if this
+	 * fails we ignore the error and just display a message as it is
+	 * possible the FW is just too old to support the logging and needs
+	 * to be updated.
+	 */
+	err = fbnic_fw_log_init(fbd);
+	if (err)
+		dev_warn(fbd->dev,
+			 "Unable to initialize firmware log buffer: %d\n",
+			 err);
+
 	fbnic_devlink_register(fbd);
 	fbnic_dbg_fbd_init(fbd);
 	spin_lock_init(&fbd->hw_stats_lock);
@@ -365,6 +376,7 @@ static void fbnic_remove(struct pci_dev *pdev)
 	fbnic_hwmon_unregister(fbd);
 	fbnic_dbg_fbd_exit(fbd);
 	fbnic_devlink_unregister(fbd);
+	fbnic_fw_log_free(fbd);
 	fbnic_fw_free_mbx(fbd);
 	fbnic_free_irqs(fbd);
 
@@ -389,6 +401,8 @@ static int fbnic_pm_suspend(struct device *dev)
 	rtnl_unlock();
 
 null_uc_addr:
+	fbnic_fw_log_disable(fbd);
+
 	devl_lock(priv_to_devlink(fbd));
 
 	fbnic_fw_free_mbx(fbd);
@@ -434,6 +448,11 @@ static int __fbnic_pm_resume(struct device *dev)
 
 	devl_unlock(priv_to_devlink(fbd));
 
+	/* Only send log history if log buffer is empty to prevent duplicate
+	 * log entries.
+	 */
+	fbnic_fw_log_enable(fbd, list_empty(&fbd->fw_log.entries));
+
 	/* No netdev means there isn't a network interface to bring up */
 	if (fbnic_init_failure(fbd))
 		return 0;
@@ -455,6 +474,8 @@ static int __fbnic_pm_resume(struct device *dev)
 
 	return 0;
 err_free_mbx:
+	fbnic_fw_log_disable(fbd);
+
 	rtnl_unlock();
 	fbnic_fw_free_mbx(fbd);
 err_free_irqs: