[net-next,v8,5/5] ice: use debugfs to output FW log data

diff --git a/Documentation/networking/devlink/ice.rst b/Documentation/networking/devlink/ice.rst
index 625efb3777d5..546a618ae7a2 100644
--- a/Documentation/networking/devlink/ice.rst
+++ b/Documentation/networking/devlink/ice.rst
@@ -7,6 +7,45 @@  ice devlink support
 This document describes the devlink features implemented by the ``ice``
 device driver.
 
+Parameters
+=============
+
+.. list-table:: Driver-specific parameters implemented
+   :widths: 5 5 5 85
+
+   * - Name
+     - Type
+     - Mode
+     - Description
+   * - ``fwlog_supported``
+     - Boolean
+     - runtime
+     - This parameter indicates to the user whether FW loggiing is supported
+       or not in the currently loaded FW.
+   * - ``fwlog_enabled``
+     - Boolean
+     - runtime
+     - This parameter indicates to the user whether the driver is currently
+       getting FW logs or not.
+   * - ``fwlog_level``
+     - u8
+     - runtime
+     - This parameter indicates the current log level. Each level includes the
+       messages from the previous/lower level. Valid values are
+
+          * ``0`` - no logging
+          * ``1`` - error logging
+          * ``2`` - warning logging
+          * ``3`` - normal logging
+          * ``4`` - verbose logging
+   * - ``fwlog_resolution``
+     - u8
+     - runtime
+     - This parameter indicates the number of log messages to included in a
+       single ARQ event. The range is 1-128 (1 means push every log message,
+       128 means push only when the max AQ command buffer is full). The
+       suggested value is 10.
+
 Info versions
 =============
 
diff --git a/drivers/net/ethernet/intel/ice/Makefile b/drivers/net/ethernet/intel/ice/Makefile
index 6e4680ad097c..452a440a9810 100644
--- a/drivers/net/ethernet/intel/ice/Makefile
+++ b/drivers/net/ethernet/intel/ice/Makefile
@@ -34,7 +34,8 @@  ice-y := ice_main.o	\
 	 ice_ethtool.o  \
 	 ice_repr.o	\
 	 ice_tc_lib.o	\
-	 ice_fwlog.o
+	 ice_fwlog.o	\
+	 ice_debugfs.o
 ice-$(CONFIG_PCI_IOV) +=	\
 	ice_sriov.o		\
 	ice_virtchnl.o		\
@@ -49,3 +50,4 @@  ice-$(CONFIG_RFS_ACCEL) += ice_arfs.o
 ice-$(CONFIG_XDP_SOCKETS) += ice_xsk.o
 ice-$(CONFIG_ICE_SWITCHDEV) += ice_eswitch.o
 ice-$(CONFIG_ICE_GNSS) += ice_gnss.o
+ice-$(CONFIG_DEBUG_FS) += ice_debugfs.o
diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index cd81974822cc..252f6c0acf99 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -552,6 +552,7 @@  struct ice_pf {
 	struct ice_vsi_stats **vsi_stats;
 	struct ice_sw *first_sw;	/* first switch created by firmware */
 	u16 eswitch_mode;		/* current mode of eswitch */
+	struct dentry *ice_debugfs_pf;
 	struct ice_vfs vfs;
 	DECLARE_BITMAP(features, ICE_F_MAX);
 	DECLARE_BITMAP(state, ICE_STATE_NBITS);
@@ -634,6 +635,8 @@  struct ice_pf {
 #define ICE_VF_AGG_NODE_ID_START	65
 #define ICE_MAX_VF_AGG_NODES		32
 	struct ice_agg_node vf_agg_node[ICE_MAX_VF_AGG_NODES];
+	struct list_head fwlog_data_list;
+	u8 fwlog_list_count;
 };
 
 struct ice_netdev_priv {
@@ -648,6 +651,15 @@  struct ice_netdev_priv {
 	struct list_head tc_indr_block_priv_list;
 };
 
+struct ice_fwlog_data {
+	struct list_head list;
+	u16 data_size;
+	u8 *data;
+};
+
+/* define the maximum number of items that can be in the list */
+#define ICE_FWLOG_MAX_SIZE	128
+
 /**
  * ice_vector_ch_enabled
  * @qv: pointer to q_vector, can be NULL
@@ -872,6 +884,16 @@  static inline bool ice_is_adq_active(struct ice_pf *pf)
 	return false;
 }
 
+#ifdef CONFIG_DEBUG_FS
+void ice_debugfs_fwlog_init(struct ice_pf *pf);
+void ice_debugfs_init(void);
+void ice_debugfs_exit(void);
+#else
+static inline void ice_debugfs_fwlog_init(struct ice_pf *pf) { }
+static inline void ice_debugfs_init(void) { }
+static inline void ice_debugfs_exit(void) { }
+#endif /* CONFIG_DEBUG_FS */
+
 bool netif_is_ice(struct net_device *dev);
 int ice_vsi_setup_tx_rings(struct ice_vsi *vsi);
 int ice_vsi_setup_rx_rings(struct ice_vsi *vsi);
diff --git a/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h b/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
index 1af036beeb45..27c2cea29c51 100644
--- a/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
+++ b/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
@@ -2377,6 +2377,7 @@  enum ice_adminq_opc {
 	ice_aqc_opc_fw_logs_config			= 0xFF30,
 	ice_aqc_opc_fw_logs_register			= 0xFF31,
 	ice_aqc_opc_fw_logs_query			= 0xFF32,
+	ice_aqc_opc_fw_logs_event			= 0xFF33,
 };
 
 #endif /* _ICE_ADMINQ_CMD_H_ */
diff --git a/drivers/net/ethernet/intel/ice/ice_debugfs.c b/drivers/net/ethernet/intel/ice/ice_debugfs.c
new file mode 100644
index 000000000000..c097e9465070
--- /dev/null
+++ b/drivers/net/ethernet/intel/ice/ice_debugfs.c
@@ -0,0 +1,116 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022, Intel Corporation. */
+
+#include <linux/vmalloc.h>
+
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/random.h>
+#include "ice.h"
+
+static struct dentry *ice_debugfs_root;
+
+/**
+ * ice_debugfs_command_read - read from command datum
+ * @filp: the opened file
+ * @buffer: where to write the data for the user to read
+ * @count: the size of the user's buffer
+ * @ppos: file position offset
+ */
+static ssize_t ice_debugfs_command_read(struct file *filp, char __user *buffer,
+					size_t count, loff_t *ppos)
+{
+	struct ice_pf *pf = filp->private_data;
+	struct ice_fwlog_data *log, *tmp_log;
+	int data_copied = 0;
+	int copy_count = 0;
+
+	if (list_empty(&pf->fwlog_data_list))
+		return 0;
+
+	list_for_each_entry(log, &pf->fwlog_data_list, list) {
+		u16 cur_buf_len = log->data_size;
+		int retval;
+
+		if (cur_buf_len >= count)
+			break;
+
+		retval = copy_to_user(buffer, log->data, cur_buf_len);
+		if (retval)
+			return -EFAULT;
+
+		data_copied += cur_buf_len;
+		buffer += cur_buf_len;
+		count -= cur_buf_len;
+		*ppos += cur_buf_len;
+		copy_count++;
+	}
+
+	/* only free the data once we know there weren't any errors */
+	list_for_each_entry_safe(log, tmp_log, &pf->fwlog_data_list, list) {
+		if (!copy_count)
+			break;
+
+		vfree(log->data);
+		list_del(&log->list);
+		vfree(log);
+		pf->fwlog_list_count--;
+		copy_count--;
+	}
+
+	return data_copied;
+}
+
+static const struct file_operations ice_debugfs_command_fops = {
+	.owner = THIS_MODULE,
+	.open  = simple_open,
+	.read = ice_debugfs_command_read,
+};
+
+/**
+ * ice_debugfs_fwlog_init - setup the debugfs directory
+ * @pf: the ice that is starting up
+ */
+void ice_debugfs_fwlog_init(struct ice_pf *pf)
+{
+	const char *name = pci_name(pf->pdev);
+	struct dentry *pfile;
+
+	/* only support fw log commands on PF 0 */
+	if (pf->hw.bus.func)
+		return;
+
+	pf->ice_debugfs_pf = debugfs_create_dir(name, ice_debugfs_root);
+	if (IS_ERR(pf->ice_debugfs_pf))
+		return;
+
+	pfile = debugfs_create_file("fwlog", 0400, pf->ice_debugfs_pf, pf,
+				    &ice_debugfs_command_fops);
+	if (!pfile)
+		goto create_failed;
+
+	return;
+
+create_failed:
+	dev_err(ice_pf_to_dev(pf), "debugfs dir/file for %s failed\n", name);
+	debugfs_remove_recursive(pf->ice_debugfs_pf);
+}
+
+/**
+ * ice_debugfs_init - create root directory for debugfs entries
+ */
+void ice_debugfs_init(void)
+{
+	ice_debugfs_root = debugfs_create_dir(KBUILD_MODNAME, NULL);
+	if (IS_ERR(ice_debugfs_root))
+		pr_info("init of debugfs failed\n");
+}
+
+/**
+ * ice_debugfs_exit - remove debugfs entries
+ */
+void ice_debugfs_exit(void)
+{
+	debugfs_remove_recursive(ice_debugfs_root);
+	ice_debugfs_root = NULL;
+}
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 46d9f7383e06..72f16e4fbd73 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -5,6 +5,7 @@ 
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/vmalloc.h>
 #include <generated/utsrelease.h>
 #include "ice.h"
 #include "ice_base.h"
@@ -1369,6 +1370,43 @@  ice_handle_link_event(struct ice_pf *pf, struct ice_rq_event_info *event)
 	return status;
 }
 
+/**
+ * ice_get_fwlog_data - copy the FW log data from ARQ event
+ * @pf: PF that the FW log event is associated with
+ * @event: event structure containing FW log data
+ */
+static void
+ice_get_fwlog_data(struct ice_pf *pf, struct ice_rq_event_info *event)
+{
+	struct device *dev = ice_pf_to_dev(pf);
+	struct ice_fwlog_data *fwlog;
+
+	if (pf->fwlog_list_count >= ICE_FWLOG_MAX_SIZE)
+		return;
+
+	fwlog = vmalloc(sizeof(*fwlog));
+	if (!fwlog) {
+		dev_warn(dev, "Couldn't allocate memory for FWlog element\n");
+		return;
+	}
+
+	INIT_LIST_HEAD(&fwlog->list);
+
+	fwlog->data_size = le16_to_cpu(event->desc.datalen);
+	fwlog->data = vzalloc(fwlog->data_size);
+	if (!fwlog->data) {
+		dev_warn(dev, "Couldn't allocate memory for FWlog data\n");
+		vfree(fwlog);
+		return;
+	}
+
+	memcpy(fwlog->data, event->msg_buf, fwlog->data_size);
+
+	list_add_tail(&fwlog->list, &pf->fwlog_data_list);
+
+	pf->fwlog_list_count++;
+}
+
 enum ice_aq_task_state {
 	ICE_AQ_TASK_WAITING = 0,
 	ICE_AQ_TASK_COMPLETE,
@@ -1642,6 +1680,9 @@  static int __ice_clean_ctrlq(struct ice_pf *pf, enum ice_ctl_q q_type)
 			if (!ice_is_malicious_vf(pf, &event, i, pending))
 				ice_vc_process_vf_msg(pf, &event);
 			break;
+		case ice_aqc_opc_fw_logs_event:
+			ice_get_fwlog_data(pf, &event);
+			break;
 		case ice_aqc_opc_lldp_set_mib_change:
 			ice_dcb_process_lldp_set_mib_change(pf, &event);
 			break;
@@ -4679,33 +4720,6 @@  static void ice_unregister_netdev(struct ice_vsi *vsi)
 	clear_bit(ICE_VSI_NETDEV_REGISTERED, vsi->state);
 }
 
-/**
- * ice_pf_fwlog_deinit - clear FW logging metadata on device exit
- * @pf: pointer to the PF struct
- */
-static void ice_pf_fwlog_deinit(struct ice_pf *pf)
-{
-	struct ice_hw *hw = &pf->hw;
-
-	/* make sure FW logging is disabled to not put the FW in a weird state
-	 * for the next driver load
-	 */
-	if (hw->fwlog_ena) {
-		int status;
-
-		hw->fwlog_cfg.options &= ~ICE_FWLOG_OPTION_ARQ_ENA;
-		status = ice_fwlog_set(hw, &hw->fwlog_cfg);
-		if (status)
-			dev_warn(ice_pf_to_dev(pf), "Unable to turn off FW logging, status: %d\n",
-				 status);
-
-		status = ice_fwlog_unregister(hw);
-		if (status)
-			dev_warn(ice_pf_to_dev(pf), "Unable to unregister FW logging, status: %d\n",
-				 status);
-	}
-}
-
 /**
  * ice_cfg_netdev - Allocate, configure and register a netdev
  * @vsi: the VSI associated with the new netdev
@@ -4832,6 +4846,56 @@  static void ice_deinit_eth(struct ice_pf *pf)
 	ice_decfg_netdev(vsi);
 }
 
+/**
+ * ice_pf_fwlog_init - initialize FW logging on device init
+ * @pf: pointer to the PF struct
+ */
+static void ice_pf_fwlog_init(struct ice_pf *pf)
+{
+	/* only supported on PF 0 */
+	if (pf->hw.bus.func)
+		return;
+
+	INIT_LIST_HEAD(&pf->fwlog_data_list);
+}
+
+/**
+ * ice_pf_fwlog_deinit - clear FW logging metadata on device exit
+ * @pf: pointer to the PF struct
+ */
+static void ice_pf_fwlog_deinit(struct ice_pf *pf)
+{
+	struct ice_fwlog_data *fwlog, *fwlog_tmp;
+	struct ice_hw *hw = &pf->hw;
+
+	/* only supported on PF 0 */
+	if (pf->hw.bus.func)
+		return;
+
+	/* make sure FW logging is disabled to not put the FW in a weird state
+	 * for the next driver load
+	 */
+	if (hw->fwlog_ena) {
+		int status;
+
+		hw->fwlog_cfg.options &= ~ICE_FWLOG_OPTION_ARQ_ENA;
+		status = ice_fwlog_set(hw, &hw->fwlog_cfg);
+		if (status)
+			dev_warn(ice_pf_to_dev(pf), "Unable to turn off FW logging, status: %d\n",
+				 status);
+
+		status = ice_fwlog_unregister(hw);
+		if (status)
+			dev_warn(ice_pf_to_dev(pf), "Unable to unregister FW logging, status: %d\n",
+				 status);
+	}
+
+	list_for_each_entry_safe(fwlog, fwlog_tmp, &pf->fwlog_data_list, list) {
+		vfree(fwlog->data);
+		vfree(fwlog);
+	}
+}
+
 static int ice_init_dev(struct ice_pf *pf)
 {
 	struct device *dev = ice_pf_to_dev(pf);
@@ -5334,6 +5398,9 @@  ice_probe(struct pci_dev *pdev, const struct pci_device_id __always_unused *ent)
 		hw->debug_mask = debug;
 #endif
 
+	ice_pf_fwlog_init(pf);
+	ice_debugfs_fwlog_init(pf);
+
 	err = ice_init(pf);
 	if (err)
 		goto err_init;
@@ -5444,6 +5511,7 @@  static void ice_remove(struct pci_dev *pdev)
 	}
 
 	ice_pf_fwlog_deinit(pf);
+	ice_debugfs_exit();
 
 	if (test_bit(ICE_FLAG_SRIOV_ENA, pf->flags)) {
 		set_bit(ICE_VF_RESETS_DISABLED, pf->state);
@@ -5907,10 +5975,13 @@  static int __init ice_module_init(void)
 		return -ENOMEM;
 	}
 
+	ice_debugfs_init();
+
 	status = pci_register_driver(&ice_driver);
 	if (status) {
 		pr_err("failed to register PCI driver, err %d\n", status);
 		destroy_workqueue(ice_wq);
+		ice_debugfs_exit();
 	}
 
 	return status;