ice: configure FW logging

Users want the ability to debug FW issues by retrieving the
FW logs from the E8xx devices. Use debugfs to allow the user to
configure the log level and number of messages for FW logging.

If FW logging is supported on the E8xx then the file 'fwlog' will be
created under the PCI device ID for the ice driver. If the file does not
exist then either the E8xx doesn't support FW logging or debugfs is not
enabled on the system.

One thing users want to do is control which events are reported. The
user can read and write the 'fwlog/modules/<module name>' to get/set
the log levels. Each module in the FW that supports logging ht as a file
under 'fwlog/modules' that supports reading (to see what the current log
level is) and writing (to change the log level).

The format to set the log levels for a module are:

  # echo <log level> > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/<module>

The supported log levels are:

      *	none
      *	error
      *	warning
      *	normal
      *	verbose

Each level includes the messages from the previous/lower level

The modules that are supported are:

      *	general
      *	ctrl
      *	link
      *	link_topo
      *	dnl
      *	i2c
      *	sdp
      *	mdio
      *	adminq
      *	hdma
      *	lldp
      *	dcbx
      *	dcb
      *	xlr
      *	nvm
      *	auth
      *	vpd
      *	iosf
      *	parser
      *	sw
      *	scheduler
      *	txq
      *	rsvd
      *	post
      *	watchdog
      *	task_dispatch
      *	mng
      *	synce
      *	health
      *	tsdrv
      *	pfreg
      *	mdlver
      *	all

The module 'all' is a special module which allows the user to read or
write to all of the modules.

The following example command would set the DCB module to the 'normal'
log level:

  # echo normal > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/dcb

If the user wants to set the DCB, Link, and the AdminQ modules to
'verbose' then the commands are:

  # echo verbose > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/dcb
  # echo verbose > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/link
  # echo verbose > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/adminq

If the user wants to set all modules to the 'warning' level then the
command is:

  # echo warning > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/all

If the user wants to disable logging for a module then they can set the
level to 'none'. An example setting the 'watchdog' module is:

  # echo none > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/watchdog

If the user wants to see what the log level is for a specific module
then the command is:

  # cat /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/dcb

This will return the log level for the DCB module. If the user wants to
see the log level for all the modules then the command is:

  # cat /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/modules/all

Writing to the module file will update the configuration, but NOT enable the
configuration (that is a separate command).

In addition to configuring the modules, the user can also configure the
number of log messages (nr_messages) to include in a single Admin Receive
Queue (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.

To see/change the resolution the user can read/write the
'fwlog/nr_messages' file. An example changing the value to 50 is

  # echo 50 > /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/nr_messages

To see the current value of 'nr_messages' then the command is:

  # cat /sys/kernel/debug/ice/0000\:18\:00.0/fwlog/nr_messages

Signed-off-by: Paul M Stillwell Jr <paul.m.stillwell.jr@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 261 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_fwlog.c b/drivers/net/ethernet/intel/ice/ice_fwlog.c
new file mode 100644
index 000000000000..307e0d04f3fe
--- /dev/null
+++ b/drivers/net/ethernet/intel/ice/ice_fwlog.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022, Intel Corporation. */
+
+#include "ice.h"
+#include "ice_common.h"
+#include "ice_fwlog.h"
+
+/**
+ * ice_fwlog_init - Initialize FW logging configuration
+ * @hw: pointer to the HW structure
+ *
+ * This function should be called on driver initialization during
+ * ice_init_hw().
+ */
+int ice_fwlog_init(struct ice_hw *hw)
+{
+	/* only support fw log commands on PF 0 */
+	if (hw->bus.func)
+		return -EINVAL;
+
+	ice_fwlog_set_supported(hw);
+
+	if (ice_fwlog_supported(hw)) {
+		int status;
+
+		/* read the current config from the FW and store it */
+		status = ice_fwlog_get(hw, &hw->fwlog_cfg);
+		if (status)
+			return status;
+
+		ice_debugfs_fwlog_init(hw->back);
+	} else {
+		dev_warn(ice_hw_to_dev(hw), "FW logging is not supported in this NVM image. Please update the NVM to get FW log support\n");
+	}
+
+	return 0;
+}
+
+/**
+ * ice_fwlog_deinit - unroll FW logging configuration
+ * @hw: pointer to the HW structure
+ *
+ * This function should be called in ice_deinit_hw().
+ */
+void ice_fwlog_deinit(struct ice_hw *hw)
+{
+	struct ice_pf *pf = hw->back;
+	int status;
+
+	/* only support fw log commands on PF 0 */
+	if (hw->bus.func)
+		return;
+
+	/* make sure FW logging is disabled to not put the FW in a weird state
+	 * for the next driver load
+	 */
+	hw->fwlog_cfg.options &= ~ICE_FWLOG_OPTION_ARQ_ENA;
+	status = ice_fwlog_set(hw, &hw->fwlog_cfg);
+	if (status)
+		dev_warn(ice_hw_to_dev(hw), "Unable to turn off FW logging, status: %d\n",
+			 status);
+
+	kfree(pf->ice_debugfs_pf_fwlog_modules);
+
+	pf->ice_debugfs_pf_fwlog_modules = NULL;
+}
+
+/**
+ * ice_fwlog_supported - Cached for whether FW supports FW logging or not
+ * @hw: pointer to the HW structure
+ *
+ * This will always return false if called before ice_init_hw(), so it must be
+ * called after ice_init_hw().
+ */
+bool ice_fwlog_supported(struct ice_hw *hw)
+{
+	return hw->fwlog_supported;
+}
+
+/**
+ * ice_aq_fwlog_set - Set FW logging configuration AQ command (0xFF30)
+ * @hw: pointer to the HW structure
+ * @entries: entries to configure
+ * @num_entries: number of @entries
+ * @options: options from ice_fwlog_cfg->options structure
+ * @log_resolution: logging resolution
+ */
+static int
+ice_aq_fwlog_set(struct ice_hw *hw, struct ice_fwlog_module_entry *entries,
+		 u16 num_entries, u16 options, u16 log_resolution)
+{
+	struct ice_aqc_fw_log_cfg_resp *fw_modules;
+	struct ice_aqc_fw_log *cmd;
+	struct ice_aq_desc desc;
+	int status;
+	int i;
+
+	fw_modules = kcalloc(num_entries, sizeof(*fw_modules), GFP_KERNEL);
+	if (!fw_modules)
+		return -ENOMEM;
+
+	for (i = 0; i < num_entries; i++) {
+		fw_modules[i].module_identifier =
+			cpu_to_le16(entries[i].module_id);
+		fw_modules[i].log_level = entries[i].log_level;
+	}
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_fw_logs_config);
+	desc.flags |= cpu_to_le16(ICE_AQ_FLAG_RD);
+
+	cmd = &desc.params.fw_log;
+
+	cmd->cmd_flags = ICE_AQC_FW_LOG_CONF_SET_VALID;
+	cmd->ops.cfg.log_resolution = cpu_to_le16(log_resolution);
+	cmd->ops.cfg.mdl_cnt = cpu_to_le16(num_entries);
+
+	if (options & ICE_FWLOG_OPTION_ARQ_ENA)
+		cmd->cmd_flags |= ICE_AQC_FW_LOG_CONF_AQ_EN;
+	if (options & ICE_FWLOG_OPTION_UART_ENA)
+		cmd->cmd_flags |= ICE_AQC_FW_LOG_CONF_UART_EN;
+
+	status = ice_aq_send_cmd(hw, &desc, fw_modules,
+				 sizeof(*fw_modules) * num_entries,
+				 NULL);
+
+	kfree(fw_modules);
+
+	return status;
+}
+
+/**
+ * ice_fwlog_set - Set the firmware logging settings
+ * @hw: pointer to the HW structure
+ * @cfg: config used to set firmware logging
+ *
+ * This function should be called whenever the driver needs to set the firmware
+ * logging configuration. It can be called on initialization, reset, or during
+ * runtime.
+ *
+ * If the PF wishes to receive FW logging then it must register via
+ * ice_fwlog_register. Note, that ice_fwlog_register does not need to be called
+ * for init.
+ */
+int ice_fwlog_set(struct ice_hw *hw, struct ice_fwlog_cfg *cfg)
+{
+	if (!ice_fwlog_supported(hw))
+		return -EOPNOTSUPP;
+
+	return ice_aq_fwlog_set(hw, cfg->module_entries,
+				ICE_AQC_FW_LOG_ID_MAX, cfg->options,
+				cfg->log_resolution);
+}
+
+/**
+ * ice_aq_fwlog_get - Get the current firmware logging configuration (0xFF32)
+ * @hw: pointer to the HW structure
+ * @cfg: firmware logging configuration to populate
+ */
+static int ice_aq_fwlog_get(struct ice_hw *hw, struct ice_fwlog_cfg *cfg)
+{
+	struct ice_aqc_fw_log_cfg_resp *fw_modules;
+	struct ice_aqc_fw_log *cmd;
+	struct ice_aq_desc desc;
+	u16 module_id_cnt;
+	int status;
+	void *buf;
+	int i;
+
+	memset(cfg, 0, sizeof(*cfg));
+
+	buf = kzalloc(ICE_AQ_MAX_BUF_LEN, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_fw_logs_query);
+	cmd = &desc.params.fw_log;
+
+	cmd->cmd_flags = ICE_AQC_FW_LOG_AQ_QUERY;
+
+	status = ice_aq_send_cmd(hw, &desc, buf, ICE_AQ_MAX_BUF_LEN, NULL);
+	if (status) {
+		ice_debug(hw, ICE_DBG_FW_LOG, "Failed to get FW log configuration\n");
+		goto status_out;
+	}
+
+	module_id_cnt = le16_to_cpu(cmd->ops.cfg.mdl_cnt);
+	if (module_id_cnt < ICE_AQC_FW_LOG_ID_MAX) {
+		ice_debug(hw, ICE_DBG_FW_LOG, "FW returned less than the expected number of FW log module IDs\n");
+	} else if (module_id_cnt > ICE_AQC_FW_LOG_ID_MAX) {
+		ice_debug(hw, ICE_DBG_FW_LOG, "FW returned more than expected number of FW log module IDs, setting module_id_cnt to software expected max %u\n",
+			  ICE_AQC_FW_LOG_ID_MAX);
+		module_id_cnt = ICE_AQC_FW_LOG_ID_MAX;
+	}
+
+	cfg->log_resolution = le16_to_cpu(cmd->ops.cfg.log_resolution);
+	if (cmd->cmd_flags & ICE_AQC_FW_LOG_CONF_AQ_EN)
+		cfg->options |= ICE_FWLOG_OPTION_ARQ_ENA;
+	if (cmd->cmd_flags & ICE_AQC_FW_LOG_CONF_UART_EN)
+		cfg->options |= ICE_FWLOG_OPTION_UART_ENA;
+
+	fw_modules = (struct ice_aqc_fw_log_cfg_resp *)buf;
+
+	for (i = 0; i < module_id_cnt; i++) {
+		struct ice_aqc_fw_log_cfg_resp *fw_module = &fw_modules[i];
+
+		cfg->module_entries[i].module_id =
+			le16_to_cpu(fw_module->module_identifier);
+		cfg->module_entries[i].log_level = fw_module->log_level;
+	}
+
+status_out:
+	kfree(buf);
+	return status;
+}
+
+/**
+ * ice_fwlog_get - Get the firmware logging settings
+ * @hw: pointer to the HW structure
+ * @cfg: config to populate based on current firmware logging settings
+ */
+int ice_fwlog_get(struct ice_hw *hw, struct ice_fwlog_cfg *cfg)
+{
+	if (!ice_fwlog_supported(hw))
+		return -EOPNOTSUPP;
+
+	return ice_aq_fwlog_get(hw, cfg);
+}
+
+/**
+ * ice_fwlog_set_supported - Set if FW logging is supported by FW
+ * @hw: pointer to the HW struct
+ *
+ * If FW returns success to the ice_aq_fwlog_get call then it supports FW
+ * logging, else it doesn't. Set the fwlog_supported flag accordingly.
+ *
+ * This function is only meant to be called during driver init to determine if
+ * the FW support FW logging.
+ */
+void ice_fwlog_set_supported(struct ice_hw *hw)
+{
+	struct ice_fwlog_cfg *cfg;
+	int status;
+
+	hw->fwlog_supported = false;
+
+	cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+	if (!cfg)
+		return;
+
+	/* don't call ice_fwlog_get() because that would check to see if FW
+	 * logging is supported which is what the driver is determining now
+	 */
+	status = ice_aq_fwlog_get(hw, cfg);
+	if (status)
+		ice_debug(hw, ICE_DBG_FW_LOG, "ice_aq_fwlog_get failed, FW logging is not supported on this version of FW, status %d\n",
+			  status);
+	else
+		hw->fwlog_supported = true;
+
+	kfree(cfg);
+}