i40e: Add init and default config of software based DCB

Add extra handling on changing the "disable-fw-lldp" private
flag to properly initialize software based DCB feature.

Add default configuration of DCB functionality when Firmware
LLDP agent is turned off, in case of driver probe and device
reset on reconfiguration.

Update copyright dates as appropriate.

Software based DCB is a brand-new feature in i40e driver.
Before, DCB was implemented by Firmware LLDP agent only. The agent was
responsible for handling incoming DCB-related LLDP frames and
applying received DCB configuration to hardware.

Default configuration and new initialization flow for software based
DCB is required. If LLDP agent is turned off in BIOS, or after
setting private flag ("disable-fw-lldp on"). The driver initializes
DCB functionality with default values, one traffic class with 100%
bandwidth allocated.

Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/i40e/i40e.h

@@ -1,5 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-/* Copyright(c) 2013 - 2018 Intel Corporation. */
+/* Copyright(c) 2013 - 2021 Intel Corporation. */
 
 #ifndef _I40E_H_
 #define _I40E_H_
@@ -289,6 +289,9 @@ struct i40e_cloud_filter {
 	u8 tunnel_type;
 };
 
+#define I40E_DCB_PRIO_TYPE_STRICT	0
+#define I40E_DCB_PRIO_TYPE_ETS		1
+#define I40E_DCB_STRICT_PRIO_CREDITS	127
 /* DCB per TC information data structure */
 struct i40e_tc_info {
 	u16	qoffset;	/* Queue offset from base queue */
@@ -626,6 +629,8 @@ struct i40e_pf {
 	u16 dcbx_cap;
 
 	struct i40e_filter_control_settings filter_settings;
+	struct i40e_rx_pb_config pb_cfg; /* Current Rx packet buffer config */
+	struct i40e_dcbx_config tmp_cfg;
 
 	struct ptp_clock *ptp_clock;
 	struct ptp_clock_info ptp_caps;
@@ -1122,6 +1127,12 @@ bool i40e_is_vsi_in_vlan(struct i40e_vsi *vsi);
 int i40e_count_filters(struct i40e_vsi *vsi);
 struct i40e_mac_filter *i40e_find_mac(struct i40e_vsi *vsi, const u8 *macaddr);
 void i40e_vlan_stripping_enable(struct i40e_vsi *vsi);
+static inline bool i40e_is_sw_dcb(struct i40e_pf *pf)
+{
+	return !!(pf->flags & I40E_FLAG_DISABLE_FW_LLDP);
+}
+
+void i40e_set_lldp_forwarding(struct i40e_pf *pf, bool enable);
 #ifdef CONFIG_I40E_DCB
 void i40e_dcbnl_flush_apps(struct i40e_pf *pf,
 			   struct i40e_dcbx_config *old_cfg,
@@ -1131,6 +1142,8 @@ void i40e_dcbnl_setup(struct i40e_vsi *vsi);
 bool i40e_dcb_need_reconfig(struct i40e_pf *pf,
 			    struct i40e_dcbx_config *old_cfg,
 			    struct i40e_dcbx_config *new_cfg);
+int i40e_hw_dcb_config(struct i40e_pf *pf, struct i40e_dcbx_config *new_cfg);
+int i40e_dcb_sw_default_config(struct i40e_pf *pf);
 #endif /* CONFIG_I40E_DCB */
 void i40e_ptp_rx_hang(struct i40e_pf *pf);
 void i40e_ptp_tx_hang(struct i40e_pf *pf);

drivers/net/ethernet/intel/i40e/i40e_ethtool.c

@@ -5033,23 +5033,13 @@ static int i40e_set_priv_flags(struct net_device *dev, u32 flags)
 
 	if (changed_flags & I40E_FLAG_DISABLE_FW_LLDP) {
 		if (new_flags & I40E_FLAG_DISABLE_FW_LLDP) {
-			struct i40e_dcbx_config *dcbcfg;
-
+#ifdef CONFIG_I40E_DCB
+			i40e_dcb_sw_default_config(pf);
+#endif /* CONFIG_I40E_DCB */
+			i40e_aq_cfg_lldp_mib_change_event(&pf->hw, false, NULL);
 			i40e_aq_stop_lldp(&pf->hw, true, false, NULL);
-			i40e_aq_set_dcb_parameters(&pf->hw, true, NULL);
-			/* reset local_dcbx_config to default */
-			dcbcfg = &pf->hw.local_dcbx_config;
-			dcbcfg->etscfg.willing = 1;
-			dcbcfg->etscfg.maxtcs = 0;
-			dcbcfg->etscfg.tcbwtable[0] = 100;
-			for (i = 1; i < I40E_MAX_TRAFFIC_CLASS; i++)
-				dcbcfg->etscfg.tcbwtable[i] = 0;
-			for (i = 0; i < I40E_MAX_USER_PRIORITY; i++)
-				dcbcfg->etscfg.prioritytable[i] = 0;
-			dcbcfg->etscfg.tsatable[0] = I40E_IEEE_TSA_ETS;
-			dcbcfg->pfc.willing = 1;
-			dcbcfg->pfc.pfccap = I40E_MAX_TRAFFIC_CLASS;
 		} else {
+			i40e_set_lldp_forwarding(pf, false);
 			status = i40e_aq_start_lldp(&pf->hw, false, NULL);
 			if (status) {
 				adq_err = pf->hw.aq.asq_last_status;