ice: Add code to control FW LLDP and DCBX

This patch adds code to start or stop LLDP and DCBX in firmware through
use of ethtool private flags.

Signed-off-by: Anirudh Venkataramanan <[e-mail]>
Tested-by: Andrew Bowers <[e-mail]>
Signed-off-by: Jeff Kirsher <[e-mail]>

drivers/net/ethernet/intel/ice/ice.h

···
 	ICE_FLAG_DCB_CAPABLE,
 	ICE_FLAG_DCB_ENA,
 	ICE_FLAG_LINK_DOWN_ON_CLOSE_ENA,
+	ICE_FLAG_DISABLE_FW_LLDP,
+	ICE_FLAG_ETHTOOL_CTXT,		/* set when ethtool holds RTNL lock */
 	ICE_PF_FLAGS_NBITS		/* must be last */
 };
 

drivers/net/ethernet/intel/ice/ice_adminq_cmd.h

···
 	u8 reserved[15];
 };
 
+/* Stop LLDP (direct 0x0A05) */
+struct ice_aqc_lldp_stop {
+	u8 command;
+#define ICE_AQ_LLDP_AGENT_STATE_MASK	BIT(0)
+#define ICE_AQ_LLDP_AGENT_STOP		0x0
+#define ICE_AQ_LLDP_AGENT_SHUTDOWN	ICE_AQ_LLDP_AGENT_STATE_MASK
+#define ICE_AQ_LLDP_AGENT_PERSIST_DIS	BIT(1)
+	u8 reserved[15];
+};
+
 /* Start LLDP (direct 0x0A06) */
 struct ice_aqc_lldp_start {
 	u8 command;
···
 		struct ice_aqc_pf_vf_msg virt;
 		struct ice_aqc_lldp_get_mib lldp_get_mib;
 		struct ice_aqc_lldp_set_mib_change lldp_set_event;
+		struct ice_aqc_lldp_stop lldp_stop;
 		struct ice_aqc_lldp_start lldp_start;
 		struct ice_aqc_lldp_set_local_mib lldp_set_mib;
 		struct ice_aqc_lldp_stop_start_specific_agent lldp_agent_ctrl;
···
 	/* LLDP commands */
 	ice_aqc_opc_lldp_get_mib			= 0x0A00,
 	ice_aqc_opc_lldp_set_mib_change			= 0x0A01,
+	ice_aqc_opc_lldp_stop				= 0x0A05,
 	ice_aqc_opc_lldp_start				= 0x0A06,
 	ice_aqc_opc_get_cee_dcb_cfg			= 0x0A07,
 	ice_aqc_opc_lldp_set_local_mib			= 0x0A08,

drivers/net/ethernet/intel/ice/ice_dcb.c

···
  * Enable or Disable posting of an event on ARQ when LLDP MIB
  * associated with the interface changes (0x0A01)
  */
-static enum ice_status
+enum ice_status
 ice_aq_cfg_lldp_mib_change(struct ice_hw *hw, bool ena_update,
 			   struct ice_sq_cd *cd)
 {
···
 
 	if (!ena_update)
 		cmd->command |= ICE_AQ_LLDP_MIB_UPDATE_DIS;
+
+	return ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
+}
+
+/**
+ * ice_aq_stop_lldp
+ * @hw: pointer to the HW struct
+ * @shutdown_lldp_agent: True if LLDP Agent needs to be Shutdown
+ *			 False if LLDP Agent needs to be Stopped
+ * @cd: pointer to command details structure or NULL
+ *
+ * Stop or Shutdown the embedded LLDP Agent (0x0A05)
+ */
+enum ice_status
+ice_aq_stop_lldp(struct ice_hw *hw, bool shutdown_lldp_agent,
+		 struct ice_sq_cd *cd)
+{
+	struct ice_aqc_lldp_stop *cmd;
+	struct ice_aq_desc desc;
+
+	cmd = &desc.params.lldp_stop;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_lldp_stop);
+
+	if (shutdown_lldp_agent)
+		cmd->command |= ICE_AQ_LLDP_AGENT_SHUTDOWN;
 
 	return ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
 }

drivers/net/ethernet/intel/ice/ice_dcb.h

···
 		   struct ice_aqc_port_ets_elem *buf, u16 buf_size,
 		   struct ice_sq_cd *cmd_details);
 #ifdef CONFIG_DCB
+enum ice_status
+ice_aq_stop_lldp(struct ice_hw *hw, bool shutdown_lldp_agent,
+		 struct ice_sq_cd *cd);
 enum ice_status ice_aq_start_lldp(struct ice_hw *hw, struct ice_sq_cd *cd);
 enum ice_status
 ice_aq_start_stop_dcbx(struct ice_hw *hw, bool start_dcbx_agent,
 		       bool *dcbx_agent_status, struct ice_sq_cd *cd);
+enum ice_status
+ice_aq_cfg_lldp_mib_change(struct ice_hw *hw, bool ena_update,
+			   struct ice_sq_cd *cd);
 #else /* CONFIG_DCB */
+static inline enum ice_status
+ice_aq_stop_lldp(struct ice_hw __always_unused *hw,
+		 bool __always_unused shutdown_lldp_agent,
+		 struct ice_sq_cd __always_unused *cd)
+{
+	return 0;
+}
+
 static inline enum ice_status
 ice_aq_start_lldp(struct ice_hw __always_unused *hw,
 		  struct ice_sq_cd __always_unused *cd)
···
 
 	return 0;
 }
+
+static inline enum ice_status
+ice_aq_cfg_lldp_mib_change(struct ice_hw __always_unused *hw,
+			   bool __always_unused ena_update,
+			   struct ice_sq_cd __always_unused *cd)
+{
+	return 0;
+}
+
 #endif /* CONFIG_DCB */
 #endif /* _ICE_DCB_H_ */

drivers/net/ethernet/intel/ice/ice_ethtool.c

···
 /* ethtool support for ice */
 
 #include "ice.h"
+#include "ice_lib.h"
+#include "ice_dcb_lib.h"
 
 struct ice_stats {
 	char stat_string[ETH_GSTRING_LEN];
···
 
 static const struct ice_priv_flag ice_gstrings_priv_flags[] = {
 	ICE_PRIV_FLAG("link-down-on-close", ICE_FLAG_LINK_DOWN_ON_CLOSE_ENA),
+	ICE_PRIV_FLAG("disable-fw-lldp", ICE_FLAG_DISABLE_FW_LLDP),
 };
 
 #define ICE_PRIV_FLAG_ARRAY_SIZE	ARRAY_SIZE(ice_gstrings_priv_flags)
···
 static int ice_set_priv_flags(struct net_device *netdev, u32 flags)
 {
 	struct ice_netdev_priv *np = netdev_priv(netdev);
+	DECLARE_BITMAP(change_flags, ICE_PF_FLAGS_NBITS);
+	DECLARE_BITMAP(orig_flags, ICE_PF_FLAGS_NBITS);
 	struct ice_vsi *vsi = np->vsi;
 	struct ice_pf *pf = vsi->back;
+	int ret = 0;
 	u32 i;
 
 	if (flags > BIT(ICE_PRIV_FLAG_ARRAY_SIZE))
 		return -EINVAL;
 
+	set_bit(ICE_FLAG_ETHTOOL_CTXT, pf->flags);
+
+	bitmap_copy(orig_flags, pf->flags, ICE_PF_FLAGS_NBITS);
 	for (i = 0; i < ICE_PRIV_FLAG_ARRAY_SIZE; i++) {
 		const struct ice_priv_flag *priv_flag;
 
···
 			clear_bit(priv_flag->bitno, pf->flags);
 	}
 
-	return 0;
+	bitmap_xor(change_flags, pf->flags, orig_flags, ICE_PF_FLAGS_NBITS);
+
+	if (test_bit(ICE_FLAG_DISABLE_FW_LLDP, change_flags)) {
+		if (test_bit(ICE_FLAG_DISABLE_FW_LLDP, pf->flags)) {
+			enum ice_status status;
+
+			status = ice_aq_cfg_lldp_mib_change(&pf->hw, false,
+							    NULL);
+			/* If unregistering for LLDP events fails, this is
+			 * not an error state, as there shouldn't be any
+			 * events to respond to.
+			 */
+			if (status)
+				dev_info(&pf->pdev->dev,
+					 "Failed to unreg for LLDP events\n");
+
+			/* The AQ call to stop the FW LLDP agent will generate
+			 * an error if the agent is already stopped.
+			 */
+			status = ice_aq_stop_lldp(&pf->hw, true, NULL);
+			if (status)
+				dev_warn(&pf->pdev->dev,
+					 "Fail to stop LLDP agent\n");
+			/* Use case for having the FW LLDP agent stopped
+			 * will likely not need DCB, so failure to init is
+			 * not a concern of ethtool
+			 */
+			status = ice_init_pf_dcb(pf);
+			if (status)
+				dev_warn(&pf->pdev->dev, "Fail to init DCB\n");
+		} else {
+			enum ice_status status;
+			bool dcbx_agent_status;
+
+			/* AQ command to start FW LLDP agent will return an
+			 * error if the agent is already started
+			 */
+			status = ice_aq_start_lldp(&pf->hw, NULL);
+			if (status)
+				dev_warn(&pf->pdev->dev,
+					 "Fail to start LLDP Agent\n");
+
+			/* AQ command to start FW DCBx agent will fail if
+			 * the agent is already started
+			 */
+			status = ice_aq_start_stop_dcbx(&pf->hw, true,
+							&dcbx_agent_status,
+							NULL);
+			if (status)
+				dev_dbg(&pf->pdev->dev,
+					"Failed to start FW DCBX\n");
+
+			dev_info(&pf->pdev->dev, "FW DCBX agent is %s\n",
+				 dcbx_agent_status ? "ACTIVE" : "DISABLED");
+
+			/* Failure to configure MIB change or init DCB is not
+			 * relevant to ethtool.  Print notification that
+			 * registration/init failed but do not return error
+			 * state to ethtool
+			 */
+			status = ice_aq_cfg_lldp_mib_change(&pf->hw, false,
+							    NULL);
+			if (status)
+				dev_dbg(&pf->pdev->dev,
+					"Fail to reg for MIB change\n");
+
+			status = ice_init_pf_dcb(pf);
+			if (status)
+				dev_dbg(&pf->pdev->dev, "Fail to init DCB\n");
+		}
+	}
+	clear_bit(ICE_FLAG_ETHTOOL_CTXT, pf->flags);
+	return ret;
 }
 
 static int ice_get_sset_count(struct net_device *netdev, int sset)
···
 	struct ice_port_info *pi = np->vsi->port_info;
 	struct ice_aqc_get_phy_caps_data *pcaps;
 	struct ice_vsi *vsi = np->vsi;
+	struct ice_dcbx_cfg *dcbx_cfg;
 	enum ice_status status;
 
 	/* Initialize pause params */
 	pause->rx_pause = 0;
 	pause->tx_pause = 0;
+
+	dcbx_cfg = &pi->local_dcbx_cfg;
 
 	pcaps = devm_kzalloc(&vsi->back->pdev->dev, sizeof(*pcaps),
 			     GFP_KERNEL);
···
 
 	pause->autoneg = ((pcaps->caps & ICE_AQC_PHY_AN_MODE) ?
 			AUTONEG_ENABLE : AUTONEG_DISABLE);
+
+	if (dcbx_cfg->pfc.pfcena)
+		/* PFC enabled so report LFC as off */
+		goto out;
 
 	if (pcaps->caps & ICE_AQC_PHY_EN_TX_LINK_PAUSE)
 		pause->tx_pause = 1;
···
 	struct ice_netdev_priv *np = netdev_priv(netdev);
 	struct ice_link_status *hw_link_info;
 	struct ice_pf *pf = np->vsi->back;
+	struct ice_dcbx_cfg *dcbx_cfg;
 	struct ice_vsi *vsi = np->vsi;
 	struct ice_hw *hw = &pf->hw;
 	struct ice_port_info *pi;
···
 
 	pi = vsi->port_info;
 	hw_link_info = &pi->phy.link_info;
+	dcbx_cfg = &pi->local_dcbx_cfg;
 	link_up = hw_link_info->link_info & ICE_AQ_LINK_UP;
 
 	/* Changing the port's flow control is not supported if this isn't the
···
 		netdev_info(netdev, "Autoneg did not complete so changing settings may not result in an actual change.\n");
 	}
 
+	if (dcbx_cfg->pfc.pfcena) {
+		netdev_info(netdev, "Priority flow control enabled. Cannot set link flow control.\n");
+		return -EOPNOTSUPP;
+	}
 	if (pause->rx_pause && pause->tx_pause)
 		pi->fc.req_mode = ICE_FC_FULL;
 	else if (pause->rx_pause && !pause->tx_pause)