i40e: Resume Port Tx after DCB event

When there are DCB configuration changes based on DCBX the firmware suspends
the port's Tx and generates an event to the PF. The PF is then responsible
to reconfigure the PF VSIs and switching topology as per the updated DCB
configuration and then resume the port's Tx by calling the "Resume Port Tx"
AQ command.

This patch adds this call to the flow that handles DCB re-configuration in
the PF.

Change-ID: I5b860ad48abfbf379b003143c4d3453e2ed5cc1c
Signed-off-by: Neerav Parikh <neerav.parikh@intel.com>
Tested-By: Jack Morgan <jack.morgan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_common.c

@@ -3216,6 +3216,26 @@ i40e_status i40e_aq_add_rem_control_packet_filter(struct i40e_hw *hw,
 	return status;
 }
 
+/**
+ * i40e_aq_resume_port_tx
+ * @hw: pointer to the hardware structure
+ * @cmd_details: pointer to command details structure or NULL
+ *
+ * Resume port's Tx traffic
+ **/
+i40e_status i40e_aq_resume_port_tx(struct i40e_hw *hw,
+				   struct i40e_asq_cmd_details *cmd_details)
+{
+	struct i40e_aq_desc desc;
+	i40e_status status;
+
+	i40e_fill_default_direct_cmd_desc(&desc, i40e_aqc_opc_resume_port_tx);
+
+	status = i40e_asq_send_command(hw, &desc, NULL, 0, cmd_details);
+
+	return status;
+}
+
 /**
  * i40e_set_pci_config_data - store PCI bus info
  * @hw: pointer to hardware structure

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -4381,6 +4381,31 @@ static void i40e_dcb_reconfigure(struct i40e_pf *pf)
 	}
 }
 
+/**
+ * i40e_resume_port_tx - Resume port Tx
+ * @pf: PF struct
+ *
+ * Resume a port's Tx and issue a PF reset in case of failure to
+ * resume.
+ **/
+static int i40e_resume_port_tx(struct i40e_pf *pf)
+{
+	struct i40e_hw *hw = &pf->hw;
+	int ret;
+
+	ret = i40e_aq_resume_port_tx(hw, NULL);
+	if (ret) {
+		dev_info(&pf->pdev->dev,
+			 "AQ command Resume Port Tx failed = %d\n",
+			  pf->hw.aq.asq_last_status);
+		/* Schedule PF reset to recover */
+		set_bit(__I40E_PF_RESET_REQUESTED, &pf->state);
+		i40e_service_event_schedule(pf);
+	}
+
+	return ret;
+}
+
 /**
  * i40e_init_pf_dcb - Initialize DCB configuration
  * @pf: PF being configured
@@ -5075,7 +5100,11 @@ static int i40e_handle_lldp_event(struct i40e_pf *pf,
 	/* Changes in configuration update VEB/VSI */
 	i40e_dcb_reconfigure(pf);
 
-	i40e_pf_unquiesce_all_vsi(pf);
+	ret = i40e_resume_port_tx(pf);
+
+	/* In case of error no point in resuming VSIs */
+	if (!ret)
+		i40e_pf_unquiesce_all_vsi(pf);
 exit:
 	return ret;
 }

drivers/net/ethernet/intel/i40e/i40e_prototype.h

@@ -230,6 +230,8 @@ i40e_status i40e_aq_query_switch_comp_bw_config(struct i40e_hw *hw,
 		u16 seid,
 		struct i40e_aqc_query_switching_comp_bw_config_resp *bw_data,
 		struct i40e_asq_cmd_details *cmd_details);
+i40e_status i40e_aq_resume_port_tx(struct i40e_hw *hw,
+				   struct i40e_asq_cmd_details *cmd_details);
 /* i40e_common */
 i40e_status i40e_init_shared_code(struct i40e_hw *hw);
 i40e_status i40e_pf_reset(struct i40e_hw *hw);