i40e/i40evf: Add WB_ON_ITR offload support

X722 has a way to work around the descriptor WB issue,
this offload helps turn that feature on.

Change-ID: I7ffa67622426bfca5a651417b63e3afcfeb60412
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_virtchnl.h

@@ -150,6 +150,7 @@ struct i40e_virtchnl_vsi_resource {
 #define I40E_VIRTCHNL_VF_OFFLOAD_FCOE		0x00000004
 #define I40E_VIRTCHNL_VF_OFFLOAD_RSS_AQ		0x00000008
 #define I40E_VIRTCHNL_VF_OFFLOAD_RSS_REG	0x00000010
+#define I40E_VIRTCHNL_VF_OFFLOAD_WB_ON_ITR	0x00000020
 #define I40E_VIRTCHNL_VF_OFFLOAD_VLAN		0x00010000
 #define I40E_VIRTCHNL_VF_OFFLOAD_RX_POLLING	0x00020000
 

drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -1203,6 +1203,10 @@ static int i40e_vc_get_vf_resources_msg(struct i40e_vf *vf, u8 *msg)
 	} else {
 		vfres->vf_offload_flags |= I40E_VIRTCHNL_VF_OFFLOAD_RSS_REG;
 	}
+
+	if (vf->driver_caps & I40E_VIRTCHNL_VF_OFFLOAD_RX_POLLING)
+		vfres->vf_offload_flags |= I40E_VIRTCHNL_VF_OFFLOAD_RX_POLLING;
+
 	vfres->num_vsis = num_vsis;
 	vfres->num_queue_pairs = vf->num_queue_pairs;
 	vfres->max_vectors = pf->hw.func_caps.num_msix_vectors_vf;

drivers/net/ethernet/intel/i40evf/i40e_virtchnl.h

@@ -150,6 +150,7 @@ struct i40e_virtchnl_vsi_resource {
 #define I40E_VIRTCHNL_VF_OFFLOAD_FCOE		0x00000004
 #define I40E_VIRTCHNL_VF_OFFLOAD_RSS_AQ		0x00000008
 #define I40E_VIRTCHNL_VF_OFFLOAD_RSS_REG	0x00000010
+#define I40E_VIRTCHNL_VF_OFFLOAD_WB_ON_ITR	0x00000020
 #define I40E_VIRTCHNL_VF_OFFLOAD_VLAN		0x00010000
 #define I40E_VIRTCHNL_VF_OFFLOAD_RX_POLLING	0x00020000
 

drivers/net/ethernet/intel/i40evf/i40evf_main.c

@@ -1123,6 +1123,8 @@ static int i40evf_alloc_queues(struct i40evf_adapter *adapter)
 		tx_ring->netdev = adapter->netdev;
 		tx_ring->dev = &adapter->pdev->dev;
 		tx_ring->count = adapter->tx_desc_count;
+		if (adapter->flags & I40E_FLAG_WB_ON_ITR_CAPABLE)
+			tx_ring->flags |= I40E_TXR_FLAGS_WB_ON_ITR;
 		adapter->tx_rings[i] = tx_ring;
 
 		rx_ring = &tx_ring[1];
@@ -2275,6 +2277,9 @@ static void i40evf_init_task(struct work_struct *work)
 	if (err)
 		goto err_sw_init;
 	i40evf_map_rings_to_vectors(adapter);
+	if (adapter->vf_res->vf_offload_flags &
+		    I40E_VIRTCHNL_VF_OFFLOAD_WB_ON_ITR)
+		adapter->flags |= I40EVF_FLAG_WB_ON_ITR_CAPABLE;
 	if (!RSS_AQ(adapter))
 		i40evf_configure_rss(adapter);
 	err = i40evf_request_misc_irq(adapter);

drivers/net/ethernet/intel/i40evf/i40evf_virtchnl.c

@@ -156,7 +156,8 @@ int i40evf_send_vf_config_msg(struct i40evf_adapter *adapter)
 	caps = I40E_VIRTCHNL_VF_OFFLOAD_L2 |
 	       I40E_VIRTCHNL_VF_OFFLOAD_RSS_AQ |
 	       I40E_VIRTCHNL_VF_OFFLOAD_RSS_REG |
-	       I40E_VIRTCHNL_VF_OFFLOAD_VLAN;
+	       I40E_VIRTCHNL_VF_OFFLOAD_VLAN |
+	       I40E_VIRTCHNL_VF_OFFLOAD_WB_ON_ITR;
 	adapter->current_op = I40E_VIRTCHNL_OP_GET_VF_RESOURCES;
 	adapter->aq_required &= ~I40EVF_FLAG_AQ_GET_CONFIG;
 	if (PF_IS_V11(adapter))