RDMA/ocrdma: Use VID 0 if PFC is enabled and vlan is not configured

If the adapter ports are in PFC mode and VLAN is not configured,
use vlan tag 0 for RoCE traffic. Also, log an advisory message
in system logs.
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@avagotech.com>
Signed-off-by: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Selvin Xavier <selvin.xavier@avagotech.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/ocrdma/ocrdma_ah.c

@@ -56,7 +56,13 @@ static inline int set_av_attr(struct ocrdma_dev *dev, struct ocrdma_ah *ah,
 	vlan_tag = attr->vlan_id;
 	if (!vlan_tag || (vlan_tag > 0xFFF))
 		vlan_tag = dev->pvid;
-	if (vlan_tag && (vlan_tag < 0x1000)) {
+	if (vlan_tag || dev->pfc_state) {
+		if (!vlan_tag) {
+			pr_err("ocrdma%d:Using VLAN with PFC is recommended\n",
+				dev->id);
+			pr_err("ocrdma%d:Using VLAN 0 for this connection\n",
+				dev->id);
+		}
 		eth.eth_type = cpu_to_be16(0x8100);
 		eth.roce_eth_type = cpu_to_be16(OCRDMA_ROCE_ETH_TYPE);
 		vlan_tag |= (dev->sl & 0x07) << OCRDMA_VID_PCP_SHIFT;

drivers/infiniband/hw/ocrdma/ocrdma_hw.c

@@ -2434,7 +2434,7 @@ static int ocrdma_set_av_params(struct ocrdma_qp *qp,
 	int status;
 	struct ib_ah_attr *ah_attr = &attrs->ah_attr;
 	union ib_gid sgid, zgid;
-	u32 vlan_id;
+	u32 vlan_id = 0xFFFF;
 	u8 mac_addr[6];
 	struct ocrdma_dev *dev = get_ocrdma_dev(qp->ibqp.device);
 
@@ -2474,12 +2474,22 @@ static int ocrdma_set_av_params(struct ocrdma_qp *qp,
 	cmd->params.vlan_dmac_b4_to_b5 = mac_addr[4] | (mac_addr[5] << 8);
 	if (attr_mask & IB_QP_VID) {
 		vlan_id = attrs->vlan_id;
+	} else if (dev->pfc_state) {
+		vlan_id = 0;
+		pr_err("ocrdma%d:Using VLAN with PFC is recommended\n",
+			dev->id);
+		pr_err("ocrdma%d:Using VLAN 0 for this connection\n",
+			dev->id);
+	}
+
+	if (vlan_id < 0x1000) {
 		cmd->params.vlan_dmac_b4_to_b5 |=
 		    vlan_id << OCRDMA_QP_PARAMS_VLAN_SHIFT;
 		cmd->flags |= OCRDMA_QP_PARA_VLAN_EN_VALID;
 		cmd->params.rnt_rc_sl_fl |=
 			(dev->sl & 0x07) << OCRDMA_QP_PARAMS_SL_SHIFT;
 	}
+
 	return 0;
 }