net: thunderx: Reset RXQ HW stats when interface is brought down

When SQ/TXQ is reclaimed i.e reset it's stats also automatically reset
by HW. This is not the case with RQ. Also VF doesn't have write access
to statistics counter registers. Hence a new Mbox msg is introduced which
supports resetting RQ, SQ and full Qset stats. Currently only RQ stats
are being reset using this mbox message.
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cavium/thunder/nic.h

@@ -347,6 +347,7 @@ struct nicvf {
 #define	NIC_MBOX_MSG_PNICVF_PTR		0x14	/* Get primary qset nicvf ptr */
 #define	NIC_MBOX_MSG_SNICVF_PTR		0x15	/* Send sqet nicvf ptr to PVF */
 #define	NIC_MBOX_MSG_LOOPBACK		0x16	/* Set interface in loopback */
+#define	NIC_MBOX_MSG_RESET_STAT_COUNTER 0x17	/* Reset statistics counters */
 #define	NIC_MBOX_MSG_CFG_DONE		0xF0	/* VF configuration done */
 #define	NIC_MBOX_MSG_SHUTDOWN		0xF1	/* VF is being shutdown */
 
@@ -463,6 +464,31 @@ struct set_loopback {
 	bool  enable;
 };
 
+/* Reset statistics counters */
+struct reset_stat_cfg {
+	u8    msg;
+	/* Bitmap to select NIC_PF_VNIC(vf_id)_RX_STAT(0..13) */
+	u16   rx_stat_mask;
+	/* Bitmap to select NIC_PF_VNIC(vf_id)_TX_STAT(0..4) */
+	u8    tx_stat_mask;
+	/* Bitmap to select NIC_PF_QS(0..127)_RQ(0..7)_STAT(0..1)
+	 * bit14, bit15 NIC_PF_QS(vf_id)_RQ7_STAT(0..1)
+	 * bit12, bit13 NIC_PF_QS(vf_id)_RQ6_STAT(0..1)
+	 * ..
+	 * bit2, bit3 NIC_PF_QS(vf_id)_RQ1_STAT(0..1)
+	 * bit0, bit1 NIC_PF_QS(vf_id)_RQ0_STAT(0..1)
+	 */
+	u16   rq_stat_mask;
+	/* Bitmap to select NIC_PF_QS(0..127)_SQ(0..7)_STAT(0..1)
+	 * bit14, bit15 NIC_PF_QS(vf_id)_SQ7_STAT(0..1)
+	 * bit12, bit13 NIC_PF_QS(vf_id)_SQ6_STAT(0..1)
+	 * ..
+	 * bit2, bit3 NIC_PF_QS(vf_id)_SQ1_STAT(0..1)
+	 * bit0, bit1 NIC_PF_QS(vf_id)_SQ0_STAT(0..1)
+	 */
+	u16   sq_stat_mask;
+};
+
 /* 128 bit shared memory between PF and each VF */
 union nic_mbx {
 	struct { u8 msg; }	msg;
@@ -480,6 +506,7 @@ union nic_mbx {
 	struct sqs_alloc        sqs_alloc;
 	struct nicvf_ptr	nicvf;
 	struct set_loopback	lbk;
+	struct reset_stat_cfg	reset_stat;
 };
 
 #define NIC_NODE_ID_MASK	0x03

drivers/net/ethernet/cavium/thunder/nic_main.c

@@ -793,6 +793,48 @@ static int nic_config_loopback(struct nicpf *nic, struct set_loopback *lbk)
 	return 0;
 }
 
+/* Reset statistics counters */
+static int nic_reset_stat_counters(struct nicpf *nic,
+				   int vf, struct reset_stat_cfg *cfg)
+{
+	int i, stat, qnum;
+	u64 reg_addr;
+
+	for (i = 0; i < RX_STATS_ENUM_LAST; i++) {
+		if (cfg->rx_stat_mask & BIT(i)) {
+			reg_addr = NIC_PF_VNIC_0_127_RX_STAT_0_13 |
+				   (vf << NIC_QS_ID_SHIFT) |
+				   (i << 3);
+			nic_reg_write(nic, reg_addr, 0);
+		}
+	}
+
+	for (i = 0; i < TX_STATS_ENUM_LAST; i++) {
+		if (cfg->tx_stat_mask & BIT(i)) {
+			reg_addr = NIC_PF_VNIC_0_127_TX_STAT_0_4 |
+				   (vf << NIC_QS_ID_SHIFT) |
+				   (i << 3);
+			nic_reg_write(nic, reg_addr, 0);
+		}
+	}
+
+	for (i = 0; i <= 15; i++) {
+		qnum = i >> 1;
+		stat = i & 1 ? 1 : 0;
+		reg_addr = (vf << NIC_QS_ID_SHIFT) |
+			   (qnum << NIC_Q_NUM_SHIFT) | (stat << 3);
+		if (cfg->rq_stat_mask & BIT(i)) {
+			reg_addr |= NIC_PF_QSET_0_127_RQ_0_7_STAT_0_1;
+			nic_reg_write(nic, reg_addr, 0);
+		}
+		if (cfg->sq_stat_mask & BIT(i)) {
+			reg_addr |= NIC_PF_QSET_0_127_SQ_0_7_STAT_0_1;
+			nic_reg_write(nic, reg_addr, 0);
+		}
+	}
+	return 0;
+}
+
 static void nic_enable_vf(struct nicpf *nic, int vf, bool enable)
 {
 	int bgx, lmac;
@@ -942,6 +984,9 @@ static void nic_handle_mbx_intr(struct nicpf *nic, int vf)
 	case NIC_MBOX_MSG_LOOPBACK:
 		ret = nic_config_loopback(nic, &mbx.lbk);
 		break;
+	case NIC_MBOX_MSG_RESET_STAT_COUNTER:
+		ret = nic_reset_stat_counters(nic, vf, &mbx.reset_stat);
+		break;
 	default:
 		dev_err(&nic->pdev->dev,
 			"Invalid msg from VF%d, msg 0x%x\n", vf, mbx.msg.msg);

drivers/net/ethernet/cavium/thunder/nicvf_queues.c

@@ -479,6 +479,16 @@ void nicvf_config_vlan_stripping(struct nicvf *nic, netdev_features_t features)
 					      NIC_QSET_RQ_GEN_CFG, 0, rq_cfg);
 }
 
+static void nicvf_reset_rcv_queue_stats(struct nicvf *nic)
+{
+	union nic_mbx mbx = {};
+
+	/* Reset all RXQ's stats */
+	mbx.reset_stat.msg = NIC_MBOX_MSG_RESET_STAT_COUNTER;
+	mbx.reset_stat.rq_stat_mask = 0xFFFF;
+	nicvf_send_msg_to_pf(nic, &mbx);
+}
+
 /* Configures receive queue */
 static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
 				   int qidx, bool enable)
@@ -812,6 +822,11 @@ int nicvf_config_data_transfer(struct nicvf *nic, bool enable)
 		nicvf_free_resources(nic);
 	}
 
+	/* Reset RXQ's stats.
+	 * SQ's stats will get reset automatically once SQ is reset.
+	 */
+	nicvf_reset_rcv_queue_stats(nic);
+
 	return 0;
 }