IB/hfi1: Convert PortXmitWait/PortVLXmitWait counters to flit times

HFI's counters SendWaitCnt and SendWaitVlCnt are in units
of TXE cycle time (at 805MHz). OPA counters PortXmitWait and
PortVLXmtWait are in units of flit times.
Convert the counter values to flit units using following
conversion formula:

PortXmitWait =
	SendWaitCnt * 2 * (4 /link_width) * (25 Gbps /link_speed)
PortVLXmitWait =
	SendWaitVLCnt * 2 * (4 /link_width) * (25 Gbps /link_speed)

At link up or downgrade events, the link width can change. To ensure
accurate counter calculations, sample the counters after the events,
during counter requests, and then aggregate the OPA counters.

Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Kamenee Arumugam <kamenee.arumugam@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 117 insertions, 10 deletions

diff --git a/drivers/infiniband/hw/hfi1/mad.c b/drivers/infiniband/hw/hfi1/mad.c
index 34547a48a445..e9962c65c68f 100644
--- a/drivers/infiniband/hw/hfi1/mad.c
+++ b/drivers/infiniband/hw/hfi1/mad.c
@@ -2649,6 +2649,79 @@ static void a0_portstatus(struct hfi1_pportdata *ppd,
 	}
 }
 
+/**
+ * tx_link_width - convert link width bitmask to integer
+ * value representing actual link width.
+ * @link_width: width of active link
+ * @return: return index of the bit set in link_width var
+ *
+ * The function convert and return the index of bit set
+ * that indicate the current link width.
+ */
+u16 tx_link_width(u16 link_width)
+{
+	int n = LINK_WIDTH_DEFAULT;
+	u16 tx_width = n;
+
+	while (link_width && n) {
+		if (link_width & (1 << (n - 1))) {
+			tx_width = n;
+			break;
+		}
+		n--;
+	}
+
+	return tx_width;
+}
+
+/**
+ * get_xmit_wait_counters - Convert HFI 's SendWaitCnt/SendWaitVlCnt
+ * counter in unit of TXE cycle times to flit times.
+ * @ppd: info of physical Hfi port
+ * @link_width: width of active link
+ * @link_speed: speed of active link
+ * @vl: represent VL0-VL7, VL15 for PortVLXmitWait counters request
+ * and if vl value is C_VL_COUNT, it represent SendWaitCnt
+ * counter request
+ * @return: return SendWaitCnt/SendWaitVlCnt counter value per vl.
+ *
+ * Convert SendWaitCnt/SendWaitVlCnt counter from TXE cycle times to
+ * flit times. Call this function to samples these counters. This
+ * function will calculate for previous state transition and update
+ * current state at end of function using ppd->prev_link_width and
+ * ppd->port_vl_xmit_wait_last to port_vl_xmit_wait_curr and link_width.
+ */
+u64 get_xmit_wait_counters(struct hfi1_pportdata *ppd,
+			   u16 link_width, u16 link_speed, int vl)
+{
+	u64 port_vl_xmit_wait_curr;
+	u64 delta_vl_xmit_wait;
+	u64 xmit_wait_val;
+
+	if (vl > C_VL_COUNT)
+		return  0;
+	if (vl < C_VL_COUNT)
+		port_vl_xmit_wait_curr =
+			read_port_cntr(ppd, C_TX_WAIT_VL, vl);
+	else
+		port_vl_xmit_wait_curr =
+			read_port_cntr(ppd, C_TX_WAIT, CNTR_INVALID_VL);
+
+	xmit_wait_val =
+		port_vl_xmit_wait_curr -
+		ppd->port_vl_xmit_wait_last[vl];
+	delta_vl_xmit_wait =
+		convert_xmit_counter(xmit_wait_val,
+				     ppd->prev_link_width,
+				     link_speed);
+
+	ppd->vl_xmit_flit_cnt[vl] += delta_vl_xmit_wait;
+	ppd->port_vl_xmit_wait_last[vl] = port_vl_xmit_wait_curr;
+	ppd->prev_link_width = link_width;
+
+	return ppd->vl_xmit_flit_cnt[vl];
+}
+
 static int pma_get_opa_portstatus(struct opa_pma_mad *pmp,
 				  struct ib_device *ibdev,
 				  u8 port, u32 *resp_len)
@@ -2668,6 +2741,8 @@ static int pma_get_opa_portstatus(struct opa_pma_mad *pmp,
 	struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
 	int vfi;
 	u64 tmp, tmp2;
+	u16 link_width;
+	u16 link_speed;
 
 	response_data_size = sizeof(struct opa_port_status_rsp) +
 				num_vls * sizeof(struct _vls_pctrs);
@@ -2711,8 +2786,16 @@ static int pma_get_opa_portstatus(struct opa_pma_mad *pmp,
 	rsp->port_multicast_rcv_pkts =
 		cpu_to_be64(read_dev_cntr(dd, C_DC_MC_RCV_PKTS,
 					  CNTR_INVALID_VL));
+	/*
+	 * Convert PortXmitWait counter from TXE cycle times
+	 * to flit times.
+	 */
+	link_width =
+		tx_link_width(ppd->link_width_downgrade_tx_active);
+	link_speed = get_link_speed(ppd->link_speed_active);
 	rsp->port_xmit_wait =
-		cpu_to_be64(read_port_cntr(ppd, C_TX_WAIT, CNTR_INVALID_VL));
+		cpu_to_be64(get_xmit_wait_counters(ppd, link_width,
+						   link_speed, C_VL_COUNT));
 	rsp->port_rcv_fecn =
 		cpu_to_be64(read_dev_cntr(dd, C_DC_RCV_FCN, CNTR_INVALID_VL));
 	rsp->port_rcv_becn =
@@ -2777,10 +2860,14 @@ static int pma_get_opa_portstatus(struct opa_pma_mad *pmp,
 		rsp->vls[vfi].port_vl_xmit_pkts =
 			cpu_to_be64(read_port_cntr(ppd, C_TX_PKT_VL,
 						   idx_from_vl(vl)));
-
+		/*
+		 * Convert PortVlXmitWait counter from TXE cycle
+		 * times to flit times.
+		 */
 		rsp->vls[vfi].port_vl_xmit_wait =
-			cpu_to_be64(read_port_cntr(ppd, C_TX_WAIT_VL,
-						   idx_from_vl(vl)));
+			cpu_to_be64(get_xmit_wait_counters(ppd, link_width,
+							   link_speed,
+							   idx_from_vl(vl)));
 
 		rsp->vls[vfi].port_vl_rcv_fecn =
 			cpu_to_be64(read_dev_cntr(dd, C_DC_RCV_FCN_VL,
@@ -2910,6 +2997,8 @@ static int pma_get_opa_datacounters(struct opa_pma_mad *pmp,
 	unsigned long vl;
 	u32 vl_select_mask;
 	int vfi;
+	u16 link_width;
+	u16 link_speed;
 
 	num_ports = be32_to_cpu(pmp->mad_hdr.attr_mod) >> 24;
 	num_vls = hweight32(be32_to_cpu(req->vl_select_mask));
@@ -2959,8 +3048,16 @@ static int pma_get_opa_datacounters(struct opa_pma_mad *pmp,
 	rsp->link_quality_indicator = cpu_to_be32((u32)lq);
 	pma_get_opa_port_dctrs(ibdev, rsp);
 
+	/*
+	 * Convert PortXmitWait counter from TXE
+	 * cycle times to flit times.
+	 */
+	link_width =
+		tx_link_width(ppd->link_width_downgrade_tx_active);
+	link_speed = get_link_speed(ppd->link_speed_active);
 	rsp->port_xmit_wait =
-		cpu_to_be64(read_port_cntr(ppd, C_TX_WAIT, CNTR_INVALID_VL));
+		cpu_to_be64(get_xmit_wait_counters(ppd, link_width,
+						   link_speed, C_VL_COUNT));
 	rsp->port_rcv_fecn =
 		cpu_to_be64(read_dev_cntr(dd, C_DC_RCV_FCN, CNTR_INVALID_VL));
 	rsp->port_rcv_becn =
@@ -2996,9 +3093,14 @@ static int pma_get_opa_datacounters(struct opa_pma_mad *pmp,
 			cpu_to_be64(read_dev_cntr(dd, C_DC_RX_PKT_VL,
 						  idx_from_vl(vl)));
 
+		/*
+		 * Convert PortVlXmitWait counter from TXE
+		 * cycle times to flit times.
+		 */
 		rsp->vls[vfi].port_vl_xmit_wait =
-			cpu_to_be64(read_port_cntr(ppd, C_TX_WAIT_VL,
-						   idx_from_vl(vl)));
+			cpu_to_be64(get_xmit_wait_counters(ppd, link_width,
+							   link_speed,
+							   idx_from_vl(vl)));
 
 		rsp->vls[vfi].port_vl_rcv_fecn =
 			cpu_to_be64(read_dev_cntr(dd, C_DC_RCV_FCN_VL,
@@ -3416,9 +3518,11 @@ static int pma_set_opa_portstatus(struct opa_pma_mad *pmp,
 	if (counter_select & CS_PORT_MCAST_RCV_PKTS)
 		write_dev_cntr(dd, C_DC_MC_RCV_PKTS, CNTR_INVALID_VL, 0);
 
-	if (counter_select & CS_PORT_XMIT_WAIT)
+	if (counter_select & CS_PORT_XMIT_WAIT) {
 		write_port_cntr(ppd, C_TX_WAIT, CNTR_INVALID_VL, 0);
-
+		ppd->port_vl_xmit_wait_last[C_VL_COUNT] = 0;
+		ppd->vl_xmit_flit_cnt[C_VL_COUNT] = 0;
+	}
 	/* ignore cs_sw_portCongestion for HFIs */
 
 	if (counter_select & CS_PORT_RCV_FECN)
@@ -3491,8 +3595,11 @@ static int pma_set_opa_portstatus(struct opa_pma_mad *pmp,
 		if (counter_select & CS_PORT_RCV_PKTS)
 			write_dev_cntr(dd, C_DC_RX_PKT_VL, idx_from_vl(vl), 0);
 
-		if (counter_select & CS_PORT_XMIT_WAIT)
+		if (counter_select & CS_PORT_XMIT_WAIT) {
 			write_port_cntr(ppd, C_TX_WAIT_VL, idx_from_vl(vl), 0);
+			ppd->port_vl_xmit_wait_last[idx_from_vl(vl)] = 0;
+			ppd->vl_xmit_flit_cnt[idx_from_vl(vl)] = 0;
+		}
 
 		/* sw_port_vl_congestion is 0 for HFIs */
 		if (counter_select & CS_PORT_RCV_FECN)