svn commit: r318839 - in stable/11/sys/dev/cxgbe: . common

[Navdeep Parhar]

Author: np
Date: Thu May 25 00:16:01 2017
New Revision: 318839
URL: https://svnweb.freebsd.org/changeset/base/318839

Log:
  MFC r316971:
  
  cxgbe: Add a tunable to configure the SGE time scaler, which is
  available starting with T6.  The values in the timer holdoff registers
  are multiplied by the scaling factor before use.
  
  dev.<nexus>.<n>.holdoff_timers shows the final values of the
  timers in microseconds.
  
  Sponsored by:	Chelsio Communications

Modified:
  stable/11/sys/dev/cxgbe/common/common.h
  stable/11/sys/dev/cxgbe/common/t4_hw.c
  stable/11/sys/dev/cxgbe/t4_sge.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/dev/cxgbe/common/common.h
==============================================================================
--- stable/11/sys/dev/cxgbe/common/common.h	Wed May 24 23:08:45 2017	(r318838)
+++ stable/11/sys/dev/cxgbe/common/common.h	Thu May 25 00:16:01 2017	(r318839)
@@ -210,7 +210,7 @@ struct tp_rdma_stats {
 };
 
 struct sge_params {
-	int timer_val[SGE_NTIMERS];
+	int timer_val[SGE_NTIMERS];	/* final, scaled values */
 	int counter_val[SGE_NCOUNTERS];
 	int fl_starve_threshold;
 	int fl_starve_threshold2;

Modified: stable/11/sys/dev/cxgbe/common/t4_hw.c
==============================================================================
--- stable/11/sys/dev/cxgbe/common/t4_hw.c	Wed May 24 23:08:45 2017	(r318838)
+++ stable/11/sys/dev/cxgbe/common/t4_hw.c	Thu May 25 00:16:01 2017	(r318839)
@@ -7907,7 +7907,7 @@ int t4_init_sge_params(struct adapter *a
 {
 	u32 r;
 	struct sge_params *sp = &adapter->params.sge;
-	unsigned i;
+	unsigned i, tscale = 1;
 
 	r = t4_read_reg(adapter, A_SGE_INGRESS_RX_THRESHOLD);
 	sp->counter_val[0] = G_THRESHOLD_0(r);
@@ -7915,15 +7915,24 @@ int t4_init_sge_params(struct adapter *a
 	sp->counter_val[2] = G_THRESHOLD_2(r);
 	sp->counter_val[3] = G_THRESHOLD_3(r);
 
+	if (chip_id(adapter) >= CHELSIO_T6) {
+		r = t4_read_reg(adapter, A_SGE_ITP_CONTROL);
+		tscale = G_TSCALE(r);
+		if (tscale == 0)
+			tscale = 1;
+		else
+			tscale += 2;
+	}
+
 	r = t4_read_reg(adapter, A_SGE_TIMER_VALUE_0_AND_1);
-	sp->timer_val[0] = core_ticks_to_us(adapter, G_TIMERVALUE0(r));
-	sp->timer_val[1] = core_ticks_to_us(adapter, G_TIMERVALUE1(r));
+	sp->timer_val[0] = core_ticks_to_us(adapter, G_TIMERVALUE0(r)) * tscale;
+	sp->timer_val[1] = core_ticks_to_us(adapter, G_TIMERVALUE1(r)) * tscale;
 	r = t4_read_reg(adapter, A_SGE_TIMER_VALUE_2_AND_3);
-	sp->timer_val[2] = core_ticks_to_us(adapter, G_TIMERVALUE2(r));
-	sp->timer_val[3] = core_ticks_to_us(adapter, G_TIMERVALUE3(r));
+	sp->timer_val[2] = core_ticks_to_us(adapter, G_TIMERVALUE2(r)) * tscale;
+	sp->timer_val[3] = core_ticks_to_us(adapter, G_TIMERVALUE3(r)) * tscale;
 	r = t4_read_reg(adapter, A_SGE_TIMER_VALUE_4_AND_5);
-	sp->timer_val[4] = core_ticks_to_us(adapter, G_TIMERVALUE4(r));
-	sp->timer_val[5] = core_ticks_to_us(adapter, G_TIMERVALUE5(r));
+	sp->timer_val[4] = core_ticks_to_us(adapter, G_TIMERVALUE4(r)) * tscale;
+	sp->timer_val[5] = core_ticks_to_us(adapter, G_TIMERVALUE5(r)) * tscale;
 
 	r = t4_read_reg(adapter, A_SGE_CONM_CTRL);
 	sp->fl_starve_threshold = G_EGRTHRESHOLD(r) * 2 + 1;

Modified: stable/11/sys/dev/cxgbe/t4_sge.c
==============================================================================
--- stable/11/sys/dev/cxgbe/t4_sge.c	Wed May 24 23:08:45 2017	(r318838)
+++ stable/11/sys/dev/cxgbe/t4_sge.c	Thu May 25 00:16:01 2017	(r318839)
@@ -150,6 +150,13 @@ TUNABLE_INT("hw.cxgbe.largest_rx_cluster
 static int safest_rx_cluster = PAGE_SIZE;
 TUNABLE_INT("hw.cxgbe.safest_rx_cluster", &safest_rx_cluster);
 
+/*
+ * The interrupt holdoff timers are multiplied by this value on T6+.
+ * 1 and 3-17 (both inclusive) are legal values.
+ */
+static int tscale = 1;
+TUNABLE_INT("hw.cxgbe.tscale", &tscale);
+
 struct txpkts {
 	u_int wr_type;		/* type 0 or type 1 */
 	u_int npkt;		/* # of packets in this work request */
@@ -391,6 +398,12 @@ t4_sge_modload(void)
 		cong_drop = 0;
 	}
 
+	if (tscale != 1 && (tscale < 3 || tscale > 17)) {
+		printf("Invalid hw.cxgbe.tscale value (%d),"
+		    " using 1 instead.\n", tscale);
+		tscale = 1;
+	}
+
 	extfree_refs = counter_u64_alloc(M_WAITOK);
 	extfree_rels = counter_u64_alloc(M_WAITOK);
 	counter_u64_zero(extfree_refs);
@@ -583,6 +596,15 @@ t4_tweak_chip_settings(struct adapter *s
 	    V_TIMERVALUE5(us_to_core_ticks(sc, intr_timer[5]));
 	t4_write_reg(sc, A_SGE_TIMER_VALUE_4_AND_5, v);
 
+	if (chip_id(sc) >= CHELSIO_T6) {
+		m = V_TSCALE(M_TSCALE);
+		if (tscale == 1)
+			v = 0;
+		else
+			v = V_TSCALE(tscale - 2);
+		t4_set_reg_field(sc, A_SGE_ITP_CONTROL, m, v);
+	}
+
 	/* 4K, 16K, 64K, 256K DDP "page sizes" */
 	v = V_HPZ0(0) | V_HPZ1(2) | V_HPZ2(4) | V_HPZ3(6);
 	t4_write_reg(sc, A_ULP_RX_TDDP_PSZ, v);