igb: support PEROUT on 82580/i354/i350

Support for the PEROUT PTP pin function on 82580/i354/i350 based adapters.
Because the time registers of these adapters do not have the nice split in
second rollovers as the i210 has, the implementation is slightly more
complex compared to the i210 implementation.

Signed-off-by: Ruud Bos <kernel.hbk@gmail.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 57 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 6d1d65f4a528..bf8fb4347bc5 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -6750,8 +6750,62 @@ static void igb_perout(struct igb_adapter *adapter, int tsintr_tt)
 		return;
 
 	spin_lock(&adapter->tmreg_lock);
-	ts = timespec64_add(adapter->perout[pin].start,
-			    adapter->perout[pin].period);
+
+	if (hw->mac.type == e1000_82580 ||
+	    hw->mac.type == e1000_i354 ||
+	    hw->mac.type == e1000_i350) {
+		s64 ns = timespec64_to_ns(&adapter->perout[pin].period);
+		u32 systiml, systimh, level_mask, level, rem;
+		u64 systim, now;
+
+		/* read systim registers in sequence */
+		rd32(E1000_SYSTIMR);
+		systiml = rd32(E1000_SYSTIML);
+		systimh = rd32(E1000_SYSTIMH);
+		systim = (((u64)(systimh & 0xFF)) << 32) | ((u64)systiml);
+		now = timecounter_cyc2time(&adapter->tc, systim);
+
+		if (pin < 2) {
+			level_mask = (tsintr_tt == 1) ? 0x80000 : 0x40000;
+			level = (rd32(E1000_CTRL) & level_mask) ? 1 : 0;
+		} else {
+			level_mask = (tsintr_tt == 1) ? 0x80 : 0x40;
+			level = (rd32(E1000_CTRL_EXT) & level_mask) ? 1 : 0;
+		}
+
+		div_u64_rem(now, ns, &rem);
+		systim = systim + (ns - rem);
+
+		/* synchronize pin level with rising/falling edges */
+		div_u64_rem(now, ns << 1, &rem);
+		if (rem < ns) {
+			/* first half of period */
+			if (level == 0) {
+				/* output is already low, skip this period */
+				systim += ns;
+				pr_notice("igb: periodic output on %s missed falling edge\n",
+					  adapter->sdp_config[pin].name);
+			}
+		} else {
+			/* second half of period */
+			if (level == 1) {
+				/* output is already high, skip this period */
+				systim += ns;
+				pr_notice("igb: periodic output on %s missed rising edge\n",
+					  adapter->sdp_config[pin].name);
+			}
+		}
+
+		/* for this chip family tv_sec is the upper part of the binary value,
+		 * so not seconds
+		 */
+		ts.tv_nsec = (u32)systim;
+		ts.tv_sec  = ((u32)(systim >> 32)) & 0xFF;
+	} else {
+		ts = timespec64_add(adapter->perout[pin].start,
+				    adapter->perout[pin].period);
+	}
+
 	/* u32 conversion of tv_sec is safe until y2106 */
 	wr32((tsintr_tt == 1) ? E1000_TRGTTIML1 : E1000_TRGTTIML0, ts.tv_nsec);
 	wr32((tsintr_tt == 1) ? E1000_TRGTTIMH1 : E1000_TRGTTIMH0, (u32)ts.tv_sec);
@@ -6759,6 +6813,7 @@ static void igb_perout(struct igb_adapter *adapter, int tsintr_tt)
 	tsauxc |= TSAUXC_EN_TT0;
 	wr32(E1000_TSAUXC, tsauxc);
 	adapter->perout[pin].start = ts;
+
 	spin_unlock(&adapter->tmreg_lock);
 }