igc: Fix wrong timestamp latency numbers

The previous timestamping latency numbers were obtained by
interpolating the i210 numbers with the i225 crystal clock value. That
calculation was wrong.

Use the correct values from real measurements.

Fixes: 81b055205e8b ("igc: Add support for RX timestamping")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index 3070dfd..2d566f3 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -299,18 +299,14 @@ extern char igc_driver_name[];
 #define IGC_RX_HDR_LEN                 IGC_RXBUFFER_256
 
 /* Transmit and receive latency (for PTP timestamps) */
-/* FIXME: These values were estimated using the ones that i225 has as
- * basis, they seem to provide good numbers with ptp4l/phc2sys, but we
- * need to confirm them.
- */
-#define IGC_I225_TX_LATENCY_10         9542
-#define IGC_I225_TX_LATENCY_100                1024
-#define IGC_I225_TX_LATENCY_1000       178
-#define IGC_I225_TX_LATENCY_2500       64
-#define IGC_I225_RX_LATENCY_10         20662
-#define IGC_I225_RX_LATENCY_100                2213
-#define IGC_I225_RX_LATENCY_1000       448
-#define IGC_I225_RX_LATENCY_2500       160
+#define IGC_I225_TX_LATENCY_10         240
+#define IGC_I225_TX_LATENCY_100                58
+#define IGC_I225_TX_LATENCY_1000       80
+#define IGC_I225_TX_LATENCY_2500       1325
+#define IGC_I225_RX_LATENCY_10         6450
+#define IGC_I225_RX_LATENCY_100                185
+#define IGC_I225_RX_LATENCY_1000       300
+#define IGC_I225_RX_LATENCY_2500       1485
 
 /* RX and TX descriptor control thresholds.
  * PTHRESH - MAC will consider prefetch if it has fewer than this number of