igc: Fix wrong timestamp latency numbers
authorVinicius Costa Gomes <vinicius.gomes@intel.com>
Tue, 18 Aug 2020 23:40:01 +0000 (16:40 -0700)
committerTony Nguyen <anthony.l.nguyen@intel.com>
Wed, 9 Sep 2020 22:06:24 +0000 (15:06 -0700)
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>
drivers/net/ethernet/intel/igc/igc.h

index 3070dfdb7eb4af48649fe4a646fc07ae93709ce9..2d566f3c827b57a0ed30c1c9eace1baf5b89e335 100644 (file)
@@ -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