ixgbe: allow ixgbe_ptp_reset to maintain current hwtstamp config

Rather than clearing the hwtstamp configuration, we should use the known
configuration requested by the user and call the function which has now
been separated from the ioctl. This means that after a reset, the
timestamp mode will be maintained rather than lost. We still can't
maintain the clock value, however.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c

@@ -812,9 +812,13 @@ void ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter *adapter)
  * ixgbe_ptp_reset
  * @adapter: the ixgbe private board structure
  *
- * When the MAC resets, all timesync features are reset. This function should be
- * called to re-enable the PTP clock structure. It will re-init the timecounter
- * structure based on the kernel time as well as setup the cycle counter data.
+ * When the MAC resets, all the hardware bits for timesync are reset. This
+ * function is used to re-enable the device for PTP based on current settings.
+ * We do lose the current clock time, so just reset the cyclecounter to the
+ * system real clock time.
+ *
+ * This function will maintain hwtstamp_config settings, and resets the SDP
+ * output if it was enabled.
  */
 void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
 {
@@ -826,8 +830,8 @@ void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
 	IXGBE_WRITE_REG(hw, IXGBE_SYSTIMH, 0x00000000);
 	IXGBE_WRITE_FLUSH(hw);
 
-	/* Reset the saved tstamp_config */
-	memset(&adapter->tstamp_config, 0, sizeof(adapter->tstamp_config));
+	/* reset the hardware timestamping mode */
+	ixgbe_ptp_set_timestamp_mode(adapter, &adapter->tstamp_config);
 
 	ixgbe_ptp_start_cyclecounter(adapter);
 
@@ -907,6 +911,8 @@ void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
 	} else
 		e_dev_info("registered PHC device on %s\n", netdev->name);
 
+	adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
+	adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
 	ixgbe_ptp_reset(adapter);
 
 	/* enter the IXGBE_PTP_RUNNING state */