Commit bf03085f authored by Matthew Vick's avatar Matthew Vick Committed by Jeff Kirsher
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e1000e: Guarantee descriptor writeback flush success. 



In rare circumstances, a descriptor writeback flush may not work if it
arrives on a specific clock cycle as a writeback request is going out.

Signed-off-by: default avatarMatthew Vick <matthew.vick@intel.com>
Tested-by: default avatarAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent bb9e44d0

drivers/net/ethernet/intel/e1000e/netdev.c

+17 −0
Original line number Diff line number Diff line
@@ -1059,6 +1059,13 @@ static void e1000_print_hw_hang(struct work_struct *work) 
		ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);

		/* execute the writes immediately */

		e1e_flush();

		/*

		 * Due to rare timing issues, write to TIDV again to ensure

		 * the write is successful

		 */

		ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);

		/* execute the writes immediately */

		e1e_flush();

		adapter->tx_hang_recheck = true;

		return;

	}
@@ -3616,6 +3623,16 @@ static void e1000e_flush_descriptors(struct e1000_adapter *adapter) 


	/* execute the writes immediately */

	e1e_flush();



	/*

	 * due to rare timing issues, write to TIDV/RDTR again to ensure the

	 * write is successful

	 */

	ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);

	ew32(RDTR, adapter->rx_int_delay | E1000_RDTR_FPD);



	/* execute the writes immediately */

	e1e_flush();

}



static void e1000e_update_stats(struct e1000_adapter *adapter);