From 5313eeccd2d7f486be4e5c7560e3e2be239ec8f7 Mon Sep 17 00:00:00 2001 From: Bernd Faust Date: Thu, 16 Feb 2017 19:42:07 +0100 Subject: e1000e: fix timing for 82579 Gigabit Ethernet controller After an upgrade to Linux kernel v4.x the hardware timestamps of the 82579 Gigabit Ethernet Controller are different than expected. The values that are being read are almost four times as big as before the kernel upgrade. The difference is that after the upgrade the driver sets the clock frequency to 25MHz, where before the upgrade it was set to 96MHz. Intel confirmed that the correct frequency for this network adapter is 96MHz. Signed-off-by: Bernd Faust Acked-by: Sasha Neftin Acked-by: Jacob Keller Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/net/ethernet') diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index e9af89ad039c..667fc45ce906 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -3511,6 +3511,12 @@ s32 e1000e_get_base_timinca(struct e1000_adapter *adapter, u32 *timinca) switch (hw->mac.type) { case e1000_pch2lan: + /* Stable 96MHz frequency */ + incperiod = INCPERIOD_96MHz; + incvalue = INCVALUE_96MHz; + shift = INCVALUE_SHIFT_96MHz; + adapter->cc.shift = shift + INCPERIOD_SHIFT_96MHz; + break; case e1000_pch_lpt: if (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI) { /* Stable 96MHz frequency */ -- cgit v1.2.3-59-g8ed1b