[PATCH] e1000e: fix timing for 82579 Gigabit Ethernet controller
From: Bernd Faust <hidden>
Date: 2017-02-16 18:42:22
Also in:
intel-wired-lan, lkml
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted> --- drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 7017281..8b7113d 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 */