lkml.org 
[lkml]   [2018]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL for 3.18 22/53] e1000e: fix timing for 82579 Gigabit Ethernet controller
Date
From: Bernd Faust <berndfaust@gmail.com>

[ Upstream commit 5313eeccd2d7f486be4e5c7560e3e2be239ec8f7 ]

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 <berndfaust@gmail.com>
Acked-by: Sasha Neftin <sasha.neftin@intel.com>
Acked-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
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 081dad4e0178..3df8366a8356 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -3507,6 +3507,12 @@ 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:
/* On I217, the clock frequency is 25MHz or 96MHz as
* indicated by the System Clock Frequency Indication
--
2.14.1
\
 
 \ /
  Last update: 2018-03-08 06:12    [W:0.225 / U:0.516 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site