This is a note to let you know that I've just added the patch titled

igb: reset the PHY before reading the PHY ID

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: igb-reset-the-phy-before-reading-the-phy-id.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Sun Nov 19 11:32:28 CET 2017

From: Aaron Sierra asierra@xes-inc.com Date: Tue, 29 Nov 2016 10:03:56 -0600 Subject: igb: reset the PHY before reading the PHY ID

From: Aaron Sierra asierra@xes-inc.com

[ Upstream commit 182785335447957409282ca745aa5bc3968facee ]

Several people have reported firmware leaving the I210/I211 PHY's page select register set to something other than the default of zero. This causes the first accesses, PHY_IDx register reads, to access something else, resulting in device probe failure:

igb: Intel(R) Gigabit Ethernet Network Driver - version 5.4.0-k igb: Copyright (c) 2007-2014 Intel Corporation. igb: probe of 0000:01:00.0 failed with error -2

This problem began for them after a previous patch I submitted was applied:

commit 2a3cdead8b408351fa1e3079b220fa331480ffbc Author: Aaron Sierra asierra@xes-inc.com Date: Tue Nov 3 12:37:09 2015 -0600

igb: Remove GS40G specific defines/functions

I personally experienced this problem after attempting to PXE boot from I210 devices using this firmware:

Intel(R) Boot Agent GE v1.5.78 Copyright (C) 1997-2014, Intel Corporation

Resetting the PHY before reading from it, ensures the page select register is in its default state and doesn't make assumptions about the PHY's register set before the PHY has been probed.

Cc: Matwey V. Kornilov matwey@sai.msu.ru Cc: Chris Arges carges@vectranetworks.com Cc: Jochen Henneberg jh@henneberg-systemdesign.com Signed-off-by: Aaron Sierra asierra@xes-inc.com Tested-by: Matwey V. Kornilov matwey@sai.msu.ru Tested-by: Chris J Arges christopherarges@gmail.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@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/intel/igb/e1000_82575.c | 11 +++++++++++ 1 file changed, 11 insertions(+)

--- a/drivers/net/ethernet/intel/igb/e1000_82575.c +++ b/drivers/net/ethernet/intel/igb/e1000_82575.c @@ -245,6 +245,17 @@ static s32 igb_init_phy_params_82575(str hw->bus.func = (rd32(E1000_STATUS) & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;

+ /* Make sure the PHY is in a good state. Several people have reported + * firmware leaving the PHY's page select register set to something + * other than the default of zero, which causes the PHY ID read to + * access something other than the intended register. + */ + ret_val = hw->phy.ops.reset(hw); + if (ret_val) { + hw_dbg("Error resetting the PHY.\n"); + goto out; + } + /* Set phy->phy_addr and phy->id. */ igb_write_phy_reg_82580(hw, I347AT4_PAGE_SELECT, 0); ret_val = igb_get_phy_id_82575(hw);

Patches currently in stable-queue which might be from asierra@xes-inc.com are

queue-4.9/igb-reset-the-phy-before-reading-the-phy-id.patch