[Intel-wired-lan] [PATCH v4] e1000e: Increase polling timeout on MDIC ready bit
Kai-Heng Feng
kai.heng.feng at canonical.com
Tue Sep 29 15:08:23 UTC 2020
> On Sep 29, 2020, at 21:46, Neftin, Sasha <sasha.neftin at intel.com> wrote:
>
> Hello Kai-Heng,
> On 9/29/2020 16:31, Kai-Heng Feng wrote:
>> Hi Sasha,
>>> On Sep 29, 2020, at 21:08, Neftin, Sasha <sasha.neftin at intel.com> wrote:
>>>
>>> On 9/28/2020 11:36, Kai-Heng Feng wrote:
>>>> We are seeing the following error after S3 resume:
>>>> [ 704.746874] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>>>> [ 704.844232] e1000e 0000:00:1f.6 eno1: MDI Write did not complete
>>>> [ 704.902817] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>>>> [ 704.903075] e1000e 0000:00:1f.6 eno1: reading PHY page 769 (or 0x6020 shifted) reg 0x17
>>>> [ 704.903281] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>>>> [ 704.903486] e1000e 0000:00:1f.6 eno1: writing PHY page 769 (or 0x6020 shifted) reg 0x17
>>>> [ 704.943155] e1000e 0000:00:1f.6 eno1: MDI Error
>>>> ...
>>>> [ 705.108161] e1000e 0000:00:1f.6 eno1: Hardware Error
>>>> As Andrew Lunn pointed out, MDIO has nothing to do with phy, and indeed
>>>> increase polling iteration can resolve the issue.
>>>> This patch only papers over the symptom, as we don't really know the
>>>> root cause of the issue. The most possible culprit is Intel ME, which
>>>> may do its own things that conflict with software.
>>>> Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
>>>> ---
>>>> v4:
>>>> - States that this patch just papers over the symptom.
>>>> v3:
>>>> - Moving delay to end of loop doesn't save anytime, move it back.
>>>> - Point out this is quitely likely caused by Intel ME.
>>>> v2:
>>>> - Increase polling iteration instead of powering down the phy.
>>>> drivers/net/ethernet/intel/e1000e/phy.c | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>> diff --git a/drivers/net/ethernet/intel/e1000e/phy.c b/drivers/net/ethernet/intel/e1000e/phy.c
>>>> index e11c877595fb..e6d4acd90937 100644
>>>> --- a/drivers/net/ethernet/intel/e1000e/phy.c
>>>> +++ b/drivers/net/ethernet/intel/e1000e/phy.c
>>>> @@ -203,7 +203,7 @@ s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data)
>>>> * Increasing the time out as testing showed failures with
>>>> * the lower time out
>>>> */
>>>> - for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) {
>>>> + for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 10); i++) {
>>> As we discussed (many threads) - AMT/ME systems not supported on Linux as properly. I do not think increasing polling iteration will solve the problem. Rather mask it.
>> I am aware of the status quo of no proper support on Intel ME.
>>> I prefer you check option to disable ME vi BIOS on your system.
>> We can't ask user to change the BIOS to accommodate Linux. So before a proper solution comes out, masking the problem is good enough for me.
>> Until then, I'll carry it as a downstream distro patch.
> What will you do with system that even after increasing polling time will run into HW error?
Hope we finally have proper ME support under Linux?
Kai-Heng
>> Kai-Heng
>>>> udelay(50);
>>>> mdic = er32(MDIC);
>>>> if (mdic & E1000_MDIC_READY)
>>> Thanks,
>>> Sasha
> Thanks,
> Sasha
More information about the Intel-wired-lan
mailing list