e1000e: Workaround for sporadic MDI error on Meteor Lake systems

On some Meteor Lake systems accessing the PHY via the MDIO interface may
result in an MDI error. This issue happens sporadically and in most cases
a second access to the PHY via the MDIO interface results in success.

As a workaround, introduce a retry counter which is set to 3 on Meteor
Lake systems. The driver will only return an error if 3 consecutive PHY
access attempts fail. The retry mechanism is disabled in specific flows,
where MDI errors are expected.

Fixes: cc23f4f0b6b9 ("e1000e: Add support for Meteor Lake")
Suggested-by: Nikolay Mushayev <nikolay.mushayev@intel.com>
Co-developed-by: Nir Efrati <nir.efrati@intel.com>
Signed-off-by: Nir Efrati <nir.efrati@intel.com>
Signed-off-by: Vitaly Lifshits <vitaly.lifshits@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

0 files changed, 0 insertions, 0 deletions