Re: [PATCH net] net: bcmgenet: fix bcmgenet_get_eee() clobbered by phy_ethtool_get_eee()

On Thu, Mar 05, 2026 at 09:50:29AM +0100, Nicolai Buchwitz wrote:

On 4.3.2026 22:57, Andrew Lunn wrote:

quoted

On Tue, Mar 03, 2026 at 04:39:18PM +0100, Nicolai Buchwitz wrote:

quoted

bcmgenet_get_eee() sets the MAC-managed tx_lpi_enabled and
tx_lpi_timer
fields, then calls phy_ethtool_get_eee() which internally calls
eeecfg_to_eee() — overwriting eee_enabled, tx_lpi_enabled and
tx_lpi_timer with the PHY's eee_cfg values.  For non-phylink MACs like
GENET, these PHY-level fields are never initialized (they are only set
by phylink via phy_support_eee()), so the ethtool report always shows
eee_enabled=false and tx_lpi_enabled=false regardless of the actual
MAC
state.

I think the MAC driver is missing a call to phy_support_eee() to let
phylib know the MAC supports EEE. Have you tried that.

Thanks for the suggestion. I've incorporated phy_support_eee() and tested it
with a Raspberry CM4.

After applying the patch, the PHY correctly advertises EEE, negotiates it
with
the link partner, and ethtool reports:

  EEE status: enabled - active

Great, so we are going in the right direction.

The whole point of the reworking of EEE and putting as much as
possible into the phylib was that many MAC drivers were broken, and
the behaviour between MAC drivers was inconsistent. I had a big
patchset which converted every MAC driver, removing nearly all the EEE
code. Unfortunately, not all the patches got merged, and we ended up
with some MAC drivers in a half way state.

Please look at removing all the state tracking in the MAC driver. When
the adjust_link callback is made, look at the state in phydev, and
configure the hardware based on that. As an example, look at

https://elixir.bootlin.com/linux/v6.19.3/source/drivers/net/ethernet/freescale/fec_main.c#L2129

	Andrew