Re: [PATCH v3] net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)

[Oleksij Rempel]

On Thu, Aug 31, 2023 at 09:25:27AM +0200, Lukasz Majewski wrote:
> The KSZ9477 errata points out (in 'Module 4') the link up/down problems
> when EEE (Energy Efficient Ethernet) is enabled in the device to which
> the KSZ9477 tries to auto negotiate.
> 
> The suggested workaround is to clear advertisement of EEE for PHYs in
> this chip driver.
> 
> To avoid regressions with other switch ICs the new MICREL_NO_EEE flag
> has been introduced.
> 
> Moreover, the in-register disablement of MMD_DEVICE_ID_EEE_ADV.MMD_EEE_ADV
> MMD register is removed, as this code is both; now executed too late
> (after previous rework of the PHY and DSA for KSZ switches) and not
> required as setting all members of eee_broken_modes bit field prevents
> the KSZ9477 from advertising EEE.
> 
> Fixes: 69d3b36ca045 ("net: dsa: microchip: enable EEE support") (for KSZ9477).
> 
> Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>
 
Tested-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>

Confirmed disabled EEE with oscilloscope.

Reviewed-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>

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