Re: [PATCH net-next] net: phy: improve handling link_change_notify callback

[Russell King - ARM Linux admin <linux@armlinux.org.uk>]

On Tue, Mar 12, 2019 at 06:50:59PM +0100, Daniel Mack wrote:
> On 12/3/2019 1:27 PM, Heiko Stuebner wrote:
> > Hi Andrew, Heiner,
> > 
> > Am Montag, 4. März 2019, 21:06:30 CET schrieb Andrew Lunn:
> >> On Mon, Mar 04, 2019 at 11:30:25AM -0800, David Miller wrote:
> >>> From: Heiner Kallweit <hkallweit1@gmail.com>
> >>> Date: Sun, 3 Mar 2019 19:58:57 +0100
> >>>
> >>>> Currently the Phy driver's link_change_notify callback is called
> >>>> whenever the state machine is run (every second if polling), no matter
> >>>> whether the state changed or not. This isn't needed and may confuse
> >>>> users considering the name of the callback. Therefore let's change
> >>>> the behavior and call this callback only in case of an actual
> >>>> state change.
> >>>>
> >>>> This requires changes to the at803x and rockchip drivers.
> >>>> at803x can be simplified so that it reacts on a state change to
> >>>> PHY_NOLINK only.
> >>>> The rockchip driver can also be much simplified. We simply re-init
> >>>> the AFE/DSP registers whenever we change to PHY_RUNNING and speed
> >>>> is 100Mbps. This causes very small overhead because we do this even
> >>>> if the speed was 100Mbps already. But this is neglectable and
> >>>> I think justified by the much simpler code.
> >>>>
> >>>> Changes are compile-tested only.
> >>>>
> >>>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> >>>
> >>> Someone please review this.
> >>
> >> Hi David
> >>
> >> We should probably wait for a Tested-by: from Daniel Mack
> >> <zonque@gmail.com> and David Wu <david.wu@rock-chips.com>, or
> >> equivalent.
> > 
> > We should probably add them to the list of recipients if we want
> > tests from them, which I've done now.
> > 
> > @David: patch in question that changes the Rockchip eth-phy is
> > https://patchwork.kernel.org/patch/10837217/
> > 
> > Sadly I don't have matching hardware to test this myself.
> 
> Thanks for considering me, but I don't have access to that hardware
> either right now.
> 
> The changes look straight forward to me however, so just go ahead an
> apply this. Once I get back to that setup, I'll report in case of a
> regression.

SolidRun Hummingboards and Cubox-i use AR8035 with the FEC driver, so
would be ideal to test - unfortunately I'm up to my eyeballs trying to
diagnose Armada 8040 comphy issues so can't test at the moment.

-- 
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