On 23-10-2018 11:58, Russell King - ARM Linux wrote:
> On Tue, Oct 23, 2018 at 11:28:09AM +0100, Jose Abreu wrote:
>> On 23-10-2018 11:20, Russell King - ARM Linux wrote:
>>> I have no idea what you're proposing there - your patches weren't copied
>>> to me.
>> They just set / unset MDIO_CTRL1_LPOWER bit in PCS. I find that
>> without this remote end doesn't detect link is down ...
>>
>> If it's okay for Generic 10G driver I can submit only this and
>> manually reset PHY in stmmac driver so that I don't need to
>> implement custom PHY driver ...
>
>
>> BTW, I just found out currently Generic 10G Driver is broken
>> without patch 4/4 of this series [1]
>>
>> [1]
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__patchwork.ozlabs.org_patch_987570_&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=WHDsc6kcWAl4i96Vm5hJ_19IJiuxx_p_Rzo2g-uHDKw&m=zYEDSMZPTCHiPc_3B8buyu0kXnlIEYawnHWAxPrsoSU&s=MlF6I2cBSYkGxgEwNV-hXpXJIvXv_gRYXP-CazjkUSw&e=
> How is it broken - what are the symptoms?
>
> The generic 10G driver is bound not via the normal bus matching and
> phy_bus_match(), but via a manual bind in phy_attach_direct(). This
> calls the probe function, which is phy_probe(), which initialises
> the supported/advertising to the driver's features (which as you note
> are zero.)
Since 719655a14971 ("net: phy: Replace phy driver features u32
with link_mode bitmap"), phy_probe() calls
ethtool_convert_link_mode_to_legacy_u32() with phydrv->features
as argument. Since features are NULL, we will get NULL pointer
dereference.
I guess Generic 10G driver was forgotten in the conversion.
Thanks and Best Regards,
Jose Miguel Abreu
>
> However, phy_attach_direct() goes on to call phy_init_hw(), which
> calls the config_init() method. The config_init() method initialises
> the supported/advertising masks to 10GbaseT. This is (partly) what
> I refer to when I say that the generic 10G support is crippled - it
> only supports this single speed and media.
>
> So the supported/advertising masks should be forced to only 10GbaseT
> at the completion of phy_attach_direct().
>
> The "generic 10G" support doesn't do autonegotiation, configuration
> or link mode forcing. It only assumes 10GbaseT is supported, and
> only checks for the "link up" bits.
>
> It isn't like the non-10G generic PHY support due to history - it
> was added in 2014 by Andy Fleming (see 124059fd53af).
>
> BTW, your patch 1 is wrong as well (introducing phy_update_link()).
> You don't take account that a 10G phy may have alternative ways of
> reading the link (like 88x3310 does, because it has multiple
> instances of AN/PCS/PHYXS at 1k offsets.) All the gen10g_*
> functions are legacy functions for the crippled "generic" 10G
> support.
>
