Re: [RESEND PATCH net-next v3 3/4] net: phy: aquantia: wait for the GLOBAL_CFG to start returning real values

Jon Hunter
2024-07-18T14:49:11Z

On 18/07/2024 15:13, Bartosz Golaszewski wrote:
> On Thu, Jul 18, 2024 at 4:08 PM Jon Hunter <jonathanh@nvidia.com> wrote:
>>
>>
>> On 18/07/2024 14:29, Bartosz Golaszewski wrote:
>>> On Thu, Jul 18, 2024 at 3:04 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>>>>
>>>> On Thu, Jul 18, 2024 at 2:23 PM Jon Hunter <jonathanh@nvidia.com> wrote:
>>>>>
>>>>>
>>>>> With the current -next and mainline we are seeing the following issue on
>>>>> our Tegra234 Jetson AGX Orin platform ...
>>>>>
>>>>> Aquantia AQR113C stmmac-0:00: aqr107_fill_interface_modes failed: -110
>>>>> tegra-mgbe 6800000.ethernet eth0: __stmmac_open: Cannot attach to PHY (error: -110)
>>>>>
>>>>>
>>>>> We have tracked it down to this change and looks like our PHY does not
>>>>> support 10M ...
>>>>>
>>>>> $ ethtool eth0
>>>>> Settings for eth0:
>>>>> Supported ports: [ ]
>>>>> Supported link modes: 100baseT/Full
>>>>> 1000baseT/Full
>>>>> 10000baseT/Full
>>>>> 1000baseKX/Full
>>>>> 10000baseKX4/Full
>>>>> 10000baseKR/Full
>>>>> 2500baseT/Full
>>>>> 5000baseT/Full
>>>>>
>>>>> The following fixes this for this platform ...
>>>>>
>>>>> diff --git a/drivers/net/phy/aquantia/aquantia_main.c b/drivers/net/phy/aquantia/aquantia_main.c
>>>>> index d12e35374231..0b2db486d8bd 100644
>>>>> --- a/drivers/net/phy/aquantia/aquantia_main.c
>>>>> +++ b/drivers/net/phy/aquantia/aquantia_main.c
>>>>> @@ -656,7 +656,7 @@ static int aqr107_fill_interface_modes(struct phy_device *phydev)
>>>>> int i, val, ret;
>>>>>
>>>>> ret = phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1,
>>>>> - VEND1_GLOBAL_CFG_10M, val, val != 0,
>>>>> + VEND1_GLOBAL_CFG_100M, val, val != 0,
>>>>> 1000, 100000, false);
>>>>> if (ret)
>>>>> return ret;
>>>>>
>>>>>
>>>>> However, I am not sure if this is guaranteed to work for all?
>>>>
>>>> Ah cr*p. No, I don't think it is. We should take the first supported
>>>> mode for a given PHY I think.
>>>>
>>>
>>> TBH I only observed the issue on AQR115C. I don't have any other model
>>> to test with. Is it fine to fix it by implementing
>>> aqr115_fill_interface_modes() that would first wait for this register
>>> to return non-0 and then call aqr107_fill_interface_modes()?
>>
>> I am doing a bit more testing. We have seen a few issues with this PHY
>> driver and so I am wondering if we also need something similar for the
>> AQR113C variant too.
>>
>> Interestingly, the product brief for these PHYs [0] do show that both
>> the AQR113C and AQR115C both support 10M. So I wonder if it is our
>> ethernet controller that is not supporting 10M? I will check on this too.
>>
>
> Oh you have an 113c? I didn't get this. Yeah, weird, all docs say it
> should support 10M. In fact all AQR PHYs should hence my initial
> change.

Yes we have an AQR113C. I agree it should support this, but for whatever
reason this is not advertised. I do see that 10M is advertised as
supported by the network ...

Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full

My PC that is on the same network supports 10M, but just not this Tegra
device. I am checking to see if this is expected for this device.

Jon

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