Re: [PATCH v6 3/6] net: phy: at803x: add QCA8084 ethernet phy support

Jie Luo
2023-11-28T09:51:26Z

On 11/28/2023 5:00 PM, Russell King (Oracle) wrote:
> On Tue, Nov 28, 2023 at 03:16:45PM +0800, Jie Luo wrote:
>>>> The interface mode is passed in the .config_init, which is configured
>>>> by the PCS driver, the hardware register is located in the PCS, this
>>>> driver will be pushed later.
>>>
>>> Is this the same as how the syqca807x works? Can the PCS driver be
>>> shared by these two drivers?
>>
>> I am not sure syqca807x, would you point me the code path of this driver?
>>
>>>
>>> What i don't like at the moment is that we have two driver
>>> developments going on at once for hardware which seems very similar,
>>> but no apparent cooperation?
>>>
>>> Andrew
>>
>> The PCS of qca8084 is the PHY PCS, which should be new PCS driver,
>> in the previous chips, we don't have this kind of PHY PCS.
>
> No. PCS drivers are for MAC-side PCS drivers, not PHY-side PCS drivers.
>
> +-------------
> | PHY
> MAC---PCS --- link --- PCS --- ...
> ^ | ^
> | +--|----------
> For this PCS |
> Not for this PCS
>

The PCS drivers in drivers/net/pcs/ should be in PHY side, such as
pcs-lynx.c and pcs-xpcs.c, they are configuring the MDIO device
registers.