Re: [PATCH net-next v2] macb: Common code to enable ptp support for MACB/GEM

[Nicolas Ferre]

Le 27/01/2017 Ã 11:26, Rafal Ozieblo a Ãcrit :
>> -----Original Message-----
>> From: Harini Katakam [mailto:harinikatakamlinux@xxxxxxxxx] 
>> Sent: 27 stycznia 2017 06:43
>> Subject: Re: [PATCH net-next v2] macb: Common code to enable ptp support for MACB/GEM
>>
>> Hi Rafal,
>>
>> On Thu, Jan 26, 2017 at 8:45 PM, Rafal Ozieblo <rafalo@xxxxxxxxxxx> wrote:
>>>> -----Original Message-----
>>>> From: Andrei Pistirica [mailto:andrei.pistirica@xxxxxxxxxxxxx]
>>>> Sent: 19 stycznia 2017 16:56
>>>> Subject: [PATCH net-next v2] macb: Common code to enable ptp support for MACB/GEM
>>>>
>>>>
>>>> +static inline bool gem_has_ptp(struct macb *bp)
>>>> +{
>>>> +     return !!(bp->caps & MACB_CAPS_GEM_HAS_PTP);
>>>> +}
>>> Why don't you use hardware capabilities here? Would it be better to read it from hardware instead adding it to many configuration?
>>
>> If you are referring to TSU bit in DCFG5, then we will be relying on
>> Cadence IP's information irrespective of the SoC capability
>> and whether the PTP support was adequate.
>> I think the capability approach gives better control and
>> it is not really much to add.
>>
>> Regards,
>> Harini
>>
> Yes, I'm referring to TSU bit.
> What if SoC contains multiple Cadence GEMs, some with PTP support and others without?

Simply define different DT compatibility strings and we're good.

> Relevant will be checking both, hardware capabilities and SoC capabilities from "caps" field.
> 


-- 
Nicolas Ferre