[PATCH v2 3/5] ata: Add APM X-Gene SATA driver

Loc Ho lho at apm.com
Wed Nov 13 01:02:42 EST 2013


Hi,

I need an method to tell the PHY layer to go to an specific speed -
Gen2 or Gen1. Consider it is an limitation of our PHY. This is done
after link up.

-Loc

On Tue, Nov 12, 2013 at 9:55 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
> Hi,
>
> On Wednesday 13 November 2013 11:03 AM, Loc Ho wrote:
>> Hi,
>>
>> If I need to call a function into the PHY driver to say force an
>> specific speed, how would one do this? I notice the USB have a bunch
>
> There are a bunch of *ops* currently available in the PHY framework which you
> can use like phy_init, phy_exit, phy_power_on, phy_power_off. That should be
> good enough IMO. If you need any other ops we can have a discussion here.
>
> Thanks
> Kishon
>> of functions. Would I need to introduce an structure for SATA as well
>> that have a number of required functions that upper layer can call?
>>
>> -Loc
>>
>> On Tue, Nov 12, 2013 at 9:20 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
>>> Hi,
>>>
>>> On Wednesday 13 November 2013 04:09 AM, Loc Ho wrote:
>>>> Hi Arnd,
>>>>
>>>> I looked at the PHY generic framework and come across this statement
>>>> below. Our SATA PHY is embedded into the SoC. Should I ignore this
>>>
>>> Is your PHY embedded into the SoC or embedded into the SATA controller? If it's
>>> within the SoC but not embedded into the SATA controller, you can use PHY
>>> framework as the PHY is in a different IP and has a separate address space for
>>> itself.
>>> If it's within the SATA controller, then you might very well implement the PHY
>>> logic in your SATA controller driver itself.
>>>> statement below and implement the PHY driver using this framework?
>>>>
>>>> +This framework will be of use only to devices that use external PHY (PHY
>>>> +functionality is not embedded within the controller).
>>>
>>> It means for PHYs embedded within the SATA controller and not within the SoC ;-)
>>>
>>> Thanks
>>> Kishon
>>>>
>>>> -Loc
>>>>
>>>>
>>>> On Tue, Nov 12, 2013 at 5:11 AM, Arnd Bergmann <arnd at arndb.de> wrote:
>>>>> On Tuesday 12 November 2013, Loc Ho wrote:
>>>>>> Hi Arnd/Olof,
>>>>>>
>>>>>> I looked over the phy code for USB and NET. There isn't such PHY
>>>>>> infrastructure for SATA from what I can tell. It seems like I will
>>>>>> need to put this all together. I am thinking about porting the USB
>>>>>> version over (with changes for SATA) and put it under
>>>>>> "./drivers/ata/phy". Any suggestion?
>>>>>
>>>>> Please have a look at the patches under the subject "Generic PHY Framework"
>>>>> posted by Kishon Vijay Abraham. I thought they would have made it in
>>>>> by now, but I have not followed the recent kernels closely since I am
>>>>> on parental leave at the moment.
>>>>>
>>>>> IIRC they should unify USB, SATA and other PHY codes, but not network.
>>>>>
>>>>>         Arnd
>>>
>



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