[PATCH RFC 1/4] phy: Add new Exynos5 USB 3.0 PHY driver

Vivek Gautam gautamvivek1987 at gmail.com
Thu Dec 5 03:14:36 EST 2013


Hi Kishon,


On Wed, Dec 4, 2013 at 7:58 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
> Hi Vivek,
>
> On Wednesday 20 November 2013 09:14 PM, Kishon Vijay Abraham I wrote:
>> Hi,
>>
>> On Wednesday 20 November 2013 03:02 PM, Vivek Gautam wrote:
>>> On Wed, Nov 20, 2013 at 2:34 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
>>>> On Wednesday 20 November 2013 02:27 PM, Vivek Gautam wrote:
>>>>> Hi Kishon,
>>>>>
>>>>>
>>>>> On Mon, Nov 11, 2013 at 4:41 PM, Kishon Vijay Abraham I <kishon at ti.com> wrote:
>>>>>> Hi,
>>>>> sorry for the delayed response.
>>>>>
>>>>>>
>>>>>> On Wednesday 06 November 2013 05:37 AM, Jingoo Han wrote:
>>>>>>> On Wednesday, November 06, 2013 2:58 AM, Vivek Gautam wrote:
>>>>>>>> On Tue, Nov 5, 2013 at 5:33 PM, Jingoo Han <jg1.han at samsung.com> wrote:
>>>>>>>
>>>>>>> [.....]
>>>>>>>
>>>>>>>>> USB3.0 PHY consists of two blocks such as 3.0 block and 2.0 block.
>>>>>>>>> This USB3.0 PHY can support UTMI+ and PIPE3 interface for 3.0 block
>>>>>>>>> and 2.0 block, respectively.
>>>>>>>>>
>>>>>>>>> Conclusion:
>>>>>>>>>
>>>>>>>>>    1) USB2.0 PHY: USB2.0 HOST, USB2.0 Device
>>>>>>>>>                        Base address: 0x1213 0000
>>>>>>>>>
>>>>>>>>>    2) USB3.0 PHY: USB3.0 DRD (3.0 HOST & 3.0 Device)
>>>>>>>>>                        Base address: 0x1210 0000
>>>>>>>>>                        2.0 block(UTMI+) & 3.0 block(PIPE3)
>>>>>>>>
>>>>>>>> And this is of course the PHY used by DWC3 controller, which works at
>>>>>>>> both High speed as well as Super Speed.
>>>>>>>> Right ?
>>>>>>>
>>>>>>> Right.
>>>>>>>
>>>>>>> While 3.0 block(PIPE3) can be used for Super Speed, 2.0 block(UTMI+)
>>>>>>> can be used for High speed.
>>>>>>
>>>>>> It should then come under *single IP muliple PHY* category similar to what
>>>>>> Sylwester has done.
>>>>>
>>>>> Do you mean that i should be including PHY IDs for UTMI+ phy and PIPE3
>>>>> phy present in this PHY block ?
>>>>> AFAICS the two phys (UTMI+ and PIPE3) do not really have separate
>>>>> registers to program, and that's the reason
>>>>> we program the entire PHY in a shot.
>>>>
>>>> you mean you program the same set of bits for UTMI+ and PIPE3?
>>>
>>> No, looking closely into PHY datasheet as well as Exynos5250 manual, i
>>> can see that UTMI+ and PIPE3
>>> phys have separate bit settings. So i think we should be able to
>>> segregate the two PHYs (UTMI+ and PIPE3).
>>> Pardon me for my earlier observations.
>>
>> no problem..
>>> Let me clarify more with our h/w team also on this and then i will
>>> confirm with this.
>
> Did you get more information on this?

Yes, i have been in contact with our hardware team.
The functionality of setting up UTMI+ and PIPE3 phys separately, and
thereby using only one functionality of the two
at some point of time (either high speed or super speed) hasn't been
tested so far.
So i will be looking into this and try to find out proper init
sequences for the two available PHYs
separately and as soon as i get a working solution for this, i will update.

>
> Thanks
> Kishon



-- 
Best Regards
Vivek Gautam
Samsung R&D Institute, Bangalore
India



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