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

From: Kishon Vijay Abraham I
Date: Tue Dec 24 2013 - 12:46:45 EST


Hi,

On Thursday 05 December 2013 01:44 PM, Vivek Gautam wrote:
Hi Kishon,


On Wed, Dec 4, 2013 at 7:58 PM, Kishon Vijay Abraham I <kishon@xxxxxx> 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@xxxxxx> 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@xxxxxx> 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@xxxxxxxxxxx> 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.

Irrespective of whether we are able to test the functionality separately or not, we should model it as multiple PHYs since you have separate bit settings for UTMI+ and PIPE3.

(I'll review your next patch version shortly).

Cheers
Kishon

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




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