[U-Boot] Porting ehci-exynos.c to handle exynos4412 (odroid-u2)

[Suriyan Ramasami]

Yes, the u-boot is based off of 2010.12:
The source with the odroid-u2 (Exynos4412) mods are in
https://github.com/hardkernel/u-boot

You are right, the problem is in enabling USB. I do not seem ot find
documentation as to the IO addresses and what values to poke/peek in them
to initialize and power on the USB PHY.

There is however a linux source tree which has support for this device,
which works the USB quite well. I am trying to steal and grab the
initialization steps from the linux kernel and pull it into u-boot.

The files that I seem to need to modify are mainly in
drivers/host/usb/ehci-exynos.c with some usb phy power code in
system.c/power.c in arch/arm/cpu/armv7/exynos/ in u-boot. The linux src
tree that I am trying to decipher is in arch/arm/mach-exynos/setup-usb-phy.c

Thanks
- Suriyan


On Mon, Jul 8, 2013 at 12:47 PM, Lukasz Majewski <l.majewski at majess.pl>wrote:

> On Mon, 8 Jul 2013 11:03:05 -0700
> Suriyan Ramasami <suriyan.r at gmail.com> wrote:
>
> > Hello Lukasz,
> >    Thanks for your response. I guess I was not very clear with my
> > question.
> >
> >    u-boot code already exists for the odroid-u2 (that is what it
> > uses).
>
> So I assume that the u-boot code was the part of the BSP?
> The problem then seems to be with enabling and building the usb code?
>
> Another question is, how close your odroid's u-boot is to the mainline?
> Which version of u-boot do you have?
>
> > Unfortunately, it does not have USB support. I am looking at
> > just adding the EHCI and USB (uses a 3503A) part of the code.
> >
> >    I checked the TRATS2 patch and it too does not have any code that
> > touches the USB part of things.
>
> This is true. We aren't using EHCI (USB Host). Instead we are
> supporting USB Device + Composite layer + Gadgets (like DFU + UMS).
> Support for those devices is "almost" in mainline :-).
>
> Regards,
> Lukasz Majewski
>
> >
> > Thanks
> > - Suriyan
> >
> >
> > On Sun, Jul 7, 2013 at 11:56 PM, Lukasz Majewski
> > <l.majewski at samsung.com>wrote:
> >
> > > On Sun, 07 Jul 2013 02:15:17 -0700, Suriyan Ramasami wrote:
> > >
> > > Hi Suriyan,
> > >
> > > > Hi wonderful folks!
> > > >
> > > >     I own an odroid-u2 and the u-boot that comes with it does not
> > > > have usb support. Its configuration is smdk4412 and I do not find
> > > > that in the u-boot sources. I see it in the arndale and harkernel
> > > > branches.
> > > >
> > > >    I do see that usb support was added to the arndale platform -
> > > > which is exynos5 based. Is it easy to port it for exynos4412?
> > >
> > > Patches for Exynos4412 based board (TRATS2) were already sent on the
> > > mailing list:
> > >
> > >
> > >
> http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/161578/match=introduce+samsung's+new+board+trats2
> > >
> > > Please refer to them. It shall be relatively easy to add odroid-u2
> > > support based on TRATS2.
> > >
> > > >
> > > >    I did try it porting on my own accord and am listing it
> > > > below...
> > > >
> > > >    I seem to be hitting issues in drivers/usb/host/ehci-exynos.c
> > > > -> function setup_usb_phy(struct exynos_usb_phy *usb).
> > > > Would passing the correct address of usb for the exynos4412 do the
> > > > trick? If so what should it be?
> > > >   In this same file ehci_hcd_init() uses gpio->x3 and gpio->d1. In
> > > > exynos4 looks like x3 is from gpio_part2. Also, do the d1 and x3
> > > > translate to the same gpiod1 and gpiox3 in the exynos4412?
> > > >
> > > > Furthermore, ehci-exynos.c uses functions from
> > > > arch/arm/cpu/armv7/exynos/system.c which for the most part  are
> > > > exynos5 oriented and do nothing for exynos4.
> > > >
> > > > Can someone guide me as to what I could do, or some pointers to
> > > > helpful docs? I do have the Exynos 4412 user manual.
> > > >
> > > > Thanks
> > > > - Suriyan
> > >
> > >
> > > --
> > > Best regards,
> > >
> > > Lukasz Majewski
> > >
> > > Samsung R&D Institute Poland (SRPOL) | Linux Platform Group
> > >
>
>