[coreboot] Using eMMC on Baytrail with FSP

David Popeck david at justaride.org
Fri Jan 15 15:56:17 CET 2016


Hi Ben,

I've had some success now.

Once I knew that you had it working with eMMC without any real fiddling, I
went on the assumption that an older version of coreboot would be worth
trying.

I had been using the latest version from github but have now gone back to
the version of code that Intel supplied with FSP Gold 4, which works!

So either something didn't get integrated into the official coreboot source
or its broken between then and now.
When I get some time I will try and track down exactly where the difference
is.
For now I'm just glad I'm not spending the weekend in the office!

Thanks

David



On Thu, Jan 14, 2016 at 5:36 PM, Ben Gardner <gardner.ben at gmail.com> wrote:

> Hi David,
>
> I've been using eMMC with the baytrail FSP on the E3800 CPU without issue.
> I don't recall doing anything special to get it to work under Linux.
>
> Comparing my devicetree.cb with bayleybay_fsp shows these differences
> related to eMMC.
> I don't know if any of those are important.
>
> register "PcdEMMC45DDR50Enabled"   = "EMMC45_DDR50_DISABLE"
> register "PcdEMMC45HS200Enabled"     = "EMMC45_HS200_DISABLE"
> register "PcdEMMC45RetuneTimerValue" = "EMMC45_RETURN_TIMER_DEFAULT"
>
> I also have devices 0x11 and 0x12 turned off.
>
> By "relevant" pins, I assume you mean GPIO_S0_SC[016] thru GPIO_S0_SC[026].
>
> Ben
>
> On Wed, Jan 13, 2016 at 9:16 AM, David Popeck <david at justaride.org> wrote:
> > Hi all,
> >
> > I've been trying to get Coreboot going on a custom Baytrail based board
> that
> > I have.
> >
> > Pretty much everything is working with one major exception - eMMC.
> >
> > I've enabled eMMC in BCT.
> > In devicetree.cb I've switched off device 10 (eMMC 4.1 controller) and
> > switched on device 17 (eMMC 4.5 controller).
> > And finally I've switched the relevent pins to GPIO_FUNC3 in gpio.c.
> >
> > Linux sees device 17.0 in lspci and loads the module but doesn't show any
> > mmcblk devices.
> >
> > I was supplied the board with an Insyde systems EFI firmware which I
> really
> > don't want to use.
> > This does recognise the eMMC, boots the same kernel I used with coreboot
> and
> > now I can access the eMMC.
> > So I know there is nothing electrically wrong here.
> >
> >
> > Should this configuration work with coreboot?
> > If I look in the non-fsp baytrail directory I can see emmc.c which
> appears
> > to contain explicit code to initialise the controller.
> > There is no equivelent code in the fsp_baytrail directory that I can see.
> > Is FSP supposed to initialise the controller or is there something
> missing
> > here?
> >
> >
> > Thanks for any help
> >
> > David
> >
> >
> >
> > --
> > coreboot mailing list: coreboot at coreboot.org
> > http://www.coreboot.org/mailman/listinfo/coreboot
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.coreboot.org/pipermail/coreboot/attachments/20160115/a5646423/attachment.html>


More information about the coreboot mailing list