[U-Boot] xHCI on x86

[Stefan Roese <sr@denx.de>]

Hi Simon,

On 15.07.2016 05:19, Simon Glass wrote:
> On 13 July 2016 at 00:20, Stefan Roese <sr@denx.de> wrote:
>> Hi!
>>
>> I'm currently trying to get xHCI working on some BayTrail based
>> x86 boards. For this I've added DM support to xhci-pci and made a
>> small change to cache.h to enable compilation of the xhci driver on
>> x86 (please find those 2 patches attached - I'll send then to the
>> list once this is resolved). But I noticed that the xhci driver
>> hangs in xhci_queue_command() in this line:
>>
>>          xhci_writel(&ctrl->dba->doorbell[0], DB_VALUE_HOST);
>>
>> when first writing to the doorbell register. Reading from this doorbell
>> register still works just fine.
>>
>> IIRC, Simon has mentioned that xHCI still has some "issues" on x86.
>> Simon, is this what you have seen as well? Does anyone have some ideas
>> how to solve this?
>
> I'm really not sure what is wrong, sorry. The discussion about
> enabling the pin settings correctly may be relevant since I believe
> two GPIOs need to be set up for both ports to work, and that patch was
> never cleaned up and applied, so far as I know...

I see.

I my case, it's not related to the GPIO issue - as the ports are not
enabled via GPIO on the Congatec board where I'm currently testing on.
I've updated the xHCI PCI support a bit (no hangup any more, but still
not working correctly) and will post the current version as WIP today,
as I need to switch to some other tasks for a while. Perhaps someone
else is interested in xHCI on x86 enough to take a look at it in the
meantime...

Thanks,
Stefan