[Skiboot] [PATCH v2 00/16] opencapi: enable card reset and link retraining

[Oliver O'Halloran]

On Thu, Oct 10, 2019 at 6:38 AM Frederic Barrat <fbarrat at linux.ibm.com> wrote:
>
> This series adds support in skiboot to allow linux to reset an
> opencapi adapter. The main intent is to refresh linux' view of the
> devices when flashing a new FPGA image on the adapter.
>
> I had sent a previous iteration as an RFC, which was built on top of a
> series from Oliver modifying the slot power controls for hotplug. This
> new version is now independent. It hopefully doesn't conflict too much
> with what Oliver was trying to do, though I'm expecting some
> discussions.
>
> The approach taken is to use the PCI hotplug framework. We define a
> slot for the (virtual) opencapi PHB. It allows linux to control the
> slot state to unplug (set the opencapi adapter in reset) and replug
> (release reset and retrain the link). On replug, the PCI devices go
> through PCI enumeration, so BARs for the new image will be properly
> reassigned.
>
> The first few patches modify the PCI hotplug framework to retrain a
> PHB slot when powering on. The 2nd part of the series are fixes to
> allow to retrain an already trained opencapi link. The last part is to
> allow an opencapi slot to be used by the PCI hotplug framework.
>
> We have a dependency on the version of the DLx and TLx used on the
> FPGA to make sure they are reset properly. The hw enablement team has
> provided fixes for it for a while now, so we should be good.

Merged as of f6f247a8c468