svn commit: r339382 - projects/power8_bringup_hacks/sys/dev/bge

[Leandro]

The issue seems to be related to wrong configuration of DMA regions in
opal_pci.c, which affects all PowerNV platforms.
This is where I'm going to look next, that, if solved, we should be
able to remove this hack.
This is just to make the network interface stable, until the real
issue is resolved.
On Tue, Oct 16, 2018 at 1:55 PM John Baldwin <jhb at freebsd.org> wrote:
>
> On 10/16/18 9:36 AM, Leandro Lupori wrote:
> > Author: luporl
> > Date: Tue Oct 16 16:36:02 2018
> > New Revision: 339382
> > URL: https://svnweb.freebsd.org/changeset/base/339382
> >
> > Log:
> >   bge(4): limit DMA address to 2GB
> >
> >   This is a temporary hack, to avoid POWER8 Broadcom NICs from becoming
> >   unusable after transferring a reasonable amount of data.
> >   The issue is the same as that of AHCI, where DMA addresses above 2GB
> >   do not work and causes PCI errors.
>
> Is the issue bge specific or specific to the PCI chipset in these boxes?
> If the latter, the better approach would be to set the limit in a tag the
> chipset provides that all child devices would then inherit.
>
> --
> John Baldwin
>
>