Re: [PATCH v3] PCI: Reprogram bridge prefetch registers on resume

[Bjorn Helgaas]

On Tue, Oct 2, 2018 at 4:27 PM Thomas Martitz <kugel@xxxxxxxxxxx> wrote:
>
> Am 02.10.18 um 22:03 schrieb Bjorn Helgaas:
> > Hi Thomas,
> >
> > On Mon, Oct 01, 2018 at 04:25:06PM +0200, Thomas Martitz wrote:
> >> Am 01.10.18 um 06:57 schrieb Daniel Drake:
> >>> On Sun, Sep 30, 2018 at 5:07 AM Thomas Martitz <kugel@xxxxxxxxxxx> wrote:
> >>>> The latest iteration does not work on my HP system. The GPU fails to
> >>>> power up just like the unpatched kernel.
> >>>
> >>> That's weird, I would not expect a behaviour change in the latest
> >>> patch. pci_restore_config_dword() has some debug messages, could you
> >>> please make them visible and show logs again?
> >>> Also remind us of the PCI device address of the parent bridge (lspci -vt)
> >>
> >> I'll follow up with more the requested information on bugzilla
> >> (Link: https://bugzilla.kernel.org/show_bug.cgi?id=201069).
> >>
> >> On a quick re-check, it seems to depend on if I used the eGPU before
> >> the initial suspend. If I run glxgears (with DRI_PRIME=1) before suspend it
> >> seems fine.
> >
> > Does the patch ([1]) make things *worse* compared to v4.19-rc5?
> >
>
> No, certainly not. It does look like a different issue since resuming now
> works at least if I used the eGPU in some way before suspend
> (DRI_PRIME=1 glxgears seems to be enough, I assume glxinfo would work as
> well).
>
> Without the patch resuming the eGPU does not work whatsoever.
>
> Please ship the patch. I'll hopefully sort this other issue out.

Great, thanks!  That's what I thought, but just wanted to double check.