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

[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?

If so, I'll drop the patch until we figure this out.  But if the GPU
power issue also occurs in v4.19-rc5, I think we can assume it's a
different problem and we can go ahead and merge [1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/commit/?h=for-linus&id=083874549fdfefa629dfa752785e20427dde1511