Displaying 5 results from an estimated 5 matches for "pref_base_upper32".
2018 Aug 28
6
Rewriting Intel PCI bridge prefetch base address bits solves nvidia graphics issues
...2016 with a GTX 9xxM this sequence results in
> hangs on various laptops
> (https://bugzilla.kernel.org/show_bug.cgi?id=156341).
This works fine here. I'm facing a different issue.
>> After a lot of experimentation I found a workaround: during resume,
>> set the value of PCI_PREF_BASE_UPPER32 to 0 on the parent PCI bridge.
>> Easily done in drivers/pci/quirks.c. Now all nvidia stuff works fine.
>
> I am curious, how did you discover this? While this could work, perhaps
> there are alternative workarounds/fixes?
Based on the observation that the following procedure works...
2018 Aug 29
0
Rewriting Intel PCI bridge prefetch base address bits solves nvidia graphics issues
...uence results in
>> hangs on various laptops
>> (https://bugzilla.kernel.org/show_bug.cgi?id=156341).
>
> This works fine here. I'm facing a different issue.
>
>>> After a lot of experimentation I found a workaround: during resume,
>>> set the value of PCI_PREF_BASE_UPPER32 to 0 on the parent PCI bridge.
>>> Easily done in drivers/pci/quirks.c. Now all nvidia stuff works fine.
>>
>> I am curious, how did you discover this? While this could work, perhaps
>> there are alternative workarounds/fixes?
>
> Based on the observation that the f...
2018 Aug 28
0
Rewriting Intel PCI bridge prefetch base address bits solves nvidia graphics issues
...lessm kernel on Github seems to have quite some
patches, one of them explicitly disable runtime PM:
https://github.com/endlessm/linux/commit/8b128b50cd6725eee2ae9025a1510a221d9b42f2
> >> After a lot of experimentation I found a workaround: during resume,
> >> set the value of PCI_PREF_BASE_UPPER32 to 0 on the parent PCI bridge.
> >> Easily done in drivers/pci/quirks.c. Now all nvidia stuff works fine.
> >
> > I am curious, how did you discover this? While this could work, perhaps
> > there are alternative workarounds/fixes?
>
> Based on the observation that...
2018 Aug 24
2
Rewriting Intel PCI bridge prefetch base address bits solves nvidia graphics issues
...output is all black
or
1. Boot
2. Load proprietary nvidia driver
3. Start X
4. Suspend/resume
5. Observe screen all black, Xorg using 100% CPU
So, suspend/resume basically kills the nvidia card in some way.
After a lot of experimentation I found a workaround: during resume,
set the value of PCI_PREF_BASE_UPPER32 to 0 on the parent PCI bridge.
Easily done in drivers/pci/quirks.c. Now all nvidia stuff works fine.
As an example of an affected product, take the Asus X542UQ (Intel
KabyLake i7-7500U with Nvidia GeForce 940MX). The PCI bridge is:
00:1c.0 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI...
2018 Sep 07
9
[PATCH] PCI: Reprogram bridge prefetch registers on resume
..., and their response indicated that it's a
problem with the parent PCI bridge (on the Intel SoC), not the GPU.
Runtime suspend/resume works fine, only S3 suspend is affected.
We found a workaround: on resume, rewrite the Intel PCI bridge
'Prefetchable Base Upper 32 Bits' register (PCI_PREF_BASE_UPPER32). In
the cases that I checked, this register has value 0 and we just have to
rewrite that value.
It's very strange that rewriting the exact same register value
makes a difference, but it definitely makes the issue go away.
It's not just acting as some kind of memory barrier, because rewrit...