Messages in this thread | | | Date | Thu, 14 Dec 2023 11:28:48 -0600 | From | Bjorn Helgaas <> | Subject | Re: [PATCH v2 1/6] PCI/ASPM: Add locked helper for enabling link state |
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On Wed, Dec 13, 2023 at 03:39:24PM -0800, David E. Box wrote: > On Wed, 2023-12-13 at 14:45 -0600, Bjorn Helgaas wrote: > ...
> > I'd be shocked if Windows treated the BIOS config as a "do not exceed > > this" situation, so my secret hope is that some of these "broken" > > devices are really caused by defects in the Linux ASPM support or the > > driver, and that we can fix them if we find out about them. > > > > But I have no details about any of these alleged broken devices, so > > it's hard to make progress on them. > > I don't have a sense of the scope either. But I could see BIOS not > enabling features that would provide no added power savings benefit. > We use ASPM to manage package power. There are Intel devices that > certainly don't require L1SS for the SoC to achieve the deepest > power savings. L1 alone is fine for them. I don't know what the test > coverage is for unenabled features. I've sent these questions to > our BIOS folks.
Once upon a time there was a push to make it so firmware only had to enumerate boot and console devices and it could skip enumeration and configuration of other devices. But I don't think we've made much progress on that, at least for x86, possibly because Linux depends so much on BIOS resource assignment. IMO that's a Linux deficiency.
Bjorn
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