[PATCH] nvme/pci: default to simple suspend

[Christoph Hellwig]

On Mon, Feb 07, 2022 at 08:06:55AM -0800, Keith Busch wrote:
> > I'd really prefer to sort this out at the platform level.  We can't work
> > around broken platforms in nvme forever.
> 
> I agree, but I'm not sure how to get everyone aligned.
> 
> How about this to resolve the regressions: if the platform doesn't
> provide StorageD3Enable property, can we just default to the simple
> shutdown method? We'd only use the nvme power management capabilities if
> the platform explicity says it doesn't want D3, making the default the
> same as the legacy behavior.

I don't think this will work, as most older platforms just won't have
that attribute at all, and non-ACPI platforms most certainly won't have
it.  We'll need more quirks in the core PCI/PM code like we did for the
AMD mobile platforms.