Re: [PATCH] PCI: Disable D3cold on Asus B1400 PCI-NVMe bridge

From: Daniel Drake
Date: Tue Jan 30 2024 - 14:01:45 EST


On Tue, Jan 30, 2024 at 2:47 PM Mario Limonciello
<mario.limonciello@xxxxxxx> wrote:
> Has there already been a check done whether any newer firmware is
> available from ASUS that doesn't suffer the deficiency described below?

The latest firmware does flip StorageD3Enable to 0, which has the side
effect of never putting the NVMe device or the parent bridge into
D3cold.
However, we have shipped hundreds of these devices with the original
production BIOS version to first time computer users, so it is not
feasible to ask the end user to upgrade. And there is no
Linux-compatible online firmware update for this product range. Hence
a Linux-level workaround for this issue would be highly valuable.

> Is this the only problem blocking s2idle from working effectively on
> this platform? If so, I would think you want to just do the revert in
> the same series if it's decided this patch needs to spin again for any
> reason.

Yes these could be combined into the same series, with agreement from
the drivers/acpi/ maintainers for the S3 revert.

Thanks
Daniel