[PATCH v4 1/2] PCI: add AMD PCIe quirk for nvme shutdown opt

[Christoph Hellwig]

A cover letter for the series would be really nice.

On Thu, Apr 15, 2021 at 11:52:04AM +0800, Prike Liang wrote:
> The NVME device pluged in some AMD PCIE root port will resume timeout
> from s2idle which caused by NVME power CFG lost in the SMU FW restore.
> This issue can be workaround by using PCIe power set with simple
> suspend/resume process path instead of APST. In the onwards ASIC will
> try do the NVME shutdown save and restore in the BIOS and still need PCIe
> power setting to resume from RTD3 for s2idle.
> 
> In this preparation patch add a PCIe quirk for the AMD.

The above looks very hard to understand to me.  It uses some AMD
specific terms, and also is overly specific to NVMe.  Any other PCIe
device not doing a runtime-D3 in these slots will have the same problem.

So I think you should generalize the flag name and description to
describe what broken behavior the AMD root port has here, and only
cursory refer to drivers that are broken by it.

I'd also much prefer if the flag is used on every pci_dev that is
affected by the broken behavior rather than requiring another lookup
in the driver.