Re: [PATCH v4 2/2] PCI: Enable NO_BUS_RESET quirk for Nvidia GPUs

From: Shanker R Donthineni
Date: Wed May 05 2021 - 16:04:31 EST


Thanks Alex for the detailed explanation.

On 5/5/21 2:13 PM, Alex Williamson wrote:
> I'm also assuming all SoCs integrating this GPU will provide a
> _RST method, but we're also disabling SBR in this series to avoid the
> only other generic reset option we'd have for this device.
All the platforms/SoCs which contain these GPUs will provide ACPI/firmware with
_RST method.
 
> In the more general case, I'd expect that system firmware isn't going
> to implement an _RST method for a pluggable slot, so we'll lookup the
> ACPI handle, fail to find a _RST method and drop to the next option.
> For a PCI/e slot, at best the _RST method might be included in the _PRR
> scope rather than the device scope to indicate it affects the entire
> slot. That could be something like the #PERST below or a warm reset. I
> don't think we're enabling that here, are we?
No, our_RST method will be included only in a device context (not _PRP).