[PATCH 2/2] cxl: Set VPD timeout to avoid access failures

[Frederic Barrat]

Le 21/11/2016 à 22:10, Matthew R. Ochs a écrit :
> Some IBM CXL devices can take up to ~120ms to complete a VPD access
> transaction when under heavy load. With an existing default VPD timeout
> of 50ms, reads/writes can fail despite there not being an issue with the
> underlying hardware.
>
> To avoid these false failures, increase the VPD wait timeout for certain
> CXL devices to a value that allows appropriate VPD access delay when faced
> with a worst-case scenario.
>
> Signed-off-by: Matthew R. Ochs <mrochs at linux.vnet.ibm.com>
> ---

If the new pci API gets in, then I'm ok with the cxl change, at least 
for now. For longer term, we should consider opening up the cxl kernel 
API to give access to the new pci API so that it can be tuned by the AFU 
driver directly, since it would know better than cxl what the proper vpd 
access timeout should be.

Acked-by: Frederic Barrat <fbarrat at linux.vnet.ibm.com>

   Fred