[Skiboot] [PATCH skiboot] hw/phb3/naples: Disable D-states

[Alexey Kardashevskiy]

On 08/02/2019 16:33, David Gibson wrote:
> On Fri, Jan 11, 2019 at 03:06:52PM +1100, Alexey Kardashevskiy wrote:
>> Putting "Mellanox Technologies MT27700 Family [ConnectX-4] [15b3:1013]"
>> (more precisely, the second of 2 its PCI functions, no matter in what
>> order) into the D3 state causes EEH with the "PCT timeout" error.
>> This has been noticed on garrison machines only and firestones do not
>> seem to have this issue.
>>
>> This disables D-states changing for devices on root buses on Naples by
>> installing a config space access filter (copied from PHB4).
>>
>> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
> 
> While fixing this in firmware seems to make theoretical sense, from
> all I can tell it will take an awfully long time to get this merged
> into skiboot, built and rolled out to Garrison machines which need it.
> 
> I think we also need a kernel side workaround for this for the short
> to medium term.


Why not just have disable_idle_d3=1 in /etc/modprobe.d/xxx on garrisons?



-- 
Alexey