[Skiboot] [PATCH v2] phb4: Reset pfir and nfir if new errors reported during ETU reset

[Vasant Hegde]

On 09/17/2018 12:55 PM, Vaibhav Jain wrote:
> During fast-reboot new PEC errors can be latched even after ETU-Reset
> is asserted. This will result in values of variables nfir_cache and
> pfir_cache to be out of sync.
> 
> During step-2 of CRESET nfir_cache and pfir_cache values are used to
> bring the PHB out of reset state. However if these variables are out
> as noted above of date the nfir/pfir registers are never reset
> completely and ETU still remains frozen.
> 
> Hence this patch updates step-2 of phb4_creset to re-read the values of
> nfir/pfir registers to check if any new errors were reported after
> ETU-reset was asserted, report these new errors and reset the
> nfir/pfir registers. This should bring the ETU out of reset
> successfully.
> 
> Signed-off-by: Vaibhav Jain <vaibhav at linux.ibm.com>

Tested-By: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>

-Vasant