[PATCH v2] powerpc/powernv: Add pci_reset_phbs parameter to issue a PHB reset

[Balbir Singh]

On Thu, Oct 26, 2017 at 2:27 AM, Guilherme G. Piccoli
<gpiccoli at linux.vnet.ibm.com> wrote:
> During a kdump kernel boot in PowerPC, we request a reset of the PHBs
> to the FW. It makes sense, since if we are booting a kdump kernel it
> means we had some trouble before and we cannot rely in the adapters'
> health; they could be in a bad state, hence the reset is needed.
>
> But this reset is useful not only in kdump - there are situations,
> specially when debugging drivers, that we could break an adapter in
> a way it requires such reset. One can tell to just go ahead and
> reboot the machine, but happens that many times doing kexec is much
> faster, and so preferable than a full power cycle.
>
> This patch adds the pci_reset_phbs parameter to perform such reset
> when desired by the user.
>

Do we care to reset specific phbs or all of them? I guess all based on
your description.

Balbir Singh.