Re: [PATCH v2 14/14] powerpc/eeh: Move PE tree setup into the platform

["Oliver O'Halloran" <oohall@gmail.com>]

On Fri, Jul 24, 2020 at 3:01 PM Alexey Kardashevskiy <aik@ozlabs.ru> wrote:
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>
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> On 22/07/2020 14:26, Oliver O'Halloran wrote:
> > The EEH core has a concept of a "PE tree" to support PowerNV. The PE tree
> > follows the PCI bus structures because a reset asserted on an upstream
> > bridge will be propagated to the downstream bridges. On pseries there's a
> > 1-1 correspondence between what the guest sees are a PHB and a PE so the
> > "tree" is really just a single node.
> >
> > Current the EEH core is reponsible for setting up this PE tree which it
> > does by traversing the pci_dn tree. The structure of the pci_dn tree
> > matches the bus tree on PowerNV which leads to the PE tree being "correct"
> > this setup method doesn't make a whole lot of sense and it's actively
> > confusing for the pseries case where it doesn't really do anything.
> >
> > We want to remove the dependence on pci_dn anyway so this patch move
> > choosing where to insert a new PE into the platform code rather than
> > being part of the generic EEH code. For PowerNV this simplifies the
> > tree building logic and removes the use of pci_dn. For pseries we
> > keep the existing logic. I'm not really convinced it does anything
> > due to the 1-1 PE-to-PHB correspondence so every device under that
> > PHB should be in the same PE, but I'd rather not remove it entirely
> > until we've had a chance to look at it more deeply.
> >
> > Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
> > Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> > ---
> > v2: Reworked pseries PE setup slightly. NOT DONE YET. mostly done needs test
>
> So far it was looking good and now this :)
>
> When is it going to be done? Is this the broken stuff you mentioned
> elsewhere?

I am a dumb.

I put those in there to remind myself what I have / haven't done when
respinning a series. I added that before I tested it and forgot to
remove the comment.

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> --
> Alexey