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Subject: Re: [RFC/PATCH 0/16] Ops based MSI Implementation
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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> Anyway for architecture hooks I have it down to just:
> /*
>  * The arch hook for setup up msi irqs
>  */
> int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);
> void arch_teardown_msi_irq(unsigned int irq);

Which we would have to turn into "ops" hooks right away on powerpc
anyway because we can have multiple implementations in a given kernel
image depending on a mix of platform and which bus the devie is on.

> Which should be good enough to handle everything but RTAS.

You keep ignoring the problem then... we -HAVE- to handle the RTAS case.
In addition, it's not unlikely that other virtualized environment will
provide a similar very high level APIs to MSIs.

Ben.