[RFC Part4 v1 00/17] Refine support of non-PCI-compliant Message

[Thomas Gleixner]

On Wed, 12 Nov 2014, Marc Zyngier wrote:
> This patch introduces two optionnal fields to the msi_chip structure:
> - a pointer to an irq domain, describing the MSI domain associated
>   with this msi_chip. To be populated with msi_create_irq_domain.
> - a domain_alloc_irqs() callback that has the same purpose as
>   arch_setup_msi_irqs(), with the above domain as an additional
>   parameter.
> 
> If both of these fields are non-NULL, then domain_alloc_irqs() is
> called, bypassing the setup_irq callback. This allows the MSI driver
> to use the domain stacking feature without mandating core support in
> the architecture.

I'd rather have the callback in the irqdomain itself. Along with a
callback to free the interrupts.

AFAICT is msi_chip more or less a wrapper around the actual MSI irq
domain. So we rather move towards assigning irqdomain to the pci bus
and get rid of msi_chip instead of adding another level of obscure
indirection through msi_chip.

Thanks,

	tglx