Re: [Patch V1 0/6] Refine generic/PCI MSI irqodmian interfaces

[Marc Zyngier]

On 13/11/14 11:43, Jiang Liu wrote:
> This patch set is based on tip/irq/irqdomain and tries to refine
> interfaces to support irqdomain for generic MSI and PCI MSI.
> 
> Patch 1 is just minor fixes for tip/irq/irqdomain.
> 
> Patch 2 introduces some helpers to hide struct msi_desc implementation
> details, so later we could move msi_list from struct pci_dev into
> struct device to enable generic MSI support.
> 
> Patch 3 introduces msi_domain_{alloc|free}_irqs() which generalize
> pci_msi_domain_alloc_irqs() to support generic MSI.
> 
> Patch 4 introduces default data structures and callback implementations
> to support msi_domain_alloc_irqs(), so reduce burden on generic MSI
> users.
> 
> Patch 5 converts PCI MSI to use generic MSI interfaces, and also
> implement default callbacks for PCI MSI.
> 
> Patch 6 introduces a mechanism to replace arch_setup_msi_irq()/
> arch_setup_msi_irqs()/arch_teardown_msi_irq()/arch_teardown_msi_irqs().
> 
> With this patch set applied, the generic MSI and PCI MSI interfaces
> are much easier to use. For extreme case, you only need to define
> a "struct msi_domain_info" and don't need to implement any callbacks,
> just using the default callbacks is OK:)
> 
> This patch set is also a preparation for:
> 1) Kill all weak functions in drivers/pci/msi.c
> 2) Implement support for non-PCI-compliant MSI device

I've rebased (once more!) the GICv3 ITS driver on top of this, and this
is definitely a major improvement. This is basically the first version
I can use without having to hack into the core code (apart from the
couple of nits I've mentioned earlier).

Now, Thomas' idea of putting the irq_domain close to the bus is very
appealing, and I've tweaked an earlier patch in order to do this: