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

[Jiang Liu <jiang.liu@linux.intel.com>]

On 2014/11/14 22:11, Yijing Wang wrote:
> 
> 在 2014/11/14 9:39, Jiang Liu 写道:
>> On 2014/11/14 9:31, Thomas Gleixner wrote:
>>> On Fri, 14 Nov 2014, Yijing Wang wrote:
>>>
>> Hi Thomas,
>>     So we need something like:
>> struct msi_chip *pci_get_msi_chip(struct pci_dev *);
>> or:
>> struct irq_domain *pci_get_msi_domain(struct pci_dev *);
> 
> Hi Gerry,
> what about associate the platform specific  struct msi_chip
> *pci_get_msi_chip(struct pci_dev *)
> with struct pci_host_bridge. we could provide the private
> "pci_get_msi_chip()" in the PCI
> host drivers.
Hi Yijing,
	Still need some time to dig into msi_chip related code.
When refining the PCI MSI code, I feel the best way is:
1) Every PCI device is associated with an PCI MSI irqdomain.
2) PCI MSI core directly talks to irqdomain to allocate/free
   interrupts.
3) Kill all weak functions in pci/drivers/msi.c.
4) Kill struct msi_chip.

We have achieved 1 and 2. And seems we could also achieve 3 by
converting all arch specific PCI MSI code to use hierarchy
irqdomain. But not sure whether we could achieve 4, not familiar
with ARM world:)

On x86, we could kill all PCI MSI weak function after converting
Xen to irqdomain. I think we may have a prototype for x86 in next
week.
Thanks!
Gerry