Messages in this thread | | | Date | Fri, 28 Aug 2015 21:39:49 +0000 (UTC) | From | Keith Busch <> | Subject | Re: [RFC PATCH 1/2] x86: PCI bus specific MSI operations |
| |
On Fri, 28 Aug 2015, Thomas Gleixner wrote: > On Thu, 27 Aug 2015, Keith Busch wrote: > >> This patch adds struct x86_msi_ops to x86's PCI sysdata. This gives a >> host bridge driver the option to provide alternate MSI Data Register >> and MSI-X Table Entry programming for devices in PCI domains that do >> not subscribe to usual "IOAPIC" format. > > I'm not too fond about more ad hoc indirection and special casing. We > should be able to handle this with hierarchical irq domains. Jiang > might have an idea how to do that for your case.
Thank you for the suggestion, I will take a closer look at this again. All the better if we don't require an arch specific dependency.
I asked Jiang about domain hierarchies a few weeks ago and understood these are suited for irq controllers, but the VMD device is an aggregator.
Here's a little more h/w info in case it helps steer me in the right direction: VMD muxes all the device interrupts in its PCI domain into one of several VMD h/w irqs. The VMD driver then has to de-mux that into CPU side irqs for each device.
| |