INTRNG (Was: svn commit: r301453....)

[Andrew Turner]

On Fri, 12 Aug 2016 08:31:06 -0700
Nathan Whitehorn <nwhitehorn at freebsd.org> wrote:
> One other non-urgent question about PCI code:
> 
> There's a new function ofw_bus_msimap() that does not seem to
> implement any particular part of any real binding standard. There's
> a .txt file in the device-tree repo, but many (most?, all?) PCI
> bridges don't seem to implement MSI that way. This is out-of-scope
> for the immediate discussion, but it would be good to fix later. If
> there are indeed only a handful of bridges that do MSI that way, it
> should probably be moved into the PCI bridge drivers that do use it.

The ofw_bus_msimap() implements the standard FDT MSI properties to
find the needed MSI/MSI-X controller. See [1] for the binding document.

> 
> Similarly, dev/pci/pci_host_generic.c isn't actually generic and is 
> instead a driver for some particular ARM bridges. It should be moved
> at some point under sys/arm. Most of the code in it also duplicates 
> dev/ofw/ofwpci.c (but with some added bugs in handling the "ranges" 
> property).

I don't see why. There is nothing ARM specific in it. I also have
patches to use it with ACPI as the existing driver makes assumptions
about PCI that may not be true on all platforms.

Andrew

[1]
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/pci/pci-msi.txt