[PATCH v2] PCI: mvebu - Support a bridge with no IO port window

[Bjorn Helgaas]

On Thu, Oct 31, 2013 at 10:48 AM, Jason Gunthorpe
<jgunthorpe at obsidianresearch.com> wrote:

> Indeed.. I was having problems here because linux was writing 0,0
> during discovery to the base,limit registers to 'disable' the IO
> window, which triggered a window allocation. So I re-read the PCI
> bridge spec (apparently too quickly) and decided 0,0 was OK, and it
> should be <=.
>
> However, looking again at the spec - it is very clear, < is the
> correct test, and when the values is equal a 4k window should be
> created.
>
> So, I wonder if there is a little bug in the Linux discovery code
> path, should it write FFFF,0 instead?

Sounds like a bug to me.  Do you want to fix it, or point me at it the
place where we write 0,0 so I can fix it?

Bjorn