Re: Purpose of pci_remap_iospace

From: Lorenzo Pieralisi
Date: Thu Jul 14 2016 - 11:26:22 EST


On Thu, Jul 14, 2016 at 05:12:01PM +0200, Arnd Bergmann wrote:
> On Thursday, July 14, 2016 3:56:24 PM CEST Lorenzo Pieralisi wrote:
> > On Thu, Jul 14, 2016 at 01:32:13PM +0000, Bharat Kumar Gogada wrote:
> >
> > [...]
> >
> > > Hi Lorenzo,
> > >
> > > I missed something in my device tree now I corrected it.
> > >
> > > ranges = <0x01000000 0x00000000 0xe0000000 0x00000000 0xe0000000 0 0x00010000 //io
> >
> > You have not missed anything, you changed the PCI bus address at
> > which your host bridge responds to IO space and it must match
> > your configuration.
>
> I'd always recommend mapping the I/O space to PCI address zero, but
> evidently the hardware is not configured that way here.

+1 and it is a message that must be heeded by Xiling folks before
merging the host controller changes and respective DT bindings/dts.

Lorenzo