Re: [PATCH v8 3/9] pci: Introduce pci_register_io_range() helper function.

From: Arnd Bergmann
Date: Wed Jul 09 2014 - 02:25:58 EST

On Tuesday 08 July 2014, Liviu Dudau wrote:
> > Here's what these look like in /proc/iomem and /proc/ioports (note that
> > there are two resource structs for each memory-mapped IO port space: one
> > IORESOURCE_MEM for the memory-mapped area (used only by the host bridge
> > driver), and one IORESOURCE_IO for the I/O port space (this becomes the
> > parent of a region used by a regular device driver):
> >
> > /proc/iomem:
> > PCI Bus 0000:00 I/O Ports 00000000-00000fff
> > PCI Bus 0001:00 I/O Ports 01000000-01000fff
> >
> > /proc/ioports:
> > 00000000-00000fff : PCI Bus 0000:00
> > 01000000-01000fff : PCI Bus 0001:00
> OK, I have a question that might be ovbious to you but I have missed the answer
> so far: how does the IORESOURCE_MEM area gets created? Is it the host bridge
> driver's job to do it? Is it something that the framework should do when it
> notices that the IORESOURCE_IO is memory mapped?

The host bridge driver should either register the IORESOURCE_MEM resource
itself from its probe or setup function, or it should get registered behind
the covers in drivers using of_create_pci_host_bridge().

Your new pci_host_bridge_of_get_ranges already loops over all the
resources, so it would be a good place to put that.

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