On Tuesday 11 December 2012, Thomas Petazzoni wrote:
> On Tue, 11 Dec 2012 10:43:49 +0000, Arnd Bergmann wrote:
> > On Friday 07 December 2012, Thomas Petazzoni wrote:
> > > The pcim_*() functions are used by the libata-sff subsystem, and this
> > > subsystem is used for many SATA drivers on ARM platforms that do not
> > > necessarily have I/O ports.
> >
> > I think this one is wrong as the CONFIG_HAS_IOPORT does not refer to the
> > presence of PIO ports but to whether or not they provide an ioport_map
> > function. If there is no ioport_map(), devm_pci_iomap will fail to link
> > as far as I can tell.
>
> The problem is that on ARCH_MULTI_V7, ARCH_VEXPRESS is forcefully
> enabled. And ARCH_VEXPRESS selects NO_IOPORT.. so you don't have the
> pcim_*() functions, and therefore libata-sff.c (needed for many SATA
> drivers) will not build. How do you solve this?
What you describe here are probable two bugs, and we should fix both:
* ARCH_VEXPRESS should not select NO_IOPORT. It's generally wrong
to select this in combination with ARCH_MULTIPLATFORM, when some
of the other platforms you may enable actually have IOPORT mapping
support.
* We should not unconditionally select ARCH_VEXPRESS from ARCH_MULTIPLATFORM.
There is no reason why we would enable that platform for building
a kernel that runs on only one other platform.
> I'm not sure which devm_pci_iomap() you're referring to since my patch
> makes only the pcim_iomap_table(), pcim_iomap(), pcim_iounmap(),
> pcim_iomap_regions(), pcim_iomap_regions_request_all() and
> pcim_iounmap_regions() available under CONFIG_PCI instead of CONFIG_PCI
> && CONFIG_HAS_IOPORT.
Sorry, I meant pcim_iomap.
> So maybe you were referring to pcim_iomap(). I haven't checked in
> details, but I guess it builds because ioport_map() is implemented in
> arch/arm/mm/iomap.c.
Right. If an ioport_map function is provided for a given platform,
we should also set HAVE_IOPORT and vice versa. This is probably
fallout of the io.h conversion for multiplatform.
Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
