[PATCH 5/6] arm64, defconfig: Enable PCI
arnd at arndb.de
Wed Sep 24 11:40:18 PDT 2014
On Wednesday 24 September 2014 18:10:48 Catalin Marinas wrote:
> On Wed, Sep 24, 2014 at 05:26:31PM +0100, Robert Richter wrote:
> > On 24.09.14 18:14:11, Arnd Bergmann wrote:
> > > On Wednesday 24 September 2014 17:37:47 Robert Richter wrote:
> > > > config PCI
> > > > bool "PCI support"
> > > > + default y
> > > > help
> > > > This feature enables support for PCIe bus system. If you say Y
> > > > here, the kernel will include drivers and infrastructure code
> > > > to support PCIe bus devices.
> > > >
> > > > +config PCI_MSI
> > > > + def_bool PCI
> > > > +
> > > > config PCI_DOMAINS
> > > > def_bool PCI
> > >
> > > There is already a PCI_MSI symbol in drivers/pci/Kconfig. Just select that
> > > from the PCI symbol above rather than defining a second one.
> > The intention is not to have a second definition, instead this should
> > enable the default value just for arm64. Thus I put it to
> > arch/arm64/Kconfig. Otherwise it would be enabled per default on all
> > archs.
I don't think other architectures actually see the PCI symbol that is
defined in the arm64 Kconfig file, but I might be wrong.
> > We could have used select in config ARM64, but I tried to avoid using
> > select due to the dependency issue and instead implement this with
> > default-y/depends-on. Doing so it can be manually disabled too.
How about adding a new symbol like
> It may be better to simply set PCI and PCI_MSI as defaults in defconfig
> rather than "default y" and an additional config PCI_MSI entry.
Selecting PCI_MSI unconditionally seems fine to me. We won't have any
ARM64 systems that only do classic PCI, and MSI is mandatory for PCIe.
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