[PATCH v3 3/3] PCI: ARM: add support for generic PCI host controller

Will Deacon will.deacon at arm.com
Tue Feb 18 13:51:50 EST 2014


On Tue, Feb 18, 2014 at 06:47:15PM +0000, Arnd Bergmann wrote:
> On Tuesday 18 February 2014 18:44:20 Will Deacon wrote:
> > On Tue, Feb 18, 2014 at 06:21:42PM +0000, Jason Gunthorpe wrote:
> > > On Tue, Feb 18, 2014 at 12:20:43PM +0000, Will Deacon wrote:
> > > > +
> > > > +    // BUS_ADDRESS(3)  CPU_PHYSICAL(2)  SIZE(2)
> > > > +    ranges = <0x1000000 0x0 0x00000000  0x0 0x00000000  0x0 0x00010000>,
> > >                                            ^^^^^^^^^^^^^^
> > > 
> > > This probably shouldn't be 0 in the example, nor in your kvm tool
> > > output. For example purposes any value will do.
> > 
> > Hmm, so kvmtool actually provides a PC ioport at 0x0, which is handy since
> > there's an 8250 down there. That means we have:
> > 
> > 0x0    - 0x6200  : Weird PC stuff
> > 0x6200 - 0x10000 : PCI IO space
> > 
> > Should I just change everything to be offset by 0x6200?
> 
> Do you have a list of the stuff in there?

kvmtool provides an i8042, pci-shmem, an rtc, 8250 and vesa at the usual PC
offsets. On ARM, I regularly use the 8250 (there are even DT bindings for
it) and MarcZ got the rtc working for fun. Not tried the others though.

> If that is actually port I/O, leaving it in there may be best,
> but I agree the example should be changed.

Yup, it is port I/O. I'll make something up for the example.

Will



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