[U-Boot] PCI on mpc832x?

[Joakim Tjernlund]

Kumar Gala <galak at kernel.crashing.org> wrote on 29/04/2009 14:35:19:
> 
> > I think I got the mapping of memory space now, thanks.
> >
> > A few questions though. I have noted that some boards map the PCI IO 
> > space
> > to 0x0 and some use the same address space as the CPU. If I use
> > the CPU address space as PCI IO space I get(in linux):
> >  PCI 0000:00 Cannot reserve Legacy IO [0x00-0xfff]
> > I don't understand what is best to do here, stay on 0x0 or move to CPU
> > address space?
> 
> PCI IO should normally be at 0 in the "PCI address space" and can be 
> at any CPU physical address.
> 
> > with  CONFIG_PCI_QUIRKS=y Linux prints:
> > PCI: Bus scan for 0000:00 returning with max=00
> > pci_bus 0000:00: resource 0 io:  [0x00-0xfffff]
> > pci_bus 0000:00: resource 1 mem: [0x80000000-0x8fffffff]
> > pci_bus 0000:00: resource 2 mem: [0x90000000-0x9fffffff]
> >
> > But if I turn off CONFIG_PCI_QUIRKS I get:
> > PCI: Bus scan for 0000:00 returning with max=00
> > PCI: Cannot allocate resource region 0 of device 0000:00:00.0, will 
> > remap
> > PCI: Cannot allocate resource region 2 of device 0000:00:00.0, will 
> > remap
> > pci 0000:00:00.0: BAR 2: got res [0x80000000-0x87ffffff] bus
> > [0x80000000-0x87ffffff] flags 0x2002120c
> > pci 0000:00:00.0: BAR 2: moved to bus [0x80000000-0x87ffffff] flags
> > 0x2120c
> > pci 0000:00:00.0: BAR 0: got res [0x90000000-0x901fffff] bus
> > [0x90000000-0x901fffff] flags 0x20020200
> > pci 0000:00:00.0: BAR 0: moved to bus [0x90000000-0x901fffff] flags
> > 0x20200
> > pci_bus 0000:00: resource 0 io:  [0x00-0xfffff]
> > pci_bus 0000:00: resource 1 mem: [0x80000000-0x8fffffff]
> > pci_bus 0000:00: resource 2 mem: [0x90000000-0x9fffffff]
> >
> > The BAR ... printout feels a bit off. Why do I need quirks on for
> > a clean boot?
> 
> Quirks are required for FSL based PCI controllers.  I know I've got a 
> change in current kernels to do:

I see. It is a pity though as:
size drivers/pci/quirks.o
   text    data     bss     dec     hex filename
  14130       8      20   14158    374e drivers/pci/quirks.o
adds almost 14KB code just for being able to use the FSL PCI controller.

            Jocke