MPC8343: PCI resource allocation questions

Luong Ngo at
Wed Oct 25 17:16:41 EST 2006

Would you mind explain me the last question in previous email?

  You are not leaving any memory space for any of the onchip devices,
the error messages are because the regions of memory that the devices
are expected to be at are already occupied by the PCI space.

Isn't it the PCI IO and PCI MEM space are separated from local memory space?
I think I see the global IO resource and MEM resource have the range of 0x0

Luong Ngo

On 10/24/06, Kumar Gala <galak at> wrote:
> > I'm a bit confused here. If the host bridge is ignored/excluded,
> > then the region size in BARs will not be allocated corresponding
> > resource by the PCI subsystem, then how would other PCI devices in
> > the slots could be allocated in the BAR's range? If I understand
> > correctly, the PCI devices's resources are allocated based on the
> > bridge resource, which is assigned statically by PCI subsystem
> > using hose->mem_space and hose->io_space instead of reading it from
> > the BARs. Maybe you are saying in the case the CPU is in agent mode
> > and its PCI host bridge is functioning as a PCI-PCI bridge?
> The problem is the host bridge shouldn't be included in BAR
> assignment since its the host bridge.  The problem is FSL devices
> show up when they scan themselves and the kernel then tries to
> allocate resources to them as if they were any other device.
> you are correct, the pci subsystem is setup via the hose structure
> and not by trying to read BARs on the host controller itself.
> - kumar
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