Currently the functions in pci-spapr.c (like pci-pc.c on which it's based)
don't distinguish between 32-bit and 64-bit PCI MMIO. At the moment, the
qemu side implementation is a bit weird and has a single MMIO window
straddling 32-bit and 64-bit regions, but we're likely to change that in
future.
In any case, pci-pc.c - and therefore the testcases using PCI - only handle
32-bit MMIOs for now. For spapr despite whatever changes might happen with
the MMIO windows, the 32-bit window is likely to remain at 2..4 GiB in PCI
space.
So, explicitly limit pci-spapr.c to 32-bit MMIOs for now, we can add 64-bit
MMIO support back in when and if we need it.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
In pci-spapr.c (as in pci-pc.c from which it was derived), the
pci_hole_start/pci_hole_size and pci_iohole_start/pci_iohole_size pairs[1]
essentially define the region of PCI (not CPU) addresses in which MMIO
or PIO BARs respectively will be allocated.
The size value is relative to the start value. But in pci-spapr.c it is
set to the entire size of the window supported by the (emulated) hardware,
but the start values are *not* at the beginning of the emulated windows.
That means if you tried to map enough PCI BARs, we'd messily overrun the
IO windows, instead of failing in iomap as we should.
This patch corrects this by calculating the hole sizes from the location
of the window in PCI space and the hole start.
[1] Those are bad names, but that's a problem for another time.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
The libqos code for accessing PCI on the spapr machine type uses IOBASE()
and MMIOBASE() macros to determine the address in the CPU memory map of
the windows to PCI address space.
This is a detail of the implementation of PCI in the machine type, it's not
specified by the PAPR standard. Real guests would get the addresses of the
PCI windows from the device tree.
Finding the device tree in libqos would be awkward, but we can at least
localize this knowledge of the implementation to the init function, saving
it in the QPCIBusSPAPR structure for use by the accessors.
That leaves only one place to fix if we alter the location of the PCI
windows, as we're planning to do.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
[dwg: Fixed build problem on 32-bit hosts]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>