tree a1a3c26594f6a590a0b189334f93bc280d0d6373
parent 6756093252d7e9971da15460205285a7dcd8222c
author Yinghai Lu <yinghai@kernel.org> 1347945933 -0700
committer Yinghai Lu <yinghai@kernel.org> 1347945933 -0700

PCI: Try to allocate mem64 above 4G at first

Will fall back to below 4g if it can not find any above 4g.

x86 32bit without X86_PAE support will have bottom set to 0, because
resource_size_t is 32bit.

Also for 32bit with resource_size_t 64bit kernel on machine with pae support
we are safe because iomem_resource is limited to 32bit according to
x86_phys_bits.

-v2: update bottom assigning to make it clear for non-pae support machine.
-v3: Bjorn's change:
        use MAX_REOURCE instead of -1
        use start/end instead of bottom/max
        for all arch instead of just x86_64
-v4: updated after PCI_MAX_RESOURCE_32 change.
-v5: restore io handling to use PCI_MAX_RESOURCE_32 as limit.
-v6: checking pcibios_resource_to_bus return for every bus res, to decide it
	if we need to try high at first.
     It supports all arches instead of just x86_64.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>