for a PCI device during the boot-time probe of the parent PCI bus, then
zero the BAR and clear the resource list entry for that BAR. This forces
the PCI bus driver to request a valid resource range from the parent bridge
driver when the device driver tries to allocate the BAR. Similarly, if the
initial value of a BAR is a valid range but it is > 4GB and the current OS
only has 32-bit longs, then do a full teardown of the initial value of the
BAR to force a reallocation.
Reviewed by: imp
MFC after: 1 week
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