tree 1d53810160229afde603c2e24939e852f7513986
parent 11251a869e84b2a3224955fe149dd33a16805cbf
author Bjorn Helgaas <bhelgaas@google.com> 1375740910 -0600
committer Bjorn Helgaas <bhelgaas@google.com> 1375740910 -0600

PCI: Align bridge I/O windows as required by downstream devices & bridges

An upstream bridge's I/O window must be at least as aligned as any
downstream device or bridge requires.  In particular, if the upstream
bridge supports 1K alignment but a downstream bridge requires 4K alignment,
the upstream window must also be 4K aligned.

Therefore, do not reduce the required alignment ("min_align") based on
the upstream bridge's capabilities.

Reported-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Suggested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>