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8d6a6a4763
This fixes a minor regression where broken PCI devices that use the
reserved "11" memory BAR type worked before e354597cce but not after.
The low four bits of a memory BAR are "PTT0" where P=1 for prefetchable
BARs, and TT is as follows:
00 32-bit BAR, anywhere in lower 4GB
01 anywhere below 1MB (reserved as of PCI 2.2)
10 64-bit BAR
11 reserved
Prior to e354597cce, we treated "0100" as a 64-bit BAR and all others,
including prefetchable 64-bit BARs ("1100") as 32-bit BARs. The e354597cce
fix, which appeared in 2.6.28, treats "x1x0" as 64-bit BARs, so the
reserved "x110" types are treated as 64-bit instead of 32-bit.
This patch returns to treating the reserved "11" type as a 32-bit BAR and
adds a warning if we see it.
It also logs a note if we see a 1M BAR. This is not a warning, because
such hardware conforms to pre-PCI 2.2 spec, but I think it's worth noting
because Linux ignores the 1M restriction if it ever has to assign the BAR.
CC: Peter Chubb <peterc@gelato.unsw.edu.au>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=35952
Reported-by: Jan Zwiegers <jan@radicalsystems.co.za>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>