PCI: Check pref compatible bit for mem64 resource of PCIe device

PCI: Check pref compatible bit for mem64 resource of PCIe device

We still get "no compatible bridge window" warning on sparc T5-8
after we add support for 64bit resource parsing for root bus.

 PCI: scan_bus[/pci@300/pci@1/pci@0/pci@6] bus no 8
 PCI: Claiming 0000:00:01.0: Resource 15: 0000800100000000..00008004afffffff [220c]
 PCI: Claiming 0000:01:00.0: Resource 15: 0000800100000000..00008004afffffff [220c]
 PCI: Claiming 0000:02:04.0: Resource 15: 0000800100000000..000080012fffffff [220c]
 PCI: Claiming 0000:03:00.0: Resource 15: 0000800100000000..000080012fffffff [220c]
 PCI: Claiming 0000:04:06.0: Resource 14: 0000800100000000..000080010fffffff [220c]
 PCI: Claiming 0000:05:00.0: Resource 0: 0000800100000000..0000800100001fff [204]
 pci 0000:05:00.0: can't claim BAR 0 [mem 0x800100000000-0x800100001fff]: no compatible bridge window

All the bridges 64-bit resource have pref bit, but the device resource does not
have pref set, then we can not find parent for the device resource,
as we can not put non-pref mmio under pref mmio.

According to pcie spec errta
https://www.pcisig.com/specifications/pciexpress/base2/PCIe_Base_r2.1_Errata_08Jun10.pdf
page 13, in some case it is ok to mark some as pref.

Mark if the entire path from the host to the adapter is over PCI Express.
Set pref compatible bit for claim/sizing/assign for 64bit mem resource
on that pcie device.

-v2: set pref for mmio 64 when whole path is PCI Express, according to David Miller.
-v3: don't set pref directly, change to UNDER_PREF, and set PREF before
     sizing and assign resource, and cleart PREF afterwards. requested by BenH.
-v4: use on_all_pcie_path device flag instead.
-v6: update after pci_find_bus_resource() change

Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
Reported-by: David Ahern <david.ahern@oracle.com>
Tested-by: David Ahern <david.ahern@oracle.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81431
Tested-by: TJ <linux@iam.tj>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: sparclinux@vger.kernel.org
Orabug: 22855133

Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com>
(cherry picked from commit 44e098ad7113adb109fa2d95a29fe2ba9a846efd)
Signed-off-by: Allen Pais <allen.pais@oracle.com>