PCI: Fix Intel ACS quirk UPDCR register address
authorSteffen Liebergeld <steffen.liebergeld@kernkonzept.com>
Wed, 18 Sep 2019 13:16:52 +0000 (15:16 +0200)
committerBjorn Helgaas <bhelgaas@google.com>
Tue, 15 Oct 2019 21:39:11 +0000 (16:39 -0500)
commitd8558ac8c93d429d65d7490b512a3a67e559d0d4
treed73f11c7052990f341fb0c44d8d1c3ea0361cc6a
parentfef2dd8b3966517172514ea5a89104ba7745678b
PCI: Fix Intel ACS quirk UPDCR register address

According to documentation [0] the correct offset for the Upstream Peer
Decode Configuration Register (UPDCR) is 0x1014.  It was previously defined
as 0x1114.

d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports")
intended to enforce isolation between PCI devices allowing them to be put
into separate IOMMU groups.  Due to the wrong register offset the intended
isolation was not fully enforced.  This is fixed with this patch.

Please note that I did not test this patch because I have no hardware that
implements this register.

[0] https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/4th-gen-core-family-mobile-i-o-datasheet.pdf (page 325)
Fixes: d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports")
Link: https://lore.kernel.org/r/7a3505df-79ba-8a28-464c-88b83eefffa6@kernkonzept.com
Signed-off-by: Steffen Liebergeld <steffen.liebergeld@kernkonzept.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org # v3.15+
drivers/pci/quirks.c