x86: Fix boot on Twinhead H12Y
Alan Cox [Tue, 15 May 2012 17:44:15 +0000 (18:44 +0100)]
Despite lots of investigation into why this is needed we don't
know or have an elegant cure. The only answer found on this
laptop is to mark a problem region as used so that Linux doesn't
put anything there.

Currently all the users add reserve= command lines and anyone
not knowing this needs to find the magic page that documents it.
Automate it instead.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Tested-and-bugfixed-by: Arne Fitzenreiter <arne@fitzenreiter.de>
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=10231
Link: http://lkml.kernel.org/r/20120515174347.5109.94551.stgit@bluebook
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/pci/fixup.c

index d0e6e40..5dd467b 100644 (file)
@@ -519,3 +519,20 @@ static void sb600_disable_hpet_bar(struct pci_dev *dev)
        }
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_ATI, 0x4385, sb600_disable_hpet_bar);
+
+/*
+ * Twinhead H12Y needs us to block out a region otherwise we map devices
+ * there and any access kills the box.
+ *
+ *   See: https://bugzilla.kernel.org/show_bug.cgi?id=10231
+ *
+ * Match off the LPC and svid/sdid (older kernels lose the bridge subvendor)
+ */
+static void __devinit twinhead_reserve_killing_zone(struct pci_dev *dev)
+{
+        if (dev->subsystem_vendor == 0x14FF && dev->subsystem_device == 0xA003) {
+                pr_info("Reserving memory on Twinhead H12Y\n");
+                request_mem_region(0xFFB00000, 0x100000, "twinhead");
+        }
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x27B9, twinhead_reserve_killing_zone);