soc/intel/common: Add _OSC method

Not masking any bits in Operating System Capabilities, which means we
support all the capabilities that OS passed in Arg3

Change-Id: Ib87915e18e305db41b52891ac5430201dda64bb5
Signed-off-by: Hannah Williams <hannah.williams@intel.com>
Reviewed-on: https://review.coreboot.org/15021
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

src/soc/intel/common/acpi/pci_osc.asl

@@ -0,0 +1,31 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2016 Intel Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define PCI_OSC_UUID "33DB4D5B-1FF7-401C-9657-7441C03DD766"
+
+Scope (\_SB.PCI0) {
+	Method (_OSC, 4) {
+		/* Check for proper GUID */
+		If (LEqual (Arg0, ToUUID (PCI_OSC_UUID))) {
+			/* Let OS control everything */
+			Return (Arg3)
+		} Else {
+			/* Unrecognized UUID */
+			CreateDWordField (Arg3, 0, CDW1)
+			Or (CDW1, 4, CDW1)
+			Return (Arg3)
+		}
+	}
+}