chromeos: provide option to dynamically allocate ram oops buffer

Fixing the location of the ram oops buffer can lead to certain
kernel and boot loaders being confused when there is a ram
reservation low in the address space. Alternatively provide
a mechanism to allocate the ram oops buffer in cbmem. As cbmem
is usually high in the address space it avoids low reservation
confusion.

The patch uncondtionally provides a GOOG9999 ACPI device with
a single memory resource describing the memory region used for
the ramoops region.

BUG=None
BRANCH=baytrail,haswell
TEST=Built and booted with and w/o dynamic ram oops. With
     the corresponding kernel change things behave correctly.

Change-Id: Ide2bb4434768c9f9b90e125adae4324cb1d2d073
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/5257
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

3 files changed, 48 insertions, 1 deletions

diff --git a/src/vendorcode/google/chromeos/acpi/chromeos.asl b/src/vendorcode/google/chromeos/acpi/chromeos.asl
index 278296c939..8f63f122d5 100644
--- a/src/vendorcode/google/chromeos/acpi/chromeos.asl
+++ b/src/vendorcode/google/chromeos/acpi/chromeos.asl
@@ -107,3 +107,5 @@ Device (CRHW)
 		Return (TSLM)
 	}
 }
+
+#include "ramoops.asl"
diff --git a/src/vendorcode/google/chromeos/acpi/gnvs.asl b/src/vendorcode/google/chromeos/acpi/gnvs.asl
index dc4a0bfbe8..5377a8540f 100644
--- a/src/vendorcode/google/chromeos/acpi/gnvs.asl
+++ b/src/vendorcode/google/chromeos/acpi/gnvs.asl
@@ -34,4 +34,6 @@ VBT9,   32,	// 0x196 - FMAP base address
 CHVD, 24576,	// 0x19a - VDAT space filled by verified boot
 VBTA,	32,	// 0xd9a - pointer to smbios FWID
 MEHH,  256,	// 0xd9e - Management Engine Hash
-		// 0xdbe
+RMOB,   32,	// 0xdbe - RAM oops base address
+RMOL,   32,	// 0xdc2 - RAM oops length
+		// 0xdc6
diff --git a/src/vendorcode/google/chromeos/acpi/ramoops.asl b/src/vendorcode/google/chromeos/acpi/ramoops.asl
new file mode 100644
index 0000000000..e43548933f
--- /dev/null
+++ b/src/vendorcode/google/chromeos/acpi/ramoops.asl
@@ -0,0 +1,43 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+Scope (\_SB)
+{
+	Device(RMOP)
+	{
+		Name (_HID, "GOOG9999")
+		Name (_CID, "GOOG9999")
+		Name (_UID, 1)
+
+		Name (RBUF, ResourceTemplate()
+		{
+			Memory32Fixed (ReadWrite, 0, 0, MRES)
+		})
+
+		Method (_CRS)
+		{
+			CreateDwordField (^RBUF, ^MRES._BAS, RBAS)
+			CreateDwordField (^RBUF, ^MRES._LEN, RLEN)
+			Store (\RMOB, RBAS)
+			Store (\RMOL, RLEN)
+			Return (^RBUF)
+		}
+	}
+}