emulation/qemu-power8: initial mainboard and arch commit

This builds and produces an image.

The next step is to get a 'halt' instruction into the boot block and then attach with qemu.

I can't get the powerpc64le-linux-gnu-ld.bfd to recognize any output arch but
powerpc. That makes no sense to me.

Change-Id: Ia2a5fe07a1457e7b6974ab1473539c7447d7a449
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/13704
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

src/mainboard/emulation/qemu-power8/cbmem.c

@@ -0,0 +1,25 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#include <cbmem.h>
+
+void *cbmem_top(void)
+{
+	/* Top of cbmem is at lowest usable DRAM address below 4GiB. */
+	/* For now, last 1M of 4G */
+	void *ptr = (void *) ((1ULL << 32) - 1048576);
+	return ptr;
+}
+