sandbox: Add asm/cache.h for sandbox

This file is required by the new DMA buffer alignment macro.

Signed-off-by: Anton Staaf <robotboy@chromium.org>
Cc: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>

arch/sandbox/include/asm/cache.h

+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __SANDBOX_CACHE_H__
+#define __SANDBOX_CACHE_H__
+
+/*
+ * For native compilation of the sandbox we should still align
+ * the contents of stack buffers to something reasonable.  The
+ * GCC macro __BIGGEST_ALIGNMENT__ is defined to be the maximum
+ * required alignment for any basic type.  This seems reasonable.
+ */
+#define ARCH_DMA_MINALIGN	__BIGGEST_ALIGNMENT__
+
+#endif /* __SANDBOX_CACHE_H__ */