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+/* MN10300 Scatterlist definitions
+ *
+ * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_SCATTERLIST_H
+#define _ASM_SCATTERLIST_H
+
+#include <asm/types.h>
+
+/*
+ * Drivers must set either ->address or (preferred) page and ->offset
+ * to indicate where data must be transferred to/from.
+ *
+ * Using page is recommended since it handles highmem data as well as
+ * low mem. ->address is restricted to data which has a virtual mapping, and
+ * it will go away in the future. Updating to page can be automated very
+ * easily -- something like
+ *
+ * sg->address = some_ptr;
+ *
+ * can be rewritten as
+ *
+ * sg_set_page(virt_to_page(some_ptr));
+ * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;
+ *
+ * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
+ */
+struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
+ unsigned long page_link;
+ unsigned int offset; /* for highmem, page offset */
+ dma_addr_t dma_address;
+ unsigned int length;
+};
+
+#define ISA_DMA_THRESHOLD (0x00ffffff)
+
+#endif /* _ASM_SCATTERLIST_H */