David Howells | b920de1 | 2008-02-08 04:19:31 -0800 | [diff] [blame] | 1 | /* MN10300 Scatterlist definitions |
| 2 | * |
| 3 | * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd. |
| 4 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public Licence |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the Licence, or (at your option) any later version. |
| 10 | */ |
| 11 | #ifndef _ASM_SCATTERLIST_H |
| 12 | #define _ASM_SCATTERLIST_H |
| 13 | |
| 14 | #include <asm/types.h> |
| 15 | |
| 16 | /* |
| 17 | * Drivers must set either ->address or (preferred) page and ->offset |
| 18 | * to indicate where data must be transferred to/from. |
| 19 | * |
| 20 | * Using page is recommended since it handles highmem data as well as |
| 21 | * low mem. ->address is restricted to data which has a virtual mapping, and |
| 22 | * it will go away in the future. Updating to page can be automated very |
| 23 | * easily -- something like |
| 24 | * |
| 25 | * sg->address = some_ptr; |
| 26 | * |
| 27 | * can be rewritten as |
| 28 | * |
| 29 | * sg_set_page(virt_to_page(some_ptr)); |
| 30 | * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK; |
| 31 | * |
| 32 | * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens |
| 33 | */ |
| 34 | struct scatterlist { |
| 35 | #ifdef CONFIG_DEBUG_SG |
| 36 | unsigned long sg_magic; |
| 37 | #endif |
| 38 | unsigned long page_link; |
| 39 | unsigned int offset; /* for highmem, page offset */ |
| 40 | dma_addr_t dma_address; |
| 41 | unsigned int length; |
| 42 | }; |
| 43 | |
| 44 | #define ISA_DMA_THRESHOLD (0x00ffffff) |
| 45 | |
| 46 | #endif /* _ASM_SCATTERLIST_H */ |