1 /*
2 * MTD partitioning layer definitions
3 *
4 * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
5 *
6 * This code is GPL
7 */
8
9 #ifndef MTD_PARTITIONS_H
10 #define MTD_PARTITIONS_H
11
12 #include <linux/types.h>
13
14
15 /*
16 * Partition definition structure:
17 *
18 * An array of struct partition is passed along with a MTD object to
19 * mtd_device_register() to create them.
20 *
21 * For each partition, these fields are available:
22 * name: string that will be used to label the partition's MTD device.
23 * types: some partitions can be containers using specific format to describe
24 * embedded subpartitions / volumes. E.g. many home routers use "firmware"
25 * partition that contains at least kernel and rootfs. In such case an
26 * extra parser is needed that will detect these dynamic partitions and
27 * report them to the MTD subsystem. If set this property stores an array
28 * of parser names to use when looking for subpartitions.
29 * size: the partition size; if defined as MTDPART_SIZ_FULL, the partition
30 * will extend to the end of the master MTD device.
31 * offset: absolute starting position within the master MTD device; if
32 * defined as MTDPART_OFS_APPEND, the partition will start where the
33 * previous one ended; if MTDPART_OFS_NXTBLK, at the next erase block;
34 * if MTDPART_OFS_RETAIN, consume as much as possible, leaving size
35 * after the end of partition.
36 * mask_flags: contains flags that have to be masked (removed) from the
37 * master MTD flag set for the corresponding MTD partition.
38 * For example, to force a read-only partition, simply adding
39 * MTD_WRITEABLE to the mask_flags will do the trick.
40 *
41 * Note: writeable partitions require their size and offset be
42 * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
43 */
44
45 struct mtd_partition {
46 const char *name; /* identifier string */
47 const char *const *types; /* names of parsers to use if any */
48 uint64_t size; /* partition size */
49 uint64_t offset; /* offset within the master MTD space */
50 uint32_t mask_flags; /* master MTD flags to mask out for this partition */
51 struct device_node *of_node;
52 };
53
54 #define MTDPART_OFS_RETAIN (-3)
55 #define MTDPART_OFS_NXTBLK (-2)
56 #define MTDPART_OFS_APPEND (-1)
57 #define MTDPART_SIZ_FULL (0)
58
59
60 struct mtd_info;
61 struct device_node;
62
63 /**
64 * struct mtd_part_parser_data - used to pass data to MTD partition parsers.
65 * @origin: for RedBoot, start address of MTD device
66 */
67 struct mtd_part_parser_data {
68 unsigned long origin;
69 };
70
71
72 /*
73 * Functions dealing with the various ways of partitioning the space
74 */
75
76 struct mtd_part_parser {
77 struct list_head list;
78 struct module *owner;
79 const char *name;
80 const struct of_device_id *of_match_table;
81 int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
82 struct mtd_part_parser_data *);
83 void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
84 };
85
86 /* Container for passing around a set of parsed partitions */
87 struct mtd_partitions {
88 const struct mtd_partition *parts;
89 int nr_parts;
90 const struct mtd_part_parser *parser;
91 };
92
93 extern int __register_mtd_parser(struct mtd_part_parser *parser,
94 struct module *owner);
95 #define register_mtd_parser(parser) __register_mtd_parser(parser, THIS_MODULE)
96
97 extern void deregister_mtd_parser(struct mtd_part_parser *parser);
98
99 /*
100 * module_mtd_part_parser() - Helper macro for MTD partition parsers that don't
101 * do anything special in module init/exit. Each driver may only use this macro
102 * once, and calling it replaces module_init() and module_exit().
103 */
104 #define module_mtd_part_parser(__mtd_part_parser) \
105 module_driver(__mtd_part_parser, register_mtd_parser, \
106 deregister_mtd_parser)
107
108 int mtd_is_partition(const struct mtd_info *mtd);
109 int mtd_add_partition(struct mtd_info *master, const char *name,
110 long long offset, long long length);
111 int mtd_del_partition(struct mtd_info *master, int partno);
112 uint64_t mtd_get_device_size(const struct mtd_info *mtd);
113
114 #endif