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 int (*parse_fn)(struct mtd_info *, const struct mtd_partition **, 81 struct mtd_part_parser_data *); 82 void (*cleanup)(const struct mtd_partition *pparts, int nr_parts); 83 }; 84 85 /* Container for passing around a set of parsed partitions */ 86 struct mtd_partitions { 87 const struct mtd_partition *parts; 88 int nr_parts; 89 const struct mtd_part_parser *parser; 90 }; 91 92 extern int __register_mtd_parser(struct mtd_part_parser *parser, 93 struct module *owner); 94 #define register_mtd_parser(parser) __register_mtd_parser(parser, THIS_MODULE) 95 96 extern void deregister_mtd_parser(struct mtd_part_parser *parser); 97 98 /* 99 * module_mtd_part_parser() - Helper macro for MTD partition parsers that don't 100 * do anything special in module init/exit. Each driver may only use this macro 101 * once, and calling it replaces module_init() and module_exit(). 102 */ 103 #define module_mtd_part_parser(__mtd_part_parser) \ 104 module_driver(__mtd_part_parser, register_mtd_parser, \ 105 deregister_mtd_parser) 106 107 int mtd_is_partition(const struct mtd_info *mtd); 108 int mtd_add_partition(struct mtd_info *master, const char *name, 109 long long offset, long long length); 110 int mtd_del_partition(struct mtd_info *master, int partno); 111 uint64_t mtd_get_device_size(const struct mtd_info *mtd); 112 113 #endif 114