1 /*
2  * Copyright (c) 2017-2024 Nordic Semiconductor ASA
3  * Copyright (c) 2015 Runtime Inc
4  * Copyright (c) 2023 Sensorfy B.V.
5  *
6  * SPDX-License-Identifier: Apache-2.0
7  */
8 
9 /**
10  * @file
11  * @brief Public API for flash map
12  */
13 
14 #ifndef ZEPHYR_INCLUDE_STORAGE_FLASH_MAP_H_
15 #define ZEPHYR_INCLUDE_STORAGE_FLASH_MAP_H_
16 
17 /**
18  * @brief Abstraction over flash partitions/areas and their drivers
19  *
20  * @defgroup flash_area_api flash area Interface
21  * @since 1.11
22  * @version 1.0.0
23  * @ingroup storage_apis
24  * @{
25  */
26 
27 /*
28  * This API makes it possible to operate on flash areas easily and
29  * effectively.
30  *
31  * The system contains global data about flash areas. Every area
32  * contains an ID number, offset, and length.
33  */
34 
35 /**
36  *
37  */
38 #include <zephyr/types.h>
39 #include <stddef.h>
40 #include <sys/types.h>
41 #include <zephyr/device.h>
42 #include <zephyr/devicetree.h>
43 
44 #ifdef __cplusplus
45 extern "C" {
46 #endif
47 
48 /**
49  * @brief Flash partition
50  *
51  * This structure represents a fixed-size partition on a flash device.
52  * Each partition contains one or more flash sectors.
53  */
54 struct flash_area {
55 	/** ID number */
56 	uint8_t fa_id;
57 	uint16_t pad16;
58 	/** Start offset from the beginning of the flash device */
59 	off_t fa_off;
60 	/** Total size */
61 	size_t fa_size;
62 	/** Backing flash device */
63 	const struct device *fa_dev;
64 #if CONFIG_FLASH_MAP_LABELS
65 	/** Partition label if defined in DTS. Otherwise nullptr; */
66 	const char *fa_label;
67 #endif
68 };
69 
70 /**
71  * @brief Structure for transfer flash sector boundaries
72  *
73  * This template is used for presentation of flash memory structure. It
74  * consumes much less RAM than @ref flash_area
75  */
76 struct flash_sector {
77 	/** Sector offset from the beginning of the flash device */
78 	off_t fs_off;
79 	/** Sector size in bytes */
80 	size_t fs_size;
81 };
82 
83 #if defined(CONFIG_FLASH_AREA_CHECK_INTEGRITY)
84 /**
85  * @brief Structure for verify flash region integrity
86  *
87  * This is used to pass data to be used to check flash integrity using SHA-256
88  * algorithm.
89  */
90 struct flash_area_check {
91 	const uint8_t *match;		/** 256 bits match vector */
92 	size_t clen;			/** Content len to be compared */
93 	size_t off;			/** Start Offset */
94 	uint8_t *rbuf;			/** Temporary read buffer  */
95 	size_t rblen;			/** Size of read buffer */
96 };
97 
98 /**
99  * Verify flash memory length bytes integrity from a flash area. The start
100  * point is indicated by an offset value.
101  *
102  * @param[in] fa	Flash area
103  * @param[in] fic	Flash area check integrity data
104  *
105  * @return  0 on success, negative errno code on fail
106  */
107 int flash_area_check_int_sha256(const struct flash_area *fa,
108 				const struct flash_area_check *fac);
109 #endif
110 
111 /**
112  * @brief Retrieve partitions flash area from the flash_map.
113  *
114  * Function Retrieves flash_area from flash_map for given partition.
115  *
116  * @param[in]  id ID of the flash partition.
117  * @param[out] fa Pointer which has to reference flash_area. If
118  * @p ID is unknown, it will be NULL on output.
119  *
120  * @return  0 on success, -EACCES if the flash_map is not available ,
121  * -ENOENT if @p ID is unknown, -ENODEV if there is no driver attached
122  * to the area.
123  */
124 int flash_area_open(uint8_t id, const struct flash_area **fa);
125 
126 /**
127  * @brief Close flash_area
128  *
129  * Reserved for future usage and external projects compatibility reason.
130  * Currently is NOP.
131  *
132  * @param[in] fa Flash area to be closed.
133  */
134 void flash_area_close(const struct flash_area *fa);
135 
136 /**
137  * @brief Verify that a device assigned to flash area is ready for use.
138  *
139  * Indicates whether the provided flash area has a device known to be
140  * in a state where it can be used with Flash Map API.
141  *
142  * This can be used with struct flash_area pointers captured from FIXED_PARTITION().
143  * At minimum this means that the device has been successfully initialized.
144  *
145  * @param fa pointer to flash_area object to check.
146  *
147  * @retval true If the device is ready for use.
148  * @retval false If the device is not ready for use or if a NULL pointer is
149  * passed as flash area pointer or device pointer within flash area object
150  * is NULL.
151  */
flash_area_device_is_ready(const struct flash_area * fa)152 static ALWAYS_INLINE bool flash_area_device_is_ready(const struct flash_area *fa)
153 {
154 	return (fa != NULL && device_is_ready(fa->fa_dev));
155 }
156 
157 /**
158  * @brief Read flash area data
159  *
160  * Read data from flash area. Area readout boundaries are asserted before read
161  * request. API has the same limitation regard read-block alignment and size
162  * as wrapped flash driver.
163  *
164  * @param[in]  fa  Flash area
165  * @param[in]  off Offset relative from beginning of flash area to read
166  * @param[out] dst Buffer to store read data
167  * @param[in]  len Number of bytes to read
168  *
169  * @return  0 on success, negative errno code on fail.
170  */
171 int flash_area_read(const struct flash_area *fa, off_t off, void *dst,
172 		    size_t len);
173 
174 /**
175  * @brief Write data to flash area
176  *
177  * Write data to flash area. Area write boundaries are asserted before write
178  * request. API has the same limitation regard write-block alignment and size
179  * as wrapped flash driver.
180  *
181  * @param[in]  fa  Flash area
182  * @param[in]  off Offset relative from beginning of flash area to write
183  * @param[in]  src Buffer with data to be written
184  * @param[in]  len Number of bytes to write
185  *
186  * @return  0 on success, negative errno code on fail.
187  */
188 int flash_area_write(const struct flash_area *fa, off_t off, const void *src,
189 		     size_t len);
190 
191 /**
192  * @brief Erase flash area
193  *
194  * Erase given flash area range. Area boundaries are asserted before erase
195  * request. API has the same limitation regard erase-block alignment and size
196  * as wrapped flash driver.
197  *
198  * @param[in] fa  Flash area
199  * @param[in] off Offset relative from beginning of flash area.
200  * @param[in] len Number of bytes to be erase
201  *
202  * @return  0 on success, negative errno code on fail.
203  */
204 int flash_area_erase(const struct flash_area *fa, off_t off, size_t len);
205 
206 /**
207  * @brief Erase flash area or fill with erase-value
208  *
209  * On program-erase devices this function behaves exactly like flash_area_erase.
210  * On RAM non-volatile device it will call erase, if driver provides such
211  * callback, or will fill given range with erase-value defined by driver.
212  * This function should be only used by code that has not been written
213  * to directly support devices that do not require erase and rely on
214  * device being erased prior to some operations.
215  * Note that emulated erase, on devices that do not require, is done
216  * via write, which affects endurance of device.
217  *
218  * @see flash_area_erase()
219  * @see flash_flatten()
220  *
221  * @param[in] fa  Flash area
222  * @param[in] off Offset relative from beginning of flash area.
223  * @param[in] len Number of bytes to be erase
224  *
225  * @return  0 on success, negative errno code on fail.
226  */
227 int flash_area_flatten(const struct flash_area *fa, off_t off, size_t len);
228 
229 /**
230  * @brief Get write block size of the flash area
231  *
232  * Currently write block size might be treated as read block size, although
233  * most of drivers supports unaligned readout.
234  *
235  * @param[in] fa Flash area
236  *
237  * @return Alignment restriction for flash writes in [B].
238  */
239 uint32_t flash_area_align(const struct flash_area *fa);
240 
241 /**
242  * Retrieve info about sectors within the area.
243  *
244  * @param[in]  fa_id    Given flash area ID
245  * @param[in,out] count On input Capacity of @p sectors, on output number of
246  * sectors Retrieved.
247  * @param[out] sectors  buffer for sectors data
248  *
249  * @return  0 on success, negative errno code on fail. Especially returns
250  * -ENOMEM if There are too many flash pages on the flash_area to fit in the
251  * array.
252  */
253 int flash_area_get_sectors(int fa_id, uint32_t *count,
254 			   struct flash_sector *sectors);
255 
256 /**
257  * Retrieve info about sectors within the area.
258  *
259  * @param[in]  fa       pointer to flash area object.
260  * @param[in,out] count On input Capacity of @p sectors, on output number of
261  * sectors retrieved.
262  * @param[out] sectors  buffer for sectors data
263  *
264  * @return  0 on success, negative errno code on fail. Especially returns
265  * -ENOMEM if There are too many flash pages on the flash_area to fit in the
266  * array.
267  */
268 int flash_area_sectors(const struct flash_area *fa, uint32_t *count, struct flash_sector *sectors);
269 
270 /**
271  * Flash map iteration callback
272  *
273  * @param fa flash area
274  * @param user_data User supplied data
275  *
276  */
277 typedef void (*flash_area_cb_t)(const struct flash_area *fa,
278 				void *user_data);
279 
280 /**
281  * Iterate over flash map
282  *
283  * @param user_cb User callback
284  * @param user_data User supplied data
285  */
286 void flash_area_foreach(flash_area_cb_t user_cb, void *user_data);
287 
288 /**
289  * Check whether given flash area has supporting flash driver
290  * in the system.
291  *
292  * @param[in] fa Flash area.
293  *
294  * @return 1 On success. -ENODEV if no driver match.
295  */
296 int flash_area_has_driver(const struct flash_area *fa);
297 
298 /**
299  * Get driver for given flash area.
300  *
301  * @param[in] fa Flash area.
302  *
303  * @return device driver.
304  */
305 const struct device *flash_area_get_device(const struct flash_area *fa);
306 
307 #if CONFIG_FLASH_MAP_LABELS
308 /**
309  * Get the label property from the device tree
310  *
311  * @param[in] fa Flash area.
312  *
313  * @return The label property if it is defined, otherwise NULL
314  */
315 const char *flash_area_label(const struct flash_area *fa);
316 #endif
317 
318 /**
319  * Get the value expected to be read when accessing any erased
320  * flash byte.
321  * This API is compatible with the MCUBoot's porting layer.
322  *
323  * @param fa Flash area.
324  *
325  * @return Byte value of erase memory.
326  */
327 uint8_t flash_area_erased_val(const struct flash_area *fa);
328 
329 /**
330  * Returns non-0 value if fixed-partition of given DTS node label exists.
331  *
332  * @param label DTS node label
333  *
334  * @return non-0 if fixed-partition node exists and is enabled;
335  *	   0 if node does not exist, is not enabled or is not fixed-partition.
336  */
337 #define FIXED_PARTITION_EXISTS(label) DT_FIXED_PARTITION_EXISTS(DT_NODELABEL(label))
338 
339 /**
340  * Get flash area ID from fixed-partition DTS node label
341  *
342  * @param label DTS node label of a partition
343  *
344  * @return flash area ID
345  */
346 #define FIXED_PARTITION_ID(label) DT_FIXED_PARTITION_ID(DT_NODELABEL(label))
347 
348 /**
349  * Get fixed-partition offset from DTS node label
350  *
351  * @param label DTS node label of a partition
352  *
353  * @return fixed-partition offset, as defined for the partition in DTS.
354  */
355 #define FIXED_PARTITION_OFFSET(label) DT_REG_ADDR(DT_NODELABEL(label))
356 
357 /**
358  * Get fixed-partition offset from DTS node
359  *
360  * @param node DTS node of a partition
361  *
362  * @return fixed-partition offset, as defined for the partition in DTS.
363  */
364 #define FIXED_PARTITION_NODE_OFFSET(node) DT_REG_ADDR(node)
365 
366 /**
367  * Get fixed-partition size for DTS node label
368  *
369  * @param label DTS node label
370  *
371  * @return fixed-partition offset, as defined for the partition in DTS.
372  */
373 #define FIXED_PARTITION_SIZE(label) DT_REG_SIZE(DT_NODELABEL(label))
374 
375 /**
376  * Get fixed-partition size for DTS node
377  *
378  * @param node DTS node of a partition
379  *
380  * @return fixed-partition size, as defined for the partition in DTS.
381  */
382 #define FIXED_PARTITION_NODE_SIZE(node) DT_REG_SIZE(node)
383 
384 /**
385  * Get device pointer for device the area/partition resides on
386  *
387  * @param label DTS node label of a partition
388  *
389  * @return const struct device type pointer
390  */
391 #define FLASH_AREA_DEVICE(label) \
392 	DEVICE_DT_GET(DT_MTD_FROM_FIXED_PARTITION(DT_NODE_BY_FIXED_PARTITION_LABEL(label)))
393 
394 /**
395  * Get device pointer for device the area/partition resides on
396  *
397  * @param label DTS node label of a partition
398  *
399  * @return Pointer to a device.
400  */
401 #define FIXED_PARTITION_DEVICE(label) \
402 	DEVICE_DT_GET(DT_MTD_FROM_FIXED_PARTITION(DT_NODELABEL(label)))
403 
404 /**
405  * Get device pointer for device the area/partition resides on
406  *
407  * @param node DTS node of a partition
408  *
409  * @return Pointer to a device.
410  */
411 #define FIXED_PARTITION_NODE_DEVICE(node) \
412 	DEVICE_DT_GET(DT_MTD_FROM_FIXED_PARTITION(node))
413 
414 /**
415  * Get pointer to flash_area object by partition label
416  *
417  * @param label DTS node label of a partition
418  *
419  * @return Pointer to flash_area type object representing partition
420  */
421 #define FIXED_PARTITION(label)	FIXED_PARTITION_1(DT_NODELABEL(label))
422 
423 /**
424  * Get pointer to flash_area object by partition node in DTS
425  *
426  * @param node DTS node of a partition
427  *
428  * @return Pointer to flash_area type object representing partition
429  */
430 #define FIXED_PARTITION_BY_NODE(node)	FIXED_PARTITION_1(node)
431 
432 /** @cond INTERNAL_HIDDEN */
433 #define FIXED_PARTITION_1(node)	FIXED_PARTITION_0(DT_DEP_ORD(node))
434 #define FIXED_PARTITION_0(ord)							\
435 	((const struct flash_area *)&DT_CAT(global_fixed_partition_ORD_, ord))
436 
437 #define DECLARE_PARTITION(node) DECLARE_PARTITION_0(DT_DEP_ORD(node))
438 #define DECLARE_PARTITION_0(ord)						\
439 	extern const struct flash_area DT_CAT(global_fixed_partition_ORD_, ord);
440 #define FOR_EACH_PARTITION_TABLE(table) DT_FOREACH_CHILD(table, DECLARE_PARTITION)
441 
442 /* Generate declarations */
443 DT_FOREACH_STATUS_OKAY(fixed_partitions, FOR_EACH_PARTITION_TABLE)
444 
445 #undef DECLARE_PARTITION
446 #undef DECLARE_PARTITION_0
447 #undef FOR_EACH_PARTITION_TABLE
448 /** @endcond */
449 
450 #ifdef __cplusplus
451 }
452 #endif
453 
454 /**
455  * @}
456  */
457 
458 #endif /* ZEPHYR_INCLUDE_STORAGE_FLASH_MAP_H_ */
459