xref: /linux/include/linux/mtd/map.h (revision 8d2b0853add1d7534dc0794e3c8e0b9e8c4ec640)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org> et al.
4  */
5 
6 /* Overhauled routines for dealing with different mmap regions of flash */
7 
8 #ifndef __LINUX_MTD_MAP_H__
9 #define __LINUX_MTD_MAP_H__
10 
11 #include <linux/bug.h>
12 #include <linux/io.h>
13 #include <linux/ioport.h>
14 #include <linux/string.h>
15 #include <linux/types.h>
16 #include <linux/unaligned.h>
17 
18 struct device_node;
19 struct module;
20 
21 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
22 #define map_bankwidth(map) 1
23 #define map_bankwidth_is_1(map) (map_bankwidth(map) == 1)
24 #define map_bankwidth_is_large(map) (0)
25 #define map_words(map) (1)
26 #define MAX_MAP_BANKWIDTH 1
27 #else
28 #define map_bankwidth_is_1(map) (0)
29 #endif
30 
31 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
32 # ifdef map_bankwidth
33 #  undef map_bankwidth
34 #  define map_bankwidth(map) ((map)->bankwidth)
35 # else
36 #  define map_bankwidth(map) 2
37 #  define map_bankwidth_is_large(map) (0)
38 #  define map_words(map) (1)
39 # endif
40 #define map_bankwidth_is_2(map) (map_bankwidth(map) == 2)
41 #undef MAX_MAP_BANKWIDTH
42 #define MAX_MAP_BANKWIDTH 2
43 #else
44 #define map_bankwidth_is_2(map) (0)
45 #endif
46 
47 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
48 # ifdef map_bankwidth
49 #  undef map_bankwidth
50 #  define map_bankwidth(map) ((map)->bankwidth)
51 # else
52 #  define map_bankwidth(map) 4
53 #  define map_bankwidth_is_large(map) (0)
54 #  define map_words(map) (1)
55 # endif
56 #define map_bankwidth_is_4(map) (map_bankwidth(map) == 4)
57 #undef MAX_MAP_BANKWIDTH
58 #define MAX_MAP_BANKWIDTH 4
59 #else
60 #define map_bankwidth_is_4(map) (0)
61 #endif
62 
63 /* ensure we never evaluate anything shorted than an unsigned long
64  * to zero, and ensure we'll never miss the end of an comparison (bjd) */
65 
66 #define map_calc_words(map) ((map_bankwidth(map) + (sizeof(unsigned long)-1)) / sizeof(unsigned long))
67 
68 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
69 # ifdef map_bankwidth
70 #  undef map_bankwidth
71 #  define map_bankwidth(map) ((map)->bankwidth)
72 #  if BITS_PER_LONG < 64
73 #   undef map_bankwidth_is_large
74 #   define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
75 #   undef map_words
76 #   define map_words(map) map_calc_words(map)
77 #  endif
78 # else
79 #  define map_bankwidth(map) 8
80 #  define map_bankwidth_is_large(map) (BITS_PER_LONG < 64)
81 #  define map_words(map) map_calc_words(map)
82 # endif
83 #define map_bankwidth_is_8(map) (map_bankwidth(map) == 8)
84 #undef MAX_MAP_BANKWIDTH
85 #define MAX_MAP_BANKWIDTH 8
86 #else
87 #define map_bankwidth_is_8(map) (0)
88 #endif
89 
90 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
91 # ifdef map_bankwidth
92 #  undef map_bankwidth
93 #  define map_bankwidth(map) ((map)->bankwidth)
94 #  undef map_bankwidth_is_large
95 #  define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
96 #  undef map_words
97 #  define map_words(map) map_calc_words(map)
98 # else
99 #  define map_bankwidth(map) 16
100 #  define map_bankwidth_is_large(map) (1)
101 #  define map_words(map) map_calc_words(map)
102 # endif
103 #define map_bankwidth_is_16(map) (map_bankwidth(map) == 16)
104 #undef MAX_MAP_BANKWIDTH
105 #define MAX_MAP_BANKWIDTH 16
106 #else
107 #define map_bankwidth_is_16(map) (0)
108 #endif
109 
110 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
111 /* always use indirect access for 256-bit to preserve kernel stack */
112 # undef map_bankwidth
113 # define map_bankwidth(map) ((map)->bankwidth)
114 # undef map_bankwidth_is_large
115 # define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
116 # undef map_words
117 # define map_words(map) map_calc_words(map)
118 #define map_bankwidth_is_32(map) (map_bankwidth(map) == 32)
119 #undef MAX_MAP_BANKWIDTH
120 #define MAX_MAP_BANKWIDTH 32
121 #else
122 #define map_bankwidth_is_32(map) (0)
123 #endif
124 
125 #ifndef map_bankwidth
126 #ifdef CONFIG_MTD
127 #warning "No CONFIG_MTD_MAP_BANK_WIDTH_xx selected. No NOR chip support can work"
128 #endif
129 static inline int map_bankwidth(void *map)
130 {
131 	BUG();
132 	return 0;
133 }
134 #define map_bankwidth_is_large(map) (0)
135 #define map_words(map) (0)
136 #define MAX_MAP_BANKWIDTH 1
137 #endif
138 
139 static inline int map_bankwidth_supported(int w)
140 {
141 	switch (w) {
142 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
143 	case 1:
144 #endif
145 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
146 	case 2:
147 #endif
148 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
149 	case 4:
150 #endif
151 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
152 	case 8:
153 #endif
154 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
155 	case 16:
156 #endif
157 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
158 	case 32:
159 #endif
160 		return 1;
161 
162 	default:
163 		return 0;
164 	}
165 }
166 
167 #define MAX_MAP_LONGS (((MAX_MAP_BANKWIDTH * 8) + BITS_PER_LONG - 1) / BITS_PER_LONG)
168 
169 typedef union {
170 	unsigned long x[MAX_MAP_LONGS];
171 } map_word;
172 
173 /* The map stuff is very simple. You fill in your struct map_info with
174    a handful of routines for accessing the device, making sure they handle
175    paging etc. correctly if your device needs it. Then you pass it off
176    to a chip probe routine -- either JEDEC or CFI probe or both -- via
177    do_map_probe(). If a chip is recognised, the probe code will invoke the
178    appropriate chip driver (if present) and return a struct mtd_info.
179    At which point, you fill in the mtd->module with your own module
180    address, and register it with the MTD core code. Or you could partition
181    it and register the partitions instead, or keep it for your own private
182    use; whatever.
183 
184    The mtd->priv field will point to the struct map_info, and any further
185    private data required by the chip driver is linked from the
186    mtd->priv->fldrv_priv field. This allows the map driver to get at
187    the destructor function map->fldrv_destroy() when it's tired
188    of living.
189 */
190 
191 struct mtd_chip_driver;
192 struct map_info {
193 	const char *name;
194 	unsigned long size;
195 	resource_size_t phys;
196 #define NO_XIP (-1UL)
197 
198 	void __iomem *virt;
199 	void *cached;
200 
201 	int swap; /* this mapping's byte-swapping requirement */
202 	int bankwidth; /* in octets. This isn't necessarily the width
203 		       of actual bus cycles -- it's the repeat interval
204 		      in bytes, before you are talking to the first chip again.
205 		      */
206 
207 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
208 	map_word (*read)(struct map_info *, unsigned long);
209 	void (*copy_from)(struct map_info *, void *, unsigned long, ssize_t);
210 
211 	void (*write)(struct map_info *, const map_word, unsigned long);
212 	void (*copy_to)(struct map_info *, unsigned long, const void *, ssize_t);
213 
214 	/* We can perhaps put in 'point' and 'unpoint' methods, if we really
215 	   want to enable XIP for non-linear mappings. Not yet though. */
216 #endif
217 	/* It's possible for the map driver to use cached memory in its
218 	   copy_from implementation (and _only_ with copy_from).  However,
219 	   when the chip driver knows some flash area has changed contents,
220 	   it will signal it to the map driver through this routine to let
221 	   the map driver invalidate the corresponding cache as needed.
222 	   If there is no cache to care about this can be set to NULL. */
223 	void (*inval_cache)(struct map_info *, unsigned long, ssize_t);
224 
225 	/* This will be called with 1 as parameter when the first map user
226 	 * needs VPP, and called with 0 when the last user exits. The map
227 	 * core maintains a reference counter, and assumes that VPP is a
228 	 * global resource applying to all mapped flash chips on the system.
229 	 */
230 	void (*set_vpp)(struct map_info *, int);
231 
232 	unsigned long pfow_base;
233 	unsigned long map_priv_1;
234 	unsigned long map_priv_2;
235 	struct device_node *device_node;
236 	void *fldrv_priv;
237 	struct mtd_chip_driver *fldrv;
238 };
239 
240 struct mtd_chip_driver {
241 	struct mtd_info *(*probe)(struct map_info *map);
242 	void (*destroy)(struct mtd_info *);
243 	struct module *module;
244 	char *name;
245 	struct list_head list;
246 };
247 
248 void register_mtd_chip_driver(struct mtd_chip_driver *);
249 void unregister_mtd_chip_driver(struct mtd_chip_driver *);
250 
251 struct mtd_info *do_map_probe(const char *name, struct map_info *map);
252 void map_destroy(struct mtd_info *mtd);
253 
254 #define ENABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 1); } while (0)
255 #define DISABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 0); } while (0)
256 
257 #define INVALIDATE_CACHED_RANGE(map, from, size) \
258 	do { if (map->inval_cache) map->inval_cache(map, from, size); } while (0)
259 
260 #define map_word_equal(map, val1, val2)					\
261 ({									\
262 	int i, ret = 1;							\
263 	for (i = 0; i < map_words(map); i++)				\
264 		if ((val1).x[i] != (val2).x[i]) {			\
265 			ret = 0;					\
266 			break;						\
267 		}							\
268 	ret;								\
269 })
270 
271 #define map_word_and(map, val1, val2)					\
272 ({									\
273 	map_word r;							\
274 	int i;								\
275 	for (i = 0; i < map_words(map); i++)				\
276 		r.x[i] = (val1).x[i] & (val2).x[i];			\
277 	r;								\
278 })
279 
280 #define map_word_clr(map, val1, val2)					\
281 ({									\
282 	map_word r;							\
283 	int i;								\
284 	for (i = 0; i < map_words(map); i++)				\
285 		r.x[i] = (val1).x[i] & ~(val2).x[i];			\
286 	r;								\
287 })
288 
289 #define map_word_or(map, val1, val2)					\
290 ({									\
291 	map_word r;							\
292 	int i;								\
293 	for (i = 0; i < map_words(map); i++)				\
294 		r.x[i] = (val1).x[i] | (val2).x[i];			\
295 	r;								\
296 })
297 
298 #define map_word_andequal(map, val1, val2, val3)			\
299 ({									\
300 	int i, ret = 1;							\
301 	for (i = 0; i < map_words(map); i++) {				\
302 		if (((val1).x[i] & (val2).x[i]) != (val3).x[i]) {	\
303 			ret = 0;					\
304 			break;						\
305 		}							\
306 	}								\
307 	ret;								\
308 })
309 
310 #define map_word_bitsset(map, val1, val2)				\
311 ({									\
312 	int i, ret = 0;							\
313 	for (i = 0; i < map_words(map); i++) {				\
314 		if ((val1).x[i] & (val2).x[i]) {			\
315 			ret = 1;					\
316 			break;						\
317 		}							\
318 	}								\
319 	ret;								\
320 })
321 
322 static inline map_word map_word_load(struct map_info *map, const void *ptr)
323 {
324 	map_word r;
325 
326 	if (map_bankwidth_is_1(map))
327 		r.x[0] = *(unsigned char *)ptr;
328 	else if (map_bankwidth_is_2(map))
329 		r.x[0] = get_unaligned((uint16_t *)ptr);
330 	else if (map_bankwidth_is_4(map))
331 		r.x[0] = get_unaligned((uint32_t *)ptr);
332 #if BITS_PER_LONG >= 64
333 	else if (map_bankwidth_is_8(map))
334 		r.x[0] = get_unaligned((uint64_t *)ptr);
335 #endif
336 	else if (map_bankwidth_is_large(map))
337 		memcpy(r.x, ptr, map->bankwidth);
338 	else
339 		BUG();
340 
341 	return r;
342 }
343 
344 static inline map_word map_word_load_partial(struct map_info *map, map_word orig, const unsigned char *buf, int start, int len)
345 {
346 	int i;
347 
348 	if (map_bankwidth_is_large(map)) {
349 		char *dest = (char *)&orig;
350 
351 		memcpy(dest+start, buf, len);
352 	} else {
353 		for (i = start; i < start+len; i++) {
354 			int bitpos;
355 
356 #ifdef __LITTLE_ENDIAN
357 			bitpos = i * 8;
358 #else /* __BIG_ENDIAN */
359 			bitpos = (map_bankwidth(map) - 1 - i) * 8;
360 #endif
361 			orig.x[0] &= ~(0xff << bitpos);
362 			orig.x[0] |= (unsigned long)buf[i-start] << bitpos;
363 		}
364 	}
365 	return orig;
366 }
367 
368 #if BITS_PER_LONG < 64
369 #define MAP_FF_LIMIT 4
370 #else
371 #define MAP_FF_LIMIT 8
372 #endif
373 
374 static inline map_word map_word_ff(struct map_info *map)
375 {
376 	map_word r;
377 	int i;
378 
379 	if (map_bankwidth(map) < MAP_FF_LIMIT) {
380 		int bw = 8 * map_bankwidth(map);
381 
382 		r.x[0] = (1UL << bw) - 1;
383 	} else {
384 		for (i = 0; i < map_words(map); i++)
385 			r.x[i] = ~0UL;
386 	}
387 	return r;
388 }
389 
390 static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
391 {
392 	map_word r;
393 
394 	if (map_bankwidth_is_1(map))
395 		r.x[0] = __raw_readb(map->virt + ofs);
396 	else if (map_bankwidth_is_2(map))
397 		r.x[0] = __raw_readw(map->virt + ofs);
398 	else if (map_bankwidth_is_4(map))
399 		r.x[0] = __raw_readl(map->virt + ofs);
400 #if BITS_PER_LONG >= 64
401 	else if (map_bankwidth_is_8(map))
402 		r.x[0] = __raw_readq(map->virt + ofs);
403 #endif
404 	else if (map_bankwidth_is_large(map))
405 		memcpy_fromio(r.x, map->virt + ofs, map->bankwidth);
406 	else
407 		BUG();
408 
409 	return r;
410 }
411 
412 static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
413 {
414 	if (map_bankwidth_is_1(map))
415 		__raw_writeb(datum.x[0], map->virt + ofs);
416 	else if (map_bankwidth_is_2(map))
417 		__raw_writew(datum.x[0], map->virt + ofs);
418 	else if (map_bankwidth_is_4(map))
419 		__raw_writel(datum.x[0], map->virt + ofs);
420 #if BITS_PER_LONG >= 64
421 	else if (map_bankwidth_is_8(map))
422 		__raw_writeq(datum.x[0], map->virt + ofs);
423 #endif
424 	else if (map_bankwidth_is_large(map))
425 		memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
426 	else
427 		BUG();
428 	mb();
429 }
430 
431 static inline void inline_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
432 {
433 	if (map->cached)
434 		memcpy(to, (char *)map->cached + from, len);
435 	else
436 		memcpy_fromio(to, map->virt + from, len);
437 }
438 
439 static inline void inline_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
440 {
441 	memcpy_toio(map->virt + to, from, len);
442 }
443 
444 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
445 #define map_read(map, ofs) (map)->read(map, ofs)
446 #define map_copy_from(map, to, from, len) (map)->copy_from(map, to, from, len)
447 #define map_write(map, datum, ofs) (map)->write(map, datum, ofs)
448 #define map_copy_to(map, to, from, len) (map)->copy_to(map, to, from, len)
449 
450 extern void simple_map_init(struct map_info *);
451 #define map_is_linear(map) (map->phys != NO_XIP)
452 
453 #else
454 #define map_read(map, ofs) inline_map_read(map, ofs)
455 #define map_copy_from(map, to, from, len) inline_map_copy_from(map, to, from, len)
456 #define map_write(map, datum, ofs) inline_map_write(map, datum, ofs)
457 #define map_copy_to(map, to, from, len) inline_map_copy_to(map, to, from, len)
458 
459 
460 #define simple_map_init(map) BUG_ON(!map_bankwidth_supported((map)->bankwidth))
461 #define map_is_linear(map) ({ (void)(map); 1; })
462 
463 #endif /* !CONFIG_MTD_COMPLEX_MAPPINGS */
464 
465 #endif /* __LINUX_MTD_MAP_H__ */
466