xref: /openbmc/linux/include/linux/mtd/map.h (revision 95db3b25)
1 /*
2  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org> et al.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  *
18  */
19 
20 /* Overhauled routines for dealing with different mmap regions of flash */
21 
22 #ifndef __LINUX_MTD_MAP_H__
23 #define __LINUX_MTD_MAP_H__
24 
25 #include <linux/types.h>
26 #include <linux/list.h>
27 #include <linux/string.h>
28 #include <linux/bug.h>
29 #include <linux/kernel.h>
30 #include <linux/io.h>
31 
32 #include <asm/unaligned.h>
33 #include <asm/barrier.h>
34 
35 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
36 #define map_bankwidth(map) 1
37 #define map_bankwidth_is_1(map) (map_bankwidth(map) == 1)
38 #define map_bankwidth_is_large(map) (0)
39 #define map_words(map) (1)
40 #define MAX_MAP_BANKWIDTH 1
41 #else
42 #define map_bankwidth_is_1(map) (0)
43 #endif
44 
45 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
46 # ifdef map_bankwidth
47 #  undef map_bankwidth
48 #  define map_bankwidth(map) ((map)->bankwidth)
49 # else
50 #  define map_bankwidth(map) 2
51 #  define map_bankwidth_is_large(map) (0)
52 #  define map_words(map) (1)
53 # endif
54 #define map_bankwidth_is_2(map) (map_bankwidth(map) == 2)
55 #undef MAX_MAP_BANKWIDTH
56 #define MAX_MAP_BANKWIDTH 2
57 #else
58 #define map_bankwidth_is_2(map) (0)
59 #endif
60 
61 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
62 # ifdef map_bankwidth
63 #  undef map_bankwidth
64 #  define map_bankwidth(map) ((map)->bankwidth)
65 # else
66 #  define map_bankwidth(map) 4
67 #  define map_bankwidth_is_large(map) (0)
68 #  define map_words(map) (1)
69 # endif
70 #define map_bankwidth_is_4(map) (map_bankwidth(map) == 4)
71 #undef MAX_MAP_BANKWIDTH
72 #define MAX_MAP_BANKWIDTH 4
73 #else
74 #define map_bankwidth_is_4(map) (0)
75 #endif
76 
77 /* ensure we never evaluate anything shorted than an unsigned long
78  * to zero, and ensure we'll never miss the end of an comparison (bjd) */
79 
80 #define map_calc_words(map) ((map_bankwidth(map) + (sizeof(unsigned long)-1)) / sizeof(unsigned long))
81 
82 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
83 # ifdef map_bankwidth
84 #  undef map_bankwidth
85 #  define map_bankwidth(map) ((map)->bankwidth)
86 #  if BITS_PER_LONG < 64
87 #   undef map_bankwidth_is_large
88 #   define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
89 #   undef map_words
90 #   define map_words(map) map_calc_words(map)
91 #  endif
92 # else
93 #  define map_bankwidth(map) 8
94 #  define map_bankwidth_is_large(map) (BITS_PER_LONG < 64)
95 #  define map_words(map) map_calc_words(map)
96 # endif
97 #define map_bankwidth_is_8(map) (map_bankwidth(map) == 8)
98 #undef MAX_MAP_BANKWIDTH
99 #define MAX_MAP_BANKWIDTH 8
100 #else
101 #define map_bankwidth_is_8(map) (0)
102 #endif
103 
104 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
105 # ifdef map_bankwidth
106 #  undef map_bankwidth
107 #  define map_bankwidth(map) ((map)->bankwidth)
108 #  undef map_bankwidth_is_large
109 #  define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
110 #  undef map_words
111 #  define map_words(map) map_calc_words(map)
112 # else
113 #  define map_bankwidth(map) 16
114 #  define map_bankwidth_is_large(map) (1)
115 #  define map_words(map) map_calc_words(map)
116 # endif
117 #define map_bankwidth_is_16(map) (map_bankwidth(map) == 16)
118 #undef MAX_MAP_BANKWIDTH
119 #define MAX_MAP_BANKWIDTH 16
120 #else
121 #define map_bankwidth_is_16(map) (0)
122 #endif
123 
124 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
125 /* always use indirect access for 256-bit to preserve kernel stack */
126 # undef map_bankwidth
127 # define map_bankwidth(map) ((map)->bankwidth)
128 # undef map_bankwidth_is_large
129 # define map_bankwidth_is_large(map) (map_bankwidth(map) > BITS_PER_LONG/8)
130 # undef map_words
131 # define map_words(map) map_calc_words(map)
132 #define map_bankwidth_is_32(map) (map_bankwidth(map) == 32)
133 #undef MAX_MAP_BANKWIDTH
134 #define MAX_MAP_BANKWIDTH 32
135 #else
136 #define map_bankwidth_is_32(map) (0)
137 #endif
138 
139 #ifndef map_bankwidth
140 #ifdef CONFIG_MTD
141 #warning "No CONFIG_MTD_MAP_BANK_WIDTH_xx selected. No NOR chip support can work"
142 #endif
143 static inline int map_bankwidth(void *map)
144 {
145 	BUG();
146 	return 0;
147 }
148 #define map_bankwidth_is_large(map) (0)
149 #define map_words(map) (0)
150 #define MAX_MAP_BANKWIDTH 1
151 #endif
152 
153 static inline int map_bankwidth_supported(int w)
154 {
155 	switch (w) {
156 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
157 	case 1:
158 #endif
159 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_2
160 	case 2:
161 #endif
162 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_4
163 	case 4:
164 #endif
165 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_8
166 	case 8:
167 #endif
168 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_16
169 	case 16:
170 #endif
171 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_32
172 	case 32:
173 #endif
174 		return 1;
175 
176 	default:
177 		return 0;
178 	}
179 }
180 
181 #define MAX_MAP_LONGS (((MAX_MAP_BANKWIDTH * 8) + BITS_PER_LONG - 1) / BITS_PER_LONG)
182 
183 typedef union {
184 	unsigned long x[MAX_MAP_LONGS];
185 } map_word;
186 
187 /* The map stuff is very simple. You fill in your struct map_info with
188    a handful of routines for accessing the device, making sure they handle
189    paging etc. correctly if your device needs it. Then you pass it off
190    to a chip probe routine -- either JEDEC or CFI probe or both -- via
191    do_map_probe(). If a chip is recognised, the probe code will invoke the
192    appropriate chip driver (if present) and return a struct mtd_info.
193    At which point, you fill in the mtd->module with your own module
194    address, and register it with the MTD core code. Or you could partition
195    it and register the partitions instead, or keep it for your own private
196    use; whatever.
197 
198    The mtd->priv field will point to the struct map_info, and any further
199    private data required by the chip driver is linked from the
200    mtd->priv->fldrv_priv field. This allows the map driver to get at
201    the destructor function map->fldrv_destroy() when it's tired
202    of living.
203 */
204 
205 struct map_info {
206 	const char *name;
207 	unsigned long size;
208 	resource_size_t phys;
209 #define NO_XIP (-1UL)
210 
211 	void __iomem *virt;
212 	void *cached;
213 
214 	int swap; /* this mapping's byte-swapping requirement */
215 	int bankwidth; /* in octets. This isn't necessarily the width
216 		       of actual bus cycles -- it's the repeat interval
217 		      in bytes, before you are talking to the first chip again.
218 		      */
219 
220 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
221 	map_word (*read)(struct map_info *, unsigned long);
222 	void (*copy_from)(struct map_info *, void *, unsigned long, ssize_t);
223 
224 	void (*write)(struct map_info *, const map_word, unsigned long);
225 	void (*copy_to)(struct map_info *, unsigned long, const void *, ssize_t);
226 
227 	/* We can perhaps put in 'point' and 'unpoint' methods, if we really
228 	   want to enable XIP for non-linear mappings. Not yet though. */
229 #endif
230 	/* It's possible for the map driver to use cached memory in its
231 	   copy_from implementation (and _only_ with copy_from).  However,
232 	   when the chip driver knows some flash area has changed contents,
233 	   it will signal it to the map driver through this routine to let
234 	   the map driver invalidate the corresponding cache as needed.
235 	   If there is no cache to care about this can be set to NULL. */
236 	void (*inval_cache)(struct map_info *, unsigned long, ssize_t);
237 
238 	/* This will be called with 1 as parameter when the first map user
239 	 * needs VPP, and called with 0 when the last user exits. The map
240 	 * core maintains a reference counter, and assumes that VPP is a
241 	 * global resource applying to all mapped flash chips on the system.
242 	 */
243 	void (*set_vpp)(struct map_info *, int);
244 
245 	unsigned long pfow_base;
246 	unsigned long map_priv_1;
247 	unsigned long map_priv_2;
248 	struct device_node *device_node;
249 	void *fldrv_priv;
250 	struct mtd_chip_driver *fldrv;
251 };
252 
253 struct mtd_chip_driver {
254 	struct mtd_info *(*probe)(struct map_info *map);
255 	void (*destroy)(struct mtd_info *);
256 	struct module *module;
257 	char *name;
258 	struct list_head list;
259 };
260 
261 void register_mtd_chip_driver(struct mtd_chip_driver *);
262 void unregister_mtd_chip_driver(struct mtd_chip_driver *);
263 
264 struct mtd_info *do_map_probe(const char *name, struct map_info *map);
265 void map_destroy(struct mtd_info *mtd);
266 
267 #define ENABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 1); } while (0)
268 #define DISABLE_VPP(map) do { if (map->set_vpp) map->set_vpp(map, 0); } while (0)
269 
270 #define INVALIDATE_CACHED_RANGE(map, from, size) \
271 	do { if (map->inval_cache) map->inval_cache(map, from, size); } while (0)
272 
273 
274 static inline int map_word_equal(struct map_info *map, map_word val1, map_word val2)
275 {
276 	int i;
277 
278 	for (i = 0; i < map_words(map); i++) {
279 		if (val1.x[i] != val2.x[i])
280 			return 0;
281 	}
282 
283 	return 1;
284 }
285 
286 static inline map_word map_word_and(struct map_info *map, map_word val1, map_word val2)
287 {
288 	map_word r;
289 	int i;
290 
291 	for (i = 0; i < map_words(map); i++)
292 		r.x[i] = val1.x[i] & val2.x[i];
293 
294 	return r;
295 }
296 
297 static inline map_word map_word_clr(struct map_info *map, map_word val1, map_word val2)
298 {
299 	map_word r;
300 	int i;
301 
302 	for (i = 0; i < map_words(map); i++)
303 		r.x[i] = val1.x[i] & ~val2.x[i];
304 
305 	return r;
306 }
307 
308 static inline map_word map_word_or(struct map_info *map, map_word val1, map_word val2)
309 {
310 	map_word r;
311 	int i;
312 
313 	for (i = 0; i < map_words(map); i++)
314 		r.x[i] = val1.x[i] | val2.x[i];
315 
316 	return r;
317 }
318 
319 static inline int map_word_andequal(struct map_info *map, map_word val1, map_word val2, map_word val3)
320 {
321 	int i;
322 
323 	for (i = 0; i < map_words(map); i++) {
324 		if ((val1.x[i] & val2.x[i]) != val3.x[i])
325 			return 0;
326 	}
327 
328 	return 1;
329 }
330 
331 static inline int map_word_bitsset(struct map_info *map, map_word val1, map_word val2)
332 {
333 	int i;
334 
335 	for (i = 0; i < map_words(map); i++) {
336 		if (val1.x[i] & val2.x[i])
337 			return 1;
338 	}
339 
340 	return 0;
341 }
342 
343 static inline map_word map_word_load(struct map_info *map, const void *ptr)
344 {
345 	map_word r;
346 
347 	if (map_bankwidth_is_1(map))
348 		r.x[0] = *(unsigned char *)ptr;
349 	else if (map_bankwidth_is_2(map))
350 		r.x[0] = get_unaligned((uint16_t *)ptr);
351 	else if (map_bankwidth_is_4(map))
352 		r.x[0] = get_unaligned((uint32_t *)ptr);
353 #if BITS_PER_LONG >= 64
354 	else if (map_bankwidth_is_8(map))
355 		r.x[0] = get_unaligned((uint64_t *)ptr);
356 #endif
357 	else if (map_bankwidth_is_large(map))
358 		memcpy(r.x, ptr, map->bankwidth);
359 	else
360 		BUG();
361 
362 	return r;
363 }
364 
365 static inline map_word map_word_load_partial(struct map_info *map, map_word orig, const unsigned char *buf, int start, int len)
366 {
367 	int i;
368 
369 	if (map_bankwidth_is_large(map)) {
370 		char *dest = (char *)&orig;
371 
372 		memcpy(dest+start, buf, len);
373 	} else {
374 		for (i = start; i < start+len; i++) {
375 			int bitpos;
376 
377 #ifdef __LITTLE_ENDIAN
378 			bitpos = i * 8;
379 #else /* __BIG_ENDIAN */
380 			bitpos = (map_bankwidth(map) - 1 - i) * 8;
381 #endif
382 			orig.x[0] &= ~(0xff << bitpos);
383 			orig.x[0] |= (unsigned long)buf[i-start] << bitpos;
384 		}
385 	}
386 	return orig;
387 }
388 
389 #if BITS_PER_LONG < 64
390 #define MAP_FF_LIMIT 4
391 #else
392 #define MAP_FF_LIMIT 8
393 #endif
394 
395 static inline map_word map_word_ff(struct map_info *map)
396 {
397 	map_word r;
398 	int i;
399 
400 	if (map_bankwidth(map) < MAP_FF_LIMIT) {
401 		int bw = 8 * map_bankwidth(map);
402 
403 		r.x[0] = (1UL << bw) - 1;
404 	} else {
405 		for (i = 0; i < map_words(map); i++)
406 			r.x[i] = ~0UL;
407 	}
408 	return r;
409 }
410 
411 static inline map_word inline_map_read(struct map_info *map, unsigned long ofs)
412 {
413 	map_word r;
414 
415 	if (map_bankwidth_is_1(map))
416 		r.x[0] = __raw_readb(map->virt + ofs);
417 	else if (map_bankwidth_is_2(map))
418 		r.x[0] = __raw_readw(map->virt + ofs);
419 	else if (map_bankwidth_is_4(map))
420 		r.x[0] = __raw_readl(map->virt + ofs);
421 #if BITS_PER_LONG >= 64
422 	else if (map_bankwidth_is_8(map))
423 		r.x[0] = __raw_readq(map->virt + ofs);
424 #endif
425 	else if (map_bankwidth_is_large(map))
426 		memcpy_fromio(r.x, map->virt + ofs, map->bankwidth);
427 	else
428 		BUG();
429 
430 	return r;
431 }
432 
433 static inline void inline_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
434 {
435 	if (map_bankwidth_is_1(map))
436 		__raw_writeb(datum.x[0], map->virt + ofs);
437 	else if (map_bankwidth_is_2(map))
438 		__raw_writew(datum.x[0], map->virt + ofs);
439 	else if (map_bankwidth_is_4(map))
440 		__raw_writel(datum.x[0], map->virt + ofs);
441 #if BITS_PER_LONG >= 64
442 	else if (map_bankwidth_is_8(map))
443 		__raw_writeq(datum.x[0], map->virt + ofs);
444 #endif
445 	else if (map_bankwidth_is_large(map))
446 		memcpy_toio(map->virt+ofs, datum.x, map->bankwidth);
447 	else
448 		BUG();
449 	mb();
450 }
451 
452 static inline void inline_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
453 {
454 	if (map->cached)
455 		memcpy(to, (char *)map->cached + from, len);
456 	else
457 		memcpy_fromio(to, map->virt + from, len);
458 }
459 
460 static inline void inline_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
461 {
462 	memcpy_toio(map->virt + to, from, len);
463 }
464 
465 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
466 #define map_read(map, ofs) (map)->read(map, ofs)
467 #define map_copy_from(map, to, from, len) (map)->copy_from(map, to, from, len)
468 #define map_write(map, datum, ofs) (map)->write(map, datum, ofs)
469 #define map_copy_to(map, to, from, len) (map)->copy_to(map, to, from, len)
470 
471 extern void simple_map_init(struct map_info *);
472 #define map_is_linear(map) (map->phys != NO_XIP)
473 
474 #else
475 #define map_read(map, ofs) inline_map_read(map, ofs)
476 #define map_copy_from(map, to, from, len) inline_map_copy_from(map, to, from, len)
477 #define map_write(map, datum, ofs) inline_map_write(map, datum, ofs)
478 #define map_copy_to(map, to, from, len) inline_map_copy_to(map, to, from, len)
479 
480 
481 #define simple_map_init(map) BUG_ON(!map_bankwidth_supported((map)->bankwidth))
482 #define map_is_linear(map) ({ (void)(map); 1; })
483 
484 #endif /* !CONFIG_MTD_COMPLEX_MAPPINGS */
485 
486 #endif /* __LINUX_MTD_MAP_H__ */
487