map.h

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