xref: /openbmc/linux/drivers/mtd/spi-nor/sfdp.c (revision 0661cb2a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2005, Intec Automation Inc.
4  * Copyright (C) 2014, Freescale Semiconductor, Inc.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/slab.h>
9 #include <linux/sort.h>
10 #include <linux/mtd/spi-nor.h>
11 
12 #include "core.h"
13 
14 #define SFDP_PARAM_HEADER_ID(p)	(((p)->id_msb << 8) | (p)->id_lsb)
15 #define SFDP_PARAM_HEADER_PTP(p) \
16 	(((p)->parameter_table_pointer[2] << 16) | \
17 	 ((p)->parameter_table_pointer[1] <<  8) | \
18 	 ((p)->parameter_table_pointer[0] <<  0))
19 #define SFDP_PARAM_HEADER_PARAM_LEN(p) ((p)->length * 4)
20 
21 #define SFDP_BFPT_ID		0xff00	/* Basic Flash Parameter Table */
22 #define SFDP_SECTOR_MAP_ID	0xff81	/* Sector Map Table */
23 #define SFDP_4BAIT_ID		0xff84  /* 4-byte Address Instruction Table */
24 #define SFDP_PROFILE1_ID	0xff05	/* xSPI Profile 1.0 table. */
25 #define SFDP_SCCR_MAP_ID	0xff87	/*
26 					 * Status, Control and Configuration
27 					 * Register Map.
28 					 */
29 
30 #define SFDP_SIGNATURE		0x50444653U
31 
32 struct sfdp_header {
33 	u32		signature; /* Ox50444653U <=> "SFDP" */
34 	u8		minor;
35 	u8		major;
36 	u8		nph; /* 0-base number of parameter headers */
37 	u8		unused;
38 
39 	/* Basic Flash Parameter Table. */
40 	struct sfdp_parameter_header	bfpt_header;
41 };
42 
43 /* Fast Read settings. */
44 struct sfdp_bfpt_read {
45 	/* The Fast Read x-y-z hardware capability in params->hwcaps.mask. */
46 	u32			hwcaps;
47 
48 	/*
49 	 * The <supported_bit> bit in <supported_dword> BFPT DWORD tells us
50 	 * whether the Fast Read x-y-z command is supported.
51 	 */
52 	u32			supported_dword;
53 	u32			supported_bit;
54 
55 	/*
56 	 * The half-word at offset <setting_shift> in <setting_dword> BFPT DWORD
57 	 * encodes the op code, the number of mode clocks and the number of wait
58 	 * states to be used by Fast Read x-y-z command.
59 	 */
60 	u32			settings_dword;
61 	u32			settings_shift;
62 
63 	/* The SPI protocol for this Fast Read x-y-z command. */
64 	enum spi_nor_protocol	proto;
65 };
66 
67 struct sfdp_bfpt_erase {
68 	/*
69 	 * The half-word at offset <shift> in DWORD <dword> encodes the
70 	 * op code and erase sector size to be used by Sector Erase commands.
71 	 */
72 	u32			dword;
73 	u32			shift;
74 };
75 
76 #define SMPT_CMD_ADDRESS_LEN_MASK		GENMASK(23, 22)
77 #define SMPT_CMD_ADDRESS_LEN_0			(0x0UL << 22)
78 #define SMPT_CMD_ADDRESS_LEN_3			(0x1UL << 22)
79 #define SMPT_CMD_ADDRESS_LEN_4			(0x2UL << 22)
80 #define SMPT_CMD_ADDRESS_LEN_USE_CURRENT	(0x3UL << 22)
81 
82 #define SMPT_CMD_READ_DUMMY_MASK		GENMASK(19, 16)
83 #define SMPT_CMD_READ_DUMMY_SHIFT		16
84 #define SMPT_CMD_READ_DUMMY(_cmd) \
85 	(((_cmd) & SMPT_CMD_READ_DUMMY_MASK) >> SMPT_CMD_READ_DUMMY_SHIFT)
86 #define SMPT_CMD_READ_DUMMY_IS_VARIABLE		0xfUL
87 
88 #define SMPT_CMD_READ_DATA_MASK			GENMASK(31, 24)
89 #define SMPT_CMD_READ_DATA_SHIFT		24
90 #define SMPT_CMD_READ_DATA(_cmd) \
91 	(((_cmd) & SMPT_CMD_READ_DATA_MASK) >> SMPT_CMD_READ_DATA_SHIFT)
92 
93 #define SMPT_CMD_OPCODE_MASK			GENMASK(15, 8)
94 #define SMPT_CMD_OPCODE_SHIFT			8
95 #define SMPT_CMD_OPCODE(_cmd) \
96 	(((_cmd) & SMPT_CMD_OPCODE_MASK) >> SMPT_CMD_OPCODE_SHIFT)
97 
98 #define SMPT_MAP_REGION_COUNT_MASK		GENMASK(23, 16)
99 #define SMPT_MAP_REGION_COUNT_SHIFT		16
100 #define SMPT_MAP_REGION_COUNT(_header) \
101 	((((_header) & SMPT_MAP_REGION_COUNT_MASK) >> \
102 	  SMPT_MAP_REGION_COUNT_SHIFT) + 1)
103 
104 #define SMPT_MAP_ID_MASK			GENMASK(15, 8)
105 #define SMPT_MAP_ID_SHIFT			8
106 #define SMPT_MAP_ID(_header) \
107 	(((_header) & SMPT_MAP_ID_MASK) >> SMPT_MAP_ID_SHIFT)
108 
109 #define SMPT_MAP_REGION_SIZE_MASK		GENMASK(31, 8)
110 #define SMPT_MAP_REGION_SIZE_SHIFT		8
111 #define SMPT_MAP_REGION_SIZE(_region) \
112 	(((((_region) & SMPT_MAP_REGION_SIZE_MASK) >> \
113 	   SMPT_MAP_REGION_SIZE_SHIFT) + 1) * 256)
114 
115 #define SMPT_MAP_REGION_ERASE_TYPE_MASK		GENMASK(3, 0)
116 #define SMPT_MAP_REGION_ERASE_TYPE(_region) \
117 	((_region) & SMPT_MAP_REGION_ERASE_TYPE_MASK)
118 
119 #define SMPT_DESC_TYPE_MAP			BIT(1)
120 #define SMPT_DESC_END				BIT(0)
121 
122 #define SFDP_4BAIT_DWORD_MAX	2
123 
124 struct sfdp_4bait {
125 	/* The hardware capability. */
126 	u32		hwcaps;
127 
128 	/*
129 	 * The <supported_bit> bit in DWORD1 of the 4BAIT tells us whether
130 	 * the associated 4-byte address op code is supported.
131 	 */
132 	u32		supported_bit;
133 };
134 
135 /**
136  * spi_nor_read_raw() - raw read of serial flash memory. read_opcode,
137  *			addr_width and read_dummy members of the struct spi_nor
138  *			should be previously
139  * set.
140  * @nor:	pointer to a 'struct spi_nor'
141  * @addr:	offset in the serial flash memory
142  * @len:	number of bytes to read
143  * @buf:	buffer where the data is copied into (dma-safe memory)
144  *
145  * Return: 0 on success, -errno otherwise.
146  */
147 static int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf)
148 {
149 	ssize_t ret;
150 
151 	while (len) {
152 		ret = spi_nor_read_data(nor, addr, len, buf);
153 		if (ret < 0)
154 			return ret;
155 		if (!ret || ret > len)
156 			return -EIO;
157 
158 		buf += ret;
159 		addr += ret;
160 		len -= ret;
161 	}
162 	return 0;
163 }
164 
165 /**
166  * spi_nor_read_sfdp() - read Serial Flash Discoverable Parameters.
167  * @nor:	pointer to a 'struct spi_nor'
168  * @addr:	offset in the SFDP area to start reading data from
169  * @len:	number of bytes to read
170  * @buf:	buffer where the SFDP data are copied into (dma-safe memory)
171  *
172  * Whatever the actual numbers of bytes for address and dummy cycles are
173  * for (Fast) Read commands, the Read SFDP (5Ah) instruction is always
174  * followed by a 3-byte address and 8 dummy clock cycles.
175  *
176  * Return: 0 on success, -errno otherwise.
177  */
178 static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr,
179 			     size_t len, void *buf)
180 {
181 	u8 addr_width, read_opcode, read_dummy;
182 	int ret;
183 
184 	read_opcode = nor->read_opcode;
185 	addr_width = nor->addr_width;
186 	read_dummy = nor->read_dummy;
187 
188 	nor->read_opcode = SPINOR_OP_RDSFDP;
189 	nor->addr_width = 3;
190 	nor->read_dummy = 8;
191 
192 	ret = spi_nor_read_raw(nor, addr, len, buf);
193 
194 	nor->read_opcode = read_opcode;
195 	nor->addr_width = addr_width;
196 	nor->read_dummy = read_dummy;
197 
198 	return ret;
199 }
200 
201 /**
202  * spi_nor_read_sfdp_dma_unsafe() - read Serial Flash Discoverable Parameters.
203  * @nor:	pointer to a 'struct spi_nor'
204  * @addr:	offset in the SFDP area to start reading data from
205  * @len:	number of bytes to read
206  * @buf:	buffer where the SFDP data are copied into
207  *
208  * Wrap spi_nor_read_sfdp() using a kmalloc'ed bounce buffer as @buf is now not
209  * guaranteed to be dma-safe.
210  *
211  * Return: -ENOMEM if kmalloc() fails, the return code of spi_nor_read_sfdp()
212  *          otherwise.
213  */
214 static int spi_nor_read_sfdp_dma_unsafe(struct spi_nor *nor, u32 addr,
215 					size_t len, void *buf)
216 {
217 	void *dma_safe_buf;
218 	int ret;
219 
220 	dma_safe_buf = kmalloc(len, GFP_KERNEL);
221 	if (!dma_safe_buf)
222 		return -ENOMEM;
223 
224 	ret = spi_nor_read_sfdp(nor, addr, len, dma_safe_buf);
225 	memcpy(buf, dma_safe_buf, len);
226 	kfree(dma_safe_buf);
227 
228 	return ret;
229 }
230 
231 static void
232 spi_nor_set_read_settings_from_bfpt(struct spi_nor_read_command *read,
233 				    u16 half,
234 				    enum spi_nor_protocol proto)
235 {
236 	read->num_mode_clocks = (half >> 5) & 0x07;
237 	read->num_wait_states = (half >> 0) & 0x1f;
238 	read->opcode = (half >> 8) & 0xff;
239 	read->proto = proto;
240 }
241 
242 static const struct sfdp_bfpt_read sfdp_bfpt_reads[] = {
243 	/* Fast Read 1-1-2 */
244 	{
245 		SNOR_HWCAPS_READ_1_1_2,
246 		BFPT_DWORD(1), BIT(16),	/* Supported bit */
247 		BFPT_DWORD(4), 0,	/* Settings */
248 		SNOR_PROTO_1_1_2,
249 	},
250 
251 	/* Fast Read 1-2-2 */
252 	{
253 		SNOR_HWCAPS_READ_1_2_2,
254 		BFPT_DWORD(1), BIT(20),	/* Supported bit */
255 		BFPT_DWORD(4), 16,	/* Settings */
256 		SNOR_PROTO_1_2_2,
257 	},
258 
259 	/* Fast Read 2-2-2 */
260 	{
261 		SNOR_HWCAPS_READ_2_2_2,
262 		BFPT_DWORD(5),  BIT(0),	/* Supported bit */
263 		BFPT_DWORD(6), 16,	/* Settings */
264 		SNOR_PROTO_2_2_2,
265 	},
266 
267 	/* Fast Read 1-1-4 */
268 	{
269 		SNOR_HWCAPS_READ_1_1_4,
270 		BFPT_DWORD(1), BIT(22),	/* Supported bit */
271 		BFPT_DWORD(3), 16,	/* Settings */
272 		SNOR_PROTO_1_1_4,
273 	},
274 
275 	/* Fast Read 1-4-4 */
276 	{
277 		SNOR_HWCAPS_READ_1_4_4,
278 		BFPT_DWORD(1), BIT(21),	/* Supported bit */
279 		BFPT_DWORD(3), 0,	/* Settings */
280 		SNOR_PROTO_1_4_4,
281 	},
282 
283 	/* Fast Read 4-4-4 */
284 	{
285 		SNOR_HWCAPS_READ_4_4_4,
286 		BFPT_DWORD(5), BIT(4),	/* Supported bit */
287 		BFPT_DWORD(7), 16,	/* Settings */
288 		SNOR_PROTO_4_4_4,
289 	},
290 };
291 
292 static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
293 	/* Erase Type 1 in DWORD8 bits[15:0] */
294 	{BFPT_DWORD(8), 0},
295 
296 	/* Erase Type 2 in DWORD8 bits[31:16] */
297 	{BFPT_DWORD(8), 16},
298 
299 	/* Erase Type 3 in DWORD9 bits[15:0] */
300 	{BFPT_DWORD(9), 0},
301 
302 	/* Erase Type 4 in DWORD9 bits[31:16] */
303 	{BFPT_DWORD(9), 16},
304 };
305 
306 /**
307  * spi_nor_set_erase_settings_from_bfpt() - set erase type settings from BFPT
308  * @erase:	pointer to a structure that describes a SPI NOR erase type
309  * @size:	the size of the sector/block erased by the erase type
310  * @opcode:	the SPI command op code to erase the sector/block
311  * @i:		erase type index as sorted in the Basic Flash Parameter Table
312  *
313  * The supported Erase Types will be sorted at init in ascending order, with
314  * the smallest Erase Type size being the first member in the erase_type array
315  * of the spi_nor_erase_map structure. Save the Erase Type index as sorted in
316  * the Basic Flash Parameter Table since it will be used later on to
317  * synchronize with the supported Erase Types defined in SFDP optional tables.
318  */
319 static void
320 spi_nor_set_erase_settings_from_bfpt(struct spi_nor_erase_type *erase,
321 				     u32 size, u8 opcode, u8 i)
322 {
323 	erase->idx = i;
324 	spi_nor_set_erase_type(erase, size, opcode);
325 }
326 
327 /**
328  * spi_nor_map_cmp_erase_type() - compare the map's erase types by size
329  * @l:	member in the left half of the map's erase_type array
330  * @r:	member in the right half of the map's erase_type array
331  *
332  * Comparison function used in the sort() call to sort in ascending order the
333  * map's erase types, the smallest erase type size being the first member in the
334  * sorted erase_type array.
335  *
336  * Return: the result of @l->size - @r->size
337  */
338 static int spi_nor_map_cmp_erase_type(const void *l, const void *r)
339 {
340 	const struct spi_nor_erase_type *left = l, *right = r;
341 
342 	return left->size - right->size;
343 }
344 
345 /**
346  * spi_nor_sort_erase_mask() - sort erase mask
347  * @map:	the erase map of the SPI NOR
348  * @erase_mask:	the erase type mask to be sorted
349  *
350  * Replicate the sort done for the map's erase types in BFPT: sort the erase
351  * mask in ascending order with the smallest erase type size starting from
352  * BIT(0) in the sorted erase mask.
353  *
354  * Return: sorted erase mask.
355  */
356 static u8 spi_nor_sort_erase_mask(struct spi_nor_erase_map *map, u8 erase_mask)
357 {
358 	struct spi_nor_erase_type *erase_type = map->erase_type;
359 	int i;
360 	u8 sorted_erase_mask = 0;
361 
362 	if (!erase_mask)
363 		return 0;
364 
365 	/* Replicate the sort done for the map's erase types. */
366 	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
367 		if (erase_type[i].size && erase_mask & BIT(erase_type[i].idx))
368 			sorted_erase_mask |= BIT(i);
369 
370 	return sorted_erase_mask;
371 }
372 
373 /**
374  * spi_nor_regions_sort_erase_types() - sort erase types in each region
375  * @map:	the erase map of the SPI NOR
376  *
377  * Function assumes that the erase types defined in the erase map are already
378  * sorted in ascending order, with the smallest erase type size being the first
379  * member in the erase_type array. It replicates the sort done for the map's
380  * erase types. Each region's erase bitmask will indicate which erase types are
381  * supported from the sorted erase types defined in the erase map.
382  * Sort the all region's erase type at init in order to speed up the process of
383  * finding the best erase command at runtime.
384  */
385 static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
386 {
387 	struct spi_nor_erase_region *region = map->regions;
388 	u8 region_erase_mask, sorted_erase_mask;
389 
390 	while (region) {
391 		region_erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
392 
393 		sorted_erase_mask = spi_nor_sort_erase_mask(map,
394 							    region_erase_mask);
395 
396 		/* Overwrite erase mask. */
397 		region->offset = (region->offset & ~SNOR_ERASE_TYPE_MASK) |
398 				 sorted_erase_mask;
399 
400 		region = spi_nor_region_next(region);
401 	}
402 }
403 
404 /**
405  * spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
406  * @nor:		pointer to a 'struct spi_nor'
407  * @bfpt_header:	pointer to the 'struct sfdp_parameter_header' describing
408  *			the Basic Flash Parameter Table length and version
409  *
410  * The Basic Flash Parameter Table is the main and only mandatory table as
411  * defined by the SFDP (JESD216) specification.
412  * It provides us with the total size (memory density) of the data array and
413  * the number of address bytes for Fast Read, Page Program and Sector Erase
414  * commands.
415  * For Fast READ commands, it also gives the number of mode clock cycles and
416  * wait states (regrouped in the number of dummy clock cycles) for each
417  * supported instruction op code.
418  * For Page Program, the page size is now available since JESD216 rev A, however
419  * the supported instruction op codes are still not provided.
420  * For Sector Erase commands, this table stores the supported instruction op
421  * codes and the associated sector sizes.
422  * Finally, the Quad Enable Requirements (QER) are also available since JESD216
423  * rev A. The QER bits encode the manufacturer dependent procedure to be
424  * executed to set the Quad Enable (QE) bit in some internal register of the
425  * Quad SPI memory. Indeed the QE bit, when it exists, must be set before
426  * sending any Quad SPI command to the memory. Actually, setting the QE bit
427  * tells the memory to reassign its WP# and HOLD#/RESET# pins to functions IO2
428  * and IO3 hence enabling 4 (Quad) I/O lines.
429  *
430  * Return: 0 on success, -errno otherwise.
431  */
432 static int spi_nor_parse_bfpt(struct spi_nor *nor,
433 			      const struct sfdp_parameter_header *bfpt_header)
434 {
435 	struct spi_nor_flash_parameter *params = nor->params;
436 	struct spi_nor_erase_map *map = &params->erase_map;
437 	struct spi_nor_erase_type *erase_type = map->erase_type;
438 	struct sfdp_bfpt bfpt;
439 	size_t len;
440 	int i, cmd, err;
441 	u32 addr, val;
442 	u16 half;
443 	u8 erase_mask;
444 
445 	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
446 	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
447 		return -EINVAL;
448 
449 	/* Read the Basic Flash Parameter Table. */
450 	len = min_t(size_t, sizeof(bfpt),
451 		    bfpt_header->length * sizeof(u32));
452 	addr = SFDP_PARAM_HEADER_PTP(bfpt_header);
453 	memset(&bfpt, 0, sizeof(bfpt));
454 	err = spi_nor_read_sfdp_dma_unsafe(nor,  addr, len, &bfpt);
455 	if (err < 0)
456 		return err;
457 
458 	/* Fix endianness of the BFPT DWORDs. */
459 	le32_to_cpu_array(bfpt.dwords, BFPT_DWORD_MAX);
460 
461 	/* Number of address bytes. */
462 	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
463 	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
464 	case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:
465 		nor->addr_width = 3;
466 		break;
467 
468 	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
469 		nor->addr_width = 4;
470 		break;
471 
472 	default:
473 		break;
474 	}
475 
476 	/* Flash Memory Density (in bits). */
477 	val = bfpt.dwords[BFPT_DWORD(2)];
478 	if (val & BIT(31)) {
479 		val &= ~BIT(31);
480 
481 		/*
482 		 * Prevent overflows on params->size. Anyway, a NOR of 2^64
483 		 * bits is unlikely to exist so this error probably means
484 		 * the BFPT we are reading is corrupted/wrong.
485 		 */
486 		if (val > 63)
487 			return -EINVAL;
488 
489 		params->size = 1ULL << val;
490 	} else {
491 		params->size = val + 1;
492 	}
493 	params->size >>= 3; /* Convert to bytes. */
494 
495 	/* Fast Read settings. */
496 	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
497 		const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
498 		struct spi_nor_read_command *read;
499 
500 		if (!(bfpt.dwords[rd->supported_dword] & rd->supported_bit)) {
501 			params->hwcaps.mask &= ~rd->hwcaps;
502 			continue;
503 		}
504 
505 		params->hwcaps.mask |= rd->hwcaps;
506 		cmd = spi_nor_hwcaps_read2cmd(rd->hwcaps);
507 		read = &params->reads[cmd];
508 		half = bfpt.dwords[rd->settings_dword] >> rd->settings_shift;
509 		spi_nor_set_read_settings_from_bfpt(read, half, rd->proto);
510 	}
511 
512 	/*
513 	 * Sector Erase settings. Reinitialize the uniform erase map using the
514 	 * Erase Types defined in the bfpt table.
515 	 */
516 	erase_mask = 0;
517 	memset(&params->erase_map, 0, sizeof(params->erase_map));
518 	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_erases); i++) {
519 		const struct sfdp_bfpt_erase *er = &sfdp_bfpt_erases[i];
520 		u32 erasesize;
521 		u8 opcode;
522 
523 		half = bfpt.dwords[er->dword] >> er->shift;
524 		erasesize = half & 0xff;
525 
526 		/* erasesize == 0 means this Erase Type is not supported. */
527 		if (!erasesize)
528 			continue;
529 
530 		erasesize = 1U << erasesize;
531 		opcode = (half >> 8) & 0xff;
532 		erase_mask |= BIT(i);
533 		spi_nor_set_erase_settings_from_bfpt(&erase_type[i], erasesize,
534 						     opcode, i);
535 	}
536 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
537 	/*
538 	 * Sort all the map's Erase Types in ascending order with the smallest
539 	 * erase size being the first member in the erase_type array.
540 	 */
541 	sort(erase_type, SNOR_ERASE_TYPE_MAX, sizeof(erase_type[0]),
542 	     spi_nor_map_cmp_erase_type, NULL);
543 	/*
544 	 * Sort the erase types in the uniform region in order to update the
545 	 * uniform_erase_type bitmask. The bitmask will be used later on when
546 	 * selecting the uniform erase.
547 	 */
548 	spi_nor_regions_sort_erase_types(map);
549 	map->uniform_erase_type = map->uniform_region.offset &
550 				  SNOR_ERASE_TYPE_MASK;
551 
552 	/* Stop here if not JESD216 rev A or later. */
553 	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216)
554 		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
555 
556 	/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
557 	val = bfpt.dwords[BFPT_DWORD(11)];
558 	val &= BFPT_DWORD11_PAGE_SIZE_MASK;
559 	val >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
560 	params->page_size = 1U << val;
561 
562 	/* Quad Enable Requirements. */
563 	switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
564 	case BFPT_DWORD15_QER_NONE:
565 		params->quad_enable = NULL;
566 		break;
567 
568 	case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
569 		/*
570 		 * Writing only one byte to the Status Register has the
571 		 * side-effect of clearing Status Register 2.
572 		 */
573 	case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
574 		/*
575 		 * Read Configuration Register (35h) instruction is not
576 		 * supported.
577 		 */
578 		nor->flags |= SNOR_F_HAS_16BIT_SR | SNOR_F_NO_READ_CR;
579 		params->quad_enable = spi_nor_sr2_bit1_quad_enable;
580 		break;
581 
582 	case BFPT_DWORD15_QER_SR1_BIT6:
583 		nor->flags &= ~SNOR_F_HAS_16BIT_SR;
584 		params->quad_enable = spi_nor_sr1_bit6_quad_enable;
585 		break;
586 
587 	case BFPT_DWORD15_QER_SR2_BIT7:
588 		nor->flags &= ~SNOR_F_HAS_16BIT_SR;
589 		params->quad_enable = spi_nor_sr2_bit7_quad_enable;
590 		break;
591 
592 	case BFPT_DWORD15_QER_SR2_BIT1:
593 		/*
594 		 * JESD216 rev B or later does not specify if writing only one
595 		 * byte to the Status Register clears or not the Status
596 		 * Register 2, so let's be cautious and keep the default
597 		 * assumption of a 16-bit Write Status (01h) command.
598 		 */
599 		nor->flags |= SNOR_F_HAS_16BIT_SR;
600 
601 		params->quad_enable = spi_nor_sr2_bit1_quad_enable;
602 		break;
603 
604 	default:
605 		dev_dbg(nor->dev, "BFPT QER reserved value used\n");
606 		break;
607 	}
608 
609 	/* Soft Reset support. */
610 	if (bfpt.dwords[BFPT_DWORD(16)] & BFPT_DWORD16_SWRST_EN_RST)
611 		nor->flags |= SNOR_F_SOFT_RESET;
612 
613 	/* Stop here if not JESD216 rev C or later. */
614 	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
615 		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
616 
617 	/* 8D-8D-8D command extension. */
618 	switch (bfpt.dwords[BFPT_DWORD(18)] & BFPT_DWORD18_CMD_EXT_MASK) {
619 	case BFPT_DWORD18_CMD_EXT_REP:
620 		nor->cmd_ext_type = SPI_NOR_EXT_REPEAT;
621 		break;
622 
623 	case BFPT_DWORD18_CMD_EXT_INV:
624 		nor->cmd_ext_type = SPI_NOR_EXT_INVERT;
625 		break;
626 
627 	case BFPT_DWORD18_CMD_EXT_RES:
628 		dev_dbg(nor->dev, "Reserved command extension used\n");
629 		break;
630 
631 	case BFPT_DWORD18_CMD_EXT_16B:
632 		dev_dbg(nor->dev, "16-bit opcodes not supported\n");
633 		return -EOPNOTSUPP;
634 	}
635 
636 	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
637 }
638 
639 /**
640  * spi_nor_smpt_addr_width() - return the address width used in the
641  *			       configuration detection command.
642  * @nor:	pointer to a 'struct spi_nor'
643  * @settings:	configuration detection command descriptor, dword1
644  */
645 static u8 spi_nor_smpt_addr_width(const struct spi_nor *nor, const u32 settings)
646 {
647 	switch (settings & SMPT_CMD_ADDRESS_LEN_MASK) {
648 	case SMPT_CMD_ADDRESS_LEN_0:
649 		return 0;
650 	case SMPT_CMD_ADDRESS_LEN_3:
651 		return 3;
652 	case SMPT_CMD_ADDRESS_LEN_4:
653 		return 4;
654 	case SMPT_CMD_ADDRESS_LEN_USE_CURRENT:
655 	default:
656 		return nor->addr_width;
657 	}
658 }
659 
660 /**
661  * spi_nor_smpt_read_dummy() - return the configuration detection command read
662  *			       latency, in clock cycles.
663  * @nor:	pointer to a 'struct spi_nor'
664  * @settings:	configuration detection command descriptor, dword1
665  *
666  * Return: the number of dummy cycles for an SMPT read
667  */
668 static u8 spi_nor_smpt_read_dummy(const struct spi_nor *nor, const u32 settings)
669 {
670 	u8 read_dummy = SMPT_CMD_READ_DUMMY(settings);
671 
672 	if (read_dummy == SMPT_CMD_READ_DUMMY_IS_VARIABLE)
673 		return nor->read_dummy;
674 	return read_dummy;
675 }
676 
677 /**
678  * spi_nor_get_map_in_use() - get the configuration map in use
679  * @nor:	pointer to a 'struct spi_nor'
680  * @smpt:	pointer to the sector map parameter table
681  * @smpt_len:	sector map parameter table length
682  *
683  * Return: pointer to the map in use, ERR_PTR(-errno) otherwise.
684  */
685 static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt,
686 					 u8 smpt_len)
687 {
688 	const u32 *ret;
689 	u8 *buf;
690 	u32 addr;
691 	int err;
692 	u8 i;
693 	u8 addr_width, read_opcode, read_dummy;
694 	u8 read_data_mask, map_id;
695 
696 	/* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */
697 	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
698 	if (!buf)
699 		return ERR_PTR(-ENOMEM);
700 
701 	addr_width = nor->addr_width;
702 	read_dummy = nor->read_dummy;
703 	read_opcode = nor->read_opcode;
704 
705 	map_id = 0;
706 	/* Determine if there are any optional Detection Command Descriptors */
707 	for (i = 0; i < smpt_len; i += 2) {
708 		if (smpt[i] & SMPT_DESC_TYPE_MAP)
709 			break;
710 
711 		read_data_mask = SMPT_CMD_READ_DATA(smpt[i]);
712 		nor->addr_width = spi_nor_smpt_addr_width(nor, smpt[i]);
713 		nor->read_dummy = spi_nor_smpt_read_dummy(nor, smpt[i]);
714 		nor->read_opcode = SMPT_CMD_OPCODE(smpt[i]);
715 		addr = smpt[i + 1];
716 
717 		err = spi_nor_read_raw(nor, addr, 1, buf);
718 		if (err) {
719 			ret = ERR_PTR(err);
720 			goto out;
721 		}
722 
723 		/*
724 		 * Build an index value that is used to select the Sector Map
725 		 * Configuration that is currently in use.
726 		 */
727 		map_id = map_id << 1 | !!(*buf & read_data_mask);
728 	}
729 
730 	/*
731 	 * If command descriptors are provided, they always precede map
732 	 * descriptors in the table. There is no need to start the iteration
733 	 * over smpt array all over again.
734 	 *
735 	 * Find the matching configuration map.
736 	 */
737 	ret = ERR_PTR(-EINVAL);
738 	while (i < smpt_len) {
739 		if (SMPT_MAP_ID(smpt[i]) == map_id) {
740 			ret = smpt + i;
741 			break;
742 		}
743 
744 		/*
745 		 * If there are no more configuration map descriptors and no
746 		 * configuration ID matched the configuration identifier, the
747 		 * sector address map is unknown.
748 		 */
749 		if (smpt[i] & SMPT_DESC_END)
750 			break;
751 
752 		/* increment the table index to the next map */
753 		i += SMPT_MAP_REGION_COUNT(smpt[i]) + 1;
754 	}
755 
756 	/* fall through */
757 out:
758 	kfree(buf);
759 	nor->addr_width = addr_width;
760 	nor->read_dummy = read_dummy;
761 	nor->read_opcode = read_opcode;
762 	return ret;
763 }
764 
765 static void spi_nor_region_mark_end(struct spi_nor_erase_region *region)
766 {
767 	region->offset |= SNOR_LAST_REGION;
768 }
769 
770 static void spi_nor_region_mark_overlay(struct spi_nor_erase_region *region)
771 {
772 	region->offset |= SNOR_OVERLAID_REGION;
773 }
774 
775 /**
776  * spi_nor_region_check_overlay() - set overlay bit when the region is overlaid
777  * @region:	pointer to a structure that describes a SPI NOR erase region
778  * @erase:	pointer to a structure that describes a SPI NOR erase type
779  * @erase_type:	erase type bitmask
780  */
781 static void
782 spi_nor_region_check_overlay(struct spi_nor_erase_region *region,
783 			     const struct spi_nor_erase_type *erase,
784 			     const u8 erase_type)
785 {
786 	int i;
787 
788 	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
789 		if (!(erase[i].size && erase_type & BIT(erase[i].idx)))
790 			continue;
791 		if (region->size & erase[i].size_mask) {
792 			spi_nor_region_mark_overlay(region);
793 			return;
794 		}
795 	}
796 }
797 
798 /**
799  * spi_nor_init_non_uniform_erase_map() - initialize the non-uniform erase map
800  * @nor:	pointer to a 'struct spi_nor'
801  * @smpt:	pointer to the sector map parameter table
802  *
803  * Return: 0 on success, -errno otherwise.
804  */
805 static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
806 					      const u32 *smpt)
807 {
808 	struct spi_nor_erase_map *map = &nor->params->erase_map;
809 	struct spi_nor_erase_type *erase = map->erase_type;
810 	struct spi_nor_erase_region *region;
811 	u64 offset;
812 	u32 region_count;
813 	int i, j;
814 	u8 uniform_erase_type, save_uniform_erase_type;
815 	u8 erase_type, regions_erase_type;
816 
817 	region_count = SMPT_MAP_REGION_COUNT(*smpt);
818 	/*
819 	 * The regions will be freed when the driver detaches from the
820 	 * device.
821 	 */
822 	region = devm_kcalloc(nor->dev, region_count, sizeof(*region),
823 			      GFP_KERNEL);
824 	if (!region)
825 		return -ENOMEM;
826 	map->regions = region;
827 
828 	uniform_erase_type = 0xff;
829 	regions_erase_type = 0;
830 	offset = 0;
831 	/* Populate regions. */
832 	for (i = 0; i < region_count; i++) {
833 		j = i + 1; /* index for the region dword */
834 		region[i].size = SMPT_MAP_REGION_SIZE(smpt[j]);
835 		erase_type = SMPT_MAP_REGION_ERASE_TYPE(smpt[j]);
836 		region[i].offset = offset | erase_type;
837 
838 		spi_nor_region_check_overlay(&region[i], erase, erase_type);
839 
840 		/*
841 		 * Save the erase types that are supported in all regions and
842 		 * can erase the entire flash memory.
843 		 */
844 		uniform_erase_type &= erase_type;
845 
846 		/*
847 		 * regions_erase_type mask will indicate all the erase types
848 		 * supported in this configuration map.
849 		 */
850 		regions_erase_type |= erase_type;
851 
852 		offset = (region[i].offset & ~SNOR_ERASE_FLAGS_MASK) +
853 			 region[i].size;
854 	}
855 	spi_nor_region_mark_end(&region[i - 1]);
856 
857 	save_uniform_erase_type = map->uniform_erase_type;
858 	map->uniform_erase_type = spi_nor_sort_erase_mask(map,
859 							  uniform_erase_type);
860 
861 	if (!regions_erase_type) {
862 		/*
863 		 * Roll back to the previous uniform_erase_type mask, SMPT is
864 		 * broken.
865 		 */
866 		map->uniform_erase_type = save_uniform_erase_type;
867 		return -EINVAL;
868 	}
869 
870 	/*
871 	 * BFPT advertises all the erase types supported by all the possible
872 	 * map configurations. Mask out the erase types that are not supported
873 	 * by the current map configuration.
874 	 */
875 	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
876 		if (!(regions_erase_type & BIT(erase[i].idx)))
877 			spi_nor_set_erase_type(&erase[i], 0, 0xFF);
878 
879 	return 0;
880 }
881 
882 /**
883  * spi_nor_parse_smpt() - parse Sector Map Parameter Table
884  * @nor:		pointer to a 'struct spi_nor'
885  * @smpt_header:	sector map parameter table header
886  *
887  * This table is optional, but when available, we parse it to identify the
888  * location and size of sectors within the main data array of the flash memory
889  * device and to identify which Erase Types are supported by each sector.
890  *
891  * Return: 0 on success, -errno otherwise.
892  */
893 static int spi_nor_parse_smpt(struct spi_nor *nor,
894 			      const struct sfdp_parameter_header *smpt_header)
895 {
896 	const u32 *sector_map;
897 	u32 *smpt;
898 	size_t len;
899 	u32 addr;
900 	int ret;
901 
902 	/* Read the Sector Map Parameter Table. */
903 	len = smpt_header->length * sizeof(*smpt);
904 	smpt = kmalloc(len, GFP_KERNEL);
905 	if (!smpt)
906 		return -ENOMEM;
907 
908 	addr = SFDP_PARAM_HEADER_PTP(smpt_header);
909 	ret = spi_nor_read_sfdp(nor, addr, len, smpt);
910 	if (ret)
911 		goto out;
912 
913 	/* Fix endianness of the SMPT DWORDs. */
914 	le32_to_cpu_array(smpt, smpt_header->length);
915 
916 	sector_map = spi_nor_get_map_in_use(nor, smpt, smpt_header->length);
917 	if (IS_ERR(sector_map)) {
918 		ret = PTR_ERR(sector_map);
919 		goto out;
920 	}
921 
922 	ret = spi_nor_init_non_uniform_erase_map(nor, sector_map);
923 	if (ret)
924 		goto out;
925 
926 	spi_nor_regions_sort_erase_types(&nor->params->erase_map);
927 	/* fall through */
928 out:
929 	kfree(smpt);
930 	return ret;
931 }
932 
933 /**
934  * spi_nor_parse_4bait() - parse the 4-Byte Address Instruction Table
935  * @nor:		pointer to a 'struct spi_nor'.
936  * @param_header:	pointer to the 'struct sfdp_parameter_header' describing
937  *			the 4-Byte Address Instruction Table length and version.
938  *
939  * Return: 0 on success, -errno otherwise.
940  */
941 static int spi_nor_parse_4bait(struct spi_nor *nor,
942 			       const struct sfdp_parameter_header *param_header)
943 {
944 	static const struct sfdp_4bait reads[] = {
945 		{ SNOR_HWCAPS_READ,		BIT(0) },
946 		{ SNOR_HWCAPS_READ_FAST,	BIT(1) },
947 		{ SNOR_HWCAPS_READ_1_1_2,	BIT(2) },
948 		{ SNOR_HWCAPS_READ_1_2_2,	BIT(3) },
949 		{ SNOR_HWCAPS_READ_1_1_4,	BIT(4) },
950 		{ SNOR_HWCAPS_READ_1_4_4,	BIT(5) },
951 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	BIT(13) },
952 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	BIT(14) },
953 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	BIT(15) },
954 	};
955 	static const struct sfdp_4bait programs[] = {
956 		{ SNOR_HWCAPS_PP,		BIT(6) },
957 		{ SNOR_HWCAPS_PP_1_1_4,		BIT(7) },
958 		{ SNOR_HWCAPS_PP_1_4_4,		BIT(8) },
959 	};
960 	static const struct sfdp_4bait erases[SNOR_ERASE_TYPE_MAX] = {
961 		{ 0u /* not used */,		BIT(9) },
962 		{ 0u /* not used */,		BIT(10) },
963 		{ 0u /* not used */,		BIT(11) },
964 		{ 0u /* not used */,		BIT(12) },
965 	};
966 	struct spi_nor_flash_parameter *params = nor->params;
967 	struct spi_nor_pp_command *params_pp = params->page_programs;
968 	struct spi_nor_erase_map *map = &params->erase_map;
969 	struct spi_nor_erase_type *erase_type = map->erase_type;
970 	u32 *dwords;
971 	size_t len;
972 	u32 addr, discard_hwcaps, read_hwcaps, pp_hwcaps, erase_mask;
973 	int i, ret;
974 
975 	if (param_header->major != SFDP_JESD216_MAJOR ||
976 	    param_header->length < SFDP_4BAIT_DWORD_MAX)
977 		return -EINVAL;
978 
979 	/* Read the 4-byte Address Instruction Table. */
980 	len = sizeof(*dwords) * SFDP_4BAIT_DWORD_MAX;
981 
982 	/* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */
983 	dwords = kmalloc(len, GFP_KERNEL);
984 	if (!dwords)
985 		return -ENOMEM;
986 
987 	addr = SFDP_PARAM_HEADER_PTP(param_header);
988 	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
989 	if (ret)
990 		goto out;
991 
992 	/* Fix endianness of the 4BAIT DWORDs. */
993 	le32_to_cpu_array(dwords, SFDP_4BAIT_DWORD_MAX);
994 
995 	/*
996 	 * Compute the subset of (Fast) Read commands for which the 4-byte
997 	 * version is supported.
998 	 */
999 	discard_hwcaps = 0;
1000 	read_hwcaps = 0;
1001 	for (i = 0; i < ARRAY_SIZE(reads); i++) {
1002 		const struct sfdp_4bait *read = &reads[i];
1003 
1004 		discard_hwcaps |= read->hwcaps;
1005 		if ((params->hwcaps.mask & read->hwcaps) &&
1006 		    (dwords[0] & read->supported_bit))
1007 			read_hwcaps |= read->hwcaps;
1008 	}
1009 
1010 	/*
1011 	 * Compute the subset of Page Program commands for which the 4-byte
1012 	 * version is supported.
1013 	 */
1014 	pp_hwcaps = 0;
1015 	for (i = 0; i < ARRAY_SIZE(programs); i++) {
1016 		const struct sfdp_4bait *program = &programs[i];
1017 
1018 		/*
1019 		 * The 4 Byte Address Instruction (Optional) Table is the only
1020 		 * SFDP table that indicates support for Page Program Commands.
1021 		 * Bypass the params->hwcaps.mask and consider 4BAIT the biggest
1022 		 * authority for specifying Page Program support.
1023 		 */
1024 		discard_hwcaps |= program->hwcaps;
1025 		if (dwords[0] & program->supported_bit)
1026 			pp_hwcaps |= program->hwcaps;
1027 	}
1028 
1029 	/*
1030 	 * Compute the subset of Sector Erase commands for which the 4-byte
1031 	 * version is supported.
1032 	 */
1033 	erase_mask = 0;
1034 	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1035 		const struct sfdp_4bait *erase = &erases[i];
1036 
1037 		if (dwords[0] & erase->supported_bit)
1038 			erase_mask |= BIT(i);
1039 	}
1040 
1041 	/* Replicate the sort done for the map's erase types in BFPT. */
1042 	erase_mask = spi_nor_sort_erase_mask(map, erase_mask);
1043 
1044 	/*
1045 	 * We need at least one 4-byte op code per read, program and erase
1046 	 * operation; the .read(), .write() and .erase() hooks share the
1047 	 * nor->addr_width value.
1048 	 */
1049 	if (!read_hwcaps || !pp_hwcaps || !erase_mask)
1050 		goto out;
1051 
1052 	/*
1053 	 * Discard all operations from the 4-byte instruction set which are
1054 	 * not supported by this memory.
1055 	 */
1056 	params->hwcaps.mask &= ~discard_hwcaps;
1057 	params->hwcaps.mask |= (read_hwcaps | pp_hwcaps);
1058 
1059 	/* Use the 4-byte address instruction set. */
1060 	for (i = 0; i < SNOR_CMD_READ_MAX; i++) {
1061 		struct spi_nor_read_command *read_cmd = &params->reads[i];
1062 
1063 		read_cmd->opcode = spi_nor_convert_3to4_read(read_cmd->opcode);
1064 	}
1065 
1066 	/* 4BAIT is the only SFDP table that indicates page program support. */
1067 	if (pp_hwcaps & SNOR_HWCAPS_PP) {
1068 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP],
1069 					SPINOR_OP_PP_4B, SNOR_PROTO_1_1_1);
1070 		/*
1071 		 * Since xSPI Page Program opcode is backward compatible with
1072 		 * Legacy SPI, use Legacy SPI opcode there as well.
1073 		 */
1074 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_8_8_8_DTR],
1075 					SPINOR_OP_PP_4B, SNOR_PROTO_8_8_8_DTR);
1076 	}
1077 	if (pp_hwcaps & SNOR_HWCAPS_PP_1_1_4)
1078 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_1_4],
1079 					SPINOR_OP_PP_1_1_4_4B,
1080 					SNOR_PROTO_1_1_4);
1081 	if (pp_hwcaps & SNOR_HWCAPS_PP_1_4_4)
1082 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_4_4],
1083 					SPINOR_OP_PP_1_4_4_4B,
1084 					SNOR_PROTO_1_4_4);
1085 
1086 	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1087 		if (erase_mask & BIT(i))
1088 			erase_type[i].opcode = (dwords[1] >>
1089 						erase_type[i].idx * 8) & 0xFF;
1090 		else
1091 			spi_nor_set_erase_type(&erase_type[i], 0u, 0xFF);
1092 	}
1093 
1094 	/*
1095 	 * We set SNOR_F_HAS_4BAIT in order to skip spi_nor_set_4byte_opcodes()
1096 	 * later because we already did the conversion to 4byte opcodes. Also,
1097 	 * this latest function implements a legacy quirk for the erase size of
1098 	 * Spansion memory. However this quirk is no longer needed with new
1099 	 * SFDP compliant memories.
1100 	 */
1101 	nor->addr_width = 4;
1102 	nor->flags |= SNOR_F_4B_OPCODES | SNOR_F_HAS_4BAIT;
1103 
1104 	/* fall through */
1105 out:
1106 	kfree(dwords);
1107 	return ret;
1108 }
1109 
1110 #define PROFILE1_DWORD1_RDSR_ADDR_BYTES		BIT(29)
1111 #define PROFILE1_DWORD1_RDSR_DUMMY		BIT(28)
1112 #define PROFILE1_DWORD1_RD_FAST_CMD		GENMASK(15, 8)
1113 #define PROFILE1_DWORD4_DUMMY_200MHZ		GENMASK(11, 7)
1114 #define PROFILE1_DWORD5_DUMMY_166MHZ		GENMASK(31, 27)
1115 #define PROFILE1_DWORD5_DUMMY_133MHZ		GENMASK(21, 17)
1116 #define PROFILE1_DWORD5_DUMMY_100MHZ		GENMASK(11, 7)
1117 
1118 /**
1119  * spi_nor_parse_profile1() - parse the xSPI Profile 1.0 table
1120  * @nor:		pointer to a 'struct spi_nor'
1121  * @profile1_header:	pointer to the 'struct sfdp_parameter_header' describing
1122  *			the Profile 1.0 Table length and version.
1123  *
1124  * Return: 0 on success, -errno otherwise.
1125  */
1126 static int spi_nor_parse_profile1(struct spi_nor *nor,
1127 				  const struct sfdp_parameter_header *profile1_header)
1128 {
1129 	u32 *dwords, addr;
1130 	size_t len;
1131 	int ret;
1132 	u8 dummy, opcode;
1133 
1134 	len = profile1_header->length * sizeof(*dwords);
1135 	dwords = kmalloc(len, GFP_KERNEL);
1136 	if (!dwords)
1137 		return -ENOMEM;
1138 
1139 	addr = SFDP_PARAM_HEADER_PTP(profile1_header);
1140 	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
1141 	if (ret)
1142 		goto out;
1143 
1144 	le32_to_cpu_array(dwords, profile1_header->length);
1145 
1146 	/* Get 8D-8D-8D fast read opcode and dummy cycles. */
1147 	opcode = FIELD_GET(PROFILE1_DWORD1_RD_FAST_CMD, dwords[0]);
1148 
1149 	 /* Set the Read Status Register dummy cycles and dummy address bytes. */
1150 	if (dwords[0] & PROFILE1_DWORD1_RDSR_DUMMY)
1151 		nor->params->rdsr_dummy = 8;
1152 	else
1153 		nor->params->rdsr_dummy = 4;
1154 
1155 	if (dwords[0] & PROFILE1_DWORD1_RDSR_ADDR_BYTES)
1156 		nor->params->rdsr_addr_nbytes = 4;
1157 	else
1158 		nor->params->rdsr_addr_nbytes = 0;
1159 
1160 	/*
1161 	 * We don't know what speed the controller is running at. Find the
1162 	 * dummy cycles for the fastest frequency the flash can run at to be
1163 	 * sure we are never short of dummy cycles. A value of 0 means the
1164 	 * frequency is not supported.
1165 	 *
1166 	 * Default to PROFILE1_DUMMY_DEFAULT if we don't find anything, and let
1167 	 * flashes set the correct value if needed in their fixup hooks.
1168 	 */
1169 	dummy = FIELD_GET(PROFILE1_DWORD4_DUMMY_200MHZ, dwords[3]);
1170 	if (!dummy)
1171 		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_166MHZ, dwords[4]);
1172 	if (!dummy)
1173 		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_133MHZ, dwords[4]);
1174 	if (!dummy)
1175 		dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_100MHZ, dwords[4]);
1176 	if (!dummy)
1177 		dev_dbg(nor->dev,
1178 			"Can't find dummy cycles from Profile 1.0 table\n");
1179 
1180 	/* Round up to an even value to avoid tripping controllers up. */
1181 	dummy = round_up(dummy, 2);
1182 
1183 	/* Update the fast read settings. */
1184 	spi_nor_set_read_settings(&nor->params->reads[SNOR_CMD_READ_8_8_8_DTR],
1185 				  0, dummy, opcode,
1186 				  SNOR_PROTO_8_8_8_DTR);
1187 
1188 out:
1189 	kfree(dwords);
1190 	return ret;
1191 }
1192 
1193 #define SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE		BIT(31)
1194 
1195 /**
1196  * spi_nor_parse_sccr() - Parse the Status, Control and Configuration Register
1197  *                        Map.
1198  * @nor:		pointer to a 'struct spi_nor'
1199  * @sccr_header:	pointer to the 'struct sfdp_parameter_header' describing
1200  *			the SCCR Map table length and version.
1201  *
1202  * Return: 0 on success, -errno otherwise.
1203  */
1204 static int spi_nor_parse_sccr(struct spi_nor *nor,
1205 			      const struct sfdp_parameter_header *sccr_header)
1206 {
1207 	u32 *dwords, addr;
1208 	size_t len;
1209 	int ret;
1210 
1211 	len = sccr_header->length * sizeof(*dwords);
1212 	dwords = kmalloc(len, GFP_KERNEL);
1213 	if (!dwords)
1214 		return -ENOMEM;
1215 
1216 	addr = SFDP_PARAM_HEADER_PTP(sccr_header);
1217 	ret = spi_nor_read_sfdp(nor, addr, len, dwords);
1218 	if (ret)
1219 		goto out;
1220 
1221 	le32_to_cpu_array(dwords, sccr_header->length);
1222 
1223 	if (FIELD_GET(SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE, dwords[22]))
1224 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
1225 
1226 out:
1227 	kfree(dwords);
1228 	return ret;
1229 }
1230 
1231 /**
1232  * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
1233  * @nor:		pointer to a 'struct spi_nor'
1234  *
1235  * The Serial Flash Discoverable Parameters are described by the JEDEC JESD216
1236  * specification. This is a standard which tends to supported by almost all
1237  * (Q)SPI memory manufacturers. Those hard-coded tables allow us to learn at
1238  * runtime the main parameters needed to perform basic SPI flash operations such
1239  * as Fast Read, Page Program or Sector Erase commands.
1240  *
1241  * Return: 0 on success, -errno otherwise.
1242  */
1243 int spi_nor_parse_sfdp(struct spi_nor *nor)
1244 {
1245 	const struct sfdp_parameter_header *param_header, *bfpt_header;
1246 	struct sfdp_parameter_header *param_headers = NULL;
1247 	struct sfdp_header header;
1248 	struct device *dev = nor->dev;
1249 	struct sfdp *sfdp;
1250 	size_t sfdp_size;
1251 	size_t psize;
1252 	int i, err;
1253 
1254 	/* Get the SFDP header. */
1255 	err = spi_nor_read_sfdp_dma_unsafe(nor, 0, sizeof(header), &header);
1256 	if (err < 0)
1257 		return err;
1258 
1259 	/* Check the SFDP header version. */
1260 	if (le32_to_cpu(header.signature) != SFDP_SIGNATURE ||
1261 	    header.major != SFDP_JESD216_MAJOR)
1262 		return -EINVAL;
1263 
1264 	/*
1265 	 * Verify that the first and only mandatory parameter header is a
1266 	 * Basic Flash Parameter Table header as specified in JESD216.
1267 	 */
1268 	bfpt_header = &header.bfpt_header;
1269 	if (SFDP_PARAM_HEADER_ID(bfpt_header) != SFDP_BFPT_ID ||
1270 	    bfpt_header->major != SFDP_JESD216_MAJOR)
1271 		return -EINVAL;
1272 
1273 	sfdp_size = SFDP_PARAM_HEADER_PTP(bfpt_header) +
1274 		    SFDP_PARAM_HEADER_PARAM_LEN(bfpt_header);
1275 
1276 	/*
1277 	 * Allocate memory then read all parameter headers with a single
1278 	 * Read SFDP command. These parameter headers will actually be parsed
1279 	 * twice: a first time to get the latest revision of the basic flash
1280 	 * parameter table, then a second time to handle the supported optional
1281 	 * tables.
1282 	 * Hence we read the parameter headers once for all to reduce the
1283 	 * processing time. Also we use kmalloc() instead of devm_kmalloc()
1284 	 * because we don't need to keep these parameter headers: the allocated
1285 	 * memory is always released with kfree() before exiting this function.
1286 	 */
1287 	if (header.nph) {
1288 		psize = header.nph * sizeof(*param_headers);
1289 
1290 		param_headers = kmalloc(psize, GFP_KERNEL);
1291 		if (!param_headers)
1292 			return -ENOMEM;
1293 
1294 		err = spi_nor_read_sfdp(nor, sizeof(header),
1295 					psize, param_headers);
1296 		if (err < 0) {
1297 			dev_dbg(dev, "failed to read SFDP parameter headers\n");
1298 			goto exit;
1299 		}
1300 	}
1301 
1302 	/*
1303 	 * Cache the complete SFDP data. It is not (easily) possible to fetch
1304 	 * SFDP after probe time and we need it for the sysfs access.
1305 	 */
1306 	for (i = 0; i < header.nph; i++) {
1307 		param_header = &param_headers[i];
1308 		sfdp_size = max_t(size_t, sfdp_size,
1309 				  SFDP_PARAM_HEADER_PTP(param_header) +
1310 				  SFDP_PARAM_HEADER_PARAM_LEN(param_header));
1311 	}
1312 
1313 	/*
1314 	 * Limit the total size to a reasonable value to avoid allocating too
1315 	 * much memory just of because the flash returned some insane values.
1316 	 */
1317 	if (sfdp_size > PAGE_SIZE) {
1318 		dev_dbg(dev, "SFDP data (%zu) too big, truncating\n",
1319 			sfdp_size);
1320 		sfdp_size = PAGE_SIZE;
1321 	}
1322 
1323 	sfdp = devm_kzalloc(dev, sizeof(*sfdp), GFP_KERNEL);
1324 	if (!sfdp) {
1325 		err = -ENOMEM;
1326 		goto exit;
1327 	}
1328 
1329 	/*
1330 	 * The SFDP is organized in chunks of DWORDs. Thus, in theory, the
1331 	 * sfdp_size should be a multiple of DWORDs. But in case a flash
1332 	 * is not spec compliant, make sure that we have enough space to store
1333 	 * the complete SFDP data.
1334 	 */
1335 	sfdp->num_dwords = DIV_ROUND_UP(sfdp_size, sizeof(*sfdp->dwords));
1336 	sfdp->dwords = devm_kcalloc(dev, sfdp->num_dwords,
1337 				    sizeof(*sfdp->dwords), GFP_KERNEL);
1338 	if (!sfdp->dwords) {
1339 		err = -ENOMEM;
1340 		devm_kfree(dev, sfdp);
1341 		goto exit;
1342 	}
1343 
1344 	err = spi_nor_read_sfdp(nor, 0, sfdp_size, sfdp->dwords);
1345 	if (err < 0) {
1346 		dev_dbg(dev, "failed to read SFDP data\n");
1347 		devm_kfree(dev, sfdp->dwords);
1348 		devm_kfree(dev, sfdp);
1349 		goto exit;
1350 	}
1351 
1352 	nor->sfdp = sfdp;
1353 
1354 	/*
1355 	 * Check other parameter headers to get the latest revision of
1356 	 * the basic flash parameter table.
1357 	 */
1358 	for (i = 0; i < header.nph; i++) {
1359 		param_header = &param_headers[i];
1360 
1361 		if (SFDP_PARAM_HEADER_ID(param_header) == SFDP_BFPT_ID &&
1362 		    param_header->major == SFDP_JESD216_MAJOR &&
1363 		    (param_header->minor > bfpt_header->minor ||
1364 		     (param_header->minor == bfpt_header->minor &&
1365 		      param_header->length > bfpt_header->length)))
1366 			bfpt_header = param_header;
1367 	}
1368 
1369 	err = spi_nor_parse_bfpt(nor, bfpt_header);
1370 	if (err)
1371 		goto exit;
1372 
1373 	/* Parse optional parameter tables. */
1374 	for (i = 0; i < header.nph; i++) {
1375 		param_header = &param_headers[i];
1376 
1377 		switch (SFDP_PARAM_HEADER_ID(param_header)) {
1378 		case SFDP_SECTOR_MAP_ID:
1379 			err = spi_nor_parse_smpt(nor, param_header);
1380 			break;
1381 
1382 		case SFDP_4BAIT_ID:
1383 			err = spi_nor_parse_4bait(nor, param_header);
1384 			break;
1385 
1386 		case SFDP_PROFILE1_ID:
1387 			err = spi_nor_parse_profile1(nor, param_header);
1388 			break;
1389 
1390 		case SFDP_SCCR_MAP_ID:
1391 			err = spi_nor_parse_sccr(nor, param_header);
1392 			break;
1393 
1394 		default:
1395 			break;
1396 		}
1397 
1398 		if (err) {
1399 			dev_warn(dev, "Failed to parse optional parameter table: %04x\n",
1400 				 SFDP_PARAM_HEADER_ID(param_header));
1401 			/*
1402 			 * Let's not drop all information we extracted so far
1403 			 * if optional table parsers fail. In case of failing,
1404 			 * each optional parser is responsible to roll back to
1405 			 * the previously known spi_nor data.
1406 			 */
1407 			err = 0;
1408 		}
1409 	}
1410 
1411 exit:
1412 	kfree(param_headers);
1413 	return err;
1414 }
1415