xref: /linux/drivers/mtd/spi-nor/core.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Based on m25p80.c, by Mike Lavender (mike@steroidmicros.com), with
4  * influence from lart.c (Abraham Van Der Merwe) and mtd_dataflash.c
5  *
6  * Copyright (C) 2005, Intec Automation Inc.
7  * Copyright (C) 2014, Freescale Semiconductor, Inc.
8  */
9 
10 #include <linux/err.h>
11 #include <linux/errno.h>
12 #include <linux/delay.h>
13 #include <linux/device.h>
14 #include <linux/math64.h>
15 #include <linux/module.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/spi-nor.h>
18 #include <linux/mutex.h>
19 #include <linux/of_platform.h>
20 #include <linux/sched/task_stack.h>
21 #include <linux/sizes.h>
22 #include <linux/slab.h>
23 #include <linux/spi/flash.h>
24 
25 #include "core.h"
26 
27 /* Define max times to check status register before we give up. */
28 
29 /*
30  * For everything but full-chip erase; probably could be much smaller, but kept
31  * around for safety for now
32  */
33 #define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
34 
35 /*
36  * For full-chip erase, calibrated to a 2MB flash (M25P16); should be scaled up
37  * for larger flash
38  */
39 #define CHIP_ERASE_2MB_READY_WAIT_JIFFIES	(40UL * HZ)
40 
41 #define SPI_NOR_MAX_ADDR_NBYTES	4
42 
43 #define SPI_NOR_SRST_SLEEP_MIN 200
44 #define SPI_NOR_SRST_SLEEP_MAX 400
45 
46 /**
47  * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
48  *			   extension type.
49  * @nor:		pointer to a 'struct spi_nor'
50  * @op:			pointer to the 'struct spi_mem_op' whose properties
51  *			need to be initialized.
52  *
53  * Right now, only "repeat" and "invert" are supported.
54  *
55  * Return: The opcode extension.
56  */
57 static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
58 			      const struct spi_mem_op *op)
59 {
60 	switch (nor->cmd_ext_type) {
61 	case SPI_NOR_EXT_INVERT:
62 		return ~op->cmd.opcode;
63 
64 	case SPI_NOR_EXT_REPEAT:
65 		return op->cmd.opcode;
66 
67 	default:
68 		dev_err(nor->dev, "Unknown command extension type\n");
69 		return 0;
70 	}
71 }
72 
73 /**
74  * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
75  * @nor:		pointer to a 'struct spi_nor'
76  * @op:			pointer to the 'struct spi_mem_op' whose properties
77  *			need to be initialized.
78  * @proto:		the protocol from which the properties need to be set.
79  */
80 void spi_nor_spimem_setup_op(const struct spi_nor *nor,
81 			     struct spi_mem_op *op,
82 			     const enum spi_nor_protocol proto)
83 {
84 	u8 ext;
85 
86 	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
87 
88 	if (op->addr.nbytes)
89 		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
90 
91 	if (op->dummy.nbytes)
92 		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
93 
94 	if (op->data.nbytes)
95 		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
96 
97 	if (spi_nor_protocol_is_dtr(proto)) {
98 		/*
99 		 * SPIMEM supports mixed DTR modes, but right now we can only
100 		 * have all phases either DTR or STR. IOW, SPIMEM can have
101 		 * something like 4S-4D-4D, but SPI NOR can't. So, set all 4
102 		 * phases to either DTR or STR.
103 		 */
104 		op->cmd.dtr = true;
105 		op->addr.dtr = true;
106 		op->dummy.dtr = true;
107 		op->data.dtr = true;
108 
109 		/* 2 bytes per clock cycle in DTR mode. */
110 		op->dummy.nbytes *= 2;
111 
112 		ext = spi_nor_get_cmd_ext(nor, op);
113 		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
114 		op->cmd.nbytes = 2;
115 	}
116 }
117 
118 /**
119  * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
120  *                           transfer
121  * @nor:        pointer to 'struct spi_nor'
122  * @op:         pointer to 'struct spi_mem_op' template for transfer
123  *
124  * If we have to use the bounce buffer, the data field in @op will be updated.
125  *
126  * Return: true if the bounce buffer is needed, false if not
127  */
128 static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
129 {
130 	/* op->data.buf.in occupies the same memory as op->data.buf.out */
131 	if (object_is_on_stack(op->data.buf.in) ||
132 	    !virt_addr_valid(op->data.buf.in)) {
133 		if (op->data.nbytes > nor->bouncebuf_size)
134 			op->data.nbytes = nor->bouncebuf_size;
135 		op->data.buf.in = nor->bouncebuf;
136 		return true;
137 	}
138 
139 	return false;
140 }
141 
142 /**
143  * spi_nor_spimem_exec_op() - execute a memory operation
144  * @nor:        pointer to 'struct spi_nor'
145  * @op:         pointer to 'struct spi_mem_op' template for transfer
146  *
147  * Return: 0 on success, -error otherwise.
148  */
149 static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
150 {
151 	int error;
152 
153 	error = spi_mem_adjust_op_size(nor->spimem, op);
154 	if (error)
155 		return error;
156 
157 	return spi_mem_exec_op(nor->spimem, op);
158 }
159 
160 int spi_nor_controller_ops_read_reg(struct spi_nor *nor, u8 opcode,
161 				    u8 *buf, size_t len)
162 {
163 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
164 		return -EOPNOTSUPP;
165 
166 	return nor->controller_ops->read_reg(nor, opcode, buf, len);
167 }
168 
169 int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
170 				     const u8 *buf, size_t len)
171 {
172 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
173 		return -EOPNOTSUPP;
174 
175 	return nor->controller_ops->write_reg(nor, opcode, buf, len);
176 }
177 
178 static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
179 {
180 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
181 		return -EOPNOTSUPP;
182 
183 	return nor->controller_ops->erase(nor, offs);
184 }
185 
186 /**
187  * spi_nor_spimem_read_data() - read data from flash's memory region via
188  *                              spi-mem
189  * @nor:        pointer to 'struct spi_nor'
190  * @from:       offset to read from
191  * @len:        number of bytes to read
192  * @buf:        pointer to dst buffer
193  *
194  * Return: number of bytes read successfully, -errno otherwise
195  */
196 static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
197 					size_t len, u8 *buf)
198 {
199 	struct spi_mem_op op =
200 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
201 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, from, 0),
202 			   SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
203 			   SPI_MEM_OP_DATA_IN(len, buf, 0));
204 	bool usebouncebuf;
205 	ssize_t nbytes;
206 	int error;
207 
208 	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
209 
210 	/* convert the dummy cycles to the number of bytes */
211 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
212 	if (spi_nor_protocol_is_dtr(nor->read_proto))
213 		op.dummy.nbytes *= 2;
214 
215 	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
216 
217 	if (nor->dirmap.rdesc) {
218 		nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
219 					     op.data.nbytes, op.data.buf.in);
220 	} else {
221 		error = spi_nor_spimem_exec_op(nor, &op);
222 		if (error)
223 			return error;
224 		nbytes = op.data.nbytes;
225 	}
226 
227 	if (usebouncebuf && nbytes > 0)
228 		memcpy(buf, op.data.buf.in, nbytes);
229 
230 	return nbytes;
231 }
232 
233 /**
234  * spi_nor_read_data() - read data from flash memory
235  * @nor:        pointer to 'struct spi_nor'
236  * @from:       offset to read from
237  * @len:        number of bytes to read
238  * @buf:        pointer to dst buffer
239  *
240  * Return: number of bytes read successfully, -errno otherwise
241  */
242 ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len, u8 *buf)
243 {
244 	if (nor->spimem)
245 		return spi_nor_spimem_read_data(nor, from, len, buf);
246 
247 	return nor->controller_ops->read(nor, from, len, buf);
248 }
249 
250 /**
251  * spi_nor_spimem_write_data() - write data to flash memory via
252  *                               spi-mem
253  * @nor:        pointer to 'struct spi_nor'
254  * @to:         offset to write to
255  * @len:        number of bytes to write
256  * @buf:        pointer to src buffer
257  *
258  * Return: number of bytes written successfully, -errno otherwise
259  */
260 static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
261 					 size_t len, const u8 *buf)
262 {
263 	struct spi_mem_op op =
264 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
265 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, to, 0),
266 			   SPI_MEM_OP_NO_DUMMY,
267 			   SPI_MEM_OP_DATA_OUT(len, buf, 0));
268 	ssize_t nbytes;
269 	int error;
270 
271 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
272 		op.addr.nbytes = 0;
273 
274 	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
275 
276 	if (spi_nor_spimem_bounce(nor, &op))
277 		memcpy(nor->bouncebuf, buf, op.data.nbytes);
278 
279 	if (nor->dirmap.wdesc) {
280 		nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
281 					      op.data.nbytes, op.data.buf.out);
282 	} else {
283 		error = spi_nor_spimem_exec_op(nor, &op);
284 		if (error)
285 			return error;
286 		nbytes = op.data.nbytes;
287 	}
288 
289 	return nbytes;
290 }
291 
292 /**
293  * spi_nor_write_data() - write data to flash memory
294  * @nor:        pointer to 'struct spi_nor'
295  * @to:         offset to write to
296  * @len:        number of bytes to write
297  * @buf:        pointer to src buffer
298  *
299  * Return: number of bytes written successfully, -errno otherwise
300  */
301 ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
302 			   const u8 *buf)
303 {
304 	if (nor->spimem)
305 		return spi_nor_spimem_write_data(nor, to, len, buf);
306 
307 	return nor->controller_ops->write(nor, to, len, buf);
308 }
309 
310 /**
311  * spi_nor_read_any_reg() - read any register from flash memory, nonvolatile or
312  * volatile.
313  * @nor:        pointer to 'struct spi_nor'.
314  * @op:		SPI memory operation. op->data.buf must be DMA-able.
315  * @proto:	SPI protocol to use for the register operation.
316  *
317  * Return: zero on success, -errno otherwise
318  */
319 int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
320 			 enum spi_nor_protocol proto)
321 {
322 	if (!nor->spimem)
323 		return -EOPNOTSUPP;
324 
325 	spi_nor_spimem_setup_op(nor, op, proto);
326 	return spi_nor_spimem_exec_op(nor, op);
327 }
328 
329 /**
330  * spi_nor_write_any_volatile_reg() - write any volatile register to flash
331  * memory.
332  * @nor:        pointer to 'struct spi_nor'
333  * @op:		SPI memory operation. op->data.buf must be DMA-able.
334  * @proto:	SPI protocol to use for the register operation.
335  *
336  * Writing volatile registers are instant according to some manufacturers
337  * (Cypress, Micron) and do not need any status polling.
338  *
339  * Return: zero on success, -errno otherwise
340  */
341 int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
342 				   enum spi_nor_protocol proto)
343 {
344 	int ret;
345 
346 	if (!nor->spimem)
347 		return -EOPNOTSUPP;
348 
349 	ret = spi_nor_write_enable(nor);
350 	if (ret)
351 		return ret;
352 	spi_nor_spimem_setup_op(nor, op, proto);
353 	return spi_nor_spimem_exec_op(nor, op);
354 }
355 
356 /**
357  * spi_nor_write_enable() - Set write enable latch with Write Enable command.
358  * @nor:	pointer to 'struct spi_nor'.
359  *
360  * Return: 0 on success, -errno otherwise.
361  */
362 int spi_nor_write_enable(struct spi_nor *nor)
363 {
364 	int ret;
365 
366 	if (nor->spimem) {
367 		struct spi_mem_op op = SPI_NOR_WREN_OP;
368 
369 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
370 
371 		ret = spi_mem_exec_op(nor->spimem, &op);
372 	} else {
373 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREN,
374 						       NULL, 0);
375 	}
376 
377 	if (ret)
378 		dev_dbg(nor->dev, "error %d on Write Enable\n", ret);
379 
380 	return ret;
381 }
382 
383 /**
384  * spi_nor_write_disable() - Send Write Disable instruction to the chip.
385  * @nor:	pointer to 'struct spi_nor'.
386  *
387  * Return: 0 on success, -errno otherwise.
388  */
389 int spi_nor_write_disable(struct spi_nor *nor)
390 {
391 	int ret;
392 
393 	if (nor->spimem) {
394 		struct spi_mem_op op = SPI_NOR_WRDI_OP;
395 
396 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
397 
398 		ret = spi_mem_exec_op(nor->spimem, &op);
399 	} else {
400 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRDI,
401 						       NULL, 0);
402 	}
403 
404 	if (ret)
405 		dev_dbg(nor->dev, "error %d on Write Disable\n", ret);
406 
407 	return ret;
408 }
409 
410 /**
411  * spi_nor_read_id() - Read the JEDEC ID.
412  * @nor:	pointer to 'struct spi_nor'.
413  * @naddr:	number of address bytes to send. Can be zero if the operation
414  *		does not need to send an address.
415  * @ndummy:	number of dummy bytes to send after an opcode or address. Can
416  *		be zero if the operation does not require dummy bytes.
417  * @id:		pointer to a DMA-able buffer where the value of the JEDEC ID
418  *		will be written.
419  * @proto:	the SPI protocol for register operation.
420  *
421  * Return: 0 on success, -errno otherwise.
422  */
423 int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
424 		    enum spi_nor_protocol proto)
425 {
426 	int ret;
427 
428 	if (nor->spimem) {
429 		struct spi_mem_op op =
430 			SPI_NOR_READID_OP(naddr, ndummy, id, SPI_NOR_MAX_ID_LEN);
431 
432 		spi_nor_spimem_setup_op(nor, &op, proto);
433 		ret = spi_mem_exec_op(nor->spimem, &op);
434 	} else {
435 		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
436 						    SPI_NOR_MAX_ID_LEN);
437 	}
438 	return ret;
439 }
440 
441 /**
442  * spi_nor_read_sr() - Read the Status Register.
443  * @nor:	pointer to 'struct spi_nor'.
444  * @sr:		pointer to a DMA-able buffer where the value of the
445  *              Status Register will be written. Should be at least 2 bytes.
446  *
447  * Return: 0 on success, -errno otherwise.
448  */
449 int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
450 {
451 	int ret;
452 
453 	if (nor->spimem) {
454 		struct spi_mem_op op = SPI_NOR_RDSR_OP(sr);
455 
456 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
457 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
458 			op.dummy.nbytes = nor->params->rdsr_dummy;
459 			/*
460 			 * We don't want to read only one byte in DTR mode. So,
461 			 * read 2 and then discard the second byte.
462 			 */
463 			op.data.nbytes = 2;
464 		}
465 
466 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
467 
468 		ret = spi_mem_exec_op(nor->spimem, &op);
469 	} else {
470 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR, sr,
471 						      1);
472 	}
473 
474 	if (ret)
475 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
476 
477 	return ret;
478 }
479 
480 /**
481  * spi_nor_read_cr() - Read the Configuration Register using the
482  * SPINOR_OP_RDCR (35h) command.
483  * @nor:	pointer to 'struct spi_nor'
484  * @cr:		pointer to a DMA-able buffer where the value of the
485  *              Configuration Register will be written.
486  *
487  * Return: 0 on success, -errno otherwise.
488  */
489 int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
490 {
491 	int ret;
492 
493 	if (nor->spimem) {
494 		struct spi_mem_op op = SPI_NOR_RDCR_OP(cr);
495 
496 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
497 
498 		ret = spi_mem_exec_op(nor->spimem, &op);
499 	} else {
500 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDCR, cr,
501 						      1);
502 	}
503 
504 	if (ret)
505 		dev_dbg(nor->dev, "error %d reading CR\n", ret);
506 
507 	return ret;
508 }
509 
510 /**
511  * spi_nor_set_4byte_addr_mode_en4b_ex4b() - Enter/Exit 4-byte address mode
512  *			using SPINOR_OP_EN4B/SPINOR_OP_EX4B. Typically used by
513  *			Winbond and Macronix.
514  * @nor:	pointer to 'struct spi_nor'.
515  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
516  *		address mode.
517  *
518  * Return: 0 on success, -errno otherwise.
519  */
520 int spi_nor_set_4byte_addr_mode_en4b_ex4b(struct spi_nor *nor, bool enable)
521 {
522 	int ret;
523 
524 	if (nor->spimem) {
525 		struct spi_mem_op op = SPI_NOR_EN4B_EX4B_OP(enable);
526 
527 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
528 
529 		ret = spi_mem_exec_op(nor->spimem, &op);
530 	} else {
531 		ret = spi_nor_controller_ops_write_reg(nor,
532 						       enable ? SPINOR_OP_EN4B :
533 								SPINOR_OP_EX4B,
534 						       NULL, 0);
535 	}
536 
537 	if (ret)
538 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
539 
540 	return ret;
541 }
542 
543 /**
544  * spi_nor_set_4byte_addr_mode_wren_en4b_ex4b() - Set 4-byte address mode using
545  * SPINOR_OP_WREN followed by SPINOR_OP_EN4B or SPINOR_OP_EX4B. Typically used
546  * by ST and Micron flashes.
547  * @nor:	pointer to 'struct spi_nor'.
548  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
549  *		address mode.
550  *
551  * Return: 0 on success, -errno otherwise.
552  */
553 int spi_nor_set_4byte_addr_mode_wren_en4b_ex4b(struct spi_nor *nor, bool enable)
554 {
555 	int ret;
556 
557 	ret = spi_nor_write_enable(nor);
558 	if (ret)
559 		return ret;
560 
561 	ret = spi_nor_set_4byte_addr_mode_en4b_ex4b(nor, enable);
562 	if (ret)
563 		return ret;
564 
565 	return spi_nor_write_disable(nor);
566 }
567 
568 /**
569  * spi_nor_set_4byte_addr_mode_brwr() - Set 4-byte address mode using
570  *			SPINOR_OP_BRWR. Typically used by Spansion flashes.
571  * @nor:	pointer to 'struct spi_nor'.
572  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
573  *		address mode.
574  *
575  * 8-bit volatile bank register used to define A[30:A24] bits. MSB (bit[7]) is
576  * used to enable/disable 4-byte address mode. When MSB is set to ‘1’, 4-byte
577  * address mode is active and A[30:24] bits are don’t care. Write instruction is
578  * SPINOR_OP_BRWR(17h) with 1 byte of data.
579  *
580  * Return: 0 on success, -errno otherwise.
581  */
582 int spi_nor_set_4byte_addr_mode_brwr(struct spi_nor *nor, bool enable)
583 {
584 	int ret;
585 
586 	nor->bouncebuf[0] = enable << 7;
587 
588 	if (nor->spimem) {
589 		struct spi_mem_op op = SPI_NOR_BRWR_OP(nor->bouncebuf);
590 
591 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
592 
593 		ret = spi_mem_exec_op(nor->spimem, &op);
594 	} else {
595 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_BRWR,
596 						       nor->bouncebuf, 1);
597 	}
598 
599 	if (ret)
600 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
601 
602 	return ret;
603 }
604 
605 /**
606  * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
607  * for new commands.
608  * @nor:	pointer to 'struct spi_nor'.
609  *
610  * Return: 1 if ready, 0 if not ready, -errno on errors.
611  */
612 int spi_nor_sr_ready(struct spi_nor *nor)
613 {
614 	int ret;
615 
616 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
617 	if (ret)
618 		return ret;
619 
620 	return !(nor->bouncebuf[0] & SR_WIP);
621 }
622 
623 /**
624  * spi_nor_use_parallel_locking() - Checks if RWW locking scheme shall be used
625  * @nor:	pointer to 'struct spi_nor'.
626  *
627  * Return: true if parallel locking is enabled, false otherwise.
628  */
629 static bool spi_nor_use_parallel_locking(struct spi_nor *nor)
630 {
631 	return nor->flags & SNOR_F_RWW;
632 }
633 
634 /* Locking helpers for status read operations */
635 static int spi_nor_rww_start_rdst(struct spi_nor *nor)
636 {
637 	struct spi_nor_rww *rww = &nor->rww;
638 	int ret = -EAGAIN;
639 
640 	mutex_lock(&nor->lock);
641 
642 	if (rww->ongoing_io || rww->ongoing_rd)
643 		goto busy;
644 
645 	rww->ongoing_io = true;
646 	rww->ongoing_rd = true;
647 	ret = 0;
648 
649 busy:
650 	mutex_unlock(&nor->lock);
651 	return ret;
652 }
653 
654 static void spi_nor_rww_end_rdst(struct spi_nor *nor)
655 {
656 	struct spi_nor_rww *rww = &nor->rww;
657 
658 	mutex_lock(&nor->lock);
659 
660 	rww->ongoing_io = false;
661 	rww->ongoing_rd = false;
662 
663 	mutex_unlock(&nor->lock);
664 }
665 
666 static int spi_nor_lock_rdst(struct spi_nor *nor)
667 {
668 	if (spi_nor_use_parallel_locking(nor))
669 		return spi_nor_rww_start_rdst(nor);
670 
671 	return 0;
672 }
673 
674 static void spi_nor_unlock_rdst(struct spi_nor *nor)
675 {
676 	if (spi_nor_use_parallel_locking(nor)) {
677 		spi_nor_rww_end_rdst(nor);
678 		wake_up(&nor->rww.wait);
679 	}
680 }
681 
682 /**
683  * spi_nor_ready() - Query the flash to see if it is ready for new commands.
684  * @nor:	pointer to 'struct spi_nor'.
685  *
686  * Return: 1 if ready, 0 if not ready, -errno on errors.
687  */
688 static int spi_nor_ready(struct spi_nor *nor)
689 {
690 	int ret;
691 
692 	ret = spi_nor_lock_rdst(nor);
693 	if (ret)
694 		return 0;
695 
696 	/* Flashes might override the standard routine. */
697 	if (nor->params->ready)
698 		ret = nor->params->ready(nor);
699 	else
700 		ret = spi_nor_sr_ready(nor);
701 
702 	spi_nor_unlock_rdst(nor);
703 
704 	return ret;
705 }
706 
707 /**
708  * spi_nor_wait_till_ready_with_timeout() - Service routine to read the
709  * Status Register until ready, or timeout occurs.
710  * @nor:		pointer to "struct spi_nor".
711  * @timeout_jiffies:	jiffies to wait until timeout.
712  *
713  * Return: 0 on success, -errno otherwise.
714  */
715 static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
716 						unsigned long timeout_jiffies)
717 {
718 	unsigned long deadline;
719 	int timeout = 0, ret;
720 
721 	deadline = jiffies + timeout_jiffies;
722 
723 	while (!timeout) {
724 		if (time_after_eq(jiffies, deadline))
725 			timeout = 1;
726 
727 		ret = spi_nor_ready(nor);
728 		if (ret < 0)
729 			return ret;
730 		if (ret)
731 			return 0;
732 
733 		cond_resched();
734 	}
735 
736 	dev_dbg(nor->dev, "flash operation timed out\n");
737 
738 	return -ETIMEDOUT;
739 }
740 
741 /**
742  * spi_nor_wait_till_ready() - Wait for a predefined amount of time for the
743  * flash to be ready, or timeout occurs.
744  * @nor:	pointer to "struct spi_nor".
745  *
746  * Return: 0 on success, -errno otherwise.
747  */
748 int spi_nor_wait_till_ready(struct spi_nor *nor)
749 {
750 	return spi_nor_wait_till_ready_with_timeout(nor,
751 						    DEFAULT_READY_WAIT_JIFFIES);
752 }
753 
754 /**
755  * spi_nor_global_block_unlock() - Unlock Global Block Protection.
756  * @nor:	pointer to 'struct spi_nor'.
757  *
758  * Return: 0 on success, -errno otherwise.
759  */
760 int spi_nor_global_block_unlock(struct spi_nor *nor)
761 {
762 	int ret;
763 
764 	ret = spi_nor_write_enable(nor);
765 	if (ret)
766 		return ret;
767 
768 	if (nor->spimem) {
769 		struct spi_mem_op op = SPI_NOR_GBULK_OP;
770 
771 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
772 
773 		ret = spi_mem_exec_op(nor->spimem, &op);
774 	} else {
775 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_GBULK,
776 						       NULL, 0);
777 	}
778 
779 	if (ret) {
780 		dev_dbg(nor->dev, "error %d on Global Block Unlock\n", ret);
781 		return ret;
782 	}
783 
784 	return spi_nor_wait_till_ready(nor);
785 }
786 
787 /**
788  * spi_nor_write_sr() - Write the Status Register.
789  * @nor:	pointer to 'struct spi_nor'.
790  * @sr:		pointer to DMA-able buffer to write to the Status Register.
791  * @len:	number of bytes to write to the Status Register.
792  *
793  * Return: 0 on success, -errno otherwise.
794  */
795 int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
796 {
797 	int ret;
798 
799 	ret = spi_nor_write_enable(nor);
800 	if (ret)
801 		return ret;
802 
803 	if (nor->spimem) {
804 		struct spi_mem_op op = SPI_NOR_WRSR_OP(sr, len);
805 
806 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
807 
808 		ret = spi_mem_exec_op(nor->spimem, &op);
809 	} else {
810 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR, sr,
811 						       len);
812 	}
813 
814 	if (ret) {
815 		dev_dbg(nor->dev, "error %d writing SR\n", ret);
816 		return ret;
817 	}
818 
819 	return spi_nor_wait_till_ready(nor);
820 }
821 
822 /**
823  * spi_nor_write_sr1_and_check() - Write one byte to the Status Register 1 and
824  * ensure that the byte written match the received value.
825  * @nor:	pointer to a 'struct spi_nor'.
826  * @sr1:	byte value to be written to the Status Register.
827  *
828  * Return: 0 on success, -errno otherwise.
829  */
830 static int spi_nor_write_sr1_and_check(struct spi_nor *nor, u8 sr1)
831 {
832 	int ret;
833 
834 	nor->bouncebuf[0] = sr1;
835 
836 	ret = spi_nor_write_sr(nor, nor->bouncebuf, 1);
837 	if (ret)
838 		return ret;
839 
840 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
841 	if (ret)
842 		return ret;
843 
844 	if (nor->bouncebuf[0] != sr1) {
845 		dev_dbg(nor->dev, "SR1: read back test failed\n");
846 		return -EIO;
847 	}
848 
849 	return 0;
850 }
851 
852 /**
853  * spi_nor_write_16bit_sr_and_check() - Write the Status Register 1 and the
854  * Status Register 2 in one shot. Ensure that the byte written in the Status
855  * Register 1 match the received value, and that the 16-bit Write did not
856  * affect what was already in the Status Register 2.
857  * @nor:	pointer to a 'struct spi_nor'.
858  * @sr1:	byte value to be written to the Status Register 1.
859  *
860  * Return: 0 on success, -errno otherwise.
861  */
862 static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
863 {
864 	int ret;
865 	u8 *sr_cr = nor->bouncebuf;
866 	u8 cr_written;
867 
868 	/* Make sure we don't overwrite the contents of Status Register 2. */
869 	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
870 		ret = spi_nor_read_cr(nor, &sr_cr[1]);
871 		if (ret)
872 			return ret;
873 	} else if (spi_nor_get_protocol_width(nor->read_proto) == 4 &&
874 		   spi_nor_get_protocol_width(nor->write_proto) == 4 &&
875 		   nor->params->quad_enable) {
876 		/*
877 		 * If the Status Register 2 Read command (35h) is not
878 		 * supported, we should at least be sure we don't
879 		 * change the value of the SR2 Quad Enable bit.
880 		 *
881 		 * When the Quad Enable method is set and the buswidth is 4, we
882 		 * can safely assume that the value of the QE bit is one, as a
883 		 * consequence of the nor->params->quad_enable() call.
884 		 *
885 		 * According to the JESD216 revB standard, BFPT DWORDS[15],
886 		 * bits 22:20, the 16-bit Write Status (01h) command is
887 		 * available just for the cases in which the QE bit is
888 		 * described in SR2 at BIT(1).
889 		 */
890 		sr_cr[1] = SR2_QUAD_EN_BIT1;
891 	} else {
892 		sr_cr[1] = 0;
893 	}
894 
895 	sr_cr[0] = sr1;
896 
897 	ret = spi_nor_write_sr(nor, sr_cr, 2);
898 	if (ret)
899 		return ret;
900 
901 	ret = spi_nor_read_sr(nor, sr_cr);
902 	if (ret)
903 		return ret;
904 
905 	if (sr1 != sr_cr[0]) {
906 		dev_dbg(nor->dev, "SR: Read back test failed\n");
907 		return -EIO;
908 	}
909 
910 	if (nor->flags & SNOR_F_NO_READ_CR)
911 		return 0;
912 
913 	cr_written = sr_cr[1];
914 
915 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
916 	if (ret)
917 		return ret;
918 
919 	if (cr_written != sr_cr[1]) {
920 		dev_dbg(nor->dev, "CR: read back test failed\n");
921 		return -EIO;
922 	}
923 
924 	return 0;
925 }
926 
927 /**
928  * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
929  * Configuration Register in one shot. Ensure that the byte written in the
930  * Configuration Register match the received value, and that the 16-bit Write
931  * did not affect what was already in the Status Register 1.
932  * @nor:	pointer to a 'struct spi_nor'.
933  * @cr:		byte value to be written to the Configuration Register.
934  *
935  * Return: 0 on success, -errno otherwise.
936  */
937 int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
938 {
939 	int ret;
940 	u8 *sr_cr = nor->bouncebuf;
941 	u8 sr_written;
942 
943 	/* Keep the current value of the Status Register 1. */
944 	ret = spi_nor_read_sr(nor, sr_cr);
945 	if (ret)
946 		return ret;
947 
948 	sr_cr[1] = cr;
949 
950 	ret = spi_nor_write_sr(nor, sr_cr, 2);
951 	if (ret)
952 		return ret;
953 
954 	sr_written = sr_cr[0];
955 
956 	ret = spi_nor_read_sr(nor, sr_cr);
957 	if (ret)
958 		return ret;
959 
960 	if (sr_written != sr_cr[0]) {
961 		dev_dbg(nor->dev, "SR: Read back test failed\n");
962 		return -EIO;
963 	}
964 
965 	if (nor->flags & SNOR_F_NO_READ_CR)
966 		return 0;
967 
968 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
969 	if (ret)
970 		return ret;
971 
972 	if (cr != sr_cr[1]) {
973 		dev_dbg(nor->dev, "CR: read back test failed\n");
974 		return -EIO;
975 	}
976 
977 	return 0;
978 }
979 
980 /**
981  * spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
982  * the byte written match the received value without affecting other bits in the
983  * Status Register 1 and 2.
984  * @nor:	pointer to a 'struct spi_nor'.
985  * @sr1:	byte value to be written to the Status Register.
986  *
987  * Return: 0 on success, -errno otherwise.
988  */
989 int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)
990 {
991 	if (nor->flags & SNOR_F_HAS_16BIT_SR)
992 		return spi_nor_write_16bit_sr_and_check(nor, sr1);
993 
994 	return spi_nor_write_sr1_and_check(nor, sr1);
995 }
996 
997 /**
998  * spi_nor_write_sr2() - Write the Status Register 2 using the
999  * SPINOR_OP_WRSR2 (3eh) command.
1000  * @nor:	pointer to 'struct spi_nor'.
1001  * @sr2:	pointer to DMA-able buffer to write to the Status Register 2.
1002  *
1003  * Return: 0 on success, -errno otherwise.
1004  */
1005 static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
1006 {
1007 	int ret;
1008 
1009 	ret = spi_nor_write_enable(nor);
1010 	if (ret)
1011 		return ret;
1012 
1013 	if (nor->spimem) {
1014 		struct spi_mem_op op = SPI_NOR_WRSR2_OP(sr2);
1015 
1016 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1017 
1018 		ret = spi_mem_exec_op(nor->spimem, &op);
1019 	} else {
1020 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR2,
1021 						       sr2, 1);
1022 	}
1023 
1024 	if (ret) {
1025 		dev_dbg(nor->dev, "error %d writing SR2\n", ret);
1026 		return ret;
1027 	}
1028 
1029 	return spi_nor_wait_till_ready(nor);
1030 }
1031 
1032 /**
1033  * spi_nor_read_sr2() - Read the Status Register 2 using the
1034  * SPINOR_OP_RDSR2 (3fh) command.
1035  * @nor:	pointer to 'struct spi_nor'.
1036  * @sr2:	pointer to DMA-able buffer where the value of the
1037  *		Status Register 2 will be written.
1038  *
1039  * Return: 0 on success, -errno otherwise.
1040  */
1041 static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
1042 {
1043 	int ret;
1044 
1045 	if (nor->spimem) {
1046 		struct spi_mem_op op = SPI_NOR_RDSR2_OP(sr2);
1047 
1048 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1049 
1050 		ret = spi_mem_exec_op(nor->spimem, &op);
1051 	} else {
1052 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR2, sr2,
1053 						      1);
1054 	}
1055 
1056 	if (ret)
1057 		dev_dbg(nor->dev, "error %d reading SR2\n", ret);
1058 
1059 	return ret;
1060 }
1061 
1062 /**
1063  * spi_nor_erase_die() - Erase the entire die.
1064  * @nor:	pointer to 'struct spi_nor'.
1065  * @addr:	address of the die.
1066  * @die_size:	size of the die.
1067  *
1068  * Return: 0 on success, -errno otherwise.
1069  */
1070 static int spi_nor_erase_die(struct spi_nor *nor, loff_t addr, size_t die_size)
1071 {
1072 	bool multi_die = nor->mtd.size != die_size;
1073 	int ret;
1074 
1075 	dev_dbg(nor->dev, " %lldKiB\n", (long long)(die_size >> 10));
1076 
1077 	if (nor->spimem) {
1078 		struct spi_mem_op op =
1079 			SPI_NOR_DIE_ERASE_OP(nor->params->die_erase_opcode,
1080 					     nor->addr_nbytes, addr, multi_die);
1081 
1082 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1083 
1084 		ret = spi_mem_exec_op(nor->spimem, &op);
1085 	} else {
1086 		if (multi_die)
1087 			return -EOPNOTSUPP;
1088 
1089 		ret = spi_nor_controller_ops_write_reg(nor,
1090 						       SPINOR_OP_CHIP_ERASE,
1091 						       NULL, 0);
1092 	}
1093 
1094 	if (ret)
1095 		dev_dbg(nor->dev, "error %d erasing chip\n", ret);
1096 
1097 	return ret;
1098 }
1099 
1100 static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
1101 {
1102 	size_t i;
1103 
1104 	for (i = 0; i < size; i++)
1105 		if (table[i][0] == opcode)
1106 			return table[i][1];
1107 
1108 	/* No conversion found, keep input op code. */
1109 	return opcode;
1110 }
1111 
1112 u8 spi_nor_convert_3to4_read(u8 opcode)
1113 {
1114 	static const u8 spi_nor_3to4_read[][2] = {
1115 		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
1116 		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
1117 		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
1118 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
1119 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
1120 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
1121 		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
1122 		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
1123 
1124 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
1125 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
1126 		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
1127 	};
1128 
1129 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
1130 				      ARRAY_SIZE(spi_nor_3to4_read));
1131 }
1132 
1133 static u8 spi_nor_convert_3to4_program(u8 opcode)
1134 {
1135 	static const u8 spi_nor_3to4_program[][2] = {
1136 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
1137 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
1138 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
1139 		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
1140 		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
1141 	};
1142 
1143 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
1144 				      ARRAY_SIZE(spi_nor_3to4_program));
1145 }
1146 
1147 static u8 spi_nor_convert_3to4_erase(u8 opcode)
1148 {
1149 	static const u8 spi_nor_3to4_erase[][2] = {
1150 		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
1151 		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
1152 		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
1153 	};
1154 
1155 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
1156 				      ARRAY_SIZE(spi_nor_3to4_erase));
1157 }
1158 
1159 static bool spi_nor_has_uniform_erase(const struct spi_nor *nor)
1160 {
1161 	return !!nor->params->erase_map.uniform_region.erase_mask;
1162 }
1163 
1164 static void spi_nor_set_4byte_opcodes(struct spi_nor *nor)
1165 {
1166 	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
1167 	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
1168 	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
1169 
1170 	if (!spi_nor_has_uniform_erase(nor)) {
1171 		struct spi_nor_erase_map *map = &nor->params->erase_map;
1172 		struct spi_nor_erase_type *erase;
1173 		int i;
1174 
1175 		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1176 			erase = &map->erase_type[i];
1177 			erase->opcode =
1178 				spi_nor_convert_3to4_erase(erase->opcode);
1179 		}
1180 	}
1181 }
1182 
1183 static int spi_nor_prep(struct spi_nor *nor)
1184 {
1185 	int ret = 0;
1186 
1187 	if (nor->controller_ops && nor->controller_ops->prepare)
1188 		ret = nor->controller_ops->prepare(nor);
1189 
1190 	return ret;
1191 }
1192 
1193 static void spi_nor_unprep(struct spi_nor *nor)
1194 {
1195 	if (nor->controller_ops && nor->controller_ops->unprepare)
1196 		nor->controller_ops->unprepare(nor);
1197 }
1198 
1199 static void spi_nor_offset_to_banks(u64 bank_size, loff_t start, size_t len,
1200 				    u8 *first, u8 *last)
1201 {
1202 	/* This is currently safe, the number of banks being very small */
1203 	*first = DIV_ROUND_DOWN_ULL(start, bank_size);
1204 	*last = DIV_ROUND_DOWN_ULL(start + len - 1, bank_size);
1205 }
1206 
1207 /* Generic helpers for internal locking and serialization */
1208 static bool spi_nor_rww_start_io(struct spi_nor *nor)
1209 {
1210 	struct spi_nor_rww *rww = &nor->rww;
1211 	bool start = false;
1212 
1213 	mutex_lock(&nor->lock);
1214 
1215 	if (rww->ongoing_io)
1216 		goto busy;
1217 
1218 	rww->ongoing_io = true;
1219 	start = true;
1220 
1221 busy:
1222 	mutex_unlock(&nor->lock);
1223 	return start;
1224 }
1225 
1226 static void spi_nor_rww_end_io(struct spi_nor *nor)
1227 {
1228 	mutex_lock(&nor->lock);
1229 	nor->rww.ongoing_io = false;
1230 	mutex_unlock(&nor->lock);
1231 }
1232 
1233 static int spi_nor_lock_device(struct spi_nor *nor)
1234 {
1235 	if (!spi_nor_use_parallel_locking(nor))
1236 		return 0;
1237 
1238 	return wait_event_killable(nor->rww.wait, spi_nor_rww_start_io(nor));
1239 }
1240 
1241 static void spi_nor_unlock_device(struct spi_nor *nor)
1242 {
1243 	if (spi_nor_use_parallel_locking(nor)) {
1244 		spi_nor_rww_end_io(nor);
1245 		wake_up(&nor->rww.wait);
1246 	}
1247 }
1248 
1249 /* Generic helpers for internal locking and serialization */
1250 static bool spi_nor_rww_start_exclusive(struct spi_nor *nor)
1251 {
1252 	struct spi_nor_rww *rww = &nor->rww;
1253 	bool start = false;
1254 
1255 	mutex_lock(&nor->lock);
1256 
1257 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1258 		goto busy;
1259 
1260 	rww->ongoing_io = true;
1261 	rww->ongoing_rd = true;
1262 	rww->ongoing_pe = true;
1263 	start = true;
1264 
1265 busy:
1266 	mutex_unlock(&nor->lock);
1267 	return start;
1268 }
1269 
1270 static void spi_nor_rww_end_exclusive(struct spi_nor *nor)
1271 {
1272 	struct spi_nor_rww *rww = &nor->rww;
1273 
1274 	mutex_lock(&nor->lock);
1275 	rww->ongoing_io = false;
1276 	rww->ongoing_rd = false;
1277 	rww->ongoing_pe = false;
1278 	mutex_unlock(&nor->lock);
1279 }
1280 
1281 int spi_nor_prep_and_lock(struct spi_nor *nor)
1282 {
1283 	int ret;
1284 
1285 	ret = spi_nor_prep(nor);
1286 	if (ret)
1287 		return ret;
1288 
1289 	if (!spi_nor_use_parallel_locking(nor))
1290 		mutex_lock(&nor->lock);
1291 	else
1292 		ret = wait_event_killable(nor->rww.wait,
1293 					  spi_nor_rww_start_exclusive(nor));
1294 
1295 	return ret;
1296 }
1297 
1298 void spi_nor_unlock_and_unprep(struct spi_nor *nor)
1299 {
1300 	if (!spi_nor_use_parallel_locking(nor)) {
1301 		mutex_unlock(&nor->lock);
1302 	} else {
1303 		spi_nor_rww_end_exclusive(nor);
1304 		wake_up(&nor->rww.wait);
1305 	}
1306 
1307 	spi_nor_unprep(nor);
1308 }
1309 
1310 /* Internal locking helpers for program and erase operations */
1311 static bool spi_nor_rww_start_pe(struct spi_nor *nor, loff_t start, size_t len)
1312 {
1313 	struct spi_nor_rww *rww = &nor->rww;
1314 	unsigned int used_banks = 0;
1315 	bool started = false;
1316 	u8 first, last;
1317 	int bank;
1318 
1319 	mutex_lock(&nor->lock);
1320 
1321 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1322 		goto busy;
1323 
1324 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1325 	for (bank = first; bank <= last; bank++) {
1326 		if (rww->used_banks & BIT(bank))
1327 			goto busy;
1328 
1329 		used_banks |= BIT(bank);
1330 	}
1331 
1332 	rww->used_banks |= used_banks;
1333 	rww->ongoing_pe = true;
1334 	started = true;
1335 
1336 busy:
1337 	mutex_unlock(&nor->lock);
1338 	return started;
1339 }
1340 
1341 static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
1342 {
1343 	struct spi_nor_rww *rww = &nor->rww;
1344 	u8 first, last;
1345 	int bank;
1346 
1347 	mutex_lock(&nor->lock);
1348 
1349 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1350 	for (bank = first; bank <= last; bank++)
1351 		rww->used_banks &= ~BIT(bank);
1352 
1353 	rww->ongoing_pe = false;
1354 
1355 	mutex_unlock(&nor->lock);
1356 }
1357 
1358 static int spi_nor_prep_and_lock_pe(struct spi_nor *nor, loff_t start, size_t len)
1359 {
1360 	int ret;
1361 
1362 	ret = spi_nor_prep(nor);
1363 	if (ret)
1364 		return ret;
1365 
1366 	if (!spi_nor_use_parallel_locking(nor))
1367 		mutex_lock(&nor->lock);
1368 	else
1369 		ret = wait_event_killable(nor->rww.wait,
1370 					  spi_nor_rww_start_pe(nor, start, len));
1371 
1372 	return ret;
1373 }
1374 
1375 static void spi_nor_unlock_and_unprep_pe(struct spi_nor *nor, loff_t start, size_t len)
1376 {
1377 	if (!spi_nor_use_parallel_locking(nor)) {
1378 		mutex_unlock(&nor->lock);
1379 	} else {
1380 		spi_nor_rww_end_pe(nor, start, len);
1381 		wake_up(&nor->rww.wait);
1382 	}
1383 
1384 	spi_nor_unprep(nor);
1385 }
1386 
1387 /* Internal locking helpers for read operations */
1388 static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
1389 {
1390 	struct spi_nor_rww *rww = &nor->rww;
1391 	unsigned int used_banks = 0;
1392 	bool started = false;
1393 	u8 first, last;
1394 	int bank;
1395 
1396 	mutex_lock(&nor->lock);
1397 
1398 	if (rww->ongoing_io || rww->ongoing_rd)
1399 		goto busy;
1400 
1401 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1402 	for (bank = first; bank <= last; bank++) {
1403 		if (rww->used_banks & BIT(bank))
1404 			goto busy;
1405 
1406 		used_banks |= BIT(bank);
1407 	}
1408 
1409 	rww->used_banks |= used_banks;
1410 	rww->ongoing_io = true;
1411 	rww->ongoing_rd = true;
1412 	started = true;
1413 
1414 busy:
1415 	mutex_unlock(&nor->lock);
1416 	return started;
1417 }
1418 
1419 static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
1420 {
1421 	struct spi_nor_rww *rww = &nor->rww;
1422 	u8 first, last;
1423 	int bank;
1424 
1425 	mutex_lock(&nor->lock);
1426 
1427 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1428 	for (bank = first; bank <= last; bank++)
1429 		nor->rww.used_banks &= ~BIT(bank);
1430 
1431 	rww->ongoing_io = false;
1432 	rww->ongoing_rd = false;
1433 
1434 	mutex_unlock(&nor->lock);
1435 }
1436 
1437 static int spi_nor_prep_and_lock_rd(struct spi_nor *nor, loff_t start, size_t len)
1438 {
1439 	int ret;
1440 
1441 	ret = spi_nor_prep(nor);
1442 	if (ret)
1443 		return ret;
1444 
1445 	if (!spi_nor_use_parallel_locking(nor))
1446 		mutex_lock(&nor->lock);
1447 	else
1448 		ret = wait_event_killable(nor->rww.wait,
1449 					  spi_nor_rww_start_rd(nor, start, len));
1450 
1451 	return ret;
1452 }
1453 
1454 static void spi_nor_unlock_and_unprep_rd(struct spi_nor *nor, loff_t start, size_t len)
1455 {
1456 	if (!spi_nor_use_parallel_locking(nor)) {
1457 		mutex_unlock(&nor->lock);
1458 	} else {
1459 		spi_nor_rww_end_rd(nor, start, len);
1460 		wake_up(&nor->rww.wait);
1461 	}
1462 
1463 	spi_nor_unprep(nor);
1464 }
1465 
1466 static u32 spi_nor_convert_addr(struct spi_nor *nor, loff_t addr)
1467 {
1468 	if (!nor->params->convert_addr)
1469 		return addr;
1470 
1471 	return nor->params->convert_addr(nor, addr);
1472 }
1473 
1474 /*
1475  * Initiate the erasure of a single sector
1476  */
1477 int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
1478 {
1479 	int i;
1480 
1481 	addr = spi_nor_convert_addr(nor, addr);
1482 
1483 	if (nor->spimem) {
1484 		struct spi_mem_op op =
1485 			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
1486 						nor->addr_nbytes, addr);
1487 
1488 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1489 
1490 		return spi_mem_exec_op(nor->spimem, &op);
1491 	} else if (nor->controller_ops->erase) {
1492 		return spi_nor_controller_ops_erase(nor, addr);
1493 	}
1494 
1495 	/*
1496 	 * Default implementation, if driver doesn't have a specialized HW
1497 	 * control
1498 	 */
1499 	for (i = nor->addr_nbytes - 1; i >= 0; i--) {
1500 		nor->bouncebuf[i] = addr & 0xff;
1501 		addr >>= 8;
1502 	}
1503 
1504 	return spi_nor_controller_ops_write_reg(nor, nor->erase_opcode,
1505 						nor->bouncebuf, nor->addr_nbytes);
1506 }
1507 
1508 /**
1509  * spi_nor_div_by_erase_size() - calculate remainder and update new dividend
1510  * @erase:	pointer to a structure that describes a SPI NOR erase type
1511  * @dividend:	dividend value
1512  * @remainder:	pointer to u32 remainder (will be updated)
1513  *
1514  * Return: the result of the division
1515  */
1516 static u64 spi_nor_div_by_erase_size(const struct spi_nor_erase_type *erase,
1517 				     u64 dividend, u32 *remainder)
1518 {
1519 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
1520 	*remainder = (u32)dividend & erase->size_mask;
1521 	return dividend >> erase->size_shift;
1522 }
1523 
1524 /**
1525  * spi_nor_find_best_erase_type() - find the best erase type for the given
1526  *				    offset in the serial flash memory and the
1527  *				    number of bytes to erase. The region in
1528  *				    which the address fits is expected to be
1529  *				    provided.
1530  * @map:	the erase map of the SPI NOR
1531  * @region:	pointer to a structure that describes a SPI NOR erase region
1532  * @addr:	offset in the serial flash memory
1533  * @len:	number of bytes to erase
1534  *
1535  * Return: a pointer to the best fitted erase type, NULL otherwise.
1536  */
1537 static const struct spi_nor_erase_type *
1538 spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
1539 			     const struct spi_nor_erase_region *region,
1540 			     u64 addr, u32 len)
1541 {
1542 	const struct spi_nor_erase_type *erase;
1543 	u32 rem;
1544 	int i;
1545 
1546 	/*
1547 	 * Erase types are ordered by size, with the smallest erase type at
1548 	 * index 0.
1549 	 */
1550 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
1551 		/* Does the erase region support the tested erase type? */
1552 		if (!(region->erase_mask & BIT(i)))
1553 			continue;
1554 
1555 		erase = &map->erase_type[i];
1556 		if (!erase->size)
1557 			continue;
1558 
1559 		/* Alignment is not mandatory for overlaid regions */
1560 		if (region->overlaid && region->size <= len)
1561 			return erase;
1562 
1563 		/* Don't erase more than what the user has asked for. */
1564 		if (erase->size > len)
1565 			continue;
1566 
1567 		spi_nor_div_by_erase_size(erase, addr, &rem);
1568 		if (!rem)
1569 			return erase;
1570 	}
1571 
1572 	return NULL;
1573 }
1574 
1575 /**
1576  * spi_nor_init_erase_cmd() - initialize an erase command
1577  * @region:	pointer to a structure that describes a SPI NOR erase region
1578  * @erase:	pointer to a structure that describes a SPI NOR erase type
1579  *
1580  * Return: the pointer to the allocated erase command, ERR_PTR(-errno)
1581  *	   otherwise.
1582  */
1583 static struct spi_nor_erase_command *
1584 spi_nor_init_erase_cmd(const struct spi_nor_erase_region *region,
1585 		       const struct spi_nor_erase_type *erase)
1586 {
1587 	struct spi_nor_erase_command *cmd;
1588 
1589 	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
1590 	if (!cmd)
1591 		return ERR_PTR(-ENOMEM);
1592 
1593 	INIT_LIST_HEAD(&cmd->list);
1594 	cmd->opcode = erase->opcode;
1595 	cmd->count = 1;
1596 
1597 	if (region->overlaid)
1598 		cmd->size = region->size;
1599 	else
1600 		cmd->size = erase->size;
1601 
1602 	return cmd;
1603 }
1604 
1605 /**
1606  * spi_nor_destroy_erase_cmd_list() - destroy erase command list
1607  * @erase_list:	list of erase commands
1608  */
1609 static void spi_nor_destroy_erase_cmd_list(struct list_head *erase_list)
1610 {
1611 	struct spi_nor_erase_command *cmd, *next;
1612 
1613 	list_for_each_entry_safe(cmd, next, erase_list, list) {
1614 		list_del(&cmd->list);
1615 		kfree(cmd);
1616 	}
1617 }
1618 
1619 /**
1620  * spi_nor_init_erase_cmd_list() - initialize erase command list
1621  * @nor:	pointer to a 'struct spi_nor'
1622  * @erase_list:	list of erase commands to be executed once we validate that the
1623  *		erase can be performed
1624  * @addr:	offset in the serial flash memory
1625  * @len:	number of bytes to erase
1626  *
1627  * Builds the list of best fitted erase commands and verifies if the erase can
1628  * be performed.
1629  *
1630  * Return: 0 on success, -errno otherwise.
1631  */
1632 static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
1633 				       struct list_head *erase_list,
1634 				       u64 addr, u32 len)
1635 {
1636 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
1637 	const struct spi_nor_erase_type *erase, *prev_erase = NULL;
1638 	struct spi_nor_erase_region *region;
1639 	struct spi_nor_erase_command *cmd = NULL;
1640 	u64 region_end;
1641 	unsigned int i;
1642 	int ret = -EINVAL;
1643 
1644 	for (i = 0; i < map->n_regions && len; i++) {
1645 		region = &map->regions[i];
1646 		region_end = region->offset + region->size;
1647 
1648 		while (len && addr >= region->offset && addr < region_end) {
1649 			erase = spi_nor_find_best_erase_type(map, region, addr,
1650 							     len);
1651 			if (!erase)
1652 				goto destroy_erase_cmd_list;
1653 
1654 			if (prev_erase != erase || erase->size != cmd->size ||
1655 			    region->overlaid) {
1656 				cmd = spi_nor_init_erase_cmd(region, erase);
1657 				if (IS_ERR(cmd)) {
1658 					ret = PTR_ERR(cmd);
1659 					goto destroy_erase_cmd_list;
1660 				}
1661 
1662 				list_add_tail(&cmd->list, erase_list);
1663 			} else {
1664 				cmd->count++;
1665 			}
1666 
1667 			len -= cmd->size;
1668 			addr += cmd->size;
1669 			prev_erase = erase;
1670 		}
1671 	}
1672 
1673 	return 0;
1674 
1675 destroy_erase_cmd_list:
1676 	spi_nor_destroy_erase_cmd_list(erase_list);
1677 	return ret;
1678 }
1679 
1680 /**
1681  * spi_nor_erase_multi_sectors() - perform a non-uniform erase
1682  * @nor:	pointer to a 'struct spi_nor'
1683  * @addr:	offset in the serial flash memory
1684  * @len:	number of bytes to erase
1685  *
1686  * Build a list of best fitted erase commands and execute it once we validate
1687  * that the erase can be performed.
1688  *
1689  * Return: 0 on success, -errno otherwise.
1690  */
1691 static int spi_nor_erase_multi_sectors(struct spi_nor *nor, u64 addr, u32 len)
1692 {
1693 	LIST_HEAD(erase_list);
1694 	struct spi_nor_erase_command *cmd, *next;
1695 	int ret;
1696 
1697 	ret = spi_nor_init_erase_cmd_list(nor, &erase_list, addr, len);
1698 	if (ret)
1699 		return ret;
1700 
1701 	list_for_each_entry_safe(cmd, next, &erase_list, list) {
1702 		nor->erase_opcode = cmd->opcode;
1703 		while (cmd->count) {
1704 			dev_vdbg(nor->dev, "erase_cmd->size = 0x%08x, erase_cmd->opcode = 0x%02x, erase_cmd->count = %u\n",
1705 				 cmd->size, cmd->opcode, cmd->count);
1706 
1707 			ret = spi_nor_lock_device(nor);
1708 			if (ret)
1709 				goto destroy_erase_cmd_list;
1710 
1711 			ret = spi_nor_write_enable(nor);
1712 			if (ret) {
1713 				spi_nor_unlock_device(nor);
1714 				goto destroy_erase_cmd_list;
1715 			}
1716 
1717 			ret = spi_nor_erase_sector(nor, addr);
1718 			spi_nor_unlock_device(nor);
1719 			if (ret)
1720 				goto destroy_erase_cmd_list;
1721 
1722 			ret = spi_nor_wait_till_ready(nor);
1723 			if (ret)
1724 				goto destroy_erase_cmd_list;
1725 
1726 			addr += cmd->size;
1727 			cmd->count--;
1728 		}
1729 		list_del(&cmd->list);
1730 		kfree(cmd);
1731 	}
1732 
1733 	return 0;
1734 
1735 destroy_erase_cmd_list:
1736 	spi_nor_destroy_erase_cmd_list(&erase_list);
1737 	return ret;
1738 }
1739 
1740 static int spi_nor_erase_dice(struct spi_nor *nor, loff_t addr,
1741 			      size_t len, size_t die_size)
1742 {
1743 	unsigned long timeout;
1744 	int ret;
1745 
1746 	/*
1747 	 * Scale the timeout linearly with the size of the flash, with
1748 	 * a minimum calibrated to an old 2MB flash. We could try to
1749 	 * pull these from CFI/SFDP, but these values should be good
1750 	 * enough for now.
1751 	 */
1752 	timeout = max(CHIP_ERASE_2MB_READY_WAIT_JIFFIES,
1753 		      CHIP_ERASE_2MB_READY_WAIT_JIFFIES *
1754 		      (unsigned long)(nor->mtd.size / SZ_2M));
1755 
1756 	do {
1757 		ret = spi_nor_lock_device(nor);
1758 		if (ret)
1759 			return ret;
1760 
1761 		ret = spi_nor_write_enable(nor);
1762 		if (ret) {
1763 			spi_nor_unlock_device(nor);
1764 			return ret;
1765 		}
1766 
1767 		ret = spi_nor_erase_die(nor, addr, die_size);
1768 
1769 		spi_nor_unlock_device(nor);
1770 		if (ret)
1771 			return ret;
1772 
1773 		ret = spi_nor_wait_till_ready_with_timeout(nor, timeout);
1774 		if (ret)
1775 			return ret;
1776 
1777 		addr += die_size;
1778 		len -= die_size;
1779 
1780 	} while (len);
1781 
1782 	return 0;
1783 }
1784 
1785 /*
1786  * Erase an address range on the nor chip.  The address range may extend
1787  * one or more erase sectors. Return an error if there is a problem erasing.
1788  */
1789 static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
1790 {
1791 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1792 	u8 n_dice = nor->params->n_dice;
1793 	bool multi_die_erase = false;
1794 	u32 addr, len, rem;
1795 	size_t die_size;
1796 	int ret;
1797 
1798 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
1799 			(long long)instr->len);
1800 
1801 	if (spi_nor_has_uniform_erase(nor)) {
1802 		div_u64_rem(instr->len, mtd->erasesize, &rem);
1803 		if (rem)
1804 			return -EINVAL;
1805 	}
1806 
1807 	addr = instr->addr;
1808 	len = instr->len;
1809 
1810 	if (n_dice) {
1811 		die_size = div_u64(mtd->size, n_dice);
1812 		if (!(len & (die_size - 1)) && !(addr & (die_size - 1)))
1813 			multi_die_erase = true;
1814 	} else {
1815 		die_size = mtd->size;
1816 	}
1817 
1818 	ret = spi_nor_prep_and_lock_pe(nor, instr->addr, instr->len);
1819 	if (ret)
1820 		return ret;
1821 
1822 	/* chip (die) erase? */
1823 	if ((len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) ||
1824 	    multi_die_erase) {
1825 		ret = spi_nor_erase_dice(nor, addr, len, die_size);
1826 		if (ret)
1827 			goto erase_err;
1828 
1829 	/* REVISIT in some cases we could speed up erasing large regions
1830 	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
1831 	 * to use "small sector erase", but that's not always optimal.
1832 	 */
1833 
1834 	/* "sector"-at-a-time erase */
1835 	} else if (spi_nor_has_uniform_erase(nor)) {
1836 		while (len) {
1837 			ret = spi_nor_lock_device(nor);
1838 			if (ret)
1839 				goto erase_err;
1840 
1841 			ret = spi_nor_write_enable(nor);
1842 			if (ret) {
1843 				spi_nor_unlock_device(nor);
1844 				goto erase_err;
1845 			}
1846 
1847 			ret = spi_nor_erase_sector(nor, addr);
1848 			spi_nor_unlock_device(nor);
1849 			if (ret)
1850 				goto erase_err;
1851 
1852 			ret = spi_nor_wait_till_ready(nor);
1853 			if (ret)
1854 				goto erase_err;
1855 
1856 			addr += mtd->erasesize;
1857 			len -= mtd->erasesize;
1858 		}
1859 
1860 	/* erase multiple sectors */
1861 	} else {
1862 		ret = spi_nor_erase_multi_sectors(nor, addr, len);
1863 		if (ret)
1864 			goto erase_err;
1865 	}
1866 
1867 	ret = spi_nor_write_disable(nor);
1868 
1869 erase_err:
1870 	spi_nor_unlock_and_unprep_pe(nor, instr->addr, instr->len);
1871 
1872 	return ret;
1873 }
1874 
1875 /**
1876  * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
1877  * Register 1.
1878  * @nor:	pointer to a 'struct spi_nor'
1879  *
1880  * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
1881  *
1882  * Return: 0 on success, -errno otherwise.
1883  */
1884 int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
1885 {
1886 	int ret;
1887 
1888 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1889 	if (ret)
1890 		return ret;
1891 
1892 	if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
1893 		return 0;
1894 
1895 	nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
1896 
1897 	return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
1898 }
1899 
1900 /**
1901  * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
1902  * Register 2.
1903  * @nor:       pointer to a 'struct spi_nor'.
1904  *
1905  * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
1906  *
1907  * Return: 0 on success, -errno otherwise.
1908  */
1909 int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
1910 {
1911 	int ret;
1912 
1913 	if (nor->flags & SNOR_F_NO_READ_CR)
1914 		return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
1915 
1916 	ret = spi_nor_read_cr(nor, nor->bouncebuf);
1917 	if (ret)
1918 		return ret;
1919 
1920 	if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
1921 		return 0;
1922 
1923 	nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
1924 
1925 	return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
1926 }
1927 
1928 /**
1929  * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
1930  * @nor:	pointer to a 'struct spi_nor'
1931  *
1932  * Set the Quad Enable (QE) bit in the Status Register 2.
1933  *
1934  * This is one of the procedures to set the QE bit described in the SFDP
1935  * (JESD216 rev B) specification but no manufacturer using this procedure has
1936  * been identified yet, hence the name of the function.
1937  *
1938  * Return: 0 on success, -errno otherwise.
1939  */
1940 int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
1941 {
1942 	u8 *sr2 = nor->bouncebuf;
1943 	int ret;
1944 	u8 sr2_written;
1945 
1946 	/* Check current Quad Enable bit value. */
1947 	ret = spi_nor_read_sr2(nor, sr2);
1948 	if (ret)
1949 		return ret;
1950 	if (*sr2 & SR2_QUAD_EN_BIT7)
1951 		return 0;
1952 
1953 	/* Update the Quad Enable bit. */
1954 	*sr2 |= SR2_QUAD_EN_BIT7;
1955 
1956 	ret = spi_nor_write_sr2(nor, sr2);
1957 	if (ret)
1958 		return ret;
1959 
1960 	sr2_written = *sr2;
1961 
1962 	/* Read back and check it. */
1963 	ret = spi_nor_read_sr2(nor, sr2);
1964 	if (ret)
1965 		return ret;
1966 
1967 	if (*sr2 != sr2_written) {
1968 		dev_dbg(nor->dev, "SR2: Read back test failed\n");
1969 		return -EIO;
1970 	}
1971 
1972 	return 0;
1973 }
1974 
1975 static const struct spi_nor_manufacturer *manufacturers[] = {
1976 	&spi_nor_atmel,
1977 	&spi_nor_eon,
1978 	&spi_nor_esmt,
1979 	&spi_nor_everspin,
1980 	&spi_nor_gigadevice,
1981 	&spi_nor_intel,
1982 	&spi_nor_issi,
1983 	&spi_nor_macronix,
1984 	&spi_nor_micron,
1985 	&spi_nor_st,
1986 	&spi_nor_spansion,
1987 	&spi_nor_sst,
1988 	&spi_nor_winbond,
1989 	&spi_nor_xilinx,
1990 	&spi_nor_xmc,
1991 };
1992 
1993 static const struct flash_info spi_nor_generic_flash = {
1994 	.name = "spi-nor-generic",
1995 };
1996 
1997 static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
1998 						 const u8 *id)
1999 {
2000 	const struct flash_info *part;
2001 	unsigned int i, j;
2002 
2003 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
2004 		for (j = 0; j < manufacturers[i]->nparts; j++) {
2005 			part = &manufacturers[i]->parts[j];
2006 			if (part->id &&
2007 			    !memcmp(part->id->bytes, id, part->id->len)) {
2008 				nor->manufacturer = manufacturers[i];
2009 				return part;
2010 			}
2011 		}
2012 	}
2013 
2014 	return NULL;
2015 }
2016 
2017 static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
2018 {
2019 	const struct flash_info *info;
2020 	u8 *id = nor->bouncebuf;
2021 	int ret;
2022 
2023 	ret = spi_nor_read_id(nor, 0, 0, id, nor->reg_proto);
2024 	if (ret) {
2025 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
2026 		return ERR_PTR(ret);
2027 	}
2028 
2029 	/* Cache the complete flash ID. */
2030 	nor->id = devm_kmemdup(nor->dev, id, SPI_NOR_MAX_ID_LEN, GFP_KERNEL);
2031 	if (!nor->id)
2032 		return ERR_PTR(-ENOMEM);
2033 
2034 	info = spi_nor_match_id(nor, id);
2035 
2036 	/* Fallback to a generic flash described only by its SFDP data. */
2037 	if (!info) {
2038 		ret = spi_nor_check_sfdp_signature(nor);
2039 		if (!ret)
2040 			info = &spi_nor_generic_flash;
2041 	}
2042 
2043 	if (!info) {
2044 		dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
2045 			SPI_NOR_MAX_ID_LEN, id);
2046 		return ERR_PTR(-ENODEV);
2047 	}
2048 	return info;
2049 }
2050 
2051 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
2052 			size_t *retlen, u_char *buf)
2053 {
2054 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2055 	loff_t from_lock = from;
2056 	size_t len_lock = len;
2057 	ssize_t ret;
2058 
2059 	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
2060 
2061 	ret = spi_nor_prep_and_lock_rd(nor, from_lock, len_lock);
2062 	if (ret)
2063 		return ret;
2064 
2065 	while (len) {
2066 		loff_t addr = from;
2067 
2068 		addr = spi_nor_convert_addr(nor, addr);
2069 
2070 		ret = spi_nor_read_data(nor, addr, len, buf);
2071 		if (ret == 0) {
2072 			/* We shouldn't see 0-length reads */
2073 			ret = -EIO;
2074 			goto read_err;
2075 		}
2076 		if (ret < 0)
2077 			goto read_err;
2078 
2079 		WARN_ON(ret > len);
2080 		*retlen += ret;
2081 		buf += ret;
2082 		from += ret;
2083 		len -= ret;
2084 	}
2085 	ret = 0;
2086 
2087 read_err:
2088 	spi_nor_unlock_and_unprep_rd(nor, from_lock, len_lock);
2089 
2090 	return ret;
2091 }
2092 
2093 /*
2094  * Write an address range to the nor chip.  Data must be written in
2095  * FLASH_PAGESIZE chunks.  The address range may be any size provided
2096  * it is within the physical boundaries.
2097  */
2098 static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
2099 	size_t *retlen, const u_char *buf)
2100 {
2101 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2102 	size_t page_offset, page_remain, i;
2103 	ssize_t ret;
2104 	u32 page_size = nor->params->page_size;
2105 
2106 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
2107 
2108 	ret = spi_nor_prep_and_lock_pe(nor, to, len);
2109 	if (ret)
2110 		return ret;
2111 
2112 	for (i = 0; i < len; ) {
2113 		ssize_t written;
2114 		loff_t addr = to + i;
2115 
2116 		/*
2117 		 * If page_size is a power of two, the offset can be quickly
2118 		 * calculated with an AND operation. On the other cases we
2119 		 * need to do a modulus operation (more expensive).
2120 		 */
2121 		if (is_power_of_2(page_size)) {
2122 			page_offset = addr & (page_size - 1);
2123 		} else {
2124 			u64 aux = addr;
2125 
2126 			page_offset = do_div(aux, page_size);
2127 		}
2128 		/* the size of data remaining on the first page */
2129 		page_remain = min_t(size_t, page_size - page_offset, len - i);
2130 
2131 		addr = spi_nor_convert_addr(nor, addr);
2132 
2133 		ret = spi_nor_lock_device(nor);
2134 		if (ret)
2135 			goto write_err;
2136 
2137 		ret = spi_nor_write_enable(nor);
2138 		if (ret) {
2139 			spi_nor_unlock_device(nor);
2140 			goto write_err;
2141 		}
2142 
2143 		ret = spi_nor_write_data(nor, addr, page_remain, buf + i);
2144 		spi_nor_unlock_device(nor);
2145 		if (ret < 0)
2146 			goto write_err;
2147 		written = ret;
2148 
2149 		ret = spi_nor_wait_till_ready(nor);
2150 		if (ret)
2151 			goto write_err;
2152 		*retlen += written;
2153 		i += written;
2154 	}
2155 
2156 write_err:
2157 	spi_nor_unlock_and_unprep_pe(nor, to, len);
2158 
2159 	return ret;
2160 }
2161 
2162 static int spi_nor_check(struct spi_nor *nor)
2163 {
2164 	if (!nor->dev ||
2165 	    (!nor->spimem && !nor->controller_ops) ||
2166 	    (!nor->spimem && nor->controller_ops &&
2167 	    (!nor->controller_ops->read ||
2168 	     !nor->controller_ops->write ||
2169 	     !nor->controller_ops->read_reg ||
2170 	     !nor->controller_ops->write_reg))) {
2171 		pr_err("spi-nor: please fill all the necessary fields!\n");
2172 		return -EINVAL;
2173 	}
2174 
2175 	if (nor->spimem && nor->controller_ops) {
2176 		dev_err(nor->dev, "nor->spimem and nor->controller_ops are mutually exclusive, please set just one of them.\n");
2177 		return -EINVAL;
2178 	}
2179 
2180 	return 0;
2181 }
2182 
2183 void
2184 spi_nor_set_read_settings(struct spi_nor_read_command *read,
2185 			  u8 num_mode_clocks,
2186 			  u8 num_wait_states,
2187 			  u8 opcode,
2188 			  enum spi_nor_protocol proto)
2189 {
2190 	read->num_mode_clocks = num_mode_clocks;
2191 	read->num_wait_states = num_wait_states;
2192 	read->opcode = opcode;
2193 	read->proto = proto;
2194 }
2195 
2196 void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
2197 			     enum spi_nor_protocol proto)
2198 {
2199 	pp->opcode = opcode;
2200 	pp->proto = proto;
2201 }
2202 
2203 static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2204 {
2205 	size_t i;
2206 
2207 	for (i = 0; i < size; i++)
2208 		if (table[i][0] == (int)hwcaps)
2209 			return table[i][1];
2210 
2211 	return -EINVAL;
2212 }
2213 
2214 int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2215 {
2216 	static const int hwcaps_read2cmd[][2] = {
2217 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2218 		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2219 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2220 		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2221 		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2222 		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2223 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2224 		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2225 		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2226 		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2227 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2228 		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2229 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2230 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2231 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2232 		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
2233 	};
2234 
2235 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2236 				  ARRAY_SIZE(hwcaps_read2cmd));
2237 }
2238 
2239 int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2240 {
2241 	static const int hwcaps_pp2cmd[][2] = {
2242 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2243 		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2244 		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2245 		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2246 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2247 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2248 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2249 		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
2250 	};
2251 
2252 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2253 				  ARRAY_SIZE(hwcaps_pp2cmd));
2254 }
2255 
2256 /**
2257  * spi_nor_spimem_check_op - check if the operation is supported
2258  *                           by controller
2259  *@nor:        pointer to a 'struct spi_nor'
2260  *@op:         pointer to op template to be checked
2261  *
2262  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2263  */
2264 static int spi_nor_spimem_check_op(struct spi_nor *nor,
2265 				   struct spi_mem_op *op)
2266 {
2267 	/*
2268 	 * First test with 4 address bytes. The opcode itself might
2269 	 * be a 3B addressing opcode but we don't care, because
2270 	 * SPI controller implementation should not check the opcode,
2271 	 * but just the sequence.
2272 	 */
2273 	op->addr.nbytes = 4;
2274 	if (!spi_mem_supports_op(nor->spimem, op)) {
2275 		if (nor->params->size > SZ_16M)
2276 			return -EOPNOTSUPP;
2277 
2278 		/* If flash size <= 16MB, 3 address bytes are sufficient */
2279 		op->addr.nbytes = 3;
2280 		if (!spi_mem_supports_op(nor->spimem, op))
2281 			return -EOPNOTSUPP;
2282 	}
2283 
2284 	return 0;
2285 }
2286 
2287 /**
2288  * spi_nor_spimem_check_readop - check if the read op is supported
2289  *                               by controller
2290  *@nor:         pointer to a 'struct spi_nor'
2291  *@read:        pointer to op template to be checked
2292  *
2293  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2294  */
2295 static int spi_nor_spimem_check_readop(struct spi_nor *nor,
2296 				       const struct spi_nor_read_command *read)
2297 {
2298 	struct spi_mem_op op = SPI_NOR_READ_OP(read->opcode);
2299 
2300 	spi_nor_spimem_setup_op(nor, &op, read->proto);
2301 
2302 	/* convert the dummy cycles to the number of bytes */
2303 	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
2304 			  op.dummy.buswidth / 8;
2305 	if (spi_nor_protocol_is_dtr(nor->read_proto))
2306 		op.dummy.nbytes *= 2;
2307 
2308 	return spi_nor_spimem_check_op(nor, &op);
2309 }
2310 
2311 /**
2312  * spi_nor_spimem_check_pp - check if the page program op is supported
2313  *                           by controller
2314  *@nor:         pointer to a 'struct spi_nor'
2315  *@pp:          pointer to op template to be checked
2316  *
2317  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2318  */
2319 static int spi_nor_spimem_check_pp(struct spi_nor *nor,
2320 				   const struct spi_nor_pp_command *pp)
2321 {
2322 	struct spi_mem_op op = SPI_NOR_PP_OP(pp->opcode);
2323 
2324 	spi_nor_spimem_setup_op(nor, &op, pp->proto);
2325 
2326 	return spi_nor_spimem_check_op(nor, &op);
2327 }
2328 
2329 /**
2330  * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol
2331  *                                based on SPI controller capabilities
2332  * @nor:        pointer to a 'struct spi_nor'
2333  * @hwcaps:     pointer to resulting capabilities after adjusting
2334  *              according to controller and flash's capability
2335  */
2336 static void
2337 spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
2338 {
2339 	struct spi_nor_flash_parameter *params = nor->params;
2340 	unsigned int cap;
2341 
2342 	/* X-X-X modes are not supported yet, mask them all. */
2343 	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
2344 
2345 	/*
2346 	 * If the reset line is broken, we do not want to enter a stateful
2347 	 * mode.
2348 	 */
2349 	if (nor->flags & SNOR_F_BROKEN_RESET)
2350 		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
2351 
2352 	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
2353 		int rdidx, ppidx;
2354 
2355 		if (!(*hwcaps & BIT(cap)))
2356 			continue;
2357 
2358 		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));
2359 		if (rdidx >= 0 &&
2360 		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))
2361 			*hwcaps &= ~BIT(cap);
2362 
2363 		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));
2364 		if (ppidx < 0)
2365 			continue;
2366 
2367 		if (spi_nor_spimem_check_pp(nor,
2368 					    &params->page_programs[ppidx]))
2369 			*hwcaps &= ~BIT(cap);
2370 	}
2371 }
2372 
2373 /**
2374  * spi_nor_set_erase_type() - set a SPI NOR erase type
2375  * @erase:	pointer to a structure that describes a SPI NOR erase type
2376  * @size:	the size of the sector/block erased by the erase type
2377  * @opcode:	the SPI command op code to erase the sector/block
2378  */
2379 void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
2380 			    u8 opcode)
2381 {
2382 	erase->size = size;
2383 	erase->opcode = opcode;
2384 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
2385 	erase->size_shift = ffs(erase->size) - 1;
2386 	erase->size_mask = (1 << erase->size_shift) - 1;
2387 }
2388 
2389 /**
2390  * spi_nor_mask_erase_type() - mask out a SPI NOR erase type
2391  * @erase:	pointer to a structure that describes a SPI NOR erase type
2392  */
2393 void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase)
2394 {
2395 	erase->size = 0;
2396 }
2397 
2398 /**
2399  * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
2400  * @map:		the erase map of the SPI NOR
2401  * @erase_mask:		bitmask encoding erase types that can erase the entire
2402  *			flash memory
2403  * @flash_size:		the spi nor flash memory size
2404  */
2405 void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
2406 				    u8 erase_mask, u64 flash_size)
2407 {
2408 	map->uniform_region.offset = 0;
2409 	map->uniform_region.size = flash_size;
2410 	map->uniform_region.erase_mask = erase_mask;
2411 	map->regions = &map->uniform_region;
2412 	map->n_regions = 1;
2413 }
2414 
2415 int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
2416 			     const struct sfdp_parameter_header *bfpt_header,
2417 			     const struct sfdp_bfpt *bfpt)
2418 {
2419 	int ret;
2420 
2421 	if (nor->manufacturer && nor->manufacturer->fixups &&
2422 	    nor->manufacturer->fixups->post_bfpt) {
2423 		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
2424 							   bfpt);
2425 		if (ret)
2426 			return ret;
2427 	}
2428 
2429 	if (nor->info->fixups && nor->info->fixups->post_bfpt)
2430 		return nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt);
2431 
2432 	return 0;
2433 }
2434 
2435 static int spi_nor_select_read(struct spi_nor *nor,
2436 			       u32 shared_hwcaps)
2437 {
2438 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2439 	const struct spi_nor_read_command *read;
2440 
2441 	if (best_match < 0)
2442 		return -EINVAL;
2443 
2444 	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2445 	if (cmd < 0)
2446 		return -EINVAL;
2447 
2448 	read = &nor->params->reads[cmd];
2449 	nor->read_opcode = read->opcode;
2450 	nor->read_proto = read->proto;
2451 
2452 	/*
2453 	 * In the SPI NOR framework, we don't need to make the difference
2454 	 * between mode clock cycles and wait state clock cycles.
2455 	 * Indeed, the value of the mode clock cycles is used by a QSPI
2456 	 * flash memory to know whether it should enter or leave its 0-4-4
2457 	 * (Continuous Read / XIP) mode.
2458 	 * eXecution In Place is out of the scope of the mtd sub-system.
2459 	 * Hence we choose to merge both mode and wait state clock cycles
2460 	 * into the so called dummy clock cycles.
2461 	 */
2462 	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2463 	return 0;
2464 }
2465 
2466 static int spi_nor_select_pp(struct spi_nor *nor,
2467 			     u32 shared_hwcaps)
2468 {
2469 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2470 	const struct spi_nor_pp_command *pp;
2471 
2472 	if (best_match < 0)
2473 		return -EINVAL;
2474 
2475 	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2476 	if (cmd < 0)
2477 		return -EINVAL;
2478 
2479 	pp = &nor->params->page_programs[cmd];
2480 	nor->program_opcode = pp->opcode;
2481 	nor->write_proto = pp->proto;
2482 	return 0;
2483 }
2484 
2485 /**
2486  * spi_nor_select_uniform_erase() - select optimum uniform erase type
2487  * @map:		the erase map of the SPI NOR
2488  *
2489  * Once the optimum uniform sector erase command is found, disable all the
2490  * other.
2491  *
2492  * Return: pointer to erase type on success, NULL otherwise.
2493  */
2494 static const struct spi_nor_erase_type *
2495 spi_nor_select_uniform_erase(struct spi_nor_erase_map *map)
2496 {
2497 	const struct spi_nor_erase_type *tested_erase, *erase = NULL;
2498 	int i;
2499 	u8 uniform_erase_type = map->uniform_region.erase_mask;
2500 
2501 	/*
2502 	 * Search for the biggest erase size, except for when compiled
2503 	 * to use 4k erases.
2504 	 */
2505 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2506 		if (!(uniform_erase_type & BIT(i)))
2507 			continue;
2508 
2509 		tested_erase = &map->erase_type[i];
2510 
2511 		/* Skip masked erase types. */
2512 		if (!tested_erase->size)
2513 			continue;
2514 
2515 		/*
2516 		 * If the current erase size is the 4k one, stop here,
2517 		 * we have found the right uniform Sector Erase command.
2518 		 */
2519 		if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS) &&
2520 		    tested_erase->size == SZ_4K) {
2521 			erase = tested_erase;
2522 			break;
2523 		}
2524 
2525 		/*
2526 		 * Otherwise, the current erase size is still a valid candidate.
2527 		 * Select the biggest valid candidate.
2528 		 */
2529 		if (!erase && tested_erase->size)
2530 			erase = tested_erase;
2531 			/* keep iterating to find the wanted_size */
2532 	}
2533 
2534 	if (!erase)
2535 		return NULL;
2536 
2537 	/* Disable all other Sector Erase commands. */
2538 	map->uniform_region.erase_mask = BIT(erase - map->erase_type);
2539 	return erase;
2540 }
2541 
2542 static int spi_nor_select_erase(struct spi_nor *nor)
2543 {
2544 	struct spi_nor_erase_map *map = &nor->params->erase_map;
2545 	const struct spi_nor_erase_type *erase = NULL;
2546 	struct mtd_info *mtd = &nor->mtd;
2547 	int i;
2548 
2549 	/*
2550 	 * The previous implementation handling Sector Erase commands assumed
2551 	 * that the SPI flash memory has an uniform layout then used only one
2552 	 * of the supported erase sizes for all Sector Erase commands.
2553 	 * So to be backward compatible, the new implementation also tries to
2554 	 * manage the SPI flash memory as uniform with a single erase sector
2555 	 * size, when possible.
2556 	 */
2557 	if (spi_nor_has_uniform_erase(nor)) {
2558 		erase = spi_nor_select_uniform_erase(map);
2559 		if (!erase)
2560 			return -EINVAL;
2561 		nor->erase_opcode = erase->opcode;
2562 		mtd->erasesize = erase->size;
2563 		return 0;
2564 	}
2565 
2566 	/*
2567 	 * For non-uniform SPI flash memory, set mtd->erasesize to the
2568 	 * maximum erase sector size. No need to set nor->erase_opcode.
2569 	 */
2570 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2571 		if (map->erase_type[i].size) {
2572 			erase = &map->erase_type[i];
2573 			break;
2574 		}
2575 	}
2576 
2577 	if (!erase)
2578 		return -EINVAL;
2579 
2580 	mtd->erasesize = erase->size;
2581 	return 0;
2582 }
2583 
2584 static int spi_nor_default_setup(struct spi_nor *nor,
2585 				 const struct spi_nor_hwcaps *hwcaps)
2586 {
2587 	struct spi_nor_flash_parameter *params = nor->params;
2588 	u32 ignored_mask, shared_mask;
2589 	int err;
2590 
2591 	/*
2592 	 * Keep only the hardware capabilities supported by both the SPI
2593 	 * controller and the SPI flash memory.
2594 	 */
2595 	shared_mask = hwcaps->mask & params->hwcaps.mask;
2596 
2597 	if (nor->spimem) {
2598 		/*
2599 		 * When called from spi_nor_probe(), all caps are set and we
2600 		 * need to discard some of them based on what the SPI
2601 		 * controller actually supports (using spi_mem_supports_op()).
2602 		 */
2603 		spi_nor_spimem_adjust_hwcaps(nor, &shared_mask);
2604 	} else {
2605 		/*
2606 		 * SPI n-n-n protocols are not supported when the SPI
2607 		 * controller directly implements the spi_nor interface.
2608 		 * Yet another reason to switch to spi-mem.
2609 		 */
2610 		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
2611 		if (shared_mask & ignored_mask) {
2612 			dev_dbg(nor->dev,
2613 				"SPI n-n-n protocols are not supported.\n");
2614 			shared_mask &= ~ignored_mask;
2615 		}
2616 	}
2617 
2618 	/* Select the (Fast) Read command. */
2619 	err = spi_nor_select_read(nor, shared_mask);
2620 	if (err) {
2621 		dev_dbg(nor->dev,
2622 			"can't select read settings supported by both the SPI controller and memory.\n");
2623 		return err;
2624 	}
2625 
2626 	/* Select the Page Program command. */
2627 	err = spi_nor_select_pp(nor, shared_mask);
2628 	if (err) {
2629 		dev_dbg(nor->dev,
2630 			"can't select write settings supported by both the SPI controller and memory.\n");
2631 		return err;
2632 	}
2633 
2634 	/* Select the Sector Erase command. */
2635 	err = spi_nor_select_erase(nor);
2636 	if (err) {
2637 		dev_dbg(nor->dev,
2638 			"can't select erase settings supported by both the SPI controller and memory.\n");
2639 		return err;
2640 	}
2641 
2642 	return 0;
2643 }
2644 
2645 static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
2646 {
2647 	if (nor->params->addr_nbytes) {
2648 		nor->addr_nbytes = nor->params->addr_nbytes;
2649 	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
2650 		/*
2651 		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
2652 		 * in this protocol an odd addr_nbytes cannot be used because
2653 		 * then the address phase would only span a cycle and a half.
2654 		 * Half a cycle would be left over. We would then have to start
2655 		 * the dummy phase in the middle of a cycle and so too the data
2656 		 * phase, and we will end the transaction with half a cycle left
2657 		 * over.
2658 		 *
2659 		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
2660 		 * avoid this situation.
2661 		 */
2662 		nor->addr_nbytes = 4;
2663 	} else if (nor->info->addr_nbytes) {
2664 		nor->addr_nbytes = nor->info->addr_nbytes;
2665 	} else {
2666 		nor->addr_nbytes = 3;
2667 	}
2668 
2669 	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
2670 		/* enable 4-byte addressing if the device exceeds 16MiB */
2671 		nor->addr_nbytes = 4;
2672 	}
2673 
2674 	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
2675 		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
2676 			nor->addr_nbytes);
2677 		return -EINVAL;
2678 	}
2679 
2680 	/* Set 4byte opcodes when possible. */
2681 	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
2682 	    !(nor->flags & SNOR_F_HAS_4BAIT))
2683 		spi_nor_set_4byte_opcodes(nor);
2684 
2685 	return 0;
2686 }
2687 
2688 static int spi_nor_setup(struct spi_nor *nor,
2689 			 const struct spi_nor_hwcaps *hwcaps)
2690 {
2691 	int ret;
2692 
2693 	if (nor->params->setup)
2694 		ret = nor->params->setup(nor, hwcaps);
2695 	else
2696 		ret = spi_nor_default_setup(nor, hwcaps);
2697 	if (ret)
2698 		return ret;
2699 
2700 	return spi_nor_set_addr_nbytes(nor);
2701 }
2702 
2703 /**
2704  * spi_nor_manufacturer_init_params() - Initialize the flash's parameters and
2705  * settings based on MFR register and ->default_init() hook.
2706  * @nor:	pointer to a 'struct spi_nor'.
2707  */
2708 static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
2709 {
2710 	if (nor->manufacturer && nor->manufacturer->fixups &&
2711 	    nor->manufacturer->fixups->default_init)
2712 		nor->manufacturer->fixups->default_init(nor);
2713 
2714 	if (nor->info->fixups && nor->info->fixups->default_init)
2715 		nor->info->fixups->default_init(nor);
2716 }
2717 
2718 /**
2719  * spi_nor_no_sfdp_init_params() - Initialize the flash's parameters and
2720  * settings based on nor->info->sfdp_flags. This method should be called only by
2721  * flashes that do not define SFDP tables. If the flash supports SFDP but the
2722  * information is wrong and the settings from this function can not be retrieved
2723  * by parsing SFDP, one should instead use the fixup hooks and update the wrong
2724  * bits.
2725  * @nor:	pointer to a 'struct spi_nor'.
2726  */
2727 static void spi_nor_no_sfdp_init_params(struct spi_nor *nor)
2728 {
2729 	struct spi_nor_flash_parameter *params = nor->params;
2730 	struct spi_nor_erase_map *map = &params->erase_map;
2731 	const struct flash_info *info = nor->info;
2732 	const u8 no_sfdp_flags = info->no_sfdp_flags;
2733 	u8 i, erase_mask;
2734 
2735 	if (no_sfdp_flags & SPI_NOR_DUAL_READ) {
2736 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2737 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2738 					  0, 8, SPINOR_OP_READ_1_1_2,
2739 					  SNOR_PROTO_1_1_2);
2740 	}
2741 
2742 	if (no_sfdp_flags & SPI_NOR_QUAD_READ) {
2743 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2744 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2745 					  0, 8, SPINOR_OP_READ_1_1_4,
2746 					  SNOR_PROTO_1_1_4);
2747 	}
2748 
2749 	if (no_sfdp_flags & SPI_NOR_OCTAL_READ) {
2750 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
2751 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
2752 					  0, 8, SPINOR_OP_READ_1_1_8,
2753 					  SNOR_PROTO_1_1_8);
2754 	}
2755 
2756 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_READ) {
2757 		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
2758 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
2759 					  0, 20, SPINOR_OP_READ_FAST,
2760 					  SNOR_PROTO_8_8_8_DTR);
2761 	}
2762 
2763 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_PP) {
2764 		params->hwcaps.mask |= SNOR_HWCAPS_PP_8_8_8_DTR;
2765 		/*
2766 		 * Since xSPI Page Program opcode is backward compatible with
2767 		 * Legacy SPI, use Legacy SPI opcode there as well.
2768 		 */
2769 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
2770 					SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
2771 	}
2772 
2773 	/*
2774 	 * Sector Erase settings. Sort Erase Types in ascending order, with the
2775 	 * smallest erase size starting at BIT(0).
2776 	 */
2777 	erase_mask = 0;
2778 	i = 0;
2779 	if (no_sfdp_flags & SECT_4K) {
2780 		erase_mask |= BIT(i);
2781 		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2782 				       SPINOR_OP_BE_4K);
2783 		i++;
2784 	}
2785 	erase_mask |= BIT(i);
2786 	spi_nor_set_erase_type(&map->erase_type[i],
2787 			       info->sector_size ?: SPI_NOR_DEFAULT_SECTOR_SIZE,
2788 			       SPINOR_OP_SE);
2789 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
2790 }
2791 
2792 /**
2793  * spi_nor_init_flags() - Initialize NOR flags for settings that are not defined
2794  * in the JESD216 SFDP standard, thus can not be retrieved when parsing SFDP.
2795  * @nor:	pointer to a 'struct spi_nor'
2796  */
2797 static void spi_nor_init_flags(struct spi_nor *nor)
2798 {
2799 	struct device_node *np = spi_nor_get_flash_node(nor);
2800 	const u16 flags = nor->info->flags;
2801 
2802 	if (of_property_read_bool(np, "broken-flash-reset"))
2803 		nor->flags |= SNOR_F_BROKEN_RESET;
2804 
2805 	if (of_property_read_bool(np, "no-wp"))
2806 		nor->flags |= SNOR_F_NO_WP;
2807 
2808 	if (flags & SPI_NOR_SWP_IS_VOLATILE)
2809 		nor->flags |= SNOR_F_SWP_IS_VOLATILE;
2810 
2811 	if (flags & SPI_NOR_HAS_LOCK)
2812 		nor->flags |= SNOR_F_HAS_LOCK;
2813 
2814 	if (flags & SPI_NOR_HAS_TB) {
2815 		nor->flags |= SNOR_F_HAS_SR_TB;
2816 		if (flags & SPI_NOR_TB_SR_BIT6)
2817 			nor->flags |= SNOR_F_HAS_SR_TB_BIT6;
2818 	}
2819 
2820 	if (flags & SPI_NOR_4BIT_BP) {
2821 		nor->flags |= SNOR_F_HAS_4BIT_BP;
2822 		if (flags & SPI_NOR_BP3_SR_BIT6)
2823 			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
2824 	}
2825 
2826 	if (flags & SPI_NOR_RWW && nor->params->n_banks > 1 &&
2827 	    !nor->controller_ops)
2828 		nor->flags |= SNOR_F_RWW;
2829 }
2830 
2831 /**
2832  * spi_nor_init_fixup_flags() - Initialize NOR flags for settings that can not
2833  * be discovered by SFDP for this particular flash because the SFDP table that
2834  * indicates this support is not defined in the flash. In case the table for
2835  * this support is defined but has wrong values, one should instead use a
2836  * post_sfdp() hook to set the SNOR_F equivalent flag.
2837  * @nor:       pointer to a 'struct spi_nor'
2838  */
2839 static void spi_nor_init_fixup_flags(struct spi_nor *nor)
2840 {
2841 	const u8 fixup_flags = nor->info->fixup_flags;
2842 
2843 	if (fixup_flags & SPI_NOR_4B_OPCODES)
2844 		nor->flags |= SNOR_F_4B_OPCODES;
2845 
2846 	if (fixup_flags & SPI_NOR_IO_MODE_EN_VOLATILE)
2847 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
2848 }
2849 
2850 /**
2851  * spi_nor_late_init_params() - Late initialization of default flash parameters.
2852  * @nor:	pointer to a 'struct spi_nor'
2853  *
2854  * Used to initialize flash parameters that are not declared in the JESD216
2855  * SFDP standard, or where SFDP tables are not defined at all.
2856  * Will replace the spi_nor_manufacturer_init_params() method.
2857  */
2858 static int spi_nor_late_init_params(struct spi_nor *nor)
2859 {
2860 	struct spi_nor_flash_parameter *params = nor->params;
2861 	int ret;
2862 
2863 	if (nor->manufacturer && nor->manufacturer->fixups &&
2864 	    nor->manufacturer->fixups->late_init) {
2865 		ret = nor->manufacturer->fixups->late_init(nor);
2866 		if (ret)
2867 			return ret;
2868 	}
2869 
2870 	/* Needed by some flashes late_init hooks. */
2871 	spi_nor_init_flags(nor);
2872 
2873 	if (nor->info->fixups && nor->info->fixups->late_init) {
2874 		ret = nor->info->fixups->late_init(nor);
2875 		if (ret)
2876 			return ret;
2877 	}
2878 
2879 	if (!nor->params->die_erase_opcode)
2880 		nor->params->die_erase_opcode = SPINOR_OP_CHIP_ERASE;
2881 
2882 	/* Default method kept for backward compatibility. */
2883 	if (!params->set_4byte_addr_mode)
2884 		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
2885 
2886 	spi_nor_init_fixup_flags(nor);
2887 
2888 	/*
2889 	 * NOR protection support. When locking_ops are not provided, we pick
2890 	 * the default ones.
2891 	 */
2892 	if (nor->flags & SNOR_F_HAS_LOCK && !nor->params->locking_ops)
2893 		spi_nor_init_default_locking_ops(nor);
2894 
2895 	if (params->n_banks > 1)
2896 		params->bank_size = div64_u64(params->size, params->n_banks);
2897 
2898 	return 0;
2899 }
2900 
2901 /**
2902  * spi_nor_sfdp_init_params_deprecated() - Deprecated way of initializing flash
2903  * parameters and settings based on JESD216 SFDP standard.
2904  * @nor:	pointer to a 'struct spi_nor'.
2905  *
2906  * The method has a roll-back mechanism: in case the SFDP parsing fails, the
2907  * legacy flash parameters and settings will be restored.
2908  */
2909 static void spi_nor_sfdp_init_params_deprecated(struct spi_nor *nor)
2910 {
2911 	struct spi_nor_flash_parameter sfdp_params;
2912 
2913 	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
2914 
2915 	if (spi_nor_parse_sfdp(nor)) {
2916 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
2917 		nor->flags &= ~SNOR_F_4B_OPCODES;
2918 	}
2919 }
2920 
2921 /**
2922  * spi_nor_init_params_deprecated() - Deprecated way of initializing flash
2923  * parameters and settings.
2924  * @nor:	pointer to a 'struct spi_nor'.
2925  *
2926  * The method assumes that flash doesn't support SFDP so it initializes flash
2927  * parameters in spi_nor_no_sfdp_init_params() which later on can be overwritten
2928  * when parsing SFDP, if supported.
2929  */
2930 static void spi_nor_init_params_deprecated(struct spi_nor *nor)
2931 {
2932 	spi_nor_no_sfdp_init_params(nor);
2933 
2934 	spi_nor_manufacturer_init_params(nor);
2935 
2936 	if (nor->info->no_sfdp_flags & (SPI_NOR_DUAL_READ |
2937 					SPI_NOR_QUAD_READ |
2938 					SPI_NOR_OCTAL_READ |
2939 					SPI_NOR_OCTAL_DTR_READ))
2940 		spi_nor_sfdp_init_params_deprecated(nor);
2941 }
2942 
2943 /**
2944  * spi_nor_init_default_params() - Default initialization of flash parameters
2945  * and settings. Done for all flashes, regardless is they define SFDP tables
2946  * or not.
2947  * @nor:	pointer to a 'struct spi_nor'.
2948  */
2949 static void spi_nor_init_default_params(struct spi_nor *nor)
2950 {
2951 	struct spi_nor_flash_parameter *params = nor->params;
2952 	const struct flash_info *info = nor->info;
2953 	struct device_node *np = spi_nor_get_flash_node(nor);
2954 
2955 	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
2956 	params->otp.org = info->otp;
2957 
2958 	/* Default to 16-bit Write Status (01h) Command */
2959 	nor->flags |= SNOR_F_HAS_16BIT_SR;
2960 
2961 	/* Set SPI NOR sizes. */
2962 	params->writesize = 1;
2963 	params->size = info->size;
2964 	params->bank_size = params->size;
2965 	params->page_size = info->page_size ?: SPI_NOR_DEFAULT_PAGE_SIZE;
2966 	params->n_banks = info->n_banks ?: SPI_NOR_DEFAULT_N_BANKS;
2967 
2968 	if (!(info->flags & SPI_NOR_NO_FR)) {
2969 		/* Default to Fast Read for DT and non-DT platform devices. */
2970 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
2971 
2972 		/* Mask out Fast Read if not requested at DT instantiation. */
2973 		if (np && !of_property_read_bool(np, "m25p,fast-read"))
2974 			params->hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
2975 	}
2976 
2977 	/* (Fast) Read settings. */
2978 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
2979 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
2980 				  0, 0, SPINOR_OP_READ,
2981 				  SNOR_PROTO_1_1_1);
2982 
2983 	if (params->hwcaps.mask & SNOR_HWCAPS_READ_FAST)
2984 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
2985 					  0, 8, SPINOR_OP_READ_FAST,
2986 					  SNOR_PROTO_1_1_1);
2987 	/* Page Program settings. */
2988 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
2989 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
2990 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
2991 
2992 	if (info->flags & SPI_NOR_QUAD_PP) {
2993 		params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
2994 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
2995 					SPINOR_OP_PP_1_1_4, SNOR_PROTO_1_1_4);
2996 	}
2997 }
2998 
2999 /**
3000  * spi_nor_init_params() - Initialize the flash's parameters and settings.
3001  * @nor:	pointer to a 'struct spi_nor'.
3002  *
3003  * The flash parameters and settings are initialized based on a sequence of
3004  * calls that are ordered by priority:
3005  *
3006  * 1/ Default flash parameters initialization. The initializations are done
3007  *    based on nor->info data:
3008  *		spi_nor_info_init_params()
3009  *
3010  * which can be overwritten by:
3011  * 2/ Manufacturer flash parameters initialization. The initializations are
3012  *    done based on MFR register, or when the decisions can not be done solely
3013  *    based on MFR, by using specific flash_info tweeks, ->default_init():
3014  *		spi_nor_manufacturer_init_params()
3015  *
3016  * which can be overwritten by:
3017  * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
3018  *    should be more accurate that the above.
3019  *		spi_nor_parse_sfdp() or spi_nor_no_sfdp_init_params()
3020  *
3021  *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
3022  *    the flash parameters and settings immediately after parsing the Basic
3023  *    Flash Parameter Table.
3024  *    spi_nor_post_sfdp_fixups() is called after the SFDP tables are parsed.
3025  *    It is used to tweak various flash parameters when information provided
3026  *    by the SFDP tables are wrong.
3027  *
3028  * which can be overwritten by:
3029  * 4/ Late flash parameters initialization, used to initialize flash
3030  * parameters that are not declared in the JESD216 SFDP standard, or where SFDP
3031  * tables are not defined at all.
3032  *		spi_nor_late_init_params()
3033  *
3034  * Return: 0 on success, -errno otherwise.
3035  */
3036 static int spi_nor_init_params(struct spi_nor *nor)
3037 {
3038 	int ret;
3039 
3040 	nor->params = devm_kzalloc(nor->dev, sizeof(*nor->params), GFP_KERNEL);
3041 	if (!nor->params)
3042 		return -ENOMEM;
3043 
3044 	spi_nor_init_default_params(nor);
3045 
3046 	if (spi_nor_needs_sfdp(nor)) {
3047 		ret = spi_nor_parse_sfdp(nor);
3048 		if (ret) {
3049 			dev_err(nor->dev, "BFPT parsing failed. Please consider using SPI_NOR_SKIP_SFDP when declaring the flash\n");
3050 			return ret;
3051 		}
3052 	} else if (nor->info->no_sfdp_flags & SPI_NOR_SKIP_SFDP) {
3053 		spi_nor_no_sfdp_init_params(nor);
3054 	} else {
3055 		spi_nor_init_params_deprecated(nor);
3056 	}
3057 
3058 	return spi_nor_late_init_params(nor);
3059 }
3060 
3061 /** spi_nor_set_octal_dtr() - enable or disable Octal DTR I/O.
3062  * @nor:                 pointer to a 'struct spi_nor'
3063  * @enable:              whether to enable or disable Octal DTR
3064  *
3065  * Return: 0 on success, -errno otherwise.
3066  */
3067 static int spi_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
3068 {
3069 	int ret;
3070 
3071 	if (!nor->params->set_octal_dtr)
3072 		return 0;
3073 
3074 	if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
3075 	      nor->write_proto == SNOR_PROTO_8_8_8_DTR))
3076 		return 0;
3077 
3078 	if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
3079 		return 0;
3080 
3081 	ret = nor->params->set_octal_dtr(nor, enable);
3082 	if (ret)
3083 		return ret;
3084 
3085 	if (enable)
3086 		nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
3087 	else
3088 		nor->reg_proto = SNOR_PROTO_1_1_1;
3089 
3090 	return 0;
3091 }
3092 
3093 /**
3094  * spi_nor_quad_enable() - enable Quad I/O if needed.
3095  * @nor:                pointer to a 'struct spi_nor'
3096  *
3097  * Return: 0 on success, -errno otherwise.
3098  */
3099 static int spi_nor_quad_enable(struct spi_nor *nor)
3100 {
3101 	if (!nor->params->quad_enable)
3102 		return 0;
3103 
3104 	if (!(spi_nor_get_protocol_width(nor->read_proto) == 4 ||
3105 	      spi_nor_get_protocol_width(nor->write_proto) == 4))
3106 		return 0;
3107 
3108 	return nor->params->quad_enable(nor);
3109 }
3110 
3111 /**
3112  * spi_nor_set_4byte_addr_mode() - Set address mode.
3113  * @nor:                pointer to a 'struct spi_nor'.
3114  * @enable:             enable/disable 4 byte address mode.
3115  *
3116  * Return: 0 on success, -errno otherwise.
3117  */
3118 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
3119 {
3120 	struct spi_nor_flash_parameter *params = nor->params;
3121 	int ret;
3122 
3123 	if (enable) {
3124 		/*
3125 		 * If the RESET# pin isn't hooked up properly, or the system
3126 		 * otherwise doesn't perform a reset command in the boot
3127 		 * sequence, it's impossible to 100% protect against unexpected
3128 		 * reboots (e.g., crashes). Warn the user (or hopefully, system
3129 		 * designer) that this is bad.
3130 		 */
3131 		WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
3132 			  "enabling reset hack; may not recover from unexpected reboots\n");
3133 	}
3134 
3135 	ret = params->set_4byte_addr_mode(nor, enable);
3136 	if (ret && ret != -EOPNOTSUPP)
3137 		return ret;
3138 
3139 	if (enable) {
3140 		params->addr_nbytes = 4;
3141 		params->addr_mode_nbytes = 4;
3142 	} else {
3143 		params->addr_nbytes = 3;
3144 		params->addr_mode_nbytes = 3;
3145 	}
3146 
3147 	return 0;
3148 }
3149 
3150 static int spi_nor_init(struct spi_nor *nor)
3151 {
3152 	int err;
3153 
3154 	err = spi_nor_set_octal_dtr(nor, true);
3155 	if (err) {
3156 		dev_dbg(nor->dev, "octal mode not supported\n");
3157 		return err;
3158 	}
3159 
3160 	err = spi_nor_quad_enable(nor);
3161 	if (err) {
3162 		dev_dbg(nor->dev, "quad mode not supported\n");
3163 		return err;
3164 	}
3165 
3166 	/*
3167 	 * Some SPI NOR flashes are write protected by default after a power-on
3168 	 * reset cycle, in order to avoid inadvertent writes during power-up.
3169 	 * Backward compatibility imposes to unlock the entire flash memory
3170 	 * array at power-up by default. Depending on the kernel configuration
3171 	 * (1) do nothing, (2) always unlock the entire flash array or (3)
3172 	 * unlock the entire flash array only when the software write
3173 	 * protection bits are volatile. The latter is indicated by
3174 	 * SNOR_F_SWP_IS_VOLATILE.
3175 	 */
3176 	if (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE) ||
3177 	    (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE) &&
3178 	     nor->flags & SNOR_F_SWP_IS_VOLATILE))
3179 		spi_nor_try_unlock_all(nor);
3180 
3181 	if (nor->addr_nbytes == 4 &&
3182 	    nor->read_proto != SNOR_PROTO_8_8_8_DTR &&
3183 	    !(nor->flags & SNOR_F_4B_OPCODES))
3184 		return spi_nor_set_4byte_addr_mode(nor, true);
3185 
3186 	return 0;
3187 }
3188 
3189 /**
3190  * spi_nor_soft_reset() - Perform a software reset
3191  * @nor:	pointer to 'struct spi_nor'
3192  *
3193  * Performs a "Soft Reset and Enter Default Protocol Mode" sequence which resets
3194  * the device to its power-on-reset state. This is useful when the software has
3195  * made some changes to device (volatile) registers and needs to reset it before
3196  * shutting down, for example.
3197  *
3198  * Not every flash supports this sequence. The same set of opcodes might be used
3199  * for some other operation on a flash that does not support this. Support for
3200  * this sequence can be discovered via SFDP in the BFPT table.
3201  *
3202  * Return: 0 on success, -errno otherwise.
3203  */
3204 static void spi_nor_soft_reset(struct spi_nor *nor)
3205 {
3206 	struct spi_mem_op op;
3207 	int ret;
3208 
3209 	op = (struct spi_mem_op)SPINOR_SRSTEN_OP;
3210 
3211 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3212 
3213 	ret = spi_mem_exec_op(nor->spimem, &op);
3214 	if (ret) {
3215 		if (ret != -EOPNOTSUPP)
3216 			dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3217 		return;
3218 	}
3219 
3220 	op = (struct spi_mem_op)SPINOR_SRST_OP;
3221 
3222 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3223 
3224 	ret = spi_mem_exec_op(nor->spimem, &op);
3225 	if (ret) {
3226 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3227 		return;
3228 	}
3229 
3230 	/*
3231 	 * Software Reset is not instant, and the delay varies from flash to
3232 	 * flash. Looking at a few flashes, most range somewhere below 100
3233 	 * microseconds. So, sleep for a range of 200-400 us.
3234 	 */
3235 	usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX);
3236 }
3237 
3238 /* mtd suspend handler */
3239 static int spi_nor_suspend(struct mtd_info *mtd)
3240 {
3241 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3242 	int ret;
3243 
3244 	/* Disable octal DTR mode if we enabled it. */
3245 	ret = spi_nor_set_octal_dtr(nor, false);
3246 	if (ret)
3247 		dev_err(nor->dev, "suspend() failed\n");
3248 
3249 	return ret;
3250 }
3251 
3252 /* mtd resume handler */
3253 static void spi_nor_resume(struct mtd_info *mtd)
3254 {
3255 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3256 	struct device *dev = nor->dev;
3257 	int ret;
3258 
3259 	/* re-initialize the nor chip */
3260 	ret = spi_nor_init(nor);
3261 	if (ret)
3262 		dev_err(dev, "resume() failed\n");
3263 }
3264 
3265 static int spi_nor_get_device(struct mtd_info *mtd)
3266 {
3267 	struct mtd_info *master = mtd_get_master(mtd);
3268 	struct spi_nor *nor = mtd_to_spi_nor(master);
3269 	struct device *dev;
3270 
3271 	if (nor->spimem)
3272 		dev = nor->spimem->spi->controller->dev.parent;
3273 	else
3274 		dev = nor->dev;
3275 
3276 	if (!try_module_get(dev->driver->owner))
3277 		return -ENODEV;
3278 
3279 	return 0;
3280 }
3281 
3282 static void spi_nor_put_device(struct mtd_info *mtd)
3283 {
3284 	struct mtd_info *master = mtd_get_master(mtd);
3285 	struct spi_nor *nor = mtd_to_spi_nor(master);
3286 	struct device *dev;
3287 
3288 	if (nor->spimem)
3289 		dev = nor->spimem->spi->controller->dev.parent;
3290 	else
3291 		dev = nor->dev;
3292 
3293 	module_put(dev->driver->owner);
3294 }
3295 
3296 static void spi_nor_restore(struct spi_nor *nor)
3297 {
3298 	int ret;
3299 
3300 	/* restore the addressing mode */
3301 	if (nor->addr_nbytes == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
3302 	    nor->flags & SNOR_F_BROKEN_RESET) {
3303 		ret = spi_nor_set_4byte_addr_mode(nor, false);
3304 		if (ret)
3305 			/*
3306 			 * Do not stop the execution in the hope that the flash
3307 			 * will default to the 3-byte address mode after the
3308 			 * software reset.
3309 			 */
3310 			dev_err(nor->dev, "Failed to exit 4-byte address mode, err = %d\n", ret);
3311 	}
3312 
3313 	if (nor->flags & SNOR_F_SOFT_RESET)
3314 		spi_nor_soft_reset(nor);
3315 }
3316 
3317 static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
3318 						   const char *name)
3319 {
3320 	unsigned int i, j;
3321 
3322 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
3323 		for (j = 0; j < manufacturers[i]->nparts; j++) {
3324 			if (!strcmp(name, manufacturers[i]->parts[j].name)) {
3325 				nor->manufacturer = manufacturers[i];
3326 				return &manufacturers[i]->parts[j];
3327 			}
3328 		}
3329 	}
3330 
3331 	return NULL;
3332 }
3333 
3334 static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
3335 						       const char *name)
3336 {
3337 	const struct flash_info *info = NULL;
3338 
3339 	if (name)
3340 		info = spi_nor_match_name(nor, name);
3341 	/* Try to auto-detect if chip name wasn't specified or not found */
3342 	if (!info)
3343 		return spi_nor_detect(nor);
3344 
3345 	/*
3346 	 * If caller has specified name of flash model that can normally be
3347 	 * detected using JEDEC, let's verify it.
3348 	 */
3349 	if (name && info->id) {
3350 		const struct flash_info *jinfo;
3351 
3352 		jinfo = spi_nor_detect(nor);
3353 		if (IS_ERR(jinfo)) {
3354 			return jinfo;
3355 		} else if (jinfo != info) {
3356 			/*
3357 			 * JEDEC knows better, so overwrite platform ID. We
3358 			 * can't trust partitions any longer, but we'll let
3359 			 * mtd apply them anyway, since some partitions may be
3360 			 * marked read-only, and we don't want to loose that
3361 			 * information, even if it's not 100% accurate.
3362 			 */
3363 			dev_warn(nor->dev, "found %s, expected %s\n",
3364 				 jinfo->name, info->name);
3365 			info = jinfo;
3366 		}
3367 	}
3368 
3369 	return info;
3370 }
3371 
3372 static u32
3373 spi_nor_get_region_erasesize(const struct spi_nor_erase_region *region,
3374 			     const struct spi_nor_erase_type *erase_type)
3375 {
3376 	int i;
3377 
3378 	if (region->overlaid)
3379 		return region->size;
3380 
3381 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
3382 		if (region->erase_mask & BIT(i))
3383 			return erase_type[i].size;
3384 	}
3385 
3386 	return 0;
3387 }
3388 
3389 static int spi_nor_set_mtd_eraseregions(struct spi_nor *nor)
3390 {
3391 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
3392 	const struct spi_nor_erase_region *region = map->regions;
3393 	struct mtd_erase_region_info *mtd_region;
3394 	struct mtd_info *mtd = &nor->mtd;
3395 	u32 erasesize, i;
3396 
3397 	mtd_region = devm_kcalloc(nor->dev, map->n_regions, sizeof(*mtd_region),
3398 				  GFP_KERNEL);
3399 	if (!mtd_region)
3400 		return -ENOMEM;
3401 
3402 	for (i = 0; i < map->n_regions; i++) {
3403 		erasesize = spi_nor_get_region_erasesize(&region[i],
3404 							 map->erase_type);
3405 		if (!erasesize)
3406 			return -EINVAL;
3407 
3408 		mtd_region[i].erasesize = erasesize;
3409 		mtd_region[i].numblocks = div64_ul(region[i].size, erasesize);
3410 		mtd_region[i].offset = region[i].offset;
3411 	}
3412 
3413 	mtd->numeraseregions = map->n_regions;
3414 	mtd->eraseregions = mtd_region;
3415 
3416 	return 0;
3417 }
3418 
3419 static int spi_nor_set_mtd_info(struct spi_nor *nor)
3420 {
3421 	struct mtd_info *mtd = &nor->mtd;
3422 	struct device *dev = nor->dev;
3423 
3424 	spi_nor_set_mtd_locking_ops(nor);
3425 	spi_nor_set_mtd_otp_ops(nor);
3426 
3427 	mtd->dev.parent = dev;
3428 	if (!mtd->name)
3429 		mtd->name = dev_name(dev);
3430 	mtd->type = MTD_NORFLASH;
3431 	mtd->flags = MTD_CAP_NORFLASH;
3432 	/* Unset BIT_WRITEABLE to enable JFFS2 write buffer for ECC'd NOR */
3433 	if (nor->flags & SNOR_F_ECC)
3434 		mtd->flags &= ~MTD_BIT_WRITEABLE;
3435 	if (nor->info->flags & SPI_NOR_NO_ERASE)
3436 		mtd->flags |= MTD_NO_ERASE;
3437 	else
3438 		mtd->_erase = spi_nor_erase;
3439 	mtd->writesize = nor->params->writesize;
3440 	mtd->writebufsize = nor->params->page_size;
3441 	mtd->size = nor->params->size;
3442 	mtd->_read = spi_nor_read;
3443 	/* Might be already set by some SST flashes. */
3444 	if (!mtd->_write)
3445 		mtd->_write = spi_nor_write;
3446 	mtd->_suspend = spi_nor_suspend;
3447 	mtd->_resume = spi_nor_resume;
3448 	mtd->_get_device = spi_nor_get_device;
3449 	mtd->_put_device = spi_nor_put_device;
3450 
3451 	if (!spi_nor_has_uniform_erase(nor))
3452 		return spi_nor_set_mtd_eraseregions(nor);
3453 
3454 	return 0;
3455 }
3456 
3457 static int spi_nor_hw_reset(struct spi_nor *nor)
3458 {
3459 	struct gpio_desc *reset;
3460 
3461 	reset = devm_gpiod_get_optional(nor->dev, "reset", GPIOD_OUT_LOW);
3462 	if (IS_ERR_OR_NULL(reset))
3463 		return PTR_ERR_OR_ZERO(reset);
3464 
3465 	/*
3466 	 * Experimental delay values by looking at different flash device
3467 	 * vendors datasheets.
3468 	 */
3469 	usleep_range(1, 5);
3470 	gpiod_set_value_cansleep(reset, 1);
3471 	usleep_range(100, 150);
3472 	gpiod_set_value_cansleep(reset, 0);
3473 	usleep_range(1000, 1200);
3474 
3475 	return 0;
3476 }
3477 
3478 int spi_nor_scan(struct spi_nor *nor, const char *name,
3479 		 const struct spi_nor_hwcaps *hwcaps)
3480 {
3481 	const struct flash_info *info;
3482 	struct device *dev = nor->dev;
3483 	int ret;
3484 
3485 	ret = spi_nor_check(nor);
3486 	if (ret)
3487 		return ret;
3488 
3489 	/* Reset SPI protocol for all commands. */
3490 	nor->reg_proto = SNOR_PROTO_1_1_1;
3491 	nor->read_proto = SNOR_PROTO_1_1_1;
3492 	nor->write_proto = SNOR_PROTO_1_1_1;
3493 
3494 	/*
3495 	 * We need the bounce buffer early to read/write registers when going
3496 	 * through the spi-mem layer (buffers have to be DMA-able).
3497 	 * For spi-mem drivers, we'll reallocate a new buffer if
3498 	 * nor->params->page_size turns out to be greater than PAGE_SIZE (which
3499 	 * shouldn't happen before long since NOR pages are usually less
3500 	 * than 1KB) after spi_nor_scan() returns.
3501 	 */
3502 	nor->bouncebuf_size = PAGE_SIZE;
3503 	nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3504 				      GFP_KERNEL);
3505 	if (!nor->bouncebuf)
3506 		return -ENOMEM;
3507 
3508 	ret = spi_nor_hw_reset(nor);
3509 	if (ret)
3510 		return ret;
3511 
3512 	info = spi_nor_get_flash_info(nor, name);
3513 	if (IS_ERR(info))
3514 		return PTR_ERR(info);
3515 
3516 	nor->info = info;
3517 
3518 	mutex_init(&nor->lock);
3519 
3520 	/* Init flash parameters based on flash_info struct and SFDP */
3521 	ret = spi_nor_init_params(nor);
3522 	if (ret)
3523 		return ret;
3524 
3525 	if (spi_nor_use_parallel_locking(nor))
3526 		init_waitqueue_head(&nor->rww.wait);
3527 
3528 	/*
3529 	 * Configure the SPI memory:
3530 	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
3531 	 * - set the number of dummy cycles (mode cycles + wait states).
3532 	 * - set the SPI protocols for register and memory accesses.
3533 	 * - set the number of address bytes.
3534 	 */
3535 	ret = spi_nor_setup(nor, hwcaps);
3536 	if (ret)
3537 		return ret;
3538 
3539 	/* Send all the required SPI flash commands to initialize device */
3540 	ret = spi_nor_init(nor);
3541 	if (ret)
3542 		return ret;
3543 
3544 	/* No mtd_info fields should be used up to this point. */
3545 	ret = spi_nor_set_mtd_info(nor);
3546 	if (ret)
3547 		return ret;
3548 
3549 	dev_dbg(dev, "Manufacturer and device ID: %*phN\n",
3550 		SPI_NOR_MAX_ID_LEN, nor->id);
3551 
3552 	return 0;
3553 }
3554 EXPORT_SYMBOL_GPL(spi_nor_scan);
3555 
3556 static int spi_nor_create_read_dirmap(struct spi_nor *nor)
3557 {
3558 	struct spi_mem_dirmap_info info = {
3559 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
3560 				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3561 				      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
3562 				      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
3563 		.offset = 0,
3564 		.length = nor->params->size,
3565 	};
3566 	struct spi_mem_op *op = &info.op_tmpl;
3567 
3568 	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
3569 
3570 	/* convert the dummy cycles to the number of bytes */
3571 	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
3572 	if (spi_nor_protocol_is_dtr(nor->read_proto))
3573 		op->dummy.nbytes *= 2;
3574 
3575 	/*
3576 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3577 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3578 	 * do it explicitly.
3579 	 */
3580 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
3581 
3582 	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3583 						       &info);
3584 	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
3585 }
3586 
3587 static int spi_nor_create_write_dirmap(struct spi_nor *nor)
3588 {
3589 	struct spi_mem_dirmap_info info = {
3590 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
3591 				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3592 				      SPI_MEM_OP_NO_DUMMY,
3593 				      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
3594 		.offset = 0,
3595 		.length = nor->params->size,
3596 	};
3597 	struct spi_mem_op *op = &info.op_tmpl;
3598 
3599 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
3600 		op->addr.nbytes = 0;
3601 
3602 	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
3603 
3604 	/*
3605 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3606 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3607 	 * do it explicitly.
3608 	 */
3609 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
3610 
3611 	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3612 						       &info);
3613 	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
3614 }
3615 
3616 static int spi_nor_probe(struct spi_mem *spimem)
3617 {
3618 	struct spi_device *spi = spimem->spi;
3619 	struct flash_platform_data *data = dev_get_platdata(&spi->dev);
3620 	struct spi_nor *nor;
3621 	/*
3622 	 * Enable all caps by default. The core will mask them after
3623 	 * checking what's really supported using spi_mem_supports_op().
3624 	 */
3625 	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };
3626 	char *flash_name;
3627 	int ret;
3628 
3629 	nor = devm_kzalloc(&spi->dev, sizeof(*nor), GFP_KERNEL);
3630 	if (!nor)
3631 		return -ENOMEM;
3632 
3633 	nor->spimem = spimem;
3634 	nor->dev = &spi->dev;
3635 	spi_nor_set_flash_node(nor, spi->dev.of_node);
3636 
3637 	spi_mem_set_drvdata(spimem, nor);
3638 
3639 	if (data && data->name)
3640 		nor->mtd.name = data->name;
3641 
3642 	if (!nor->mtd.name)
3643 		nor->mtd.name = spi_mem_get_name(spimem);
3644 
3645 	/*
3646 	 * For some (historical?) reason many platforms provide two different
3647 	 * names in flash_platform_data: "name" and "type". Quite often name is
3648 	 * set to "m25p80" and then "type" provides a real chip name.
3649 	 * If that's the case, respect "type" and ignore a "name".
3650 	 */
3651 	if (data && data->type)
3652 		flash_name = data->type;
3653 	else if (!strcmp(spi->modalias, "spi-nor"))
3654 		flash_name = NULL; /* auto-detect */
3655 	else
3656 		flash_name = spi->modalias;
3657 
3658 	ret = spi_nor_scan(nor, flash_name, &hwcaps);
3659 	if (ret)
3660 		return ret;
3661 
3662 	spi_nor_debugfs_register(nor);
3663 
3664 	/*
3665 	 * None of the existing parts have > 512B pages, but let's play safe
3666 	 * and add this logic so that if anyone ever adds support for such
3667 	 * a NOR we don't end up with buffer overflows.
3668 	 */
3669 	if (nor->params->page_size > PAGE_SIZE) {
3670 		nor->bouncebuf_size = nor->params->page_size;
3671 		devm_kfree(nor->dev, nor->bouncebuf);
3672 		nor->bouncebuf = devm_kmalloc(nor->dev,
3673 					      nor->bouncebuf_size,
3674 					      GFP_KERNEL);
3675 		if (!nor->bouncebuf)
3676 			return -ENOMEM;
3677 	}
3678 
3679 	ret = spi_nor_create_read_dirmap(nor);
3680 	if (ret)
3681 		return ret;
3682 
3683 	ret = spi_nor_create_write_dirmap(nor);
3684 	if (ret)
3685 		return ret;
3686 
3687 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
3688 				   data ? data->nr_parts : 0);
3689 }
3690 
3691 static int spi_nor_remove(struct spi_mem *spimem)
3692 {
3693 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3694 
3695 	spi_nor_restore(nor);
3696 
3697 	/* Clean up MTD stuff. */
3698 	return mtd_device_unregister(&nor->mtd);
3699 }
3700 
3701 static void spi_nor_shutdown(struct spi_mem *spimem)
3702 {
3703 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3704 
3705 	spi_nor_restore(nor);
3706 }
3707 
3708 /*
3709  * Do NOT add to this array without reading the following:
3710  *
3711  * Historically, many flash devices are bound to this driver by their name. But
3712  * since most of these flash are compatible to some extent, and their
3713  * differences can often be differentiated by the JEDEC read-ID command, we
3714  * encourage new users to add support to the spi-nor library, and simply bind
3715  * against a generic string here (e.g., "jedec,spi-nor").
3716  *
3717  * Many flash names are kept here in this list to keep them available
3718  * as module aliases for existing platforms.
3719  */
3720 static const struct spi_device_id spi_nor_dev_ids[] = {
3721 	/*
3722 	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
3723 	 * hack around the fact that the SPI core does not provide uevent
3724 	 * matching for .of_match_table
3725 	 */
3726 	{"spi-nor"},
3727 
3728 	/*
3729 	 * Entries not used in DTs that should be safe to drop after replacing
3730 	 * them with "spi-nor" in platform data.
3731 	 */
3732 	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"},
3733 
3734 	/*
3735 	 * Entries that were used in DTs without "jedec,spi-nor" fallback and
3736 	 * should be kept for backward compatibility.
3737 	 */
3738 	{"at25df321a"},	{"at25df641"},	{"at26df081a"},
3739 	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"},
3740 	{"mx25l25635e"},{"mx66l51235l"},
3741 	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"},
3742 	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"},
3743 	{"s25fl064k"},
3744 	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
3745 	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"},
3746 	{"m25p64"},	{"m25p128"},
3747 	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
3748 	{"w25q80bl"},	{"w25q128"},	{"w25q256"},
3749 
3750 	/* Flashes that can't be detected using JEDEC */
3751 	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
3752 	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
3753 	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
3754 
3755 	/* Everspin MRAMs (non-JEDEC) */
3756 	{ "mr25h128" }, /* 128 Kib, 40 MHz */
3757 	{ "mr25h256" }, /* 256 Kib, 40 MHz */
3758 	{ "mr25h10" },  /*   1 Mib, 40 MHz */
3759 	{ "mr25h40" },  /*   4 Mib, 40 MHz */
3760 
3761 	{ },
3762 };
3763 MODULE_DEVICE_TABLE(spi, spi_nor_dev_ids);
3764 
3765 static const struct of_device_id spi_nor_of_table[] = {
3766 	/*
3767 	 * Generic compatibility for SPI NOR that can be identified by the
3768 	 * JEDEC READ ID opcode (0x9F). Use this, if possible.
3769 	 */
3770 	{ .compatible = "jedec,spi-nor" },
3771 	{ /* sentinel */ },
3772 };
3773 MODULE_DEVICE_TABLE(of, spi_nor_of_table);
3774 
3775 /*
3776  * REVISIT: many of these chips have deep power-down modes, which
3777  * should clearly be entered on suspend() to minimize power use.
3778  * And also when they're otherwise idle...
3779  */
3780 static struct spi_mem_driver spi_nor_driver = {
3781 	.spidrv = {
3782 		.driver = {
3783 			.name = "spi-nor",
3784 			.of_match_table = spi_nor_of_table,
3785 			.dev_groups = spi_nor_sysfs_groups,
3786 		},
3787 		.id_table = spi_nor_dev_ids,
3788 	},
3789 	.probe = spi_nor_probe,
3790 	.remove = spi_nor_remove,
3791 	.shutdown = spi_nor_shutdown,
3792 };
3793 
3794 static int __init spi_nor_module_init(void)
3795 {
3796 	return spi_mem_driver_register(&spi_nor_driver);
3797 }
3798 module_init(spi_nor_module_init);
3799 
3800 static void __exit spi_nor_module_exit(void)
3801 {
3802 	spi_mem_driver_unregister(&spi_nor_driver);
3803 	spi_nor_debugfs_shutdown();
3804 }
3805 module_exit(spi_nor_module_exit);
3806 
3807 MODULE_LICENSE("GPL v2");
3808 MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
3809 MODULE_AUTHOR("Mike Lavender");
3810 MODULE_DESCRIPTION("framework for SPI NOR");
3811