xref: /rk3399_rockchip-uboot/drivers/mtd/spi/spi-nor-core.c (revision 3f2f32bfbcf44d2a46f9f8ac71d6311ae0459910)
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  * Synced from Linux v4.19
10  */
11 
12 #include <common.h>
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/log2.h>
16 #include <linux/math64.h>
17 #include <linux/sizes.h>
18 
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/spi-nor.h>
21 #include <spi-mem.h>
22 #include <spi.h>
23 
24 #include "sf_internal.h"
25 
26 /* Define max times to check status register before we give up. */
27 
28 /*
29  * For everything but full-chip erase; probably could be much smaller, but kept
30  * around for safety for now
31  */
32 
33 #define HZ					CONFIG_SYS_HZ
34 
35 #define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
36 
37 static int spi_nor_read_write_reg(struct spi_nor *nor, struct spi_mem_op
38 		*op, void *buf)
39 {
40 	if (op->data.dir == SPI_MEM_DATA_IN)
41 		op->data.buf.in = buf;
42 	else
43 		op->data.buf.out = buf;
44 	return spi_mem_exec_op(nor->spi, op);
45 }
46 
47 static int spi_nor_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len)
48 {
49 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(code, 1),
50 					  SPI_MEM_OP_NO_ADDR,
51 					  SPI_MEM_OP_NO_DUMMY,
52 					  SPI_MEM_OP_DATA_IN(len, NULL, 1));
53 	int ret;
54 
55 	ret = spi_nor_read_write_reg(nor, &op, val);
56 	if (ret < 0)
57 		dev_dbg(&flash->spimem->spi->dev, "error %d reading %x\n", ret,
58 			code);
59 
60 	return ret;
61 }
62 
63 static int spi_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
64 {
65 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 1),
66 					  SPI_MEM_OP_NO_ADDR,
67 					  SPI_MEM_OP_NO_DUMMY,
68 					  SPI_MEM_OP_DATA_OUT(len, NULL, 1));
69 
70 	return spi_nor_read_write_reg(nor, &op, buf);
71 }
72 
73 static ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len,
74 				 u_char *buf)
75 {
76 	struct spi_mem_op op =
77 			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
78 				   SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
79 				   SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
80 				   SPI_MEM_OP_DATA_IN(len, buf, 1));
81 	size_t remaining = len;
82 	int ret;
83 
84 	/* get transfer protocols. */
85 	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
86 	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
87 	op.dummy.buswidth = op.addr.buswidth;
88 	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
89 
90 	/* convert the dummy cycles to the number of bytes */
91 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
92 
93 	while (remaining) {
94 		op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
95 		ret = spi_mem_adjust_op_size(nor->spi, &op);
96 		if (ret)
97 			return ret;
98 
99 		ret = spi_mem_exec_op(nor->spi, &op);
100 		if (ret)
101 			return ret;
102 
103 		op.addr.val += op.data.nbytes;
104 		remaining -= op.data.nbytes;
105 		op.data.buf.in += op.data.nbytes;
106 	}
107 
108 	return len;
109 }
110 
111 static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
112 				  const u_char *buf)
113 {
114 	struct spi_mem_op op =
115 			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
116 				   SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
117 				   SPI_MEM_OP_NO_DUMMY,
118 				   SPI_MEM_OP_DATA_OUT(len, buf, 1));
119 	int ret;
120 
121 	/* get transfer protocols. */
122 	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
123 	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
124 	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
125 
126 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
127 		op.addr.nbytes = 0;
128 
129 	ret = spi_mem_adjust_op_size(nor->spi, &op);
130 	if (ret)
131 		return ret;
132 	op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes;
133 
134 	ret = spi_mem_exec_op(nor->spi, &op);
135 	if (ret)
136 		return ret;
137 
138 	return op.data.nbytes;
139 }
140 
141 /*
142  * Read the status register, returning its value in the location
143  * Return the status register value.
144  * Returns negative if error occurred.
145  */
146 static int read_sr(struct spi_nor *nor)
147 {
148 	int ret;
149 	u8 val;
150 
151 	ret = nor->read_reg(nor, SPINOR_OP_RDSR, &val, 1);
152 	if (ret < 0) {
153 		pr_debug("error %d reading SR\n", (int)ret);
154 		return ret;
155 	}
156 
157 	return val;
158 }
159 
160 /*
161  * Read the flag status register, returning its value in the location
162  * Return the status register value.
163  * Returns negative if error occurred.
164  */
165 static int read_fsr(struct spi_nor *nor)
166 {
167 	int ret;
168 	u8 val;
169 
170 	ret = nor->read_reg(nor, SPINOR_OP_RDFSR, &val, 1);
171 	if (ret < 0) {
172 		pr_debug("error %d reading FSR\n", ret);
173 		return ret;
174 	}
175 
176 	return val;
177 }
178 
179 /*
180  * Read configuration register, returning its value in the
181  * location. Return the configuration register value.
182  * Returns negative if error occurred.
183  */
184 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
185 static int read_cr(struct spi_nor *nor)
186 {
187 	int ret;
188 	u8 val;
189 
190 	ret = nor->read_reg(nor, SPINOR_OP_RDCR, &val, 1);
191 	if (ret < 0) {
192 		dev_dbg(nor->dev, "error %d reading CR\n", ret);
193 		return ret;
194 	}
195 
196 	return val;
197 }
198 #endif
199 
200 /*
201  * Write status register 1 byte
202  * Returns negative if error occurred.
203  */
204 static int write_sr(struct spi_nor *nor, u8 val)
205 {
206 	nor->cmd_buf[0] = val;
207 	return nor->write_reg(nor, SPINOR_OP_WRSR, nor->cmd_buf, 1);
208 }
209 
210 /*
211  * Set write enable latch with Write Enable command.
212  * Returns negative if error occurred.
213  */
214 static int write_enable(struct spi_nor *nor)
215 {
216 	return nor->write_reg(nor, SPINOR_OP_WREN, NULL, 0);
217 }
218 
219 /*
220  * Send write disable instruction to the chip.
221  */
222 static int write_disable(struct spi_nor *nor)
223 {
224 	return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0);
225 }
226 
227 static struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
228 {
229 	return mtd->priv;
230 }
231 
232 #ifndef CONFIG_SPI_FLASH_BAR
233 static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
234 {
235 	size_t i;
236 
237 	for (i = 0; i < size; i++)
238 		if (table[i][0] == opcode)
239 			return table[i][1];
240 
241 	/* No conversion found, keep input op code. */
242 	return opcode;
243 }
244 
245 static u8 spi_nor_convert_3to4_read(u8 opcode)
246 {
247 	static const u8 spi_nor_3to4_read[][2] = {
248 		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
249 		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
250 		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
251 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
252 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
253 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
254 
255 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
256 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
257 		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
258 	};
259 
260 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
261 				      ARRAY_SIZE(spi_nor_3to4_read));
262 }
263 
264 static u8 spi_nor_convert_3to4_program(u8 opcode)
265 {
266 	static const u8 spi_nor_3to4_program[][2] = {
267 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
268 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
269 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
270 	};
271 
272 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
273 				      ARRAY_SIZE(spi_nor_3to4_program));
274 }
275 
276 static u8 spi_nor_convert_3to4_erase(u8 opcode)
277 {
278 	static const u8 spi_nor_3to4_erase[][2] = {
279 		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
280 		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
281 		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
282 	};
283 
284 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
285 				      ARRAY_SIZE(spi_nor_3to4_erase));
286 }
287 
288 static void spi_nor_set_4byte_opcodes(struct spi_nor *nor,
289 				      const struct flash_info *info)
290 {
291 	/* Do some manufacturer fixups first */
292 	switch (JEDEC_MFR(info)) {
293 	case SNOR_MFR_SPANSION:
294 		/* No small sector erase for 4-byte command set */
295 		nor->erase_opcode = SPINOR_OP_SE;
296 		nor->mtd.erasesize = info->sector_size;
297 		break;
298 
299 	default:
300 		break;
301 	}
302 
303 	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
304 	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
305 	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
306 }
307 #endif /* !CONFIG_SPI_FLASH_BAR */
308 
309 /* Enable/disable 4-byte addressing mode. */
310 static int set_4byte(struct spi_nor *nor, const struct flash_info *info,
311 		     int enable)
312 {
313 	int status;
314 	bool need_wren = false;
315 	u8 cmd;
316 
317 	switch (JEDEC_MFR(info)) {
318 	case SNOR_MFR_ST:
319 	case SNOR_MFR_MICRON:
320 		/* Some Micron need WREN command; all will accept it */
321 		need_wren = true;
322 	case SNOR_MFR_MACRONIX:
323 	case SNOR_MFR_WINBOND:
324 		if (need_wren)
325 			write_enable(nor);
326 
327 		cmd = enable ? SPINOR_OP_EN4B : SPINOR_OP_EX4B;
328 		status = nor->write_reg(nor, cmd, NULL, 0);
329 		if (need_wren)
330 			write_disable(nor);
331 
332 		if (!status && !enable &&
333 		    JEDEC_MFR(info) == SNOR_MFR_WINBOND) {
334 			/*
335 			 * On Winbond W25Q256FV, leaving 4byte mode causes
336 			 * the Extended Address Register to be set to 1, so all
337 			 * 3-byte-address reads come from the second 16M.
338 			 * We must clear the register to enable normal behavior.
339 			 */
340 			write_enable(nor);
341 			nor->cmd_buf[0] = 0;
342 			nor->write_reg(nor, SPINOR_OP_WREAR, nor->cmd_buf, 1);
343 			write_disable(nor);
344 		}
345 
346 		return status;
347 	default:
348 		/* Spansion style */
349 		nor->cmd_buf[0] = enable << 7;
350 		return nor->write_reg(nor, SPINOR_OP_BRWR, nor->cmd_buf, 1);
351 	}
352 }
353 
354 static int spi_nor_sr_ready(struct spi_nor *nor)
355 {
356 	int sr = read_sr(nor);
357 
358 	if (sr < 0)
359 		return sr;
360 
361 	if (nor->flags & SNOR_F_USE_CLSR && sr & (SR_E_ERR | SR_P_ERR)) {
362 		if (sr & SR_E_ERR)
363 			dev_dbg(nor->dev, "Erase Error occurred\n");
364 		else
365 			dev_dbg(nor->dev, "Programming Error occurred\n");
366 
367 		nor->write_reg(nor, SPINOR_OP_CLSR, NULL, 0);
368 		return -EIO;
369 	}
370 
371 	return !(sr & SR_WIP);
372 }
373 
374 static int spi_nor_fsr_ready(struct spi_nor *nor)
375 {
376 	int fsr = read_fsr(nor);
377 
378 	if (fsr < 0)
379 		return fsr;
380 
381 	if (fsr & (FSR_E_ERR | FSR_P_ERR)) {
382 		if (fsr & FSR_E_ERR)
383 			dev_err(nor->dev, "Erase operation failed.\n");
384 		else
385 			dev_err(nor->dev, "Program operation failed.\n");
386 
387 		if (fsr & FSR_PT_ERR)
388 			dev_err(nor->dev,
389 				"Attempted to modify a protected sector.\n");
390 
391 		nor->write_reg(nor, SPINOR_OP_CLFSR, NULL, 0);
392 		return -EIO;
393 	}
394 
395 	return fsr & FSR_READY;
396 }
397 
398 static int spi_nor_ready(struct spi_nor *nor)
399 {
400 	int sr, fsr;
401 
402 	sr = spi_nor_sr_ready(nor);
403 	if (sr < 0)
404 		return sr;
405 	fsr = nor->flags & SNOR_F_USE_FSR ? spi_nor_fsr_ready(nor) : 1;
406 	if (fsr < 0)
407 		return fsr;
408 	return sr && fsr;
409 }
410 
411 /*
412  * Service routine to read status register until ready, or timeout occurs.
413  * Returns non-zero if error.
414  */
415 static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
416 						unsigned long timeout)
417 {
418 	unsigned long timebase;
419 	int ret;
420 
421 	timebase = get_timer(0);
422 
423 	while (get_timer(timebase) < timeout) {
424 		ret = spi_nor_ready(nor);
425 		if (ret < 0)
426 			return ret;
427 		if (ret)
428 			return 0;
429 	}
430 
431 	dev_err(nor->dev, "flash operation timed out\n");
432 
433 	return -ETIMEDOUT;
434 }
435 
436 static int spi_nor_wait_till_ready(struct spi_nor *nor)
437 {
438 	return spi_nor_wait_till_ready_with_timeout(nor,
439 						    DEFAULT_READY_WAIT_JIFFIES);
440 }
441 
442 #ifdef CONFIG_SPI_FLASH_BAR
443 /*
444  * This "clean_bar" is necessary in a situation when one was accessing
445  * spi flash memory > 16 MiB by using Bank Address Register's BA24 bit.
446  *
447  * After it the BA24 bit shall be cleared to allow access to correct
448  * memory region after SW reset (by calling "reset" command).
449  *
450  * Otherwise, the BA24 bit may be left set and then after reset, the
451  * ROM would read/write/erase SPL from 16 MiB * bank_sel address.
452  */
453 static int clean_bar(struct spi_nor *nor)
454 {
455 	u8 cmd, bank_sel = 0;
456 
457 	if (nor->bank_curr == 0)
458 		return 0;
459 	cmd = nor->bank_write_cmd;
460 	nor->bank_curr = 0;
461 	write_enable(nor);
462 
463 	return nor->write_reg(nor, cmd, &bank_sel, 1);
464 }
465 
466 static int write_bar(struct spi_nor *nor, u32 offset)
467 {
468 	u8 cmd, bank_sel;
469 	int ret;
470 
471 	bank_sel = offset / SZ_16M;
472 	if (bank_sel == nor->bank_curr)
473 		goto bar_end;
474 
475 	cmd = nor->bank_write_cmd;
476 	write_enable(nor);
477 	ret = nor->write_reg(nor, cmd, &bank_sel, 1);
478 	if (ret < 0) {
479 		debug("SF: fail to write bank register\n");
480 		return ret;
481 	}
482 
483 bar_end:
484 	nor->bank_curr = bank_sel;
485 	return nor->bank_curr;
486 }
487 
488 static int read_bar(struct spi_nor *nor, const struct flash_info *info)
489 {
490 	u8 curr_bank = 0;
491 	int ret;
492 
493 	switch (JEDEC_MFR(info)) {
494 	case SNOR_MFR_SPANSION:
495 		nor->bank_read_cmd = SPINOR_OP_BRRD;
496 		nor->bank_write_cmd = SPINOR_OP_BRWR;
497 		break;
498 	default:
499 		nor->bank_read_cmd = SPINOR_OP_RDEAR;
500 		nor->bank_write_cmd = SPINOR_OP_WREAR;
501 	}
502 
503 	ret = nor->read_reg(nor, nor->bank_read_cmd,
504 				    &curr_bank, 1);
505 	if (ret) {
506 		debug("SF: fail to read bank addr register\n");
507 		return ret;
508 	}
509 	nor->bank_curr = curr_bank;
510 
511 	return 0;
512 }
513 #endif
514 
515 /*
516  * Initiate the erasure of a single sector
517  */
518 static int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
519 {
520 	struct spi_mem_op op =
521 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->erase_opcode, 1),
522 			   SPI_MEM_OP_ADDR(nor->addr_width, addr, 1),
523 			   SPI_MEM_OP_NO_DUMMY,
524 			   SPI_MEM_OP_NO_DATA);
525 
526 	if (nor->erase)
527 		return nor->erase(nor, addr);
528 
529 	/*
530 	 * Default implementation, if driver doesn't have a specialized HW
531 	 * control
532 	 */
533 	return spi_mem_exec_op(nor->spi, &op);
534 }
535 
536 /*
537  * Erase an address range on the nor chip.  The address range may extend
538  * one or more erase sectors.  Return an error is there is a problem erasing.
539  */
540 static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
541 {
542 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
543 	u32 addr, len, rem;
544 	int ret;
545 
546 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
547 		(long long)instr->len);
548 
549 	div_u64_rem(instr->len, mtd->erasesize, &rem);
550 	if (rem)
551 		return -EINVAL;
552 
553 	addr = instr->addr;
554 	len = instr->len;
555 
556 	while (len) {
557 #ifdef CONFIG_SPI_FLASH_BAR
558 		ret = write_bar(nor, addr);
559 		if (ret < 0)
560 			return ret;
561 #endif
562 		write_enable(nor);
563 
564 		ret = spi_nor_erase_sector(nor, addr);
565 		if (ret)
566 			goto erase_err;
567 
568 		addr += mtd->erasesize;
569 		len -= mtd->erasesize;
570 
571 		ret = spi_nor_wait_till_ready(nor);
572 		if (ret)
573 			goto erase_err;
574 	}
575 
576 erase_err:
577 #ifdef CONFIG_SPI_FLASH_BAR
578 	ret = clean_bar(nor);
579 #endif
580 	write_disable(nor);
581 
582 	return ret;
583 }
584 
585 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
586 /* Write status register and ensure bits in mask match written values */
587 static int write_sr_and_check(struct spi_nor *nor, u8 status_new, u8 mask)
588 {
589 	int ret;
590 
591 	write_enable(nor);
592 	ret = write_sr(nor, status_new);
593 	if (ret)
594 		return ret;
595 
596 	ret = spi_nor_wait_till_ready(nor);
597 	if (ret)
598 		return ret;
599 
600 	ret = read_sr(nor);
601 	if (ret < 0)
602 		return ret;
603 
604 	return ((ret & mask) != (status_new & mask)) ? -EIO : 0;
605 }
606 
607 static void stm_get_locked_range(struct spi_nor *nor, u8 sr, loff_t *ofs,
608 				 uint64_t *len)
609 {
610 	struct mtd_info *mtd = &nor->mtd;
611 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
612 	int shift = ffs(mask) - 1;
613 	int pow;
614 
615 	if (!(sr & mask)) {
616 		/* No protection */
617 		*ofs = 0;
618 		*len = 0;
619 	} else {
620 		pow = ((sr & mask) ^ mask) >> shift;
621 		*len = mtd->size >> pow;
622 		if (nor->flags & SNOR_F_HAS_SR_TB && sr & SR_TB)
623 			*ofs = 0;
624 		else
625 			*ofs = mtd->size - *len;
626 	}
627 }
628 
629 /*
630  * Return 1 if the entire region is locked (if @locked is true) or unlocked (if
631  * @locked is false); 0 otherwise
632  */
633 static int stm_check_lock_status_sr(struct spi_nor *nor, loff_t ofs, u64 len,
634 				    u8 sr, bool locked)
635 {
636 	loff_t lock_offs;
637 	uint64_t lock_len;
638 
639 	if (!len)
640 		return 1;
641 
642 	stm_get_locked_range(nor, sr, &lock_offs, &lock_len);
643 
644 	if (locked)
645 		/* Requested range is a sub-range of locked range */
646 		return (ofs + len <= lock_offs + lock_len) && (ofs >= lock_offs);
647 	else
648 		/* Requested range does not overlap with locked range */
649 		return (ofs >= lock_offs + lock_len) || (ofs + len <= lock_offs);
650 }
651 
652 static int stm_is_locked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
653 			    u8 sr)
654 {
655 	return stm_check_lock_status_sr(nor, ofs, len, sr, true);
656 }
657 
658 static int stm_is_unlocked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
659 			      u8 sr)
660 {
661 	return stm_check_lock_status_sr(nor, ofs, len, sr, false);
662 }
663 
664 /*
665  * Lock a region of the flash. Compatible with ST Micro and similar flash.
666  * Supports the block protection bits BP{0,1,2} in the status register
667  * (SR). Does not support these features found in newer SR bitfields:
668  *   - SEC: sector/block protect - only handle SEC=0 (block protect)
669  *   - CMP: complement protect - only support CMP=0 (range is not complemented)
670  *
671  * Support for the following is provided conditionally for some flash:
672  *   - TB: top/bottom protect
673  *
674  * Sample table portion for 8MB flash (Winbond w25q64fw):
675  *
676  *   SEC  |  TB   |  BP2  |  BP1  |  BP0  |  Prot Length  | Protected Portion
677  *  --------------------------------------------------------------------------
678  *    X   |   X   |   0   |   0   |   0   |  NONE         | NONE
679  *    0   |   0   |   0   |   0   |   1   |  128 KB       | Upper 1/64
680  *    0   |   0   |   0   |   1   |   0   |  256 KB       | Upper 1/32
681  *    0   |   0   |   0   |   1   |   1   |  512 KB       | Upper 1/16
682  *    0   |   0   |   1   |   0   |   0   |  1 MB         | Upper 1/8
683  *    0   |   0   |   1   |   0   |   1   |  2 MB         | Upper 1/4
684  *    0   |   0   |   1   |   1   |   0   |  4 MB         | Upper 1/2
685  *    X   |   X   |   1   |   1   |   1   |  8 MB         | ALL
686  *  ------|-------|-------|-------|-------|---------------|-------------------
687  *    0   |   1   |   0   |   0   |   1   |  128 KB       | Lower 1/64
688  *    0   |   1   |   0   |   1   |   0   |  256 KB       | Lower 1/32
689  *    0   |   1   |   0   |   1   |   1   |  512 KB       | Lower 1/16
690  *    0   |   1   |   1   |   0   |   0   |  1 MB         | Lower 1/8
691  *    0   |   1   |   1   |   0   |   1   |  2 MB         | Lower 1/4
692  *    0   |   1   |   1   |   1   |   0   |  4 MB         | Lower 1/2
693  *
694  * Returns negative on errors, 0 on success.
695  */
696 static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
697 {
698 	struct mtd_info *mtd = &nor->mtd;
699 	int status_old, status_new;
700 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
701 	u8 shift = ffs(mask) - 1, pow, val;
702 	loff_t lock_len;
703 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
704 	bool use_top;
705 
706 	status_old = read_sr(nor);
707 	if (status_old < 0)
708 		return status_old;
709 
710 	/* If nothing in our range is unlocked, we don't need to do anything */
711 	if (stm_is_locked_sr(nor, ofs, len, status_old))
712 		return 0;
713 
714 	/* If anything below us is unlocked, we can't use 'bottom' protection */
715 	if (!stm_is_locked_sr(nor, 0, ofs, status_old))
716 		can_be_bottom = false;
717 
718 	/* If anything above us is unlocked, we can't use 'top' protection */
719 	if (!stm_is_locked_sr(nor, ofs + len, mtd->size - (ofs + len),
720 			      status_old))
721 		can_be_top = false;
722 
723 	if (!can_be_bottom && !can_be_top)
724 		return -EINVAL;
725 
726 	/* Prefer top, if both are valid */
727 	use_top = can_be_top;
728 
729 	/* lock_len: length of region that should end up locked */
730 	if (use_top)
731 		lock_len = mtd->size - ofs;
732 	else
733 		lock_len = ofs + len;
734 
735 	/*
736 	 * Need smallest pow such that:
737 	 *
738 	 *   1 / (2^pow) <= (len / size)
739 	 *
740 	 * so (assuming power-of-2 size) we do:
741 	 *
742 	 *   pow = ceil(log2(size / len)) = log2(size) - floor(log2(len))
743 	 */
744 	pow = ilog2(mtd->size) - ilog2(lock_len);
745 	val = mask - (pow << shift);
746 	if (val & ~mask)
747 		return -EINVAL;
748 	/* Don't "lock" with no region! */
749 	if (!(val & mask))
750 		return -EINVAL;
751 
752 	status_new = (status_old & ~mask & ~SR_TB) | val;
753 
754 	/* Disallow further writes if WP pin is asserted */
755 	status_new |= SR_SRWD;
756 
757 	if (!use_top)
758 		status_new |= SR_TB;
759 
760 	/* Don't bother if they're the same */
761 	if (status_new == status_old)
762 		return 0;
763 
764 	/* Only modify protection if it will not unlock other areas */
765 	if ((status_new & mask) < (status_old & mask))
766 		return -EINVAL;
767 
768 	return write_sr_and_check(nor, status_new, mask);
769 }
770 
771 /*
772  * Unlock a region of the flash. See stm_lock() for more info
773  *
774  * Returns negative on errors, 0 on success.
775  */
776 static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
777 {
778 	struct mtd_info *mtd = &nor->mtd;
779 	int status_old, status_new;
780 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
781 	u8 shift = ffs(mask) - 1, pow, val;
782 	loff_t lock_len;
783 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
784 	bool use_top;
785 
786 	status_old = read_sr(nor);
787 	if (status_old < 0)
788 		return status_old;
789 
790 	/* If nothing in our range is locked, we don't need to do anything */
791 	if (stm_is_unlocked_sr(nor, ofs, len, status_old))
792 		return 0;
793 
794 	/* If anything below us is locked, we can't use 'top' protection */
795 	if (!stm_is_unlocked_sr(nor, 0, ofs, status_old))
796 		can_be_top = false;
797 
798 	/* If anything above us is locked, we can't use 'bottom' protection */
799 	if (!stm_is_unlocked_sr(nor, ofs + len, mtd->size - (ofs + len),
800 				status_old))
801 		can_be_bottom = false;
802 
803 	if (!can_be_bottom && !can_be_top)
804 		return -EINVAL;
805 
806 	/* Prefer top, if both are valid */
807 	use_top = can_be_top;
808 
809 	/* lock_len: length of region that should remain locked */
810 	if (use_top)
811 		lock_len = mtd->size - (ofs + len);
812 	else
813 		lock_len = ofs;
814 
815 	/*
816 	 * Need largest pow such that:
817 	 *
818 	 *   1 / (2^pow) >= (len / size)
819 	 *
820 	 * so (assuming power-of-2 size) we do:
821 	 *
822 	 *   pow = floor(log2(size / len)) = log2(size) - ceil(log2(len))
823 	 */
824 	pow = ilog2(mtd->size) - order_base_2(lock_len);
825 	if (lock_len == 0) {
826 		val = 0; /* fully unlocked */
827 	} else {
828 		val = mask - (pow << shift);
829 		/* Some power-of-two sizes are not supported */
830 		if (val & ~mask)
831 			return -EINVAL;
832 	}
833 
834 	status_new = (status_old & ~mask & ~SR_TB) | val;
835 
836 	/* Don't protect status register if we're fully unlocked */
837 	if (lock_len == 0)
838 		status_new &= ~SR_SRWD;
839 
840 	if (!use_top)
841 		status_new |= SR_TB;
842 
843 	/* Don't bother if they're the same */
844 	if (status_new == status_old)
845 		return 0;
846 
847 	/* Only modify protection if it will not lock other areas */
848 	if ((status_new & mask) > (status_old & mask))
849 		return -EINVAL;
850 
851 	return write_sr_and_check(nor, status_new, mask);
852 }
853 
854 /*
855  * Check if a region of the flash is (completely) locked. See stm_lock() for
856  * more info.
857  *
858  * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
859  * negative on errors.
860  */
861 static int stm_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
862 {
863 	int status;
864 
865 	status = read_sr(nor);
866 	if (status < 0)
867 		return status;
868 
869 	return stm_is_locked_sr(nor, ofs, len, status);
870 }
871 #endif /* CONFIG_SPI_FLASH_STMICRO */
872 
873 static const struct flash_info *spi_nor_read_id(struct spi_nor *nor)
874 {
875 	int			tmp;
876 	u8			id[SPI_NOR_MAX_ID_LEN];
877 	const struct flash_info	*info;
878 
879 	tmp = nor->read_reg(nor, SPINOR_OP_RDID, id, SPI_NOR_MAX_ID_LEN);
880 	if (tmp < 0) {
881 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", tmp);
882 		return ERR_PTR(tmp);
883 	}
884 
885 	info = spi_nor_ids;
886 	for (; info->name; info++) {
887 		if (info->id_len) {
888 			if (!memcmp(info->id, id, info->id_len))
889 				return info;
890 		}
891 	}
892 
893 	dev_err(nor->dev, "unrecognized JEDEC id bytes: %02x, %02x, %02x\n",
894 		id[0], id[1], id[2]);
895 	return ERR_PTR(-ENODEV);
896 }
897 
898 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
899 			size_t *retlen, u_char *buf)
900 {
901 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
902 	int ret;
903 
904 	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
905 
906 	while (len) {
907 		loff_t addr = from;
908 		size_t read_len = len;
909 
910 #ifdef CONFIG_SPI_FLASH_BAR
911 		u32 remain_len;
912 
913 		ret = write_bar(nor, addr);
914 		if (ret < 0)
915 			return log_ret(ret);
916 		remain_len = (SZ_16M * (nor->bank_curr + 1)) - addr;
917 
918 		if (len < remain_len)
919 			read_len = len;
920 		else
921 			read_len = remain_len;
922 #endif
923 
924 		ret = nor->read(nor, addr, read_len, buf);
925 		if (ret == 0) {
926 			/* We shouldn't see 0-length reads */
927 			ret = -EIO;
928 			goto read_err;
929 		}
930 		if (ret < 0)
931 			goto read_err;
932 
933 		*retlen += ret;
934 		buf += ret;
935 		from += ret;
936 		len -= ret;
937 	}
938 	ret = 0;
939 
940 read_err:
941 #ifdef CONFIG_SPI_FLASH_BAR
942 	ret = clean_bar(nor);
943 #endif
944 	return ret;
945 }
946 
947 #ifdef CONFIG_SPI_FLASH_SST
948 /*
949  * sst26 flash series has its own block protection implementation:
950  * 4x   - 8  KByte blocks - read & write protection bits - upper addresses
951  * 1x   - 32 KByte blocks - write protection bits
952  * rest - 64 KByte blocks - write protection bits
953  * 1x   - 32 KByte blocks - write protection bits
954  * 4x   - 8  KByte blocks - read & write protection bits - lower addresses
955  *
956  * We'll support only per 64k lock/unlock so lower and upper 64 KByte region
957  * will be treated as single block.
958  */
959 #define SST26_BPR_8K_NUM		4
960 #define SST26_MAX_BPR_REG_LEN		(18 + 1)
961 #define SST26_BOUND_REG_SIZE		((32 + SST26_BPR_8K_NUM * 8) * SZ_1K)
962 
963 enum lock_ctl {
964 	SST26_CTL_LOCK,
965 	SST26_CTL_UNLOCK,
966 	SST26_CTL_CHECK
967 };
968 
969 static bool sst26_process_bpr(u32 bpr_size, u8 *cmd, u32 bit, enum lock_ctl ctl)
970 {
971 	switch (ctl) {
972 	case SST26_CTL_LOCK:
973 		cmd[bpr_size - (bit / 8) - 1] |= BIT(bit % 8);
974 		break;
975 	case SST26_CTL_UNLOCK:
976 		cmd[bpr_size - (bit / 8) - 1] &= ~BIT(bit % 8);
977 		break;
978 	case SST26_CTL_CHECK:
979 		return !!(cmd[bpr_size - (bit / 8) - 1] & BIT(bit % 8));
980 	}
981 
982 	return false;
983 }
984 
985 /*
986  * Lock, unlock or check lock status of the flash region of the flash (depending
987  * on the lock_ctl value)
988  */
989 static int sst26_lock_ctl(struct spi_nor *nor, loff_t ofs, uint64_t len, enum lock_ctl ctl)
990 {
991 	struct mtd_info *mtd = &nor->mtd;
992 	u32 i, bpr_ptr, rptr_64k, lptr_64k, bpr_size;
993 	bool lower_64k = false, upper_64k = false;
994 	u8 bpr_buff[SST26_MAX_BPR_REG_LEN] = {};
995 	int ret;
996 
997 	/* Check length and offset for 64k alignment */
998 	if ((ofs & (SZ_64K - 1)) || (len & (SZ_64K - 1))) {
999 		dev_err(nor->dev, "length or offset is not 64KiB allighned\n");
1000 		return -EINVAL;
1001 	}
1002 
1003 	if (ofs + len > mtd->size) {
1004 		dev_err(nor->dev, "range is more than device size: %#llx + %#llx > %#llx\n",
1005 			ofs, len, mtd->size);
1006 		return -EINVAL;
1007 	}
1008 
1009 	/* SST26 family has only 16 Mbit, 32 Mbit and 64 Mbit IC */
1010 	if (mtd->size != SZ_2M &&
1011 	    mtd->size != SZ_4M &&
1012 	    mtd->size != SZ_8M)
1013 		return -EINVAL;
1014 
1015 	bpr_size = 2 + (mtd->size / SZ_64K / 8);
1016 
1017 	ret = nor->read_reg(nor, SPINOR_OP_READ_BPR, bpr_buff, bpr_size);
1018 	if (ret < 0) {
1019 		dev_err(nor->dev, "fail to read block-protection register\n");
1020 		return ret;
1021 	}
1022 
1023 	rptr_64k = min_t(u32, ofs + len, mtd->size - SST26_BOUND_REG_SIZE);
1024 	lptr_64k = max_t(u32, ofs, SST26_BOUND_REG_SIZE);
1025 
1026 	upper_64k = ((ofs + len) > (mtd->size - SST26_BOUND_REG_SIZE));
1027 	lower_64k = (ofs < SST26_BOUND_REG_SIZE);
1028 
1029 	/* Lower bits in block-protection register are about 64k region */
1030 	bpr_ptr = lptr_64k / SZ_64K - 1;
1031 
1032 	/* Process 64K blocks region */
1033 	while (lptr_64k < rptr_64k) {
1034 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
1035 			return EACCES;
1036 
1037 		bpr_ptr++;
1038 		lptr_64k += SZ_64K;
1039 	}
1040 
1041 	/* 32K and 8K region bits in BPR are after 64k region bits */
1042 	bpr_ptr = (mtd->size - 2 * SST26_BOUND_REG_SIZE) / SZ_64K;
1043 
1044 	/* Process lower 32K block region */
1045 	if (lower_64k)
1046 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
1047 			return EACCES;
1048 
1049 	bpr_ptr++;
1050 
1051 	/* Process upper 32K block region */
1052 	if (upper_64k)
1053 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
1054 			return EACCES;
1055 
1056 	bpr_ptr++;
1057 
1058 	/* Process lower 8K block regions */
1059 	for (i = 0; i < SST26_BPR_8K_NUM; i++) {
1060 		if (lower_64k)
1061 			if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
1062 				return EACCES;
1063 
1064 		/* In 8K area BPR has both read and write protection bits */
1065 		bpr_ptr += 2;
1066 	}
1067 
1068 	/* Process upper 8K block regions */
1069 	for (i = 0; i < SST26_BPR_8K_NUM; i++) {
1070 		if (upper_64k)
1071 			if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
1072 				return EACCES;
1073 
1074 		/* In 8K area BPR has both read and write protection bits */
1075 		bpr_ptr += 2;
1076 	}
1077 
1078 	/* If we check region status we don't need to write BPR back */
1079 	if (ctl == SST26_CTL_CHECK)
1080 		return 0;
1081 
1082 	ret = nor->write_reg(nor, SPINOR_OP_WRITE_BPR, bpr_buff, bpr_size);
1083 	if (ret < 0) {
1084 		dev_err(nor->dev, "fail to write block-protection register\n");
1085 		return ret;
1086 	}
1087 
1088 	return 0;
1089 }
1090 
1091 static int sst26_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
1092 {
1093 	return sst26_lock_ctl(nor, ofs, len, SST26_CTL_UNLOCK);
1094 }
1095 
1096 static int sst26_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
1097 {
1098 	return sst26_lock_ctl(nor, ofs, len, SST26_CTL_LOCK);
1099 }
1100 
1101 /*
1102  * Returns EACCES (positive value) if region is locked, 0 if region is unlocked,
1103  * and negative on errors.
1104  */
1105 static int sst26_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
1106 {
1107 	/*
1108 	 * is_locked function is used for check before reading or erasing flash
1109 	 * region, so offset and length might be not 64k allighned, so adjust
1110 	 * them to be 64k allighned as sst26_lock_ctl works only with 64k
1111 	 * allighned regions.
1112 	 */
1113 	ofs -= ofs & (SZ_64K - 1);
1114 	len = len & (SZ_64K - 1) ? (len & ~(SZ_64K - 1)) + SZ_64K : len;
1115 
1116 	return sst26_lock_ctl(nor, ofs, len, SST26_CTL_CHECK);
1117 }
1118 
1119 static int sst_write_byteprogram(struct spi_nor *nor, loff_t to, size_t len,
1120 				 size_t *retlen, const u_char *buf)
1121 {
1122 	size_t actual;
1123 	int ret = 0;
1124 
1125 	for (actual = 0; actual < len; actual++) {
1126 		nor->program_opcode = SPINOR_OP_BP;
1127 
1128 		write_enable(nor);
1129 		/* write one byte. */
1130 		ret = nor->write(nor, to, 1, buf + actual);
1131 		if (ret < 0)
1132 			goto sst_write_err;
1133 		ret = spi_nor_wait_till_ready(nor);
1134 		if (ret)
1135 			goto sst_write_err;
1136 		to++;
1137 	}
1138 
1139 sst_write_err:
1140 	write_disable(nor);
1141 	return ret;
1142 }
1143 
1144 static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
1145 		     size_t *retlen, const u_char *buf)
1146 {
1147 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1148 	struct spi_slave *spi = nor->spi;
1149 	size_t actual;
1150 	int ret;
1151 
1152 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
1153 	if (spi->mode & SPI_TX_BYTE)
1154 		return sst_write_byteprogram(nor, to, len, retlen, buf);
1155 
1156 	write_enable(nor);
1157 
1158 	nor->sst_write_second = false;
1159 
1160 	actual = to % 2;
1161 	/* Start write from odd address. */
1162 	if (actual) {
1163 		nor->program_opcode = SPINOR_OP_BP;
1164 
1165 		/* write one byte. */
1166 		ret = nor->write(nor, to, 1, buf);
1167 		if (ret < 0)
1168 			goto sst_write_err;
1169 		ret = spi_nor_wait_till_ready(nor);
1170 		if (ret)
1171 			goto sst_write_err;
1172 	}
1173 	to += actual;
1174 
1175 	/* Write out most of the data here. */
1176 	for (; actual < len - 1; actual += 2) {
1177 		nor->program_opcode = SPINOR_OP_AAI_WP;
1178 
1179 		/* write two bytes. */
1180 		ret = nor->write(nor, to, 2, buf + actual);
1181 		if (ret < 0)
1182 			goto sst_write_err;
1183 		ret = spi_nor_wait_till_ready(nor);
1184 		if (ret)
1185 			goto sst_write_err;
1186 		to += 2;
1187 		nor->sst_write_second = true;
1188 	}
1189 	nor->sst_write_second = false;
1190 
1191 	write_disable(nor);
1192 	ret = spi_nor_wait_till_ready(nor);
1193 	if (ret)
1194 		goto sst_write_err;
1195 
1196 	/* Write out trailing byte if it exists. */
1197 	if (actual != len) {
1198 		write_enable(nor);
1199 
1200 		nor->program_opcode = SPINOR_OP_BP;
1201 		ret = nor->write(nor, to, 1, buf + actual);
1202 		if (ret < 0)
1203 			goto sst_write_err;
1204 		ret = spi_nor_wait_till_ready(nor);
1205 		if (ret)
1206 			goto sst_write_err;
1207 		write_disable(nor);
1208 		actual += 1;
1209 	}
1210 sst_write_err:
1211 	*retlen += actual;
1212 	return ret;
1213 }
1214 #endif
1215 /*
1216  * Write an address range to the nor chip.  Data must be written in
1217  * FLASH_PAGESIZE chunks.  The address range may be any size provided
1218  * it is within the physical boundaries.
1219  */
1220 static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
1221 	size_t *retlen, const u_char *buf)
1222 {
1223 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1224 	size_t page_offset, page_remain, i;
1225 	ssize_t ret;
1226 
1227 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
1228 
1229 	for (i = 0; i < len; ) {
1230 		ssize_t written;
1231 		loff_t addr = to + i;
1232 
1233 		/*
1234 		 * If page_size is a power of two, the offset can be quickly
1235 		 * calculated with an AND operation. On the other cases we
1236 		 * need to do a modulus operation (more expensive).
1237 		 * Power of two numbers have only one bit set and we can use
1238 		 * the instruction hweight32 to detect if we need to do a
1239 		 * modulus (do_div()) or not.
1240 		 */
1241 		if (hweight32(nor->page_size) == 1) {
1242 			page_offset = addr & (nor->page_size - 1);
1243 		} else {
1244 			u64 aux = addr;
1245 
1246 			page_offset = do_div(aux, nor->page_size);
1247 		}
1248 		/* the size of data remaining on the first page */
1249 		page_remain = min_t(size_t,
1250 				    nor->page_size - page_offset, len - i);
1251 
1252 #ifdef CONFIG_SPI_FLASH_BAR
1253 		ret = write_bar(nor, addr);
1254 		if (ret < 0)
1255 			return ret;
1256 #endif
1257 		write_enable(nor);
1258 		ret = nor->write(nor, addr, page_remain, buf + i);
1259 		if (ret < 0)
1260 			goto write_err;
1261 		written = ret;
1262 
1263 		ret = spi_nor_wait_till_ready(nor);
1264 		if (ret)
1265 			goto write_err;
1266 		*retlen += written;
1267 		i += written;
1268 	}
1269 
1270 write_err:
1271 #ifdef CONFIG_SPI_FLASH_BAR
1272 	ret = clean_bar(nor);
1273 #endif
1274 	return ret;
1275 }
1276 
1277 #ifdef CONFIG_SPI_FLASH_MACRONIX
1278 /**
1279  * macronix_quad_enable() - set QE bit in Status Register.
1280  * @nor:	pointer to a 'struct spi_nor'
1281  *
1282  * Set the Quad Enable (QE) bit in the Status Register.
1283  *
1284  * bit 6 of the Status Register is the QE bit for Macronix like QSPI memories.
1285  *
1286  * Return: 0 on success, -errno otherwise.
1287  */
1288 static int macronix_quad_enable(struct spi_nor *nor)
1289 {
1290 	int ret, val;
1291 
1292 	val = read_sr(nor);
1293 	if (val < 0)
1294 		return val;
1295 	if (val & SR_QUAD_EN_MX)
1296 		return 0;
1297 
1298 	write_enable(nor);
1299 
1300 	write_sr(nor, val | SR_QUAD_EN_MX);
1301 
1302 	ret = spi_nor_wait_till_ready(nor);
1303 	if (ret)
1304 		return ret;
1305 
1306 	ret = read_sr(nor);
1307 	if (!(ret > 0 && (ret & SR_QUAD_EN_MX))) {
1308 		dev_err(nor->dev, "Macronix Quad bit not set\n");
1309 		return -EINVAL;
1310 	}
1311 
1312 	return 0;
1313 }
1314 #endif
1315 
1316 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
1317 /*
1318  * Write status Register and configuration register with 2 bytes
1319  * The first byte will be written to the status register, while the
1320  * second byte will be written to the configuration register.
1321  * Return negative if error occurred.
1322  */
1323 static int write_sr_cr(struct spi_nor *nor, u8 *sr_cr)
1324 {
1325 	int ret;
1326 
1327 	write_enable(nor);
1328 
1329 	ret = nor->write_reg(nor, SPINOR_OP_WRSR, sr_cr, 2);
1330 	if (ret < 0) {
1331 		dev_dbg(nor->dev,
1332 			"error while writing configuration register\n");
1333 		return -EINVAL;
1334 	}
1335 
1336 	ret = spi_nor_wait_till_ready(nor);
1337 	if (ret) {
1338 		dev_dbg(nor->dev,
1339 			"timeout while writing configuration register\n");
1340 		return ret;
1341 	}
1342 
1343 	return 0;
1344 }
1345 
1346 /**
1347  * spansion_read_cr_quad_enable() - set QE bit in Configuration Register.
1348  * @nor:	pointer to a 'struct spi_nor'
1349  *
1350  * Set the Quad Enable (QE) bit in the Configuration Register.
1351  * This function should be used with QSPI memories supporting the Read
1352  * Configuration Register (35h) instruction.
1353  *
1354  * bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
1355  * memories.
1356  *
1357  * Return: 0 on success, -errno otherwise.
1358  */
1359 static int spansion_read_cr_quad_enable(struct spi_nor *nor)
1360 {
1361 	u8 sr_cr[2];
1362 	int ret;
1363 
1364 	/* Check current Quad Enable bit value. */
1365 	ret = read_cr(nor);
1366 	if (ret < 0) {
1367 		dev_dbg(dev, "error while reading configuration register\n");
1368 		return -EINVAL;
1369 	}
1370 
1371 	if (ret & CR_QUAD_EN_SPAN)
1372 		return 0;
1373 
1374 	sr_cr[1] = ret | CR_QUAD_EN_SPAN;
1375 
1376 	/* Keep the current value of the Status Register. */
1377 	ret = read_sr(nor);
1378 	if (ret < 0) {
1379 		dev_dbg(dev, "error while reading status register\n");
1380 		return -EINVAL;
1381 	}
1382 	sr_cr[0] = ret;
1383 
1384 	ret = write_sr_cr(nor, sr_cr);
1385 	if (ret)
1386 		return ret;
1387 
1388 	/* Read back and check it. */
1389 	ret = read_cr(nor);
1390 	if (!(ret > 0 && (ret & CR_QUAD_EN_SPAN))) {
1391 		dev_dbg(nor->dev, "Spansion Quad bit not set\n");
1392 		return -EINVAL;
1393 	}
1394 
1395 	return 0;
1396 }
1397 
1398 #if CONFIG_IS_ENABLED(SPI_FLASH_SFDP_SUPPORT)
1399 /**
1400  * spansion_no_read_cr_quad_enable() - set QE bit in Configuration Register.
1401  * @nor:	pointer to a 'struct spi_nor'
1402  *
1403  * Set the Quad Enable (QE) bit in the Configuration Register.
1404  * This function should be used with QSPI memories not supporting the Read
1405  * Configuration Register (35h) instruction.
1406  *
1407  * bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
1408  * memories.
1409  *
1410  * Return: 0 on success, -errno otherwise.
1411  */
1412 static int spansion_no_read_cr_quad_enable(struct spi_nor *nor)
1413 {
1414 	u8 sr_cr[2];
1415 	int ret;
1416 
1417 	/* Keep the current value of the Status Register. */
1418 	ret = read_sr(nor);
1419 	if (ret < 0) {
1420 		dev_dbg(nor->dev, "error while reading status register\n");
1421 		return -EINVAL;
1422 	}
1423 	sr_cr[0] = ret;
1424 	sr_cr[1] = CR_QUAD_EN_SPAN;
1425 
1426 	return write_sr_cr(nor, sr_cr);
1427 }
1428 
1429 #endif /* CONFIG_SPI_FLASH_SFDP_SUPPORT */
1430 #endif /* CONFIG_SPI_FLASH_SPANSION */
1431 
1432 struct spi_nor_read_command {
1433 	u8			num_mode_clocks;
1434 	u8			num_wait_states;
1435 	u8			opcode;
1436 	enum spi_nor_protocol	proto;
1437 };
1438 
1439 struct spi_nor_pp_command {
1440 	u8			opcode;
1441 	enum spi_nor_protocol	proto;
1442 };
1443 
1444 enum spi_nor_read_command_index {
1445 	SNOR_CMD_READ,
1446 	SNOR_CMD_READ_FAST,
1447 	SNOR_CMD_READ_1_1_1_DTR,
1448 
1449 	/* Dual SPI */
1450 	SNOR_CMD_READ_1_1_2,
1451 	SNOR_CMD_READ_1_2_2,
1452 	SNOR_CMD_READ_2_2_2,
1453 	SNOR_CMD_READ_1_2_2_DTR,
1454 
1455 	/* Quad SPI */
1456 	SNOR_CMD_READ_1_1_4,
1457 	SNOR_CMD_READ_1_4_4,
1458 	SNOR_CMD_READ_4_4_4,
1459 	SNOR_CMD_READ_1_4_4_DTR,
1460 
1461 	/* Octo SPI */
1462 	SNOR_CMD_READ_1_1_8,
1463 	SNOR_CMD_READ_1_8_8,
1464 	SNOR_CMD_READ_8_8_8,
1465 	SNOR_CMD_READ_1_8_8_DTR,
1466 
1467 	SNOR_CMD_READ_MAX
1468 };
1469 
1470 enum spi_nor_pp_command_index {
1471 	SNOR_CMD_PP,
1472 
1473 	/* Quad SPI */
1474 	SNOR_CMD_PP_1_1_4,
1475 	SNOR_CMD_PP_1_4_4,
1476 	SNOR_CMD_PP_4_4_4,
1477 
1478 	/* Octo SPI */
1479 	SNOR_CMD_PP_1_1_8,
1480 	SNOR_CMD_PP_1_8_8,
1481 	SNOR_CMD_PP_8_8_8,
1482 
1483 	SNOR_CMD_PP_MAX
1484 };
1485 
1486 struct spi_nor_flash_parameter {
1487 	u64				size;
1488 	u32				page_size;
1489 
1490 	struct spi_nor_hwcaps		hwcaps;
1491 	struct spi_nor_read_command	reads[SNOR_CMD_READ_MAX];
1492 	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
1493 
1494 	int (*quad_enable)(struct spi_nor *nor);
1495 };
1496 
1497 static void
1498 spi_nor_set_read_settings(struct spi_nor_read_command *read,
1499 			  u8 num_mode_clocks,
1500 			  u8 num_wait_states,
1501 			  u8 opcode,
1502 			  enum spi_nor_protocol proto)
1503 {
1504 	read->num_mode_clocks = num_mode_clocks;
1505 	read->num_wait_states = num_wait_states;
1506 	read->opcode = opcode;
1507 	read->proto = proto;
1508 }
1509 
1510 static void
1511 spi_nor_set_pp_settings(struct spi_nor_pp_command *pp,
1512 			u8 opcode,
1513 			enum spi_nor_protocol proto)
1514 {
1515 	pp->opcode = opcode;
1516 	pp->proto = proto;
1517 }
1518 
1519 #if CONFIG_IS_ENABLED(SPI_FLASH_SFDP_SUPPORT)
1520 /*
1521  * Serial Flash Discoverable Parameters (SFDP) parsing.
1522  */
1523 
1524 /**
1525  * spi_nor_read_sfdp() - read Serial Flash Discoverable Parameters.
1526  * @nor:	pointer to a 'struct spi_nor'
1527  * @addr:	offset in the SFDP area to start reading data from
1528  * @len:	number of bytes to read
1529  * @buf:	buffer where the SFDP data are copied into (dma-safe memory)
1530  *
1531  * Whatever the actual numbers of bytes for address and dummy cycles are
1532  * for (Fast) Read commands, the Read SFDP (5Ah) instruction is always
1533  * followed by a 3-byte address and 8 dummy clock cycles.
1534  *
1535  * Return: 0 on success, -errno otherwise.
1536  */
1537 static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr,
1538 			     size_t len, void *buf)
1539 {
1540 	u8 addr_width, read_opcode, read_dummy;
1541 	int ret;
1542 
1543 	read_opcode = nor->read_opcode;
1544 	addr_width = nor->addr_width;
1545 	read_dummy = nor->read_dummy;
1546 
1547 	nor->read_opcode = SPINOR_OP_RDSFDP;
1548 	nor->addr_width = 3;
1549 	nor->read_dummy = 8;
1550 
1551 	while (len) {
1552 		ret = nor->read(nor, addr, len, (u8 *)buf);
1553 		if (!ret || ret > len) {
1554 			ret = -EIO;
1555 			goto read_err;
1556 		}
1557 		if (ret < 0)
1558 			goto read_err;
1559 
1560 		buf += ret;
1561 		addr += ret;
1562 		len -= ret;
1563 	}
1564 	ret = 0;
1565 
1566 read_err:
1567 	nor->read_opcode = read_opcode;
1568 	nor->addr_width = addr_width;
1569 	nor->read_dummy = read_dummy;
1570 
1571 	return ret;
1572 }
1573 
1574 struct sfdp_parameter_header {
1575 	u8		id_lsb;
1576 	u8		minor;
1577 	u8		major;
1578 	u8		length; /* in double words */
1579 	u8		parameter_table_pointer[3]; /* byte address */
1580 	u8		id_msb;
1581 };
1582 
1583 #define SFDP_PARAM_HEADER_ID(p)	(((p)->id_msb << 8) | (p)->id_lsb)
1584 #define SFDP_PARAM_HEADER_PTP(p) \
1585 	(((p)->parameter_table_pointer[2] << 16) | \
1586 	 ((p)->parameter_table_pointer[1] <<  8) | \
1587 	 ((p)->parameter_table_pointer[0] <<  0))
1588 
1589 #define SFDP_BFPT_ID		0xff00	/* Basic Flash Parameter Table */
1590 #define SFDP_SECTOR_MAP_ID	0xff81	/* Sector Map Table */
1591 
1592 #define SFDP_SIGNATURE		0x50444653U
1593 #define SFDP_JESD216_MAJOR	1
1594 #define SFDP_JESD216_MINOR	0
1595 #define SFDP_JESD216A_MINOR	5
1596 #define SFDP_JESD216B_MINOR	6
1597 
1598 struct sfdp_header {
1599 	u32		signature; /* Ox50444653U <=> "SFDP" */
1600 	u8		minor;
1601 	u8		major;
1602 	u8		nph; /* 0-base number of parameter headers */
1603 	u8		unused;
1604 
1605 	/* Basic Flash Parameter Table. */
1606 	struct sfdp_parameter_header	bfpt_header;
1607 };
1608 
1609 /* Basic Flash Parameter Table */
1610 
1611 /*
1612  * JESD216 rev B defines a Basic Flash Parameter Table of 16 DWORDs.
1613  * They are indexed from 1 but C arrays are indexed from 0.
1614  */
1615 #define BFPT_DWORD(i)		((i) - 1)
1616 #define BFPT_DWORD_MAX		16
1617 
1618 /* The first version of JESB216 defined only 9 DWORDs. */
1619 #define BFPT_DWORD_MAX_JESD216			9
1620 
1621 /* 1st DWORD. */
1622 #define BFPT_DWORD1_FAST_READ_1_1_2		BIT(16)
1623 #define BFPT_DWORD1_ADDRESS_BYTES_MASK		GENMASK(18, 17)
1624 #define BFPT_DWORD1_ADDRESS_BYTES_3_ONLY	(0x0UL << 17)
1625 #define BFPT_DWORD1_ADDRESS_BYTES_3_OR_4	(0x1UL << 17)
1626 #define BFPT_DWORD1_ADDRESS_BYTES_4_ONLY	(0x2UL << 17)
1627 #define BFPT_DWORD1_DTR				BIT(19)
1628 #define BFPT_DWORD1_FAST_READ_1_2_2		BIT(20)
1629 #define BFPT_DWORD1_FAST_READ_1_4_4		BIT(21)
1630 #define BFPT_DWORD1_FAST_READ_1_1_4		BIT(22)
1631 
1632 /* 5th DWORD. */
1633 #define BFPT_DWORD5_FAST_READ_2_2_2		BIT(0)
1634 #define BFPT_DWORD5_FAST_READ_4_4_4		BIT(4)
1635 
1636 /* 11th DWORD. */
1637 #define BFPT_DWORD11_PAGE_SIZE_SHIFT		4
1638 #define BFPT_DWORD11_PAGE_SIZE_MASK		GENMASK(7, 4)
1639 
1640 /* 15th DWORD. */
1641 
1642 /*
1643  * (from JESD216 rev B)
1644  * Quad Enable Requirements (QER):
1645  * - 000b: Device does not have a QE bit. Device detects 1-1-4 and 1-4-4
1646  *         reads based on instruction. DQ3/HOLD# functions are hold during
1647  *         instruction phase.
1648  * - 001b: QE is bit 1 of status register 2. It is set via Write Status with
1649  *         two data bytes where bit 1 of the second byte is one.
1650  *         [...]
1651  *         Writing only one byte to the status register has the side-effect of
1652  *         clearing status register 2, including the QE bit. The 100b code is
1653  *         used if writing one byte to the status register does not modify
1654  *         status register 2.
1655  * - 010b: QE is bit 6 of status register 1. It is set via Write Status with
1656  *         one data byte where bit 6 is one.
1657  *         [...]
1658  * - 011b: QE is bit 7 of status register 2. It is set via Write status
1659  *         register 2 instruction 3Eh with one data byte where bit 7 is one.
1660  *         [...]
1661  *         The status register 2 is read using instruction 3Fh.
1662  * - 100b: QE is bit 1 of status register 2. It is set via Write Status with
1663  *         two data bytes where bit 1 of the second byte is one.
1664  *         [...]
1665  *         In contrast to the 001b code, writing one byte to the status
1666  *         register does not modify status register 2.
1667  * - 101b: QE is bit 1 of status register 2. Status register 1 is read using
1668  *         Read Status instruction 05h. Status register2 is read using
1669  *         instruction 35h. QE is set via Writ Status instruction 01h with
1670  *         two data bytes where bit 1 of the second byte is one.
1671  *         [...]
1672  */
1673 #define BFPT_DWORD15_QER_MASK			GENMASK(22, 20)
1674 #define BFPT_DWORD15_QER_NONE			(0x0UL << 20) /* Micron */
1675 #define BFPT_DWORD15_QER_SR2_BIT1_BUGGY		(0x1UL << 20)
1676 #define BFPT_DWORD15_QER_SR1_BIT6		(0x2UL << 20) /* Macronix */
1677 #define BFPT_DWORD15_QER_SR2_BIT7		(0x3UL << 20)
1678 #define BFPT_DWORD15_QER_SR2_BIT1_NO_RD		(0x4UL << 20)
1679 #define BFPT_DWORD15_QER_SR2_BIT1		(0x5UL << 20) /* Spansion */
1680 
1681 struct sfdp_bfpt {
1682 	u32	dwords[BFPT_DWORD_MAX];
1683 };
1684 
1685 /* Fast Read settings. */
1686 
1687 static void
1688 spi_nor_set_read_settings_from_bfpt(struct spi_nor_read_command *read,
1689 				    u16 half,
1690 				    enum spi_nor_protocol proto)
1691 {
1692 	read->num_mode_clocks = (half >> 5) & 0x07;
1693 	read->num_wait_states = (half >> 0) & 0x1f;
1694 	read->opcode = (half >> 8) & 0xff;
1695 	read->proto = proto;
1696 }
1697 
1698 struct sfdp_bfpt_read {
1699 	/* The Fast Read x-y-z hardware capability in params->hwcaps.mask. */
1700 	u32			hwcaps;
1701 
1702 	/*
1703 	 * The <supported_bit> bit in <supported_dword> BFPT DWORD tells us
1704 	 * whether the Fast Read x-y-z command is supported.
1705 	 */
1706 	u32			supported_dword;
1707 	u32			supported_bit;
1708 
1709 	/*
1710 	 * The half-word at offset <setting_shift> in <setting_dword> BFPT DWORD
1711 	 * encodes the op code, the number of mode clocks and the number of wait
1712 	 * states to be used by Fast Read x-y-z command.
1713 	 */
1714 	u32			settings_dword;
1715 	u32			settings_shift;
1716 
1717 	/* The SPI protocol for this Fast Read x-y-z command. */
1718 	enum spi_nor_protocol	proto;
1719 };
1720 
1721 static const struct sfdp_bfpt_read sfdp_bfpt_reads[] = {
1722 	/* Fast Read 1-1-2 */
1723 	{
1724 		SNOR_HWCAPS_READ_1_1_2,
1725 		BFPT_DWORD(1), BIT(16),	/* Supported bit */
1726 		BFPT_DWORD(4), 0,	/* Settings */
1727 		SNOR_PROTO_1_1_2,
1728 	},
1729 
1730 	/* Fast Read 1-2-2 */
1731 	{
1732 		SNOR_HWCAPS_READ_1_2_2,
1733 		BFPT_DWORD(1), BIT(20),	/* Supported bit */
1734 		BFPT_DWORD(4), 16,	/* Settings */
1735 		SNOR_PROTO_1_2_2,
1736 	},
1737 
1738 	/* Fast Read 2-2-2 */
1739 	{
1740 		SNOR_HWCAPS_READ_2_2_2,
1741 		BFPT_DWORD(5),  BIT(0),	/* Supported bit */
1742 		BFPT_DWORD(6), 16,	/* Settings */
1743 		SNOR_PROTO_2_2_2,
1744 	},
1745 
1746 	/* Fast Read 1-1-4 */
1747 	{
1748 		SNOR_HWCAPS_READ_1_1_4,
1749 		BFPT_DWORD(1), BIT(22),	/* Supported bit */
1750 		BFPT_DWORD(3), 16,	/* Settings */
1751 		SNOR_PROTO_1_1_4,
1752 	},
1753 
1754 	/* Fast Read 1-4-4 */
1755 	{
1756 		SNOR_HWCAPS_READ_1_4_4,
1757 		BFPT_DWORD(1), BIT(21),	/* Supported bit */
1758 		BFPT_DWORD(3), 0,	/* Settings */
1759 		SNOR_PROTO_1_4_4,
1760 	},
1761 
1762 	/* Fast Read 4-4-4 */
1763 	{
1764 		SNOR_HWCAPS_READ_4_4_4,
1765 		BFPT_DWORD(5), BIT(4),	/* Supported bit */
1766 		BFPT_DWORD(7), 16,	/* Settings */
1767 		SNOR_PROTO_4_4_4,
1768 	},
1769 };
1770 
1771 struct sfdp_bfpt_erase {
1772 	/*
1773 	 * The half-word at offset <shift> in DWORD <dwoard> encodes the
1774 	 * op code and erase sector size to be used by Sector Erase commands.
1775 	 */
1776 	u32			dword;
1777 	u32			shift;
1778 };
1779 
1780 static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
1781 	/* Erase Type 1 in DWORD8 bits[15:0] */
1782 	{BFPT_DWORD(8), 0},
1783 
1784 	/* Erase Type 2 in DWORD8 bits[31:16] */
1785 	{BFPT_DWORD(8), 16},
1786 
1787 	/* Erase Type 3 in DWORD9 bits[15:0] */
1788 	{BFPT_DWORD(9), 0},
1789 
1790 	/* Erase Type 4 in DWORD9 bits[31:16] */
1791 	{BFPT_DWORD(9), 16},
1792 };
1793 
1794 static int spi_nor_hwcaps_read2cmd(u32 hwcaps);
1795 
1796 /**
1797  * spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
1798  * @nor:		pointer to a 'struct spi_nor'
1799  * @bfpt_header:	pointer to the 'struct sfdp_parameter_header' describing
1800  *			the Basic Flash Parameter Table length and version
1801  * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
1802  *			filled
1803  *
1804  * The Basic Flash Parameter Table is the main and only mandatory table as
1805  * defined by the SFDP (JESD216) specification.
1806  * It provides us with the total size (memory density) of the data array and
1807  * the number of address bytes for Fast Read, Page Program and Sector Erase
1808  * commands.
1809  * For Fast READ commands, it also gives the number of mode clock cycles and
1810  * wait states (regrouped in the number of dummy clock cycles) for each
1811  * supported instruction op code.
1812  * For Page Program, the page size is now available since JESD216 rev A, however
1813  * the supported instruction op codes are still not provided.
1814  * For Sector Erase commands, this table stores the supported instruction op
1815  * codes and the associated sector sizes.
1816  * Finally, the Quad Enable Requirements (QER) are also available since JESD216
1817  * rev A. The QER bits encode the manufacturer dependent procedure to be
1818  * executed to set the Quad Enable (QE) bit in some internal register of the
1819  * Quad SPI memory. Indeed the QE bit, when it exists, must be set before
1820  * sending any Quad SPI command to the memory. Actually, setting the QE bit
1821  * tells the memory to reassign its WP# and HOLD#/RESET# pins to functions IO2
1822  * and IO3 hence enabling 4 (Quad) I/O lines.
1823  *
1824  * Return: 0 on success, -errno otherwise.
1825  */
1826 static int spi_nor_parse_bfpt(struct spi_nor *nor,
1827 			      const struct sfdp_parameter_header *bfpt_header,
1828 			      struct spi_nor_flash_parameter *params)
1829 {
1830 	struct mtd_info *mtd = &nor->mtd;
1831 	struct sfdp_bfpt bfpt;
1832 	size_t len;
1833 	int i, cmd, err;
1834 	u32 addr;
1835 	u16 half;
1836 
1837 	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
1838 	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
1839 		return -EINVAL;
1840 
1841 	/* Read the Basic Flash Parameter Table. */
1842 	len = min_t(size_t, sizeof(bfpt),
1843 		    bfpt_header->length * sizeof(u32));
1844 	addr = SFDP_PARAM_HEADER_PTP(bfpt_header);
1845 	memset(&bfpt, 0, sizeof(bfpt));
1846 	err = spi_nor_read_sfdp(nor,  addr, len, &bfpt);
1847 	if (err < 0)
1848 		return err;
1849 
1850 	/* Fix endianness of the BFPT DWORDs. */
1851 	for (i = 0; i < BFPT_DWORD_MAX; i++)
1852 		bfpt.dwords[i] = le32_to_cpu(bfpt.dwords[i]);
1853 
1854 	/* Number of address bytes. */
1855 	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
1856 	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
1857 		nor->addr_width = 3;
1858 		break;
1859 
1860 	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
1861 		nor->addr_width = 4;
1862 		break;
1863 
1864 	default:
1865 		break;
1866 	}
1867 
1868 	/* Flash Memory Density (in bits). */
1869 	params->size = bfpt.dwords[BFPT_DWORD(2)];
1870 	if (params->size & BIT(31)) {
1871 		params->size &= ~BIT(31);
1872 
1873 		/*
1874 		 * Prevent overflows on params->size. Anyway, a NOR of 2^64
1875 		 * bits is unlikely to exist so this error probably means
1876 		 * the BFPT we are reading is corrupted/wrong.
1877 		 */
1878 		if (params->size > 63)
1879 			return -EINVAL;
1880 
1881 		params->size = 1ULL << params->size;
1882 	} else {
1883 		params->size++;
1884 	}
1885 	params->size >>= 3; /* Convert to bytes. */
1886 
1887 	/* Fast Read settings. */
1888 	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
1889 		const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
1890 		struct spi_nor_read_command *read;
1891 
1892 		if (!(bfpt.dwords[rd->supported_dword] & rd->supported_bit)) {
1893 			params->hwcaps.mask &= ~rd->hwcaps;
1894 			continue;
1895 		}
1896 
1897 		params->hwcaps.mask |= rd->hwcaps;
1898 		cmd = spi_nor_hwcaps_read2cmd(rd->hwcaps);
1899 		read = &params->reads[cmd];
1900 		half = bfpt.dwords[rd->settings_dword] >> rd->settings_shift;
1901 		spi_nor_set_read_settings_from_bfpt(read, half, rd->proto);
1902 	}
1903 
1904 	/* Sector Erase settings. */
1905 	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_erases); i++) {
1906 		const struct sfdp_bfpt_erase *er = &sfdp_bfpt_erases[i];
1907 		u32 erasesize;
1908 		u8 opcode;
1909 
1910 		half = bfpt.dwords[er->dword] >> er->shift;
1911 		erasesize = half & 0xff;
1912 
1913 		/* erasesize == 0 means this Erase Type is not supported. */
1914 		if (!erasesize)
1915 			continue;
1916 
1917 		erasesize = 1U << erasesize;
1918 		opcode = (half >> 8) & 0xff;
1919 #ifdef CONFIG_MTD_SPI_NOR_USE_4K_SECTORS
1920 		if (erasesize == SZ_4K) {
1921 			nor->erase_opcode = opcode;
1922 			mtd->erasesize = erasesize;
1923 			break;
1924 		}
1925 #endif
1926 		if (!mtd->erasesize || mtd->erasesize < erasesize) {
1927 			nor->erase_opcode = opcode;
1928 			mtd->erasesize = erasesize;
1929 		}
1930 	}
1931 
1932 	/* Stop here if not JESD216 rev A or later. */
1933 	if (bfpt_header->length < BFPT_DWORD_MAX)
1934 		return 0;
1935 
1936 	/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
1937 	params->page_size = bfpt.dwords[BFPT_DWORD(11)];
1938 	params->page_size &= BFPT_DWORD11_PAGE_SIZE_MASK;
1939 	params->page_size >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
1940 	params->page_size = 1U << params->page_size;
1941 
1942 	/* Quad Enable Requirements. */
1943 	switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
1944 	case BFPT_DWORD15_QER_NONE:
1945 		params->quad_enable = NULL;
1946 		break;
1947 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
1948 	case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
1949 	case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
1950 		params->quad_enable = spansion_no_read_cr_quad_enable;
1951 		break;
1952 #endif
1953 #ifdef CONFIG_SPI_FLASH_MACRONIX
1954 	case BFPT_DWORD15_QER_SR1_BIT6:
1955 		params->quad_enable = macronix_quad_enable;
1956 		break;
1957 #endif
1958 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
1959 	case BFPT_DWORD15_QER_SR2_BIT1:
1960 		params->quad_enable = spansion_read_cr_quad_enable;
1961 		break;
1962 #endif
1963 	default:
1964 		return -EINVAL;
1965 	}
1966 
1967 	return 0;
1968 }
1969 
1970 /**
1971  * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
1972  * @nor:		pointer to a 'struct spi_nor'
1973  * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
1974  *			filled
1975  *
1976  * The Serial Flash Discoverable Parameters are described by the JEDEC JESD216
1977  * specification. This is a standard which tends to supported by almost all
1978  * (Q)SPI memory manufacturers. Those hard-coded tables allow us to learn at
1979  * runtime the main parameters needed to perform basic SPI flash operations such
1980  * as Fast Read, Page Program or Sector Erase commands.
1981  *
1982  * Return: 0 on success, -errno otherwise.
1983  */
1984 static int spi_nor_parse_sfdp(struct spi_nor *nor,
1985 			      struct spi_nor_flash_parameter *params)
1986 {
1987 	const struct sfdp_parameter_header *param_header, *bfpt_header;
1988 	struct sfdp_parameter_header *param_headers = NULL;
1989 	struct sfdp_header header;
1990 	size_t psize;
1991 	int i, err;
1992 
1993 	/* Get the SFDP header. */
1994 	err = spi_nor_read_sfdp(nor, 0, sizeof(header), &header);
1995 	if (err < 0)
1996 		return err;
1997 
1998 	/* Check the SFDP header version. */
1999 	if (le32_to_cpu(header.signature) != SFDP_SIGNATURE ||
2000 	    header.major != SFDP_JESD216_MAJOR)
2001 		return -EINVAL;
2002 
2003 	/*
2004 	 * Verify that the first and only mandatory parameter header is a
2005 	 * Basic Flash Parameter Table header as specified in JESD216.
2006 	 */
2007 	bfpt_header = &header.bfpt_header;
2008 	if (SFDP_PARAM_HEADER_ID(bfpt_header) != SFDP_BFPT_ID ||
2009 	    bfpt_header->major != SFDP_JESD216_MAJOR)
2010 		return -EINVAL;
2011 
2012 	/*
2013 	 * Allocate memory then read all parameter headers with a single
2014 	 * Read SFDP command. These parameter headers will actually be parsed
2015 	 * twice: a first time to get the latest revision of the basic flash
2016 	 * parameter table, then a second time to handle the supported optional
2017 	 * tables.
2018 	 * Hence we read the parameter headers once for all to reduce the
2019 	 * processing time. Also we use kmalloc() instead of devm_kmalloc()
2020 	 * because we don't need to keep these parameter headers: the allocated
2021 	 * memory is always released with kfree() before exiting this function.
2022 	 */
2023 	if (header.nph) {
2024 		psize = header.nph * sizeof(*param_headers);
2025 
2026 		param_headers = kmalloc(psize, GFP_KERNEL);
2027 		if (!param_headers)
2028 			return -ENOMEM;
2029 
2030 		err = spi_nor_read_sfdp(nor, sizeof(header),
2031 					psize, param_headers);
2032 		if (err < 0) {
2033 			dev_err(dev, "failed to read SFDP parameter headers\n");
2034 			goto exit;
2035 		}
2036 	}
2037 
2038 	/*
2039 	 * Check other parameter headers to get the latest revision of
2040 	 * the basic flash parameter table.
2041 	 */
2042 	for (i = 0; i < header.nph; i++) {
2043 		param_header = &param_headers[i];
2044 
2045 		if (SFDP_PARAM_HEADER_ID(param_header) == SFDP_BFPT_ID &&
2046 		    param_header->major == SFDP_JESD216_MAJOR &&
2047 		    (param_header->minor > bfpt_header->minor ||
2048 		     (param_header->minor == bfpt_header->minor &&
2049 		      param_header->length > bfpt_header->length)))
2050 			bfpt_header = param_header;
2051 	}
2052 
2053 	err = spi_nor_parse_bfpt(nor, bfpt_header, params);
2054 	if (err)
2055 		goto exit;
2056 
2057 	/* Parse other parameter headers. */
2058 	for (i = 0; i < header.nph; i++) {
2059 		param_header = &param_headers[i];
2060 
2061 		switch (SFDP_PARAM_HEADER_ID(param_header)) {
2062 		case SFDP_SECTOR_MAP_ID:
2063 			dev_info(dev, "non-uniform erase sector maps are not supported yet.\n");
2064 			break;
2065 
2066 		default:
2067 			break;
2068 		}
2069 
2070 		if (err)
2071 			goto exit;
2072 	}
2073 
2074 exit:
2075 	kfree(param_headers);
2076 	return err;
2077 }
2078 #else
2079 static int spi_nor_parse_sfdp(struct spi_nor *nor,
2080 			      struct spi_nor_flash_parameter *params)
2081 {
2082 	return -EINVAL;
2083 }
2084 #endif /* SPI_FLASH_SFDP_SUPPORT */
2085 
2086 static int spi_nor_init_params(struct spi_nor *nor,
2087 			       const struct flash_info *info,
2088 			       struct spi_nor_flash_parameter *params)
2089 {
2090 	/* Set legacy flash parameters as default. */
2091 	memset(params, 0, sizeof(*params));
2092 
2093 	/* Set SPI NOR sizes. */
2094 	params->size = info->sector_size * info->n_sectors;
2095 	params->page_size = info->page_size;
2096 
2097 	/* (Fast) Read settings. */
2098 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
2099 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
2100 				  0, 0, SPINOR_OP_READ,
2101 				  SNOR_PROTO_1_1_1);
2102 
2103 	if (!(info->flags & SPI_NOR_NO_FR)) {
2104 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
2105 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
2106 					  0, 8, SPINOR_OP_READ_FAST,
2107 					  SNOR_PROTO_1_1_1);
2108 	}
2109 
2110 	if (info->flags & SPI_NOR_DUAL_READ) {
2111 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2112 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2113 					  0, 8, SPINOR_OP_READ_1_1_2,
2114 					  SNOR_PROTO_1_1_2);
2115 	}
2116 
2117 	if (info->flags & SPI_NOR_QUAD_READ) {
2118 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2119 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2120 					  0, 8, SPINOR_OP_READ_1_1_4,
2121 					  SNOR_PROTO_1_1_4);
2122 	}
2123 
2124 	/* Page Program settings. */
2125 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
2126 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
2127 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
2128 
2129 	if (info->flags & SPI_NOR_QUAD_READ) {
2130 		params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
2131 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
2132 					SPINOR_OP_PP_1_1_4, SNOR_PROTO_1_1_4);
2133 	}
2134 
2135 	/* Select the procedure to set the Quad Enable bit. */
2136 	if (params->hwcaps.mask & (SNOR_HWCAPS_READ_QUAD |
2137 				   SNOR_HWCAPS_PP_QUAD)) {
2138 		switch (JEDEC_MFR(info)) {
2139 #ifdef CONFIG_SPI_FLASH_MACRONIX
2140 		case SNOR_MFR_MACRONIX:
2141 			params->quad_enable = macronix_quad_enable;
2142 			break;
2143 #endif
2144 		case SNOR_MFR_ST:
2145 		case SNOR_MFR_MICRON:
2146 			break;
2147 
2148 		default:
2149 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
2150 			/* Kept only for backward compatibility purpose. */
2151 			params->quad_enable = spansion_read_cr_quad_enable;
2152 #endif
2153 			break;
2154 		}
2155 	}
2156 
2157 	/* Override the parameters with data read from SFDP tables. */
2158 	nor->addr_width = 0;
2159 	nor->mtd.erasesize = 0;
2160 	if ((info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
2161 	    !(info->flags & SPI_NOR_SKIP_SFDP)) {
2162 		struct spi_nor_flash_parameter sfdp_params;
2163 
2164 		memcpy(&sfdp_params, params, sizeof(sfdp_params));
2165 		if (spi_nor_parse_sfdp(nor, &sfdp_params)) {
2166 			nor->addr_width = 0;
2167 			nor->mtd.erasesize = 0;
2168 		} else {
2169 			memcpy(params, &sfdp_params, sizeof(*params));
2170 		}
2171 	}
2172 
2173 	return 0;
2174 }
2175 
2176 static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2177 {
2178 	size_t i;
2179 
2180 	for (i = 0; i < size; i++)
2181 		if (table[i][0] == (int)hwcaps)
2182 			return table[i][1];
2183 
2184 	return -EINVAL;
2185 }
2186 
2187 static int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2188 {
2189 	static const int hwcaps_read2cmd[][2] = {
2190 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2191 		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2192 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2193 		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2194 		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2195 		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2196 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2197 		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2198 		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2199 		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2200 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2201 		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2202 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2203 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2204 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2205 	};
2206 
2207 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2208 				  ARRAY_SIZE(hwcaps_read2cmd));
2209 }
2210 
2211 static int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2212 {
2213 	static const int hwcaps_pp2cmd[][2] = {
2214 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2215 		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2216 		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2217 		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2218 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2219 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2220 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2221 	};
2222 
2223 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2224 				  ARRAY_SIZE(hwcaps_pp2cmd));
2225 }
2226 
2227 static int spi_nor_select_read(struct spi_nor *nor,
2228 			       const struct spi_nor_flash_parameter *params,
2229 			       u32 shared_hwcaps)
2230 {
2231 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2232 	const struct spi_nor_read_command *read;
2233 
2234 	if (best_match < 0)
2235 		return -EINVAL;
2236 
2237 	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2238 	if (cmd < 0)
2239 		return -EINVAL;
2240 
2241 	read = &params->reads[cmd];
2242 	nor->read_opcode = read->opcode;
2243 	nor->read_proto = read->proto;
2244 
2245 	/*
2246 	 * In the spi-nor framework, we don't need to make the difference
2247 	 * between mode clock cycles and wait state clock cycles.
2248 	 * Indeed, the value of the mode clock cycles is used by a QSPI
2249 	 * flash memory to know whether it should enter or leave its 0-4-4
2250 	 * (Continuous Read / XIP) mode.
2251 	 * eXecution In Place is out of the scope of the mtd sub-system.
2252 	 * Hence we choose to merge both mode and wait state clock cycles
2253 	 * into the so called dummy clock cycles.
2254 	 */
2255 	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2256 	return 0;
2257 }
2258 
2259 static int spi_nor_select_pp(struct spi_nor *nor,
2260 			     const struct spi_nor_flash_parameter *params,
2261 			     u32 shared_hwcaps)
2262 {
2263 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2264 	const struct spi_nor_pp_command *pp;
2265 
2266 	if (best_match < 0)
2267 		return -EINVAL;
2268 
2269 	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2270 	if (cmd < 0)
2271 		return -EINVAL;
2272 
2273 	pp = &params->page_programs[cmd];
2274 	nor->program_opcode = pp->opcode;
2275 	nor->write_proto = pp->proto;
2276 	return 0;
2277 }
2278 
2279 static int spi_nor_select_erase(struct spi_nor *nor,
2280 				const struct flash_info *info)
2281 {
2282 	struct mtd_info *mtd = &nor->mtd;
2283 
2284 	/* Do nothing if already configured from SFDP. */
2285 	if (mtd->erasesize)
2286 		return 0;
2287 
2288 #ifdef CONFIG_SPI_FLASH_USE_4K_SECTORS
2289 	/* prefer "small sector" erase if possible */
2290 	if (info->flags & SECT_4K) {
2291 		nor->erase_opcode = SPINOR_OP_BE_4K;
2292 		mtd->erasesize = 4096;
2293 	} else if (info->flags & SECT_4K_PMC) {
2294 		nor->erase_opcode = SPINOR_OP_BE_4K_PMC;
2295 		mtd->erasesize = 4096;
2296 	} else
2297 #endif
2298 	{
2299 		nor->erase_opcode = SPINOR_OP_SE;
2300 		mtd->erasesize = info->sector_size;
2301 	}
2302 	return 0;
2303 }
2304 
2305 static int spi_nor_setup(struct spi_nor *nor, const struct flash_info *info,
2306 			 const struct spi_nor_flash_parameter *params,
2307 			 const struct spi_nor_hwcaps *hwcaps)
2308 {
2309 	u32 ignored_mask, shared_mask;
2310 	bool enable_quad_io;
2311 	int err;
2312 
2313 	/*
2314 	 * Keep only the hardware capabilities supported by both the SPI
2315 	 * controller and the SPI flash memory.
2316 	 */
2317 	shared_mask = hwcaps->mask & params->hwcaps.mask;
2318 
2319 	/* SPI n-n-n protocols are not supported yet. */
2320 	ignored_mask = (SNOR_HWCAPS_READ_2_2_2 |
2321 			SNOR_HWCAPS_READ_4_4_4 |
2322 			SNOR_HWCAPS_READ_8_8_8 |
2323 			SNOR_HWCAPS_PP_4_4_4 |
2324 			SNOR_HWCAPS_PP_8_8_8);
2325 	if (shared_mask & ignored_mask) {
2326 		dev_dbg(nor->dev,
2327 			"SPI n-n-n protocols are not supported yet.\n");
2328 		shared_mask &= ~ignored_mask;
2329 	}
2330 
2331 	/* Select the (Fast) Read command. */
2332 	err = spi_nor_select_read(nor, params, shared_mask);
2333 	if (err) {
2334 		dev_dbg(nor->dev,
2335 			"can't select read settings supported by both the SPI controller and memory.\n");
2336 		return err;
2337 	}
2338 
2339 	/* Select the Page Program command. */
2340 	err = spi_nor_select_pp(nor, params, shared_mask);
2341 	if (err) {
2342 		dev_dbg(nor->dev,
2343 			"can't select write settings supported by both the SPI controller and memory.\n");
2344 		return err;
2345 	}
2346 
2347 	/* Select the Sector Erase command. */
2348 	err = spi_nor_select_erase(nor, info);
2349 	if (err) {
2350 		dev_dbg(nor->dev,
2351 			"can't select erase settings supported by both the SPI controller and memory.\n");
2352 		return err;
2353 	}
2354 
2355 	/* Enable Quad I/O if needed. */
2356 	enable_quad_io = (spi_nor_get_protocol_width(nor->read_proto) == 4 ||
2357 			  spi_nor_get_protocol_width(nor->write_proto) == 4);
2358 	if (enable_quad_io && params->quad_enable)
2359 		nor->quad_enable = params->quad_enable;
2360 	else
2361 		nor->quad_enable = NULL;
2362 
2363 	return 0;
2364 }
2365 
2366 static int spi_nor_init(struct spi_nor *nor)
2367 {
2368 	int err;
2369 
2370 	/*
2371 	 * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up
2372 	 * with the software protection bits set
2373 	 */
2374 	if (JEDEC_MFR(nor->info) == SNOR_MFR_ATMEL ||
2375 	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
2376 	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
2377 	    nor->info->flags & SPI_NOR_HAS_LOCK) {
2378 		write_enable(nor);
2379 		write_sr(nor, 0);
2380 		spi_nor_wait_till_ready(nor);
2381 	}
2382 
2383 	if (nor->quad_enable) {
2384 		err = nor->quad_enable(nor);
2385 		if (err) {
2386 			dev_dbg(nor->dev, "quad mode not supported\n");
2387 			return err;
2388 		}
2389 	}
2390 
2391 	if (nor->addr_width == 4 &&
2392 	    (JEDEC_MFR(nor->info) != SNOR_MFR_SPANSION) &&
2393 	    !(nor->info->flags & SPI_NOR_4B_OPCODES)) {
2394 		/*
2395 		 * If the RESET# pin isn't hooked up properly, or the system
2396 		 * otherwise doesn't perform a reset command in the boot
2397 		 * sequence, it's impossible to 100% protect against unexpected
2398 		 * reboots (e.g., crashes). Warn the user (or hopefully, system
2399 		 * designer) that this is bad.
2400 		 */
2401 		if (nor->flags & SNOR_F_BROKEN_RESET)
2402 			printf("enabling reset hack; may not recover from unexpected reboots\n");
2403 		set_4byte(nor, nor->info, 1);
2404 	}
2405 
2406 	return 0;
2407 }
2408 
2409 int spi_nor_scan(struct spi_nor *nor)
2410 {
2411 	struct spi_nor_flash_parameter params;
2412 	const struct flash_info *info = NULL;
2413 	struct mtd_info *mtd = &nor->mtd;
2414 	struct spi_nor_hwcaps hwcaps = {
2415 		.mask = SNOR_HWCAPS_READ |
2416 			SNOR_HWCAPS_READ_FAST |
2417 			SNOR_HWCAPS_PP,
2418 	};
2419 	struct spi_slave *spi = nor->spi;
2420 	int ret;
2421 
2422 	/* Reset SPI protocol for all commands. */
2423 	nor->reg_proto = SNOR_PROTO_1_1_1;
2424 	nor->read_proto = SNOR_PROTO_1_1_1;
2425 	nor->write_proto = SNOR_PROTO_1_1_1;
2426 	nor->read = spi_nor_read_data;
2427 	nor->write = spi_nor_write_data;
2428 	nor->read_reg = spi_nor_read_reg;
2429 	nor->write_reg = spi_nor_write_reg;
2430 
2431 	if (spi->mode & SPI_RX_QUAD) {
2432 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2433 
2434 		if (spi->mode & SPI_TX_QUAD)
2435 			hwcaps.mask |= (SNOR_HWCAPS_READ_1_4_4 |
2436 					SNOR_HWCAPS_PP_1_1_4 |
2437 					SNOR_HWCAPS_PP_1_4_4);
2438 	} else if (spi->mode & SPI_RX_DUAL) {
2439 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2440 
2441 		if (spi->mode & SPI_TX_DUAL)
2442 			hwcaps.mask |= SNOR_HWCAPS_READ_1_2_2;
2443 	}
2444 
2445 	info = spi_nor_read_id(nor);
2446 	if (IS_ERR_OR_NULL(info))
2447 		return -ENOENT;
2448 	/* Parse the Serial Flash Discoverable Parameters table. */
2449 	ret = spi_nor_init_params(nor, info, &params);
2450 	if (ret)
2451 		return ret;
2452 
2453 	if (!mtd->name)
2454 		mtd->name = info->name;
2455 	mtd->priv = nor;
2456 	mtd->type = MTD_NORFLASH;
2457 	mtd->writesize = 1;
2458 	mtd->flags = MTD_CAP_NORFLASH;
2459 	mtd->size = params.size;
2460 	mtd->_erase = spi_nor_erase;
2461 	mtd->_read = spi_nor_read;
2462 
2463 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
2464 	/* NOR protection support for STmicro/Micron chips and similar */
2465 	if (JEDEC_MFR(info) == SNOR_MFR_ST ||
2466 	    JEDEC_MFR(info) == SNOR_MFR_MICRON ||
2467 	    JEDEC_MFR(info) == SNOR_MFR_SST ||
2468 			info->flags & SPI_NOR_HAS_LOCK) {
2469 		nor->flash_lock = stm_lock;
2470 		nor->flash_unlock = stm_unlock;
2471 		nor->flash_is_locked = stm_is_locked;
2472 	}
2473 #endif
2474 
2475 #ifdef CONFIG_SPI_FLASH_SST
2476 	/*
2477 	 * sst26 series block protection implementation differs from other
2478 	 * series.
2479 	 */
2480 	if (info->flags & SPI_NOR_HAS_SST26LOCK) {
2481 		nor->flash_lock = sst26_lock;
2482 		nor->flash_unlock = sst26_unlock;
2483 		nor->flash_is_locked = sst26_is_locked;
2484 	}
2485 
2486 	/* sst nor chips use AAI word program */
2487 	if (info->flags & SST_WRITE)
2488 		mtd->_write = sst_write;
2489 	else
2490 #endif
2491 		mtd->_write = spi_nor_write;
2492 
2493 	if (info->flags & USE_FSR)
2494 		nor->flags |= SNOR_F_USE_FSR;
2495 	if (info->flags & SPI_NOR_HAS_TB)
2496 		nor->flags |= SNOR_F_HAS_SR_TB;
2497 	if (info->flags & NO_CHIP_ERASE)
2498 		nor->flags |= SNOR_F_NO_OP_CHIP_ERASE;
2499 	if (info->flags & USE_CLSR)
2500 		nor->flags |= SNOR_F_USE_CLSR;
2501 
2502 	if (info->flags & SPI_NOR_NO_ERASE)
2503 		mtd->flags |= MTD_NO_ERASE;
2504 
2505 	nor->page_size = params.page_size;
2506 	mtd->writebufsize = nor->page_size;
2507 
2508 	/* Some devices cannot do fast-read, no matter what DT tells us */
2509 	if ((info->flags & SPI_NOR_NO_FR) || (spi->mode & SPI_RX_SLOW))
2510 		params.hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
2511 
2512 	/*
2513 	 * Configure the SPI memory:
2514 	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
2515 	 * - set the number of dummy cycles (mode cycles + wait states).
2516 	 * - set the SPI protocols for register and memory accesses.
2517 	 * - set the Quad Enable bit if needed (required by SPI x-y-4 protos).
2518 	 */
2519 	ret = spi_nor_setup(nor, info, &params, &hwcaps);
2520 	if (ret)
2521 		return ret;
2522 
2523 	if (nor->addr_width) {
2524 		/* already configured from SFDP */
2525 	} else if (info->addr_width) {
2526 		nor->addr_width = info->addr_width;
2527 	} else if (mtd->size > SZ_16M) {
2528 #ifndef CONFIG_SPI_FLASH_BAR
2529 		/* enable 4-byte addressing if the device exceeds 16MiB */
2530 		nor->addr_width = 4;
2531 		if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
2532 		    info->flags & SPI_NOR_4B_OPCODES)
2533 			spi_nor_set_4byte_opcodes(nor, info);
2534 #else
2535 	/* Configure the BAR - discover bank cmds and read current bank */
2536 	nor->addr_width = 3;
2537 	ret = read_bar(nor, info);
2538 	if (ret < 0)
2539 		return ret;
2540 #endif
2541 	} else {
2542 		nor->addr_width = 3;
2543 	}
2544 
2545 	if (nor->addr_width > SPI_NOR_MAX_ADDR_WIDTH) {
2546 		dev_dbg(dev, "address width is too large: %u\n",
2547 			nor->addr_width);
2548 		return -EINVAL;
2549 	}
2550 
2551 	/* Send all the required SPI flash commands to initialize device */
2552 	nor->info = info;
2553 	ret = spi_nor_init(nor);
2554 	if (ret)
2555 		return ret;
2556 
2557 	nor->name = mtd->name;
2558 	nor->size = mtd->size;
2559 	nor->erase_size = mtd->erasesize;
2560 	nor->sector_size = mtd->erasesize;
2561 
2562 #ifndef CONFIG_SPL_BUILD
2563 	printf("SF: Detected %s with page size ", nor->name);
2564 	print_size(nor->page_size, ", erase size ");
2565 	print_size(nor->erase_size, ", total ");
2566 	print_size(nor->size, "");
2567 	puts("\n");
2568 #endif
2569 
2570 	return 0;
2571 }
2572 
2573 /* U-Boot specific functions, need to extend MTD to support these */
2574 int spi_flash_cmd_get_sw_write_prot(struct spi_nor *nor)
2575 {
2576 	int sr = read_sr(nor);
2577 
2578 	if (sr < 0)
2579 		return sr;
2580 
2581 	return (sr >> 2) & 7;
2582 }
2583