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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * SPI Flash Core
4  *
5  * Copyright (C) 2015 Jagan Teki <jteki@openedev.com>
6  * Copyright (C) 2013 Jagannadha Sutradharudu Teki, Xilinx Inc.
7  * Copyright (C) 2010 Reinhard Meyer, EMK Elektronik
8  * Copyright (C) 2008 Atmel Corporation
9  */
10 
11 #include <common.h>
12 #include <errno.h>
13 #include <malloc.h>
14 #include <mapmem.h>
15 #include <spi.h>
16 #include <spi_flash.h>
17 #include <linux/log2.h>
18 #include <linux/sizes.h>
19 #include <dma.h>
20 
21 #include "sf_internal.h"
22 
spi_flash_addr(u32 addr,u8 * cmd)23 static void spi_flash_addr(u32 addr, u8 *cmd)
24 {
25 	/* cmd[0] is actual command */
26 	cmd[1] = addr >> 16;
27 	cmd[2] = addr >> 8;
28 	cmd[3] = addr >> 0;
29 }
30 
read_sr(struct spi_flash * flash,u8 * rs)31 static int read_sr(struct spi_flash *flash, u8 *rs)
32 {
33 	int ret;
34 	u8 cmd;
35 
36 	cmd = CMD_READ_STATUS;
37 	ret = spi_flash_read_common(flash, &cmd, 1, rs, 1);
38 	if (ret < 0) {
39 		debug("SF: fail to read status register\n");
40 		return ret;
41 	}
42 
43 	return 0;
44 }
45 
read_fsr(struct spi_flash * flash,u8 * fsr)46 static int read_fsr(struct spi_flash *flash, u8 *fsr)
47 {
48 	int ret;
49 	const u8 cmd = CMD_FLAG_STATUS;
50 
51 	ret = spi_flash_read_common(flash, &cmd, 1, fsr, 1);
52 	if (ret < 0) {
53 		debug("SF: fail to read flag status register\n");
54 		return ret;
55 	}
56 
57 	return 0;
58 }
59 
write_sr(struct spi_flash * flash,u8 ws)60 static int write_sr(struct spi_flash *flash, u8 ws)
61 {
62 	u8 cmd;
63 	int ret;
64 
65 	cmd = CMD_WRITE_STATUS;
66 	ret = spi_flash_write_common(flash, &cmd, 1, &ws, 1);
67 	if (ret < 0) {
68 		debug("SF: fail to write status register\n");
69 		return ret;
70 	}
71 
72 	return 0;
73 }
74 
75 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
read_cr(struct spi_flash * flash,u8 * rc)76 static int read_cr(struct spi_flash *flash, u8 *rc)
77 {
78 	int ret;
79 	u8 cmd;
80 
81 	cmd = CMD_READ_CONFIG;
82 	ret = spi_flash_read_common(flash, &cmd, 1, rc, 1);
83 	if (ret < 0) {
84 		debug("SF: fail to read config register\n");
85 		return ret;
86 	}
87 
88 	return 0;
89 }
90 
write_cr(struct spi_flash * flash,u8 wc)91 static int write_cr(struct spi_flash *flash, u8 wc)
92 {
93 	u8 data[2];
94 	u8 cmd;
95 	int ret;
96 
97 	ret = read_sr(flash, &data[0]);
98 	if (ret < 0)
99 		return ret;
100 
101 	cmd = CMD_WRITE_STATUS;
102 	data[1] = wc;
103 	ret = spi_flash_write_common(flash, &cmd, 1, &data, 2);
104 	if (ret) {
105 		debug("SF: fail to write config register\n");
106 		return ret;
107 	}
108 
109 	return 0;
110 }
111 #endif
112 
113 #ifdef CONFIG_SPI_FLASH_BAR
114 /*
115  * This "clean_bar" is necessary in a situation when one was accessing
116  * spi flash memory > 16 MiB by using Bank Address Register's BA24 bit.
117  *
118  * After it the BA24 bit shall be cleared to allow access to correct
119  * memory region after SW reset (by calling "reset" command).
120  *
121  * Otherwise, the BA24 bit may be left set and then after reset, the
122  * ROM would read/write/erase SPL from 16 MiB * bank_sel address.
123  */
clean_bar(struct spi_flash * flash)124 static int clean_bar(struct spi_flash *flash)
125 {
126 	u8 cmd, bank_sel = 0;
127 
128 	if (flash->bank_curr == 0)
129 		return 0;
130 	cmd = flash->bank_write_cmd;
131 	flash->bank_curr = 0;
132 
133 	return spi_flash_write_common(flash, &cmd, 1, &bank_sel, 1);
134 }
135 
write_bar(struct spi_flash * flash,u32 offset)136 static int write_bar(struct spi_flash *flash, u32 offset)
137 {
138 	u8 cmd, bank_sel;
139 	int ret;
140 
141 	bank_sel = offset / (SPI_FLASH_16MB_BOUN << flash->shift);
142 	if (bank_sel == flash->bank_curr)
143 		goto bar_end;
144 
145 	cmd = flash->bank_write_cmd;
146 	ret = spi_flash_write_common(flash, &cmd, 1, &bank_sel, 1);
147 	if (ret < 0) {
148 		debug("SF: fail to write bank register\n");
149 		return ret;
150 	}
151 
152 bar_end:
153 	flash->bank_curr = bank_sel;
154 	return flash->bank_curr;
155 }
156 
read_bar(struct spi_flash * flash,const struct spi_flash_info * info)157 static int read_bar(struct spi_flash *flash, const struct spi_flash_info *info)
158 {
159 	u8 curr_bank = 0;
160 	int ret;
161 
162 	if (flash->size <= SPI_FLASH_16MB_BOUN)
163 		goto bar_end;
164 
165 	switch (JEDEC_MFR(info)) {
166 	case SPI_FLASH_CFI_MFR_SPANSION:
167 		flash->bank_read_cmd = CMD_BANKADDR_BRRD;
168 		flash->bank_write_cmd = CMD_BANKADDR_BRWR;
169 		break;
170 	default:
171 		flash->bank_read_cmd = CMD_EXTNADDR_RDEAR;
172 		flash->bank_write_cmd = CMD_EXTNADDR_WREAR;
173 	}
174 
175 	ret = spi_flash_read_common(flash, &flash->bank_read_cmd, 1,
176 				    &curr_bank, 1);
177 	if (ret) {
178 		debug("SF: fail to read bank addr register\n");
179 		return ret;
180 	}
181 
182 bar_end:
183 	flash->bank_curr = curr_bank;
184 	return 0;
185 }
186 #endif
187 
188 #ifdef CONFIG_SF_DUAL_FLASH
spi_flash_dual(struct spi_flash * flash,u32 * addr)189 static void spi_flash_dual(struct spi_flash *flash, u32 *addr)
190 {
191 	switch (flash->dual_flash) {
192 	case SF_DUAL_STACKED_FLASH:
193 		if (*addr >= (flash->size >> 1)) {
194 			*addr -= flash->size >> 1;
195 			flash->flags |= SNOR_F_USE_UPAGE;
196 		} else {
197 			flash->flags &= ~SNOR_F_USE_UPAGE;
198 		}
199 		break;
200 	case SF_DUAL_PARALLEL_FLASH:
201 		*addr >>= flash->shift;
202 		break;
203 	default:
204 		debug("SF: Unsupported dual_flash=%d\n", flash->dual_flash);
205 		break;
206 	}
207 }
208 #endif
209 
spi_flash_sr_ready(struct spi_flash * flash)210 static int spi_flash_sr_ready(struct spi_flash *flash)
211 {
212 	u8 sr;
213 	int ret;
214 
215 	ret = read_sr(flash, &sr);
216 	if (ret < 0)
217 		return ret;
218 
219 	return !(sr & STATUS_WIP);
220 }
221 
spi_flash_fsr_ready(struct spi_flash * flash)222 static int spi_flash_fsr_ready(struct spi_flash *flash)
223 {
224 	u8 fsr;
225 	int ret;
226 
227 	ret = read_fsr(flash, &fsr);
228 	if (ret < 0)
229 		return ret;
230 
231 	return fsr & STATUS_PEC;
232 }
233 
spi_flash_ready(struct spi_flash * flash)234 static int spi_flash_ready(struct spi_flash *flash)
235 {
236 	int sr, fsr;
237 
238 	sr = spi_flash_sr_ready(flash);
239 	if (sr < 0)
240 		return sr;
241 
242 	fsr = 1;
243 	if (flash->flags & SNOR_F_USE_FSR) {
244 		fsr = spi_flash_fsr_ready(flash);
245 		if (fsr < 0)
246 			return fsr;
247 	}
248 
249 	return sr && fsr;
250 }
251 
spi_flash_wait_till_ready(struct spi_flash * flash,unsigned long timeout)252 static int spi_flash_wait_till_ready(struct spi_flash *flash,
253 				     unsigned long timeout)
254 {
255 	unsigned long timebase;
256 	int ret;
257 
258 	timebase = get_timer(0);
259 
260 	while (get_timer(timebase) < timeout) {
261 		ret = spi_flash_ready(flash);
262 		if (ret < 0)
263 			return ret;
264 		if (ret)
265 			return 0;
266 	}
267 
268 	printf("SF: Timeout!\n");
269 
270 	return -ETIMEDOUT;
271 }
272 
spi_flash_write_common(struct spi_flash * flash,const u8 * cmd,size_t cmd_len,const void * buf,size_t buf_len)273 int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
274 		size_t cmd_len, const void *buf, size_t buf_len)
275 {
276 	struct spi_slave *spi = flash->spi;
277 	unsigned long timeout = SPI_FLASH_PROG_TIMEOUT;
278 	int ret;
279 
280 	if (buf == NULL)
281 		timeout = SPI_FLASH_PAGE_ERASE_TIMEOUT;
282 
283 	ret = spi_claim_bus(spi);
284 	if (ret) {
285 		debug("SF: unable to claim SPI bus\n");
286 		return ret;
287 	}
288 
289 	ret = spi_flash_cmd_write_enable(flash);
290 	if (ret < 0) {
291 		debug("SF: enabling write failed\n");
292 		return ret;
293 	}
294 
295 	ret = spi_flash_cmd_write(spi, cmd, cmd_len, buf, buf_len);
296 	if (ret < 0) {
297 		debug("SF: write cmd failed\n");
298 		return ret;
299 	}
300 
301 	ret = spi_flash_wait_till_ready(flash, timeout);
302 	if (ret < 0) {
303 		debug("SF: write %s timed out\n",
304 		      timeout == SPI_FLASH_PROG_TIMEOUT ?
305 			"program" : "page erase");
306 		return ret;
307 	}
308 
309 	spi_release_bus(spi);
310 
311 	return ret;
312 }
313 
spi_flash_cmd_erase_ops(struct spi_flash * flash,u32 offset,size_t len)314 int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
315 {
316 	u32 erase_size, erase_addr;
317 	u8 cmd[SPI_FLASH_CMD_LEN];
318 	int ret = -1;
319 
320 	erase_size = flash->erase_size;
321 	if (offset % erase_size || len % erase_size) {
322 		printf("SF: Erase offset/length not multiple of erase size\n");
323 		return -1;
324 	}
325 
326 	if (flash->flash_is_locked) {
327 		if (flash->flash_is_locked(flash, offset, len) > 0) {
328 			printf("offset 0x%x is protected and cannot be erased\n",
329 			       offset);
330 			return -EINVAL;
331 		}
332 	}
333 
334 	cmd[0] = flash->erase_cmd;
335 	while (len) {
336 		erase_addr = offset;
337 
338 #ifdef CONFIG_SF_DUAL_FLASH
339 		if (flash->dual_flash > SF_SINGLE_FLASH)
340 			spi_flash_dual(flash, &erase_addr);
341 #endif
342 #ifdef CONFIG_SPI_FLASH_BAR
343 		ret = write_bar(flash, erase_addr);
344 		if (ret < 0)
345 			return ret;
346 #endif
347 		spi_flash_addr(erase_addr, cmd);
348 
349 		debug("SF: erase %2x %2x %2x %2x (%x)\n", cmd[0], cmd[1],
350 		      cmd[2], cmd[3], erase_addr);
351 
352 		ret = spi_flash_write_common(flash, cmd, sizeof(cmd), NULL, 0);
353 		if (ret < 0) {
354 			debug("SF: erase failed\n");
355 			break;
356 		}
357 
358 		offset += erase_size;
359 		len -= erase_size;
360 	}
361 
362 #ifdef CONFIG_SPI_FLASH_BAR
363 	ret = clean_bar(flash);
364 #endif
365 
366 	return ret;
367 }
368 
spi_flash_cmd_write_ops(struct spi_flash * flash,u32 offset,size_t len,const void * buf)369 int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
370 		size_t len, const void *buf)
371 {
372 	struct spi_slave *spi = flash->spi;
373 	unsigned long byte_addr, page_size;
374 	u32 write_addr;
375 	size_t chunk_len, actual;
376 	u8 cmd[SPI_FLASH_CMD_LEN];
377 	int ret = -1;
378 
379 	page_size = flash->page_size;
380 
381 	if (flash->flash_is_locked) {
382 		if (flash->flash_is_locked(flash, offset, len) > 0) {
383 			printf("offset 0x%x is protected and cannot be written\n",
384 			       offset);
385 			return -EINVAL;
386 		}
387 	}
388 
389 	cmd[0] = flash->write_cmd;
390 	for (actual = 0; actual < len; actual += chunk_len) {
391 		write_addr = offset;
392 
393 #ifdef CONFIG_SF_DUAL_FLASH
394 		if (flash->dual_flash > SF_SINGLE_FLASH)
395 			spi_flash_dual(flash, &write_addr);
396 #endif
397 #ifdef CONFIG_SPI_FLASH_BAR
398 		ret = write_bar(flash, write_addr);
399 		if (ret < 0)
400 			return ret;
401 #endif
402 		byte_addr = offset % page_size;
403 		chunk_len = min(len - actual, (size_t)(page_size - byte_addr));
404 
405 		if (spi->max_write_size)
406 			chunk_len = min(chunk_len,
407 					spi->max_write_size - sizeof(cmd));
408 
409 		spi_flash_addr(write_addr, cmd);
410 
411 		debug("SF: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zu\n",
412 		      buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
413 
414 		ret = spi_flash_write_common(flash, cmd, sizeof(cmd),
415 					buf + actual, chunk_len);
416 		if (ret < 0) {
417 			debug("SF: write failed\n");
418 			break;
419 		}
420 
421 		offset += chunk_len;
422 	}
423 
424 #ifdef CONFIG_SPI_FLASH_BAR
425 	ret = clean_bar(flash);
426 #endif
427 
428 	return ret;
429 }
430 
spi_flash_read_common(struct spi_flash * flash,const u8 * cmd,size_t cmd_len,void * data,size_t data_len)431 int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
432 		size_t cmd_len, void *data, size_t data_len)
433 {
434 	struct spi_slave *spi = flash->spi;
435 	int ret;
436 
437 	ret = spi_claim_bus(spi);
438 	if (ret) {
439 		debug("SF: unable to claim SPI bus\n");
440 		return ret;
441 	}
442 
443 	ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len);
444 	if (ret < 0) {
445 		debug("SF: read cmd failed\n");
446 		return ret;
447 	}
448 
449 	spi_release_bus(spi);
450 
451 	return ret;
452 }
453 
454 /*
455  * TODO: remove the weak after all the other spi_flash_copy_mmap
456  * implementations removed from drivers
457  */
spi_flash_copy_mmap(void * data,void * offset,size_t len)458 void __weak spi_flash_copy_mmap(void *data, void *offset, size_t len)
459 {
460 #ifdef CONFIG_DMA
461 	if (!dma_memcpy(data, offset, len))
462 		return;
463 #endif
464 	memcpy(data, offset, len);
465 }
466 
spi_flash_cmd_read_ops(struct spi_flash * flash,u32 offset,size_t len,void * data)467 int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
468 		size_t len, void *data)
469 {
470 	struct spi_slave *spi = flash->spi;
471 	u8 *cmd, cmdsz;
472 	u32 remain_len, read_len, read_addr;
473 	int bank_sel = 0;
474 	int ret = -1;
475 
476 	/* Handle memory-mapped SPI */
477 	if (flash->memory_map) {
478 		ret = spi_claim_bus(spi);
479 		if (ret) {
480 			debug("SF: unable to claim SPI bus\n");
481 			return ret;
482 		}
483 		spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP);
484 		spi_flash_copy_mmap(data, flash->memory_map + offset, len);
485 		spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP_END);
486 		spi_release_bus(spi);
487 		return 0;
488 	}
489 
490 	cmdsz = SPI_FLASH_CMD_LEN + flash->dummy_byte;
491 	cmd = calloc(1, cmdsz);
492 	if (!cmd) {
493 		debug("SF: Failed to allocate cmd\n");
494 		return -ENOMEM;
495 	}
496 
497 	cmd[0] = flash->read_cmd;
498 	while (len) {
499 		read_addr = offset;
500 
501 #ifdef CONFIG_SF_DUAL_FLASH
502 		if (flash->dual_flash > SF_SINGLE_FLASH)
503 			spi_flash_dual(flash, &read_addr);
504 #endif
505 #ifdef CONFIG_SPI_FLASH_BAR
506 		ret = write_bar(flash, read_addr);
507 		if (ret < 0)
508 			return ret;
509 		bank_sel = flash->bank_curr;
510 #endif
511 		remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
512 				(bank_sel + 1)) - offset;
513 		if (len < remain_len)
514 			read_len = len;
515 		else
516 			read_len = remain_len;
517 
518 		if (spi->max_read_size)
519 			read_len = min(read_len, spi->max_read_size);
520 
521 		spi_flash_addr(read_addr, cmd);
522 
523 		ret = spi_flash_read_common(flash, cmd, cmdsz, data, read_len);
524 		if (ret < 0) {
525 			debug("SF: read failed\n");
526 			break;
527 		}
528 
529 		offset += read_len;
530 		len -= read_len;
531 		data += read_len;
532 	}
533 
534 #ifdef CONFIG_SPI_FLASH_BAR
535 	ret = clean_bar(flash);
536 #endif
537 
538 	free(cmd);
539 	return ret;
540 }
541 
542 #ifdef CONFIG_SPI_FLASH_SST
sst26_process_bpr(u32 bpr_size,u8 * cmd,u32 bit,enum lock_ctl ctl)543 static bool sst26_process_bpr(u32 bpr_size, u8 *cmd, u32 bit, enum lock_ctl ctl)
544 {
545 	switch (ctl) {
546 		case SST26_CTL_LOCK:
547 			cmd[bpr_size - (bit / 8) - 1] |= BIT(bit % 8);
548 			break;
549 		case SST26_CTL_UNLOCK:
550 			cmd[bpr_size - (bit / 8) - 1] &= ~BIT(bit % 8);
551 			break;
552 		case SST26_CTL_CHECK:
553 			return !!(cmd[bpr_size - (bit / 8) - 1] & BIT(bit % 8));
554 	}
555 
556 	return false;
557 }
558 
559 /*
560  * sst26wf016/sst26wf032/sst26wf064 have next block protection:
561  * 4x   - 8  KByte blocks - read & write protection bits - upper addresses
562  * 1x   - 32 KByte blocks - write protection bits
563  * rest - 64 KByte blocks - write protection bits
564  * 1x   - 32 KByte blocks - write protection bits
565  * 4x   - 8  KByte blocks - read & write protection bits - lower addresses
566  *
567  * We'll support only per 64k lock/unlock so lower and upper 64 KByte region
568  * will be treated as single block.
569  */
570 
571 /*
572  * Lock, unlock or check lock status of the flash region of the flash (depending
573  * on the lock_ctl value)
574  */
sst26_lock_ctl(struct spi_flash * flash,u32 ofs,size_t len,enum lock_ctl ctl)575 static int sst26_lock_ctl(struct spi_flash *flash, u32 ofs, size_t len, enum lock_ctl ctl)
576 {
577 	u32 i, bpr_ptr, rptr_64k, lptr_64k, bpr_size;
578 	bool lower_64k = false, upper_64k = false;
579 	u8 cmd, bpr_buff[SST26_MAX_BPR_REG_LEN] = {};
580 	int ret;
581 
582 	/* Check length and offset for 64k alignment */
583 	if ((ofs & (SZ_64K - 1)) || (len & (SZ_64K - 1)))
584 		return -EINVAL;
585 
586 	if (ofs + len > flash->size)
587 		return -EINVAL;
588 
589 	/* SST26 family has only 16 Mbit, 32 Mbit and 64 Mbit IC */
590 	if (flash->size != SZ_2M &&
591 	    flash->size != SZ_4M &&
592 	    flash->size != SZ_8M)
593 		return -EINVAL;
594 
595 	bpr_size = 2 + (flash->size / SZ_64K / 8);
596 
597 	cmd = SST26_CMD_READ_BPR;
598 	ret = spi_flash_read_common(flash, &cmd, 1, bpr_buff, bpr_size);
599 	if (ret < 0) {
600 		printf("SF: fail to read block-protection register\n");
601 		return ret;
602 	}
603 
604 	rptr_64k = min_t(u32, ofs + len , flash->size - SST26_BOUND_REG_SIZE);
605 	lptr_64k = max_t(u32, ofs, SST26_BOUND_REG_SIZE);
606 
607 	upper_64k = ((ofs + len) > (flash->size - SST26_BOUND_REG_SIZE));
608 	lower_64k = (ofs < SST26_BOUND_REG_SIZE);
609 
610 	/* Lower bits in block-protection register are about 64k region */
611 	bpr_ptr = lptr_64k / SZ_64K - 1;
612 
613 	/* Process 64K blocks region */
614 	while (lptr_64k < rptr_64k) {
615 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
616 			return EACCES;
617 
618 		bpr_ptr++;
619 		lptr_64k += SZ_64K;
620 	}
621 
622 	/* 32K and 8K region bits in BPR are after 64k region bits */
623 	bpr_ptr = (flash->size - 2 * SST26_BOUND_REG_SIZE) / SZ_64K;
624 
625 	/* Process lower 32K block region */
626 	if (lower_64k)
627 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
628 			return EACCES;
629 
630 	bpr_ptr++;
631 
632 	/* Process upper 32K block region */
633 	if (upper_64k)
634 		if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
635 			return EACCES;
636 
637 	bpr_ptr++;
638 
639 	/* Process lower 8K block regions */
640 	for (i = 0; i < SST26_BPR_8K_NUM; i++) {
641 		if (lower_64k)
642 			if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
643 				return EACCES;
644 
645 		/* In 8K area BPR has both read and write protection bits */
646 		bpr_ptr += 2;
647 	}
648 
649 	/* Process upper 8K block regions */
650 	for (i = 0; i < SST26_BPR_8K_NUM; i++) {
651 		if (upper_64k)
652 			if (sst26_process_bpr(bpr_size, bpr_buff, bpr_ptr, ctl))
653 				return EACCES;
654 
655 		/* In 8K area BPR has both read and write protection bits */
656 		bpr_ptr += 2;
657 	}
658 
659 	/* If we check region status we don't need to write BPR back */
660 	if (ctl == SST26_CTL_CHECK)
661 		return 0;
662 
663 	cmd = SST26_CMD_WRITE_BPR;
664 	ret = spi_flash_write_common(flash, &cmd, 1, bpr_buff, bpr_size);
665 	if (ret < 0) {
666 		printf("SF: fail to write block-protection register\n");
667 		return ret;
668 	}
669 
670 	return 0;
671 }
672 
sst26_unlock(struct spi_flash * flash,u32 ofs,size_t len)673 static int sst26_unlock(struct spi_flash *flash, u32 ofs, size_t len)
674 {
675 	return sst26_lock_ctl(flash, ofs, len, SST26_CTL_UNLOCK);
676 }
677 
sst26_lock(struct spi_flash * flash,u32 ofs,size_t len)678 static int sst26_lock(struct spi_flash *flash, u32 ofs, size_t len)
679 {
680 	return sst26_lock_ctl(flash, ofs, len, SST26_CTL_LOCK);
681 }
682 
683 /*
684  * Returns EACCES (positive value) if region is locked, 0 if region is unlocked,
685  * and negative on errors.
686  */
sst26_is_locked(struct spi_flash * flash,u32 ofs,size_t len)687 static int sst26_is_locked(struct spi_flash *flash, u32 ofs, size_t len)
688 {
689 	/*
690 	 * is_locked function is used for check before reading or erasing flash
691 	 * region, so offset and length might be not 64k allighned, so adjust
692 	 * them to be 64k allighned as sst26_lock_ctl works only with 64k
693 	 * allighned regions.
694 	 */
695 	ofs -= ofs & (SZ_64K - 1);
696 	len = len & (SZ_64K - 1) ? (len & ~(SZ_64K - 1)) + SZ_64K : len;
697 
698 	return sst26_lock_ctl(flash, ofs, len, SST26_CTL_CHECK);
699 }
700 
sst_byte_write(struct spi_flash * flash,u32 offset,const void * buf)701 static int sst_byte_write(struct spi_flash *flash, u32 offset, const void *buf)
702 {
703 	struct spi_slave *spi = flash->spi;
704 	int ret;
705 	u8 cmd[4] = {
706 		CMD_SST_BP,
707 		offset >> 16,
708 		offset >> 8,
709 		offset,
710 	};
711 
712 	debug("BP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
713 	      spi_w8r8(spi, CMD_READ_STATUS), buf, cmd[0], offset);
714 
715 	ret = spi_flash_cmd_write_enable(flash);
716 	if (ret)
717 		return ret;
718 
719 	ret = spi_flash_cmd_write(spi, cmd, sizeof(cmd), buf, 1);
720 	if (ret)
721 		return ret;
722 
723 	return spi_flash_wait_till_ready(flash, SPI_FLASH_PROG_TIMEOUT);
724 }
725 
sst_write_wp(struct spi_flash * flash,u32 offset,size_t len,const void * buf)726 int sst_write_wp(struct spi_flash *flash, u32 offset, size_t len,
727 		const void *buf)
728 {
729 	struct spi_slave *spi = flash->spi;
730 	size_t actual, cmd_len;
731 	int ret;
732 	u8 cmd[4];
733 
734 	ret = spi_claim_bus(spi);
735 	if (ret) {
736 		debug("SF: Unable to claim SPI bus\n");
737 		return ret;
738 	}
739 
740 	/* If the data is not word aligned, write out leading single byte */
741 	actual = offset % 2;
742 	if (actual) {
743 		ret = sst_byte_write(flash, offset, buf);
744 		if (ret)
745 			goto done;
746 	}
747 	offset += actual;
748 
749 	ret = spi_flash_cmd_write_enable(flash);
750 	if (ret)
751 		goto done;
752 
753 	cmd_len = 4;
754 	cmd[0] = CMD_SST_AAI_WP;
755 	cmd[1] = offset >> 16;
756 	cmd[2] = offset >> 8;
757 	cmd[3] = offset;
758 
759 	for (; actual < len - 1; actual += 2) {
760 		debug("WP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
761 		      spi_w8r8(spi, CMD_READ_STATUS), buf + actual,
762 		      cmd[0], offset);
763 
764 		ret = spi_flash_cmd_write(spi, cmd, cmd_len,
765 					buf + actual, 2);
766 		if (ret) {
767 			debug("SF: sst word program failed\n");
768 			break;
769 		}
770 
771 		ret = spi_flash_wait_till_ready(flash, SPI_FLASH_PROG_TIMEOUT);
772 		if (ret)
773 			break;
774 
775 		cmd_len = 1;
776 		offset += 2;
777 	}
778 
779 	if (!ret)
780 		ret = spi_flash_cmd_write_disable(flash);
781 
782 	/* If there is a single trailing byte, write it out */
783 	if (!ret && actual != len)
784 		ret = sst_byte_write(flash, offset, buf + actual);
785 
786  done:
787 	debug("SF: sst: program %s %zu bytes @ 0x%zx\n",
788 	      ret ? "failure" : "success", len, offset - actual);
789 
790 	spi_release_bus(spi);
791 	return ret;
792 }
793 
sst_write_bp(struct spi_flash * flash,u32 offset,size_t len,const void * buf)794 int sst_write_bp(struct spi_flash *flash, u32 offset, size_t len,
795 		const void *buf)
796 {
797 	struct spi_slave *spi = flash->spi;
798 	size_t actual;
799 	int ret;
800 
801 	ret = spi_claim_bus(spi);
802 	if (ret) {
803 		debug("SF: Unable to claim SPI bus\n");
804 		return ret;
805 	}
806 
807 	for (actual = 0; actual < len; actual++) {
808 		ret = sst_byte_write(flash, offset, buf + actual);
809 		if (ret) {
810 			debug("SF: sst byte program failed\n");
811 			break;
812 		}
813 		offset++;
814 	}
815 
816 	if (!ret)
817 		ret = spi_flash_cmd_write_disable(flash);
818 
819 	debug("SF: sst: program %s %zu bytes @ 0x%zx\n",
820 	      ret ? "failure" : "success", len, offset - actual);
821 
822 	spi_release_bus(spi);
823 	return ret;
824 }
825 #endif
826 
827 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
stm_get_locked_range(struct spi_flash * flash,u8 sr,loff_t * ofs,u64 * len)828 static void stm_get_locked_range(struct spi_flash *flash, u8 sr, loff_t *ofs,
829 				 u64 *len)
830 {
831 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
832 	int shift = ffs(mask) - 1;
833 	int pow;
834 
835 	if (!(sr & mask)) {
836 		/* No protection */
837 		*ofs = 0;
838 		*len = 0;
839 	} else {
840 		pow = ((sr & mask) ^ mask) >> shift;
841 		*len = flash->size >> pow;
842 		*ofs = flash->size - *len;
843 	}
844 }
845 
846 /*
847  * Return 1 if the entire region is locked, 0 otherwise
848  */
stm_is_locked_sr(struct spi_flash * flash,loff_t ofs,u64 len,u8 sr)849 static int stm_is_locked_sr(struct spi_flash *flash, loff_t ofs, u64 len,
850 			    u8 sr)
851 {
852 	loff_t lock_offs;
853 	u64 lock_len;
854 
855 	stm_get_locked_range(flash, sr, &lock_offs, &lock_len);
856 
857 	return (ofs + len <= lock_offs + lock_len) && (ofs >= lock_offs);
858 }
859 
860 /*
861  * Check if a region of the flash is (completely) locked. See stm_lock() for
862  * more info.
863  *
864  * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
865  * negative on errors.
866  */
stm_is_locked(struct spi_flash * flash,u32 ofs,size_t len)867 int stm_is_locked(struct spi_flash *flash, u32 ofs, size_t len)
868 {
869 	int status;
870 	u8 sr;
871 
872 	status = read_sr(flash, &sr);
873 	if (status < 0)
874 		return status;
875 
876 	return stm_is_locked_sr(flash, ofs, len, sr);
877 }
878 
879 /*
880  * Lock a region of the flash. Compatible with ST Micro and similar flash.
881  * Supports only the block protection bits BP{0,1,2} in the status register
882  * (SR). Does not support these features found in newer SR bitfields:
883  *   - TB: top/bottom protect - only handle TB=0 (top protect)
884  *   - SEC: sector/block protect - only handle SEC=0 (block protect)
885  *   - CMP: complement protect - only support CMP=0 (range is not complemented)
886  *
887  * Sample table portion for 8MB flash (Winbond w25q64fw):
888  *
889  *   SEC  |  TB   |  BP2  |  BP1  |  BP0  |  Prot Length  | Protected Portion
890  *  --------------------------------------------------------------------------
891  *    X   |   X   |   0   |   0   |   0   |  NONE         | NONE
892  *    0   |   0   |   0   |   0   |   1   |  128 KB       | Upper 1/64
893  *    0   |   0   |   0   |   1   |   0   |  256 KB       | Upper 1/32
894  *    0   |   0   |   0   |   1   |   1   |  512 KB       | Upper 1/16
895  *    0   |   0   |   1   |   0   |   0   |  1 MB         | Upper 1/8
896  *    0   |   0   |   1   |   0   |   1   |  2 MB         | Upper 1/4
897  *    0   |   0   |   1   |   1   |   0   |  4 MB         | Upper 1/2
898  *    X   |   X   |   1   |   1   |   1   |  8 MB         | ALL
899  *
900  * Returns negative on errors, 0 on success.
901  */
stm_lock(struct spi_flash * flash,u32 ofs,size_t len)902 int stm_lock(struct spi_flash *flash, u32 ofs, size_t len)
903 {
904 	u8 status_old, status_new;
905 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
906 	u8 shift = ffs(mask) - 1, pow, val;
907 	int ret;
908 
909 	ret = read_sr(flash, &status_old);
910 	if (ret < 0)
911 		return ret;
912 
913 	/* SPI NOR always locks to the end */
914 	if (ofs + len != flash->size) {
915 		/* Does combined region extend to end? */
916 		if (!stm_is_locked_sr(flash, ofs + len, flash->size - ofs - len,
917 				      status_old))
918 			return -EINVAL;
919 		len = flash->size - ofs;
920 	}
921 
922 	/*
923 	 * Need smallest pow such that:
924 	 *
925 	 *   1 / (2^pow) <= (len / size)
926 	 *
927 	 * so (assuming power-of-2 size) we do:
928 	 *
929 	 *   pow = ceil(log2(size / len)) = log2(size) - floor(log2(len))
930 	 */
931 	pow = ilog2(flash->size) - ilog2(len);
932 	val = mask - (pow << shift);
933 	if (val & ~mask)
934 		return -EINVAL;
935 
936 	/* Don't "lock" with no region! */
937 	if (!(val & mask))
938 		return -EINVAL;
939 
940 	status_new = (status_old & ~mask) | val;
941 
942 	/* Only modify protection if it will not unlock other areas */
943 	if ((status_new & mask) <= (status_old & mask))
944 		return -EINVAL;
945 
946 	write_sr(flash, status_new);
947 
948 	return 0;
949 }
950 
951 /*
952  * Unlock a region of the flash. See stm_lock() for more info
953  *
954  * Returns negative on errors, 0 on success.
955  */
stm_unlock(struct spi_flash * flash,u32 ofs,size_t len)956 int stm_unlock(struct spi_flash *flash, u32 ofs, size_t len)
957 {
958 	uint8_t status_old, status_new;
959 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
960 	u8 shift = ffs(mask) - 1, pow, val;
961 	int ret;
962 
963 	ret = read_sr(flash, &status_old);
964 	if (ret < 0)
965 		return ret;
966 
967 	/* Cannot unlock; would unlock larger region than requested */
968 	if (stm_is_locked_sr(flash, ofs - flash->erase_size, flash->erase_size,
969 			     status_old))
970 		return -EINVAL;
971 	/*
972 	 * Need largest pow such that:
973 	 *
974 	 *   1 / (2^pow) >= (len / size)
975 	 *
976 	 * so (assuming power-of-2 size) we do:
977 	 *
978 	 *   pow = floor(log2(size / len)) = log2(size) - ceil(log2(len))
979 	 */
980 	pow = ilog2(flash->size) - order_base_2(flash->size - (ofs + len));
981 	if (ofs + len == flash->size) {
982 		val = 0; /* fully unlocked */
983 	} else {
984 		val = mask - (pow << shift);
985 		/* Some power-of-two sizes are not supported */
986 		if (val & ~mask)
987 			return -EINVAL;
988 	}
989 
990 	status_new = (status_old & ~mask) | val;
991 
992 	/* Only modify protection if it will not lock other areas */
993 	if ((status_new & mask) >= (status_old & mask))
994 		return -EINVAL;
995 
996 	write_sr(flash, status_new);
997 
998 	return 0;
999 }
1000 #endif
1001 
1002 
1003 #ifdef CONFIG_SPI_FLASH_MACRONIX
macronix_quad_enable(struct spi_flash * flash)1004 static int macronix_quad_enable(struct spi_flash *flash)
1005 {
1006 	u8 qeb_status;
1007 	int ret;
1008 
1009 	ret = read_sr(flash, &qeb_status);
1010 	if (ret < 0)
1011 		return ret;
1012 
1013 	if (qeb_status & STATUS_QEB_MXIC)
1014 		return 0;
1015 
1016 	ret = write_sr(flash, qeb_status | STATUS_QEB_MXIC);
1017 	if (ret < 0)
1018 		return ret;
1019 
1020 	/* read SR and check it */
1021 	ret = read_sr(flash, &qeb_status);
1022 	if (!(ret >= 0 && (qeb_status & STATUS_QEB_MXIC))) {
1023 		printf("SF: Macronix SR Quad bit not clear\n");
1024 		return -EINVAL;
1025 	}
1026 
1027 	return ret;
1028 }
1029 #endif
1030 
1031 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
spansion_quad_enable(struct spi_flash * flash)1032 static int spansion_quad_enable(struct spi_flash *flash)
1033 {
1034 	u8 qeb_status;
1035 	int ret;
1036 
1037 	ret = read_cr(flash, &qeb_status);
1038 	if (ret < 0)
1039 		return ret;
1040 
1041 	if (qeb_status & STATUS_QEB_WINSPAN)
1042 		return 0;
1043 
1044 	ret = write_cr(flash, qeb_status | STATUS_QEB_WINSPAN);
1045 	if (ret < 0)
1046 		return ret;
1047 
1048 	/* read CR and check it */
1049 	ret = read_cr(flash, &qeb_status);
1050 	if (!(ret >= 0 && (qeb_status & STATUS_QEB_WINSPAN))) {
1051 		printf("SF: Spansion CR Quad bit not clear\n");
1052 		return -EINVAL;
1053 	}
1054 
1055 	return ret;
1056 }
1057 #endif
1058 
spi_flash_read_id(struct spi_flash * flash)1059 static const struct spi_flash_info *spi_flash_read_id(struct spi_flash *flash)
1060 {
1061 	int				tmp;
1062 	u8				id[SPI_FLASH_MAX_ID_LEN];
1063 	const struct spi_flash_info	*info;
1064 
1065 	tmp = spi_flash_cmd(flash->spi, CMD_READ_ID, id, SPI_FLASH_MAX_ID_LEN);
1066 	if (tmp < 0) {
1067 		printf("SF: error %d reading JEDEC ID\n", tmp);
1068 		return ERR_PTR(tmp);
1069 	}
1070 
1071 	info = spi_flash_ids;
1072 	for (; info->name != NULL; info++) {
1073 		if (info->id_len) {
1074 			if (!memcmp(info->id, id, info->id_len))
1075 				return info;
1076 		}
1077 	}
1078 
1079 	printf("SF: unrecognized JEDEC id bytes: %02x, %02x, %02x\n",
1080 	       id[0], id[1], id[2]);
1081 	return ERR_PTR(-ENODEV);
1082 }
1083 
set_quad_mode(struct spi_flash * flash,const struct spi_flash_info * info)1084 static int set_quad_mode(struct spi_flash *flash,
1085 			 const struct spi_flash_info *info)
1086 {
1087 	switch (JEDEC_MFR(info)) {
1088 #ifdef CONFIG_SPI_FLASH_MACRONIX
1089 	case SPI_FLASH_CFI_MFR_MACRONIX:
1090 		return macronix_quad_enable(flash);
1091 #endif
1092 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
1093 	case SPI_FLASH_CFI_MFR_SPANSION:
1094 	case SPI_FLASH_CFI_MFR_WINBOND:
1095 		return spansion_quad_enable(flash);
1096 #endif
1097 #ifdef CONFIG_SPI_FLASH_STMICRO
1098 	case SPI_FLASH_CFI_MFR_STMICRO:
1099 		debug("SF: QEB is volatile for %02x flash\n", JEDEC_MFR(info));
1100 		return 0;
1101 #endif
1102 	default:
1103 		printf("SF: Need set QEB func for %02x flash\n",
1104 		       JEDEC_MFR(info));
1105 		return -1;
1106 	}
1107 }
1108 
1109 #if CONFIG_IS_ENABLED(OF_CONTROL)
spi_flash_decode_fdt(struct spi_flash * flash)1110 int spi_flash_decode_fdt(struct spi_flash *flash)
1111 {
1112 #ifdef CONFIG_DM_SPI_FLASH
1113 	fdt_addr_t addr;
1114 	fdt_size_t size;
1115 
1116 	addr = dev_read_addr_size(flash->dev, "memory-map", &size);
1117 	if (addr == FDT_ADDR_T_NONE) {
1118 		debug("%s: Cannot decode address\n", __func__);
1119 		return 0;
1120 	}
1121 
1122 	if (flash->size > size) {
1123 		debug("%s: Memory map must cover entire device\n", __func__);
1124 		return -1;
1125 	}
1126 	flash->memory_map = map_sysmem(addr, size);
1127 #endif
1128 
1129 	return 0;
1130 }
1131 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
1132 
spi_flash_scan(struct spi_flash * flash)1133 int spi_flash_scan(struct spi_flash *flash)
1134 {
1135 	struct spi_slave *spi = flash->spi;
1136 	const struct spi_flash_info *info = NULL;
1137 	int ret;
1138 
1139 	info = spi_flash_read_id(flash);
1140 	if (IS_ERR_OR_NULL(info))
1141 		return -ENOENT;
1142 
1143 	/*
1144 	 * Flash powers up read-only, so clear BP# bits.
1145 	 *
1146 	 * Note on some flash (like Macronix), QE (quad enable) bit is in the
1147 	 * same status register as BP# bits, and we need preserve its original
1148 	 * value during a reboot cycle as this is required by some platforms
1149 	 * (like Intel ICH SPI controller working under descriptor mode).
1150 	 */
1151 	if (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_ATMEL ||
1152 	   (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_SST) ||
1153 	   (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_MACRONIX)) {
1154 		u8 sr = 0;
1155 
1156 		if (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_MACRONIX) {
1157 			read_sr(flash, &sr);
1158 			sr &= STATUS_QEB_MXIC;
1159 		}
1160 		write_sr(flash, sr);
1161 	}
1162 
1163 	flash->name = info->name;
1164 	flash->memory_map = spi->memory_map;
1165 
1166 	if (info->flags & SST_WR)
1167 		flash->flags |= SNOR_F_SST_WR;
1168 
1169 #ifndef CONFIG_DM_SPI_FLASH
1170 	flash->write = spi_flash_cmd_write_ops;
1171 #if defined(CONFIG_SPI_FLASH_SST)
1172 	if (flash->flags & SNOR_F_SST_WR) {
1173 		if (spi->mode & SPI_TX_BYTE)
1174 			flash->write = sst_write_bp;
1175 		else
1176 			flash->write = sst_write_wp;
1177 	}
1178 #endif
1179 	flash->erase = spi_flash_cmd_erase_ops;
1180 	flash->read = spi_flash_cmd_read_ops;
1181 #endif
1182 
1183 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
1184 	/* NOR protection support for STmicro/Micron chips and similar */
1185 	if (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_STMICRO ||
1186 	    JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_SST) {
1187 		flash->flash_lock = stm_lock;
1188 		flash->flash_unlock = stm_unlock;
1189 		flash->flash_is_locked = stm_is_locked;
1190 	}
1191 #endif
1192 
1193 /* sst26wf series block protection implementation differs from other series */
1194 #if defined(CONFIG_SPI_FLASH_SST)
1195 	if (JEDEC_MFR(info) == SPI_FLASH_CFI_MFR_SST && info->id[1] == 0x26) {
1196 		flash->flash_lock = sst26_lock;
1197 		flash->flash_unlock = sst26_unlock;
1198 		flash->flash_is_locked = sst26_is_locked;
1199 	}
1200 #endif
1201 
1202 	/* Compute the flash size */
1203 	flash->shift = (flash->dual_flash & SF_DUAL_PARALLEL_FLASH) ? 1 : 0;
1204 	flash->page_size = info->page_size;
1205 	/*
1206 	 * The Spansion S25FS512S, S25FL032P and S25FL064P have 256b pages,
1207 	 * yet use the 0x4d00 Extended JEDEC code. The rest of the Spansion
1208 	 * flashes with the 0x4d00 Extended JEDEC code have 512b pages.
1209 	 * All of the others have 256b pages.
1210 	 */
1211 	if (JEDEC_EXT(info) == 0x4d00) {
1212 		if ((JEDEC_ID(info) != 0x0215) &&
1213 		    (JEDEC_ID(info) != 0x0216) &&
1214 		    (JEDEC_ID(info) != 0x0220))
1215 			flash->page_size = 512;
1216 	}
1217 	flash->page_size <<= flash->shift;
1218 	flash->sector_size = info->sector_size << flash->shift;
1219 	flash->size = flash->sector_size * info->n_sectors << flash->shift;
1220 #ifdef CONFIG_SF_DUAL_FLASH
1221 	if (flash->dual_flash & SF_DUAL_STACKED_FLASH)
1222 		flash->size <<= 1;
1223 #endif
1224 
1225 #ifdef CONFIG_SPI_FLASH_USE_4K_SECTORS
1226 	/* Compute erase sector and command */
1227 	if (info->flags & SECT_4K) {
1228 		flash->erase_cmd = CMD_ERASE_4K;
1229 		flash->erase_size = 4096 << flash->shift;
1230 	} else
1231 #endif
1232 	{
1233 		flash->erase_cmd = CMD_ERASE_64K;
1234 		flash->erase_size = flash->sector_size;
1235 	}
1236 
1237 	/* Now erase size becomes valid sector size */
1238 	flash->sector_size = flash->erase_size;
1239 
1240 	/* Look for read commands */
1241 	flash->read_cmd = CMD_READ_ARRAY_FAST;
1242 	if (spi->mode & SPI_RX_SLOW)
1243 		flash->read_cmd = CMD_READ_ARRAY_SLOW;
1244 	else if (spi->mode & SPI_RX_QUAD && info->flags & RD_QUAD)
1245 		flash->read_cmd = CMD_READ_QUAD_OUTPUT_FAST;
1246 	else if (spi->mode & SPI_RX_DUAL && info->flags & RD_DUAL)
1247 		flash->read_cmd = CMD_READ_DUAL_OUTPUT_FAST;
1248 
1249 	/* Look for write commands */
1250 	if (info->flags & WR_QPP && spi->mode & SPI_TX_QUAD)
1251 		flash->write_cmd = CMD_QUAD_PAGE_PROGRAM;
1252 	else
1253 		/* Go for default supported write cmd */
1254 		flash->write_cmd = CMD_PAGE_PROGRAM;
1255 
1256 	/* Set the quad enable bit - only for quad commands */
1257 	if ((flash->read_cmd == CMD_READ_QUAD_OUTPUT_FAST) ||
1258 	    (flash->read_cmd == CMD_READ_QUAD_IO_FAST) ||
1259 	    (flash->write_cmd == CMD_QUAD_PAGE_PROGRAM)) {
1260 		ret = set_quad_mode(flash, info);
1261 		if (ret) {
1262 			debug("SF: Fail to set QEB for %02x\n",
1263 			      JEDEC_MFR(info));
1264 			return -EINVAL;
1265 		}
1266 	}
1267 
1268 	/* Read dummy_byte: dummy byte is determined based on the
1269 	 * dummy cycles of a particular command.
1270 	 * Fast commands - dummy_byte = dummy_cycles/8
1271 	 * I/O commands- dummy_byte = (dummy_cycles * no.of lines)/8
1272 	 * For I/O commands except cmd[0] everything goes on no.of lines
1273 	 * based on particular command but incase of fast commands except
1274 	 * data all go on single line irrespective of command.
1275 	 */
1276 	switch (flash->read_cmd) {
1277 	case CMD_READ_QUAD_IO_FAST:
1278 		flash->dummy_byte = 2;
1279 		break;
1280 	case CMD_READ_ARRAY_SLOW:
1281 		flash->dummy_byte = 0;
1282 		break;
1283 	default:
1284 		flash->dummy_byte = 1;
1285 	}
1286 
1287 #ifdef CONFIG_SPI_FLASH_STMICRO
1288 	if (info->flags & E_FSR)
1289 		flash->flags |= SNOR_F_USE_FSR;
1290 #endif
1291 
1292 	/* Configure the BAR - discover bank cmds and read current bank */
1293 #ifdef CONFIG_SPI_FLASH_BAR
1294 	ret = read_bar(flash, info);
1295 	if (ret < 0)
1296 		return ret;
1297 #endif
1298 
1299 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
1300 	ret = spi_flash_decode_fdt(flash);
1301 	if (ret) {
1302 		debug("SF: FDT decode error\n");
1303 		return -EINVAL;
1304 	}
1305 #endif
1306 
1307 #ifndef CONFIG_SPL_BUILD
1308 	printf("SF: Detected %s with page size ", flash->name);
1309 	print_size(flash->page_size, ", erase size ");
1310 	print_size(flash->erase_size, ", total ");
1311 	print_size(flash->size, "");
1312 	if (flash->memory_map)
1313 		printf(", mapped at %p", flash->memory_map);
1314 	puts("\n");
1315 #endif
1316 
1317 #ifndef CONFIG_SPI_FLASH_BAR
1318 	if (((flash->dual_flash == SF_SINGLE_FLASH) &&
1319 	     (flash->size > SPI_FLASH_16MB_BOUN)) ||
1320 	     ((flash->dual_flash > SF_SINGLE_FLASH) &&
1321 	     (flash->size > SPI_FLASH_16MB_BOUN << 1))) {
1322 		puts("SF: Warning - Only lower 16MiB accessible,");
1323 		puts(" Full access #define CONFIG_SPI_FLASH_BAR\n");
1324 	}
1325 #endif
1326 
1327 	return 0;
1328 }
1329