1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2017 Free Electrons
4  * Copyright (C) 2017 NextThing Co
5  *
6  * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
7  */
8 
9 #include <linux/slab.h>
10 #include "linux/delay.h"
11 #include "internals.h"
12 
13 #define MACRONIX_READ_RETRY_BIT BIT(0)
14 #define MACRONIX_NUM_READ_RETRY_MODES 6
15 
16 #define ONFI_FEATURE_ADDR_MXIC_PROTECTION 0xA0
17 #define MXIC_BLOCK_PROTECTION_ALL_LOCK 0x38
18 #define MXIC_BLOCK_PROTECTION_ALL_UNLOCK 0x0
19 
20 #define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
21 #define MACRONIX_RANDOMIZER_BIT BIT(1)
22 #define MACRONIX_RANDOMIZER_ENPGM BIT(0)
23 #define MACRONIX_RANDOMIZER_RANDEN BIT(1)
24 #define MACRONIX_RANDOMIZER_RANDOPT BIT(2)
25 #define MACRONIX_RANDOMIZER_MODE_ENTER	\
26 	(MACRONIX_RANDOMIZER_ENPGM |	\
27 	 MACRONIX_RANDOMIZER_RANDEN |	\
28 	 MACRONIX_RANDOMIZER_RANDOPT)
29 #define MACRONIX_RANDOMIZER_MODE_EXIT	\
30 	(MACRONIX_RANDOMIZER_RANDEN |	\
31 	 MACRONIX_RANDOMIZER_RANDOPT)
32 
33 #define MXIC_CMD_POWER_DOWN 0xB9
34 
35 #define ONFI_FEATURE_ADDR_30LFXG18AC_OTP	0x90
36 #define MACRONIX_30LFXG18AC_OTP_START_PAGE	2
37 #define MACRONIX_30LFXG18AC_OTP_PAGES		30
38 #define MACRONIX_30LFXG18AC_OTP_PAGE_SIZE	2112
39 #define MACRONIX_30LFXG18AC_OTP_SIZE_BYTES	\
40 	(MACRONIX_30LFXG18AC_OTP_PAGES *	\
41 	 MACRONIX_30LFXG18AC_OTP_PAGE_SIZE)
42 
43 #define MACRONIX_30LFXG18AC_OTP_EN		BIT(0)
44 
45 struct nand_onfi_vendor_macronix {
46 	u8 reserved;
47 	u8 reliability_func;
48 } __packed;
49 
50 static int macronix_nand_setup_read_retry(struct nand_chip *chip, int mode)
51 {
52 	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
53 
54 	if (!chip->parameters.supports_set_get_features ||
55 	    !test_bit(ONFI_FEATURE_ADDR_READ_RETRY,
56 		      chip->parameters.set_feature_list))
57 		return -ENOTSUPP;
58 
59 	feature[0] = mode;
60 	return nand_set_features(chip, ONFI_FEATURE_ADDR_READ_RETRY, feature);
61 }
62 
63 static int macronix_nand_randomizer_check_enable(struct nand_chip *chip)
64 {
65 	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
66 	int ret;
67 
68 	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
69 				feature);
70 	if (ret < 0)
71 		return ret;
72 
73 	if (feature[0])
74 		return feature[0];
75 
76 	feature[0] = MACRONIX_RANDOMIZER_MODE_ENTER;
77 	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
78 				feature);
79 	if (ret < 0)
80 		return ret;
81 
82 	/* RANDEN and RANDOPT OTP bits are programmed */
83 	feature[0] = 0x0;
84 	ret = nand_prog_page_op(chip, 0, 0, feature, 1);
85 	if (ret < 0)
86 		return ret;
87 
88 	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
89 				feature);
90 	if (ret < 0)
91 		return ret;
92 
93 	feature[0] &= MACRONIX_RANDOMIZER_MODE_EXIT;
94 	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
95 				feature);
96 	if (ret < 0)
97 		return ret;
98 
99 	return 0;
100 }
101 
102 static void macronix_nand_onfi_init(struct nand_chip *chip)
103 {
104 	struct nand_parameters *p = &chip->parameters;
105 	struct nand_onfi_vendor_macronix *mxic;
106 	struct device_node *dn = nand_get_flash_node(chip);
107 	int rand_otp;
108 	int ret;
109 
110 	if (!p->onfi)
111 		return;
112 
113 	rand_otp = of_property_read_bool(dn, "mxic,enable-randomizer-otp");
114 
115 	mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
116 	/* Subpage write is prohibited in randomizer operatoin */
117 	if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
118 	    mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
119 		if (p->supports_set_get_features) {
120 			bitmap_set(p->set_feature_list,
121 				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
122 			bitmap_set(p->get_feature_list,
123 				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
124 			ret = macronix_nand_randomizer_check_enable(chip);
125 			if (ret < 0) {
126 				bitmap_clear(p->set_feature_list,
127 					     ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
128 					     1);
129 				bitmap_clear(p->get_feature_list,
130 					     ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
131 					     1);
132 				pr_info("Macronix NAND randomizer failed\n");
133 			} else {
134 				pr_info("Macronix NAND randomizer enabled\n");
135 			}
136 		}
137 	}
138 
139 	if ((mxic->reliability_func & MACRONIX_READ_RETRY_BIT) == 0)
140 		return;
141 
142 	chip->read_retries = MACRONIX_NUM_READ_RETRY_MODES;
143 	chip->ops.setup_read_retry = macronix_nand_setup_read_retry;
144 
145 	if (p->supports_set_get_features) {
146 		bitmap_set(p->set_feature_list,
147 			   ONFI_FEATURE_ADDR_READ_RETRY, 1);
148 		bitmap_set(p->get_feature_list,
149 			   ONFI_FEATURE_ADDR_READ_RETRY, 1);
150 	}
151 }
152 
153 /*
154  * Macronix AC series does not support using SET/GET_FEATURES to change
155  * the timings unlike what is declared in the parameter page. Unflag
156  * this feature to avoid unnecessary downturns.
157  */
158 static void macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
159 {
160 	int i;
161 	static const char * const broken_get_timings[] = {
162 		"MX30LF1G18AC",
163 		"MX30LF1G28AC",
164 		"MX30LF2G18AC",
165 		"MX30LF2G28AC",
166 		"MX30LF4G18AC",
167 		"MX30LF4G28AC",
168 		"MX60LF8G18AC",
169 		"MX30UF1G18AC",
170 		"MX30UF1G16AC",
171 		"MX30UF2G18AC",
172 		"MX30UF2G16AC",
173 		"MX30UF4G18AC",
174 		"MX30UF4G16AC",
175 		"MX30UF4G28AC",
176 	};
177 
178 	if (!chip->parameters.supports_set_get_features)
179 		return;
180 
181 	i = match_string(broken_get_timings, ARRAY_SIZE(broken_get_timings),
182 			 chip->parameters.model);
183 	if (i < 0)
184 		return;
185 
186 	bitmap_clear(chip->parameters.get_feature_list,
187 		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
188 	bitmap_clear(chip->parameters.set_feature_list,
189 		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
190 }
191 
192 /*
193  * Macronix NAND supports Block Protection by Protectoin(PT) pin;
194  * active high at power-on which protects the entire chip even the #WP is
195  * disabled. Lock/unlock protection area can be partition according to
196  * protection bits, i.e. upper 1/2 locked, upper 1/4 locked and so on.
197  */
198 static int mxic_nand_lock(struct nand_chip *chip, loff_t ofs, uint64_t len)
199 {
200 	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
201 	int ret;
202 
203 	feature[0] = MXIC_BLOCK_PROTECTION_ALL_LOCK;
204 	nand_select_target(chip, 0);
205 	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_PROTECTION,
206 				feature);
207 	nand_deselect_target(chip);
208 	if (ret)
209 		pr_err("%s all blocks failed\n", __func__);
210 
211 	return ret;
212 }
213 
214 static int mxic_nand_unlock(struct nand_chip *chip, loff_t ofs, uint64_t len)
215 {
216 	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
217 	int ret;
218 
219 	feature[0] = MXIC_BLOCK_PROTECTION_ALL_UNLOCK;
220 	nand_select_target(chip, 0);
221 	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_PROTECTION,
222 				feature);
223 	nand_deselect_target(chip);
224 	if (ret)
225 		pr_err("%s all blocks failed\n", __func__);
226 
227 	return ret;
228 }
229 
230 static void macronix_nand_block_protection_support(struct nand_chip *chip)
231 {
232 	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
233 	int ret;
234 
235 	bitmap_set(chip->parameters.get_feature_list,
236 		   ONFI_FEATURE_ADDR_MXIC_PROTECTION, 1);
237 
238 	feature[0] = MXIC_BLOCK_PROTECTION_ALL_UNLOCK;
239 	nand_select_target(chip, 0);
240 	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_PROTECTION,
241 				feature);
242 	nand_deselect_target(chip);
243 	if (ret || feature[0] != MXIC_BLOCK_PROTECTION_ALL_LOCK) {
244 		if (ret)
245 			pr_err("Block protection check failed\n");
246 
247 		bitmap_clear(chip->parameters.get_feature_list,
248 			     ONFI_FEATURE_ADDR_MXIC_PROTECTION, 1);
249 		return;
250 	}
251 
252 	bitmap_set(chip->parameters.set_feature_list,
253 		   ONFI_FEATURE_ADDR_MXIC_PROTECTION, 1);
254 
255 	chip->ops.lock_area = mxic_nand_lock;
256 	chip->ops.unlock_area = mxic_nand_unlock;
257 }
258 
259 static int nand_power_down_op(struct nand_chip *chip)
260 {
261 	int ret;
262 
263 	if (nand_has_exec_op(chip)) {
264 		struct nand_op_instr instrs[] = {
265 			NAND_OP_CMD(MXIC_CMD_POWER_DOWN, 0),
266 		};
267 
268 		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
269 
270 		ret = nand_exec_op(chip, &op);
271 		if (ret)
272 			return ret;
273 
274 	} else {
275 		chip->legacy.cmdfunc(chip, MXIC_CMD_POWER_DOWN, -1, -1);
276 	}
277 
278 	return 0;
279 }
280 
281 static int mxic_nand_suspend(struct nand_chip *chip)
282 {
283 	int ret;
284 
285 	nand_select_target(chip, 0);
286 	ret = nand_power_down_op(chip);
287 	if (ret < 0)
288 		pr_err("Suspending MXIC NAND chip failed (%d)\n", ret);
289 	nand_deselect_target(chip);
290 
291 	return ret;
292 }
293 
294 static void mxic_nand_resume(struct nand_chip *chip)
295 {
296 	/*
297 	 * Toggle #CS pin to resume NAND device and don't care
298 	 * of the others CLE, #WE, #RE pins status.
299 	 * A NAND controller ensure it is able to assert/de-assert #CS
300 	 * by sending any byte over the NAND bus.
301 	 * i.e.,
302 	 * NAND power down command or reset command w/o R/B# status checking.
303 	 */
304 	nand_select_target(chip, 0);
305 	nand_power_down_op(chip);
306 	/* The minimum of a recovery time tRDP is 35 us */
307 	usleep_range(35, 100);
308 	nand_deselect_target(chip);
309 }
310 
311 static void macronix_nand_deep_power_down_support(struct nand_chip *chip)
312 {
313 	int i;
314 	static const char * const deep_power_down_dev[] = {
315 		"MX30UF1G28AD",
316 		"MX30UF2G28AD",
317 		"MX30UF4G28AD",
318 	};
319 
320 	i = match_string(deep_power_down_dev, ARRAY_SIZE(deep_power_down_dev),
321 			 chip->parameters.model);
322 	if (i < 0)
323 		return;
324 
325 	chip->ops.suspend = mxic_nand_suspend;
326 	chip->ops.resume = mxic_nand_resume;
327 }
328 
329 static int macronix_30lfxg18ac_get_otp_info(struct mtd_info *mtd, size_t len,
330 					    size_t *retlen,
331 					    struct otp_info *buf)
332 {
333 	if (len < sizeof(*buf))
334 		return -EINVAL;
335 
336 	/* Always report that OTP is unlocked. Reason is that this
337 	 * type of flash chip doesn't provide way to check that OTP
338 	 * is locked or not: subfeature parameter is implemented as
339 	 * volatile register. Technically OTP region could be locked
340 	 * and become readonly, but as there is no way to check it,
341 	 * don't allow to lock it ('_lock_user_prot_reg' callback
342 	 * always returns -EOPNOTSUPP) and thus we report that OTP
343 	 * is unlocked.
344 	 */
345 	buf->locked = 0;
346 	buf->start = 0;
347 	buf->length = MACRONIX_30LFXG18AC_OTP_SIZE_BYTES;
348 
349 	*retlen = sizeof(*buf);
350 
351 	return 0;
352 }
353 
354 static int macronix_30lfxg18ac_otp_enable(struct nand_chip *nand)
355 {
356 	u8 feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
357 
358 	feature_buf[0] = MACRONIX_30LFXG18AC_OTP_EN;
359 	return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
360 				 feature_buf);
361 }
362 
363 static int macronix_30lfxg18ac_otp_disable(struct nand_chip *nand)
364 {
365 	u8 feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
366 
367 	return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
368 				 feature_buf);
369 }
370 
371 static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
372 					loff_t offs_in_flash,
373 					size_t len, size_t *retlen,
374 					u_char *buf, bool write)
375 {
376 	struct nand_chip *nand;
377 	size_t bytes_handled;
378 	off_t offs_in_page;
379 	u64 page;
380 	int ret;
381 
382 	nand = mtd_to_nand(mtd);
383 	nand_select_target(nand, 0);
384 
385 	ret = macronix_30lfxg18ac_otp_enable(nand);
386 	if (ret)
387 		goto out_otp;
388 
389 	page = offs_in_flash;
390 	/* 'page' will be result of division. */
391 	offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
392 	bytes_handled = 0;
393 
394 	while (bytes_handled < len &&
395 	       page < MACRONIX_30LFXG18AC_OTP_PAGES) {
396 		size_t bytes_to_handle;
397 		u64 phys_page = page + MACRONIX_30LFXG18AC_OTP_START_PAGE;
398 
399 		bytes_to_handle = min_t(size_t, len - bytes_handled,
400 					MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
401 					offs_in_page);
402 
403 		if (write)
404 			ret = nand_prog_page_op(nand, phys_page, offs_in_page,
405 						&buf[bytes_handled], bytes_to_handle);
406 		else
407 			ret = nand_read_page_op(nand, phys_page, offs_in_page,
408 						&buf[bytes_handled], bytes_to_handle);
409 		if (ret)
410 			goto out_otp;
411 
412 		bytes_handled += bytes_to_handle;
413 		offs_in_page = 0;
414 		page++;
415 	}
416 
417 	*retlen = bytes_handled;
418 
419 out_otp:
420 	if (ret)
421 		dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
422 
423 	ret = macronix_30lfxg18ac_otp_disable(nand);
424 	if (ret)
425 		dev_err(&mtd->dev, "failed to leave OTP mode after %s\n",
426 			write ? "write" : "read");
427 
428 	nand_deselect_target(nand);
429 
430 	return ret;
431 }
432 
433 static int macronix_30lfxg18ac_write_otp(struct mtd_info *mtd, loff_t to,
434 					 size_t len, size_t *rlen,
435 					 const u_char *buf)
436 {
437 	return __macronix_30lfxg18ac_rw_otp(mtd, to, len, rlen, (u_char *)buf,
438 					    true);
439 }
440 
441 static int macronix_30lfxg18ac_read_otp(struct mtd_info *mtd, loff_t from,
442 					size_t len, size_t *rlen,
443 					u_char *buf)
444 {
445 	return __macronix_30lfxg18ac_rw_otp(mtd, from, len, rlen, buf, false);
446 }
447 
448 static int macronix_30lfxg18ac_lock_otp(struct mtd_info *mtd, loff_t from,
449 					size_t len)
450 {
451 	/* See comment in 'macronix_30lfxg18ac_get_otp_info()'. */
452 	return -EOPNOTSUPP;
453 }
454 
455 static void macronix_nand_setup_otp(struct nand_chip *chip)
456 {
457 	static const char * const supported_otp_models[] = {
458 		"MX30LF1G18AC",
459 		"MX30LF2G18AC",
460 		"MX30LF4G18AC",
461 	};
462 	struct mtd_info *mtd;
463 
464 	if (match_string(supported_otp_models,
465 			 ARRAY_SIZE(supported_otp_models),
466 			 chip->parameters.model) < 0)
467 		return;
468 
469 	if (!chip->parameters.supports_set_get_features)
470 		return;
471 
472 	bitmap_set(chip->parameters.get_feature_list,
473 		   ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
474 	bitmap_set(chip->parameters.set_feature_list,
475 		   ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
476 
477 	mtd = nand_to_mtd(chip);
478 	mtd->_get_user_prot_info = macronix_30lfxg18ac_get_otp_info;
479 	mtd->_read_user_prot_reg = macronix_30lfxg18ac_read_otp;
480 	mtd->_write_user_prot_reg = macronix_30lfxg18ac_write_otp;
481 	mtd->_lock_user_prot_reg = macronix_30lfxg18ac_lock_otp;
482 }
483 
484 static int macronix_nand_init(struct nand_chip *chip)
485 {
486 	if (nand_is_slc(chip))
487 		chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE;
488 
489 	macronix_nand_fix_broken_get_timings(chip);
490 	macronix_nand_onfi_init(chip);
491 	macronix_nand_block_protection_support(chip);
492 	macronix_nand_deep_power_down_support(chip);
493 	macronix_nand_setup_otp(chip);
494 
495 	return 0;
496 }
497 
498 const struct nand_manufacturer_ops macronix_nand_manuf_ops = {
499 	.init = macronix_nand_init,
500 };
501