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
45struct nand_onfi_vendor_macronix {
46	u8 reserved;
47	u8 reliability_func;
48} __packed;
49
50static 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
63static 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
102static 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 */
158static 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 */
198static 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
214static 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
230static 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
259static 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
281static 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
294static 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
311static 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
329static 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
354static 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
363static 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
371static 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
419out_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
433static 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
441static 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
448static 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
455static 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
484static 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
498const struct nand_manufacturer_ops macronix_nand_manuf_ops = {
499	.init = macronix_nand_init,
500};
501