xref: /openbmc/linux/drivers/nvmem/imx-ocotp.c (revision 6db6b729)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * i.MX6 OCOTP fusebox driver
4  *
5  * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
6  *
7  * Copyright 2019 NXP
8  *
9  * Based on the barebox ocotp driver,
10  * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
11  *	Orex Computed Radiography
12  *
13  * Write support based on the fsl_otp driver,
14  * Copyright (C) 2010-2013 Freescale Semiconductor, Inc
15  */
16 
17 #include <linux/clk.h>
18 #include <linux/device.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/nvmem-provider.h>
22 #include <linux/of.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/delay.h>
26 
27 #define IMX_OCOTP_OFFSET_B0W0		0x400 /* Offset from base address of the
28 					       * OTP Bank0 Word0
29 					       */
30 #define IMX_OCOTP_OFFSET_PER_WORD	0x10  /* Offset between the start addr
31 					       * of two consecutive OTP words.
32 					       */
33 
34 #define IMX_OCOTP_ADDR_CTRL		0x0000
35 #define IMX_OCOTP_ADDR_CTRL_SET		0x0004
36 #define IMX_OCOTP_ADDR_CTRL_CLR		0x0008
37 #define IMX_OCOTP_ADDR_TIMING		0x0010
38 #define IMX_OCOTP_ADDR_DATA0		0x0020
39 #define IMX_OCOTP_ADDR_DATA1		0x0030
40 #define IMX_OCOTP_ADDR_DATA2		0x0040
41 #define IMX_OCOTP_ADDR_DATA3		0x0050
42 
43 #define IMX_OCOTP_BM_CTRL_ADDR		0x000000FF
44 #define IMX_OCOTP_BM_CTRL_BUSY		0x00000100
45 #define IMX_OCOTP_BM_CTRL_ERROR		0x00000200
46 #define IMX_OCOTP_BM_CTRL_REL_SHADOWS	0x00000400
47 
48 #define IMX_OCOTP_BM_CTRL_ADDR_8MP		0x000001FF
49 #define IMX_OCOTP_BM_CTRL_BUSY_8MP		0x00000200
50 #define IMX_OCOTP_BM_CTRL_ERROR_8MP		0x00000400
51 #define IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP	0x00000800
52 
53 #define IMX_OCOTP_BM_CTRL_DEFAULT				\
54 	{							\
55 		.bm_addr = IMX_OCOTP_BM_CTRL_ADDR,		\
56 		.bm_busy = IMX_OCOTP_BM_CTRL_BUSY,		\
57 		.bm_error = IMX_OCOTP_BM_CTRL_ERROR,		\
58 		.bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS,\
59 	}
60 
61 #define IMX_OCOTP_BM_CTRL_8MP					\
62 	{							\
63 		.bm_addr = IMX_OCOTP_BM_CTRL_ADDR_8MP,		\
64 		.bm_busy = IMX_OCOTP_BM_CTRL_BUSY_8MP,		\
65 		.bm_error = IMX_OCOTP_BM_CTRL_ERROR_8MP,	\
66 		.bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP,\
67 	}
68 
69 #define TIMING_STROBE_PROG_US		10	/* Min time to blow a fuse */
70 #define TIMING_STROBE_READ_NS		37	/* Min time before read */
71 #define TIMING_RELAX_NS			17
72 #define DEF_FSOURCE			1001	/* > 1000 ns */
73 #define DEF_STROBE_PROG			10000	/* IPG clocks */
74 #define IMX_OCOTP_WR_UNLOCK		0x3E770000
75 #define IMX_OCOTP_READ_LOCKED_VAL	0xBADABADA
76 
77 static DEFINE_MUTEX(ocotp_mutex);
78 
79 struct ocotp_priv {
80 	struct device *dev;
81 	struct clk *clk;
82 	void __iomem *base;
83 	const struct ocotp_params *params;
84 	struct nvmem_config *config;
85 };
86 
87 struct ocotp_ctrl_reg {
88 	u32 bm_addr;
89 	u32 bm_busy;
90 	u32 bm_error;
91 	u32 bm_rel_shadows;
92 };
93 
94 struct ocotp_params {
95 	unsigned int nregs;
96 	unsigned int bank_address_words;
97 	void (*set_timing)(struct ocotp_priv *priv);
98 	struct ocotp_ctrl_reg ctrl;
99 };
100 
101 static int imx_ocotp_wait_for_busy(struct ocotp_priv *priv, u32 flags)
102 {
103 	int count;
104 	u32 c, mask;
105 	u32 bm_ctrl_busy, bm_ctrl_error;
106 	void __iomem *base = priv->base;
107 
108 	bm_ctrl_busy = priv->params->ctrl.bm_busy;
109 	bm_ctrl_error = priv->params->ctrl.bm_error;
110 
111 	mask = bm_ctrl_busy | bm_ctrl_error | flags;
112 
113 	for (count = 10000; count >= 0; count--) {
114 		c = readl(base + IMX_OCOTP_ADDR_CTRL);
115 		if (!(c & mask))
116 			break;
117 		cpu_relax();
118 	}
119 
120 	if (count < 0) {
121 		/* HW_OCOTP_CTRL[ERROR] will be set under the following
122 		 * conditions:
123 		 * - A write is performed to a shadow register during a shadow
124 		 *   reload (essentially, while HW_OCOTP_CTRL[RELOAD_SHADOWS] is
125 		 *   set. In addition, the contents of the shadow register shall
126 		 *   not be updated.
127 		 * - A write is performed to a shadow register which has been
128 		 *   locked.
129 		 * - A read is performed to from a shadow register which has
130 		 *   been read locked.
131 		 * - A program is performed to a fuse word which has been locked
132 		 * - A read is performed to from a fuse word which has been read
133 		 *   locked.
134 		 */
135 		if (c & bm_ctrl_error)
136 			return -EPERM;
137 		return -ETIMEDOUT;
138 	}
139 
140 	return 0;
141 }
142 
143 static void imx_ocotp_clr_err_if_set(struct ocotp_priv *priv)
144 {
145 	u32 c, bm_ctrl_error;
146 	void __iomem *base = priv->base;
147 
148 	bm_ctrl_error = priv->params->ctrl.bm_error;
149 
150 	c = readl(base + IMX_OCOTP_ADDR_CTRL);
151 	if (!(c & bm_ctrl_error))
152 		return;
153 
154 	writel(bm_ctrl_error, base + IMX_OCOTP_ADDR_CTRL_CLR);
155 }
156 
157 static int imx_ocotp_read(void *context, unsigned int offset,
158 			  void *val, size_t bytes)
159 {
160 	struct ocotp_priv *priv = context;
161 	unsigned int count;
162 	u8 *buf, *p;
163 	int i, ret;
164 	u32 index, num_bytes;
165 
166 	index = offset >> 2;
167 	num_bytes = round_up((offset % 4) + bytes, 4);
168 	count = num_bytes >> 2;
169 
170 	if (count > (priv->params->nregs - index))
171 		count = priv->params->nregs - index;
172 
173 	p = kzalloc(num_bytes, GFP_KERNEL);
174 	if (!p)
175 		return -ENOMEM;
176 
177 	mutex_lock(&ocotp_mutex);
178 
179 	buf = p;
180 
181 	ret = clk_prepare_enable(priv->clk);
182 	if (ret < 0) {
183 		mutex_unlock(&ocotp_mutex);
184 		dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
185 		kfree(p);
186 		return ret;
187 	}
188 
189 	ret = imx_ocotp_wait_for_busy(priv, 0);
190 	if (ret < 0) {
191 		dev_err(priv->dev, "timeout during read setup\n");
192 		goto read_end;
193 	}
194 
195 	for (i = index; i < (index + count); i++) {
196 		*(u32 *)buf = readl(priv->base + IMX_OCOTP_OFFSET_B0W0 +
197 			       i * IMX_OCOTP_OFFSET_PER_WORD);
198 
199 		/* 47.3.1.2
200 		 * For "read locked" registers 0xBADABADA will be returned and
201 		 * HW_OCOTP_CTRL[ERROR] will be set. It must be cleared by
202 		 * software before any new write, read or reload access can be
203 		 * issued
204 		 */
205 		if (*((u32 *)buf) == IMX_OCOTP_READ_LOCKED_VAL)
206 			imx_ocotp_clr_err_if_set(priv);
207 
208 		buf += 4;
209 	}
210 
211 	index = offset % 4;
212 	memcpy(val, &p[index], bytes);
213 
214 read_end:
215 	clk_disable_unprepare(priv->clk);
216 	mutex_unlock(&ocotp_mutex);
217 
218 	kfree(p);
219 
220 	return ret;
221 }
222 
223 static int imx_ocotp_cell_pp(void *context, const char *id, int index,
224 			     unsigned int offset, void *data, size_t bytes)
225 {
226 	u8 *buf = data;
227 	int i;
228 
229 	/* Deal with some post processing of nvmem cell data */
230 	if (id && !strcmp(id, "mac-address"))
231 		for (i = 0; i < bytes / 2; i++)
232 			swap(buf[i], buf[bytes - i - 1]);
233 
234 	return 0;
235 }
236 
237 static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
238 {
239 	unsigned long clk_rate;
240 	unsigned long strobe_read, relax, strobe_prog;
241 	u32 timing;
242 
243 	/* 47.3.1.3.1
244 	 * Program HW_OCOTP_TIMING[STROBE_PROG] and HW_OCOTP_TIMING[RELAX]
245 	 * fields with timing values to match the current frequency of the
246 	 * ipg_clk. OTP writes will work at maximum bus frequencies as long
247 	 * as the HW_OCOTP_TIMING parameters are set correctly.
248 	 *
249 	 * Note: there are minimum timings required to ensure an OTP fuse burns
250 	 * correctly that are independent of the ipg_clk. Those values are not
251 	 * formally documented anywhere however, working from the minimum
252 	 * timings given in u-boot we can say:
253 	 *
254 	 * - Minimum STROBE_PROG time is 10 microseconds. Intuitively 10
255 	 *   microseconds feels about right as representative of a minimum time
256 	 *   to physically burn out a fuse.
257 	 *
258 	 * - Minimum STROBE_READ i.e. the time to wait post OTP fuse burn before
259 	 *   performing another read is 37 nanoseconds
260 	 *
261 	 * - Minimum RELAX timing is 17 nanoseconds. This final RELAX minimum
262 	 *   timing is not entirely clear the documentation says "This
263 	 *   count value specifies the time to add to all default timing
264 	 *   parameters other than the Tpgm and Trd. It is given in number
265 	 *   of ipg_clk periods." where Tpgm and Trd refer to STROBE_PROG
266 	 *   and STROBE_READ respectively. What the other timing parameters
267 	 *   are though, is not specified. Experience shows a zero RELAX
268 	 *   value will mess up a re-load of the shadow registers post OTP
269 	 *   burn.
270 	 */
271 	clk_rate = clk_get_rate(priv->clk);
272 
273 	relax = DIV_ROUND_UP(clk_rate * TIMING_RELAX_NS, 1000000000) - 1;
274 	strobe_read = DIV_ROUND_UP(clk_rate * TIMING_STROBE_READ_NS,
275 				   1000000000);
276 	strobe_read += 2 * (relax + 1) - 1;
277 	strobe_prog = DIV_ROUND_CLOSEST(clk_rate * TIMING_STROBE_PROG_US,
278 					1000000);
279 	strobe_prog += 2 * (relax + 1) - 1;
280 
281 	timing = readl(priv->base + IMX_OCOTP_ADDR_TIMING) & 0x0FC00000;
282 	timing |= strobe_prog & 0x00000FFF;
283 	timing |= (relax       << 12) & 0x0000F000;
284 	timing |= (strobe_read << 16) & 0x003F0000;
285 
286 	writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
287 }
288 
289 static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
290 {
291 	unsigned long clk_rate;
292 	u64 fsource, strobe_prog;
293 	u32 timing;
294 
295 	/* i.MX 7Solo Applications Processor Reference Manual, Rev. 0.1
296 	 * 6.4.3.3
297 	 */
298 	clk_rate = clk_get_rate(priv->clk);
299 	fsource = DIV_ROUND_UP_ULL((u64)clk_rate * DEF_FSOURCE,
300 				   NSEC_PER_SEC) + 1;
301 	strobe_prog = DIV_ROUND_CLOSEST_ULL((u64)clk_rate * DEF_STROBE_PROG,
302 					    NSEC_PER_SEC) + 1;
303 
304 	timing = strobe_prog & 0x00000FFF;
305 	timing |= (fsource << 12) & 0x000FF000;
306 
307 	writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
308 }
309 
310 static int imx_ocotp_write(void *context, unsigned int offset, void *val,
311 			   size_t bytes)
312 {
313 	struct ocotp_priv *priv = context;
314 	u32 *buf = val;
315 	int ret;
316 
317 	u32 ctrl;
318 	u8 waddr;
319 	u8 word = 0;
320 
321 	/* allow only writing one complete OTP word at a time */
322 	if ((bytes != priv->config->word_size) ||
323 	    (offset % priv->config->word_size))
324 		return -EINVAL;
325 
326 	mutex_lock(&ocotp_mutex);
327 
328 	ret = clk_prepare_enable(priv->clk);
329 	if (ret < 0) {
330 		mutex_unlock(&ocotp_mutex);
331 		dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
332 		return ret;
333 	}
334 
335 	/* Setup the write timing values */
336 	priv->params->set_timing(priv);
337 
338 	/* 47.3.1.3.2
339 	 * Check that HW_OCOTP_CTRL[BUSY] and HW_OCOTP_CTRL[ERROR] are clear.
340 	 * Overlapped accesses are not supported by the controller. Any pending
341 	 * write or reload must be completed before a write access can be
342 	 * requested.
343 	 */
344 	ret = imx_ocotp_wait_for_busy(priv, 0);
345 	if (ret < 0) {
346 		dev_err(priv->dev, "timeout during timing setup\n");
347 		goto write_end;
348 	}
349 
350 	/* 47.3.1.3.3
351 	 * Write the requested address to HW_OCOTP_CTRL[ADDR] and program the
352 	 * unlock code into HW_OCOTP_CTRL[WR_UNLOCK]. This must be programmed
353 	 * for each write access. The lock code is documented in the register
354 	 * description. Both the unlock code and address can be written in the
355 	 * same operation.
356 	 */
357 	if (priv->params->bank_address_words != 0) {
358 		/*
359 		 * In banked/i.MX7 mode the OTP register bank goes into waddr
360 		 * see i.MX 7Solo Applications Processor Reference Manual, Rev.
361 		 * 0.1 section 6.4.3.1
362 		 */
363 		offset = offset / priv->config->word_size;
364 		waddr = offset / priv->params->bank_address_words;
365 		word  = offset & (priv->params->bank_address_words - 1);
366 	} else {
367 		/*
368 		 * Non-banked i.MX6 mode.
369 		 * OTP write/read address specifies one of 128 word address
370 		 * locations
371 		 */
372 		waddr = offset / 4;
373 	}
374 
375 	ctrl = readl(priv->base + IMX_OCOTP_ADDR_CTRL);
376 	ctrl &= ~priv->params->ctrl.bm_addr;
377 	ctrl |= waddr & priv->params->ctrl.bm_addr;
378 	ctrl |= IMX_OCOTP_WR_UNLOCK;
379 
380 	writel(ctrl, priv->base + IMX_OCOTP_ADDR_CTRL);
381 
382 	/* 47.3.1.3.4
383 	 * Write the data to the HW_OCOTP_DATA register. This will automatically
384 	 * set HW_OCOTP_CTRL[BUSY] and clear HW_OCOTP_CTRL[WR_UNLOCK]. To
385 	 * protect programming same OTP bit twice, before program OCOTP will
386 	 * automatically read fuse value in OTP and use read value to mask
387 	 * program data. The controller will use masked program data to program
388 	 * a 32-bit word in the OTP per the address in HW_OCOTP_CTRL[ADDR]. Bit
389 	 * fields with 1's will result in that OTP bit being programmed. Bit
390 	 * fields with 0's will be ignored. At the same time that the write is
391 	 * accepted, the controller makes an internal copy of
392 	 * HW_OCOTP_CTRL[ADDR] which cannot be updated until the next write
393 	 * sequence is initiated. This copy guarantees that erroneous writes to
394 	 * HW_OCOTP_CTRL[ADDR] will not affect an active write operation. It
395 	 * should also be noted that during the programming HW_OCOTP_DATA will
396 	 * shift right (with zero fill). This shifting is required to program
397 	 * the OTP serially. During the write operation, HW_OCOTP_DATA cannot be
398 	 * modified.
399 	 * Note: on i.MX7 there are four data fields to write for banked write
400 	 *       with the fuse blowing operation only taking place after data0
401 	 *	 has been written. This is why data0 must always be the last
402 	 *	 register written.
403 	 */
404 	if (priv->params->bank_address_words != 0) {
405 		/* Banked/i.MX7 mode */
406 		switch (word) {
407 		case 0:
408 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
409 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
410 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
411 			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
412 			break;
413 		case 1:
414 			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA1);
415 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
416 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
417 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
418 			break;
419 		case 2:
420 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
421 			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA2);
422 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
423 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
424 			break;
425 		case 3:
426 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
427 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
428 			writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA3);
429 			writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
430 			break;
431 		}
432 	} else {
433 		/* Non-banked i.MX6 mode */
434 		writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
435 	}
436 
437 	/* 47.4.1.4.5
438 	 * Once complete, the controller will clear BUSY. A write request to a
439 	 * protected or locked region will result in no OTP access and no
440 	 * setting of HW_OCOTP_CTRL[BUSY]. In addition HW_OCOTP_CTRL[ERROR] will
441 	 * be set. It must be cleared by software before any new write access
442 	 * can be issued.
443 	 */
444 	ret = imx_ocotp_wait_for_busy(priv, 0);
445 	if (ret < 0) {
446 		if (ret == -EPERM) {
447 			dev_err(priv->dev, "failed write to locked region");
448 			imx_ocotp_clr_err_if_set(priv);
449 		} else {
450 			dev_err(priv->dev, "timeout during data write\n");
451 		}
452 		goto write_end;
453 	}
454 
455 	/* 47.3.1.4
456 	 * Write Postamble: Due to internal electrical characteristics of the
457 	 * OTP during writes, all OTP operations following a write must be
458 	 * separated by 2 us after the clearing of HW_OCOTP_CTRL_BUSY following
459 	 * the write.
460 	 */
461 	udelay(2);
462 
463 	/* reload all shadow registers */
464 	writel(priv->params->ctrl.bm_rel_shadows,
465 	       priv->base + IMX_OCOTP_ADDR_CTRL_SET);
466 	ret = imx_ocotp_wait_for_busy(priv,
467 				      priv->params->ctrl.bm_rel_shadows);
468 	if (ret < 0)
469 		dev_err(priv->dev, "timeout during shadow register reload\n");
470 
471 write_end:
472 	clk_disable_unprepare(priv->clk);
473 	mutex_unlock(&ocotp_mutex);
474 	return ret < 0 ? ret : bytes;
475 }
476 
477 static struct nvmem_config imx_ocotp_nvmem_config = {
478 	.name = "imx-ocotp",
479 	.read_only = false,
480 	.word_size = 4,
481 	.stride = 1,
482 	.reg_read = imx_ocotp_read,
483 	.reg_write = imx_ocotp_write,
484 };
485 
486 static const struct ocotp_params imx6q_params = {
487 	.nregs = 128,
488 	.bank_address_words = 0,
489 	.set_timing = imx_ocotp_set_imx6_timing,
490 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
491 };
492 
493 static const struct ocotp_params imx6sl_params = {
494 	.nregs = 64,
495 	.bank_address_words = 0,
496 	.set_timing = imx_ocotp_set_imx6_timing,
497 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
498 };
499 
500 static const struct ocotp_params imx6sll_params = {
501 	.nregs = 80,
502 	.bank_address_words = 0,
503 	.set_timing = imx_ocotp_set_imx6_timing,
504 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
505 };
506 
507 static const struct ocotp_params imx6sx_params = {
508 	.nregs = 128,
509 	.bank_address_words = 0,
510 	.set_timing = imx_ocotp_set_imx6_timing,
511 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
512 };
513 
514 static const struct ocotp_params imx6ul_params = {
515 	.nregs = 144,
516 	.bank_address_words = 0,
517 	.set_timing = imx_ocotp_set_imx6_timing,
518 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
519 };
520 
521 static const struct ocotp_params imx6ull_params = {
522 	.nregs = 80,
523 	.bank_address_words = 0,
524 	.set_timing = imx_ocotp_set_imx6_timing,
525 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
526 };
527 
528 static const struct ocotp_params imx7d_params = {
529 	.nregs = 64,
530 	.bank_address_words = 4,
531 	.set_timing = imx_ocotp_set_imx7_timing,
532 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
533 };
534 
535 static const struct ocotp_params imx7ulp_params = {
536 	.nregs = 256,
537 	.bank_address_words = 0,
538 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
539 };
540 
541 static const struct ocotp_params imx8mq_params = {
542 	.nregs = 256,
543 	.bank_address_words = 0,
544 	.set_timing = imx_ocotp_set_imx6_timing,
545 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
546 };
547 
548 static const struct ocotp_params imx8mm_params = {
549 	.nregs = 256,
550 	.bank_address_words = 0,
551 	.set_timing = imx_ocotp_set_imx6_timing,
552 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
553 };
554 
555 static const struct ocotp_params imx8mn_params = {
556 	.nregs = 256,
557 	.bank_address_words = 0,
558 	.set_timing = imx_ocotp_set_imx6_timing,
559 	.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
560 };
561 
562 static const struct ocotp_params imx8mp_params = {
563 	.nregs = 384,
564 	.bank_address_words = 0,
565 	.set_timing = imx_ocotp_set_imx6_timing,
566 	.ctrl = IMX_OCOTP_BM_CTRL_8MP,
567 };
568 
569 static const struct of_device_id imx_ocotp_dt_ids[] = {
570 	{ .compatible = "fsl,imx6q-ocotp",  .data = &imx6q_params },
571 	{ .compatible = "fsl,imx6sl-ocotp", .data = &imx6sl_params },
572 	{ .compatible = "fsl,imx6sx-ocotp", .data = &imx6sx_params },
573 	{ .compatible = "fsl,imx6ul-ocotp", .data = &imx6ul_params },
574 	{ .compatible = "fsl,imx6ull-ocotp", .data = &imx6ull_params },
575 	{ .compatible = "fsl,imx7d-ocotp",  .data = &imx7d_params },
576 	{ .compatible = "fsl,imx6sll-ocotp", .data = &imx6sll_params },
577 	{ .compatible = "fsl,imx7ulp-ocotp", .data = &imx7ulp_params },
578 	{ .compatible = "fsl,imx8mq-ocotp", .data = &imx8mq_params },
579 	{ .compatible = "fsl,imx8mm-ocotp", .data = &imx8mm_params },
580 	{ .compatible = "fsl,imx8mn-ocotp", .data = &imx8mn_params },
581 	{ .compatible = "fsl,imx8mp-ocotp", .data = &imx8mp_params },
582 	{ },
583 };
584 MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids);
585 
586 static void imx_ocotp_fixup_cell_info(struct nvmem_device *nvmem,
587 				      struct nvmem_layout *layout,
588 				      struct nvmem_cell_info *cell)
589 {
590 	cell->read_post_process = imx_ocotp_cell_pp;
591 }
592 
593 static struct nvmem_layout imx_ocotp_layout = {
594 	.fixup_cell_info = imx_ocotp_fixup_cell_info,
595 };
596 
597 static int imx_ocotp_probe(struct platform_device *pdev)
598 {
599 	struct device *dev = &pdev->dev;
600 	struct ocotp_priv *priv;
601 	struct nvmem_device *nvmem;
602 
603 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
604 	if (!priv)
605 		return -ENOMEM;
606 
607 	priv->dev = dev;
608 
609 	priv->base = devm_platform_ioremap_resource(pdev, 0);
610 	if (IS_ERR(priv->base))
611 		return PTR_ERR(priv->base);
612 
613 	priv->clk = devm_clk_get(dev, NULL);
614 	if (IS_ERR(priv->clk))
615 		return PTR_ERR(priv->clk);
616 
617 	priv->params = of_device_get_match_data(&pdev->dev);
618 	imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
619 	imx_ocotp_nvmem_config.dev = dev;
620 	imx_ocotp_nvmem_config.priv = priv;
621 	imx_ocotp_nvmem_config.layout = &imx_ocotp_layout;
622 
623 	priv->config = &imx_ocotp_nvmem_config;
624 
625 	clk_prepare_enable(priv->clk);
626 	imx_ocotp_clr_err_if_set(priv);
627 	clk_disable_unprepare(priv->clk);
628 
629 	nvmem = devm_nvmem_register(dev, &imx_ocotp_nvmem_config);
630 
631 	return PTR_ERR_OR_ZERO(nvmem);
632 }
633 
634 static struct platform_driver imx_ocotp_driver = {
635 	.probe	= imx_ocotp_probe,
636 	.driver = {
637 		.name	= "imx_ocotp",
638 		.of_match_table = imx_ocotp_dt_ids,
639 	},
640 };
641 module_platform_driver(imx_ocotp_driver);
642 
643 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
644 MODULE_DESCRIPTION("i.MX6/i.MX7 OCOTP fuse box driver");
645 MODULE_LICENSE("GPL v2");
646