xref: /openbmc/u-boot/drivers/misc/mxc_ocotp.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2013 ADVANSEE
4  * Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
5  *
6  * Based on Dirk Behme's
7  * https://github.com/dirkbehme/u-boot-imx6/blob/28b17e9/drivers/misc/imx_otp.c,
8  * which is based on Freescale's
9  * http://git.freescale.com/git/cgit.cgi/imx/uboot-imx.git/tree/drivers/misc/imx_otp.c?h=imx_v2009.08_1.1.0&id=9aa74e6,
10  * which is:
11  * Copyright (C) 2011 Freescale Semiconductor, Inc.
12  */
13 
14 #include <common.h>
15 #include <fuse.h>
16 #include <linux/errno.h>
17 #include <asm/io.h>
18 #include <asm/arch/clock.h>
19 #include <asm/arch/imx-regs.h>
20 #include <asm/mach-imx/sys_proto.h>
21 
22 #define BO_CTRL_WR_UNLOCK		16
23 #define BM_CTRL_WR_UNLOCK		0xffff0000
24 #define BV_CTRL_WR_UNLOCK_KEY		0x3e77
25 #define BM_CTRL_ERROR			0x00000200
26 #define BM_CTRL_BUSY			0x00000100
27 #define BO_CTRL_ADDR			0
28 #ifdef CONFIG_MX7
29 #define BM_CTRL_ADDR                    0x0000000f
30 #define BM_CTRL_RELOAD                  0x00000400
31 #elif defined(CONFIG_MX7ULP)
32 #define BM_CTRL_ADDR                    0x000000FF
33 #define BM_CTRL_RELOAD                  0x00000400
34 #define BM_OUT_STATUS_DED				0x00000400
35 #define BM_OUT_STATUS_LOCKED			0x00000800
36 #define BM_OUT_STATUS_PROGFAIL			0x00001000
37 #elif defined(CONFIG_MX8M)
38 #define BM_CTRL_ADDR			0x000000ff
39 #else
40 #define BM_CTRL_ADDR			0x0000007f
41 #endif
42 
43 #ifdef CONFIG_MX7
44 #define BO_TIMING_FSOURCE               12
45 #define BM_TIMING_FSOURCE               0x0007f000
46 #define BV_TIMING_FSOURCE_NS            1001
47 #define BO_TIMING_PROG                  0
48 #define BM_TIMING_PROG                  0x00000fff
49 #define BV_TIMING_PROG_US               10
50 #else
51 #define BO_TIMING_STROBE_READ		16
52 #define BM_TIMING_STROBE_READ		0x003f0000
53 #define BV_TIMING_STROBE_READ_NS	37
54 #define BO_TIMING_RELAX			12
55 #define BM_TIMING_RELAX			0x0000f000
56 #define BV_TIMING_RELAX_NS		17
57 #define BO_TIMING_STROBE_PROG		0
58 #define BM_TIMING_STROBE_PROG		0x00000fff
59 #define BV_TIMING_STROBE_PROG_US	10
60 #endif
61 
62 #define BM_READ_CTRL_READ_FUSE		0x00000001
63 
64 #define BF(value, field)		(((value) << BO_##field) & BM_##field)
65 
66 #define WRITE_POSTAMBLE_US		2
67 
68 #if defined(CONFIG_MX6) || defined(CONFIG_VF610)
69 #define FUSE_BANK_SIZE	0x80
70 #ifdef CONFIG_MX6SL
71 #define FUSE_BANKS	8
72 #elif defined(CONFIG_MX6ULL) || defined(CONFIG_MX6SLL)
73 #define FUSE_BANKS	9
74 #else
75 #define FUSE_BANKS	16
76 #endif
77 #elif defined CONFIG_MX7
78 #define FUSE_BANK_SIZE	0x40
79 #define FUSE_BANKS	16
80 #elif defined(CONFIG_MX7ULP)
81 #define FUSE_BANK_SIZE	0x80
82 #define FUSE_BANKS	31
83 #elif defined(CONFIG_MX8M)
84 #define FUSE_BANK_SIZE	0x40
85 #define FUSE_BANKS	64
86 #else
87 #error "Unsupported architecture\n"
88 #endif
89 
90 #if defined(CONFIG_MX6)
91 
92 /*
93  * There is a hole in shadow registers address map of size 0x100
94  * between bank 5 and bank 6 on iMX6QP, iMX6DQ, iMX6SDL, iMX6SX,
95  * iMX6UL, i.MX6ULL and i.MX6SLL.
96  * Bank 5 ends at 0x6F0 and Bank 6 starts at 0x800. When reading the fuses,
97  * we should account for this hole in address space.
98  *
99  * Similar hole exists between bank 14 and bank 15 of size
100  * 0x80 on iMX6QP, iMX6DQ, iMX6SDL and iMX6SX.
101  * Note: iMX6SL has only 0-7 banks and there is no hole.
102  * Note: iMX6UL doesn't have this one.
103  *
104  * This function is to covert user input to physical bank index.
105  * Only needed when read fuse, because we use register offset, so
106  * need to calculate real register offset.
107  * When write, no need to consider hole, always use the bank/word
108  * index from fuse map.
109  */
110 u32 fuse_bank_physical(int index)
111 {
112 	u32 phy_index;
113 
114 	if (is_mx6sl() || is_mx7ulp()) {
115 		phy_index = index;
116 	} else if (is_mx6ul() || is_mx6ull() || is_mx6sll()) {
117 		if ((is_mx6ull() || is_mx6sll()) && index == 8)
118 			index = 7;
119 
120 		if (index >= 6)
121 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
122 		else
123 			phy_index = index;
124 	} else {
125 		if (index >= 15)
126 			phy_index = fuse_bank_physical(14) + (index - 15) + 2;
127 		else if (index >= 6)
128 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
129 		else
130 			phy_index = index;
131 	}
132 	return phy_index;
133 }
134 
135 u32 fuse_word_physical(u32 bank, u32 word_index)
136 {
137 	if (is_mx6ull() || is_mx6sll()) {
138 		if (bank == 8)
139 			word_index = word_index + 4;
140 	}
141 
142 	return word_index;
143 }
144 #else
145 u32 fuse_bank_physical(int index)
146 {
147 	return index;
148 }
149 
150 u32 fuse_word_physical(u32 bank, u32 word_index)
151 {
152 	return word_index;
153 }
154 
155 #endif
156 
157 static void wait_busy(struct ocotp_regs *regs, unsigned int delay_us)
158 {
159 	while (readl(&regs->ctrl) & BM_CTRL_BUSY)
160 		udelay(delay_us);
161 }
162 
163 static void clear_error(struct ocotp_regs *regs)
164 {
165 	writel(BM_CTRL_ERROR, &regs->ctrl_clr);
166 }
167 
168 static int prepare_access(struct ocotp_regs **regs, u32 bank, u32 word,
169 				int assert, const char *caller)
170 {
171 	*regs = (struct ocotp_regs *)OCOTP_BASE_ADDR;
172 
173 	if (bank >= FUSE_BANKS ||
174 	    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 2 ||
175 	    !assert) {
176 		printf("mxc_ocotp %s(): Invalid argument\n", caller);
177 		return -EINVAL;
178 	}
179 
180 	if (is_mx6ull() || is_mx6sll()) {
181 		if ((bank == 7 || bank == 8) &&
182 		    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 3) {
183 			printf("mxc_ocotp %s(): Invalid argument\n", caller);
184 			return -EINVAL;
185 		}
186 	}
187 
188 	enable_ocotp_clk(1);
189 
190 	wait_busy(*regs, 1);
191 	clear_error(*regs);
192 
193 	return 0;
194 }
195 
196 static int finish_access(struct ocotp_regs *regs, const char *caller)
197 {
198 	u32 err;
199 
200 	err = !!(readl(&regs->ctrl) & BM_CTRL_ERROR);
201 	clear_error(regs);
202 
203 #ifdef CONFIG_MX7ULP
204 	/* Need to power down the OTP memory */
205 	writel(1, &regs->pdn);
206 #endif
207 	if (err) {
208 		printf("mxc_ocotp %s(): Access protect error\n", caller);
209 		return -EIO;
210 	}
211 
212 	return 0;
213 }
214 
215 static int prepare_read(struct ocotp_regs **regs, u32 bank, u32 word, u32 *val,
216 			const char *caller)
217 {
218 	return prepare_access(regs, bank, word, val != NULL, caller);
219 }
220 
221 int fuse_read(u32 bank, u32 word, u32 *val)
222 {
223 	struct ocotp_regs *regs;
224 	int ret;
225 	u32 phy_bank;
226 	u32 phy_word;
227 
228 	ret = prepare_read(&regs, bank, word, val, __func__);
229 	if (ret)
230 		return ret;
231 
232 	phy_bank = fuse_bank_physical(bank);
233 	phy_word = fuse_word_physical(bank, word);
234 
235 	*val = readl(&regs->bank[phy_bank].fuse_regs[phy_word << 2]);
236 
237 #ifdef CONFIG_MX7ULP
238 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
239 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
240 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
241 		return -EIO;
242 	}
243 #endif
244 	return finish_access(regs, __func__);
245 }
246 
247 #ifdef CONFIG_MX7
248 static void set_timing(struct ocotp_regs *regs)
249 {
250 	u32 ipg_clk;
251 	u32 fsource, prog;
252 	u32 timing;
253 
254 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
255 
256 	fsource = DIV_ROUND_UP((ipg_clk / 1000) * BV_TIMING_FSOURCE_NS,
257 			+       1000000) + 1;
258 	prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_PROG_US, 1000000) + 1;
259 
260 	timing = BF(fsource, TIMING_FSOURCE) | BF(prog, TIMING_PROG);
261 
262 	clrsetbits_le32(&regs->timing, BM_TIMING_FSOURCE | BM_TIMING_PROG,
263 			timing);
264 }
265 #elif defined(CONFIG_MX7ULP)
266 static void set_timing(struct ocotp_regs *regs)
267 {
268 	/* No timing set for MX7ULP */
269 }
270 
271 #else
272 static void set_timing(struct ocotp_regs *regs)
273 {
274 	u32 ipg_clk;
275 	u32 relax, strobe_read, strobe_prog;
276 	u32 timing;
277 
278 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
279 
280 	relax = DIV_ROUND_UP(ipg_clk * BV_TIMING_RELAX_NS, 1000000000) - 1;
281 	strobe_read = DIV_ROUND_UP(ipg_clk * BV_TIMING_STROBE_READ_NS,
282 					1000000000) + 2 * (relax + 1) - 1;
283 	strobe_prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_STROBE_PROG_US,
284 						1000000) + 2 * (relax + 1) - 1;
285 
286 	timing = BF(strobe_read, TIMING_STROBE_READ) |
287 			BF(relax, TIMING_RELAX) |
288 			BF(strobe_prog, TIMING_STROBE_PROG);
289 
290 	clrsetbits_le32(&regs->timing, BM_TIMING_STROBE_READ | BM_TIMING_RELAX |
291 			BM_TIMING_STROBE_PROG, timing);
292 }
293 #endif
294 
295 static void setup_direct_access(struct ocotp_regs *regs, u32 bank, u32 word,
296 				int write)
297 {
298 	u32 wr_unlock = write ? BV_CTRL_WR_UNLOCK_KEY : 0;
299 #ifdef CONFIG_MX7
300 	u32 addr = bank;
301 #elif defined CONFIG_MX8M
302 	u32 addr = bank << 2 | word;
303 #else
304 	u32 addr;
305 	/* Bank 7 and Bank 8 only supports 4 words each for i.MX6ULL */
306 	if ((is_mx6ull() || is_mx6sll()) && (bank > 7)) {
307 		bank = bank - 1;
308 		word += 4;
309 	}
310 	addr = bank << 3 | word;
311 #endif
312 
313 	set_timing(regs);
314 	clrsetbits_le32(&regs->ctrl, BM_CTRL_WR_UNLOCK | BM_CTRL_ADDR,
315 			BF(wr_unlock, CTRL_WR_UNLOCK) |
316 			BF(addr, CTRL_ADDR));
317 }
318 
319 int fuse_sense(u32 bank, u32 word, u32 *val)
320 {
321 	struct ocotp_regs *regs;
322 	int ret;
323 
324 	ret = prepare_read(&regs, bank, word, val, __func__);
325 	if (ret)
326 		return ret;
327 
328 	setup_direct_access(regs, bank, word, false);
329 	writel(BM_READ_CTRL_READ_FUSE, &regs->read_ctrl);
330 	wait_busy(regs, 1);
331 #ifdef CONFIG_MX7
332 	*val = readl((&regs->read_fuse_data0) + (word << 2));
333 #else
334 	*val = readl(&regs->read_fuse_data);
335 #endif
336 
337 #ifdef CONFIG_MX7ULP
338 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
339 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
340 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
341 		return -EIO;
342 	}
343 #endif
344 
345 	return finish_access(regs, __func__);
346 }
347 
348 static int prepare_write(struct ocotp_regs **regs, u32 bank, u32 word,
349 				const char *caller)
350 {
351 #ifdef CONFIG_MX7ULP
352 	u32 val;
353 	int ret;
354 
355 	/* Only bank 0 and 1 are redundancy mode, others are ECC mode */
356 	if (bank != 0 && bank != 1) {
357 		ret = fuse_sense(bank, word, &val);
358 		if (ret)
359 			return ret;
360 
361 		if (val != 0) {
362 			printf("mxc_ocotp: The word has been programmed, no more write\n");
363 			return -EPERM;
364 		}
365 	}
366 #endif
367 
368 	return prepare_access(regs, bank, word, true, caller);
369 }
370 
371 int fuse_prog(u32 bank, u32 word, u32 val)
372 {
373 	struct ocotp_regs *regs;
374 	int ret;
375 
376 	ret = prepare_write(&regs, bank, word, __func__);
377 	if (ret)
378 		return ret;
379 
380 	setup_direct_access(regs, bank, word, true);
381 #ifdef CONFIG_MX7
382 	switch (word) {
383 	case 0:
384 		writel(0, &regs->data1);
385 		writel(0, &regs->data2);
386 		writel(0, &regs->data3);
387 		writel(val, &regs->data0);
388 		break;
389 	case 1:
390 		writel(val, &regs->data1);
391 		writel(0, &regs->data2);
392 		writel(0, &regs->data3);
393 		writel(0, &regs->data0);
394 		break;
395 	case 2:
396 		writel(0, &regs->data1);
397 		writel(val, &regs->data2);
398 		writel(0, &regs->data3);
399 		writel(0, &regs->data0);
400 		break;
401 	case 3:
402 		writel(0, &regs->data1);
403 		writel(0, &regs->data2);
404 		writel(val, &regs->data3);
405 		writel(0, &regs->data0);
406 		break;
407 	}
408 	wait_busy(regs, BV_TIMING_PROG_US);
409 #else
410 	writel(val, &regs->data);
411 	wait_busy(regs, BV_TIMING_STROBE_PROG_US);
412 #endif
413 	udelay(WRITE_POSTAMBLE_US);
414 
415 #ifdef CONFIG_MX7ULP
416 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
417 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
418 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
419 		return -EIO;
420 	}
421 #endif
422 
423 	return finish_access(regs, __func__);
424 }
425 
426 int fuse_override(u32 bank, u32 word, u32 val)
427 {
428 	struct ocotp_regs *regs;
429 	int ret;
430 	u32 phy_bank;
431 	u32 phy_word;
432 
433 	ret = prepare_write(&regs, bank, word, __func__);
434 	if (ret)
435 		return ret;
436 
437 	phy_bank = fuse_bank_physical(bank);
438 	phy_word = fuse_word_physical(bank, word);
439 
440 	writel(val, &regs->bank[phy_bank].fuse_regs[phy_word << 2]);
441 
442 #ifdef CONFIG_MX7ULP
443 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
444 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
445 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
446 		return -EIO;
447 	}
448 #endif
449 
450 	return finish_access(regs, __func__);
451 }
452