xref: /openbmc/u-boot/drivers/misc/mxc_ocotp.c (revision dd4671cb)
1 /*
2  * (C) Copyright 2013 ADVANSEE
3  * Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
4  *
5  * Based on Dirk Behme's
6  * https://github.com/dirkbehme/u-boot-imx6/blob/28b17e9/drivers/misc/imx_otp.c,
7  * which is based on Freescale's
8  * 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,
9  * which is:
10  * Copyright (C) 2011 Freescale Semiconductor, Inc.
11  *
12  * SPDX-License-Identifier:	GPL-2.0+
13  */
14 
15 #include <common.h>
16 #include <fuse.h>
17 #include <linux/errno.h>
18 #include <asm/io.h>
19 #include <asm/arch/clock.h>
20 #include <asm/arch/imx-regs.h>
21 #include <asm/mach-imx/sys_proto.h>
22 
23 #define BO_CTRL_WR_UNLOCK		16
24 #define BM_CTRL_WR_UNLOCK		0xffff0000
25 #define BV_CTRL_WR_UNLOCK_KEY		0x3e77
26 #define BM_CTRL_ERROR			0x00000200
27 #define BM_CTRL_BUSY			0x00000100
28 #define BO_CTRL_ADDR			0
29 #ifdef CONFIG_MX7
30 #define BM_CTRL_ADDR                    0x0000000f
31 #define BM_CTRL_RELOAD                  0x00000400
32 #elif defined(CONFIG_MX7ULP)
33 #define BM_CTRL_ADDR                    0x000000FF
34 #define BM_CTRL_RELOAD                  0x00000400
35 #define BM_OUT_STATUS_DED				0x00000400
36 #define BM_OUT_STATUS_LOCKED			0x00000800
37 #define BM_OUT_STATUS_PROGFAIL			0x00001000
38 #elif defined(CONFIG_MX8M)
39 #define BM_CTRL_ADDR			0x000000ff
40 #else
41 #define BM_CTRL_ADDR			0x0000007f
42 #endif
43 
44 #ifdef CONFIG_MX7
45 #define BO_TIMING_FSOURCE               12
46 #define BM_TIMING_FSOURCE               0x0007f000
47 #define BV_TIMING_FSOURCE_NS            1001
48 #define BO_TIMING_PROG                  0
49 #define BM_TIMING_PROG                  0x00000fff
50 #define BV_TIMING_PROG_US               10
51 #else
52 #define BO_TIMING_STROBE_READ		16
53 #define BM_TIMING_STROBE_READ		0x003f0000
54 #define BV_TIMING_STROBE_READ_NS	37
55 #define BO_TIMING_RELAX			12
56 #define BM_TIMING_RELAX			0x0000f000
57 #define BV_TIMING_RELAX_NS		17
58 #define BO_TIMING_STROBE_PROG		0
59 #define BM_TIMING_STROBE_PROG		0x00000fff
60 #define BV_TIMING_STROBE_PROG_US	10
61 #endif
62 
63 #define BM_READ_CTRL_READ_FUSE		0x00000001
64 
65 #define BF(value, field)		(((value) << BO_##field) & BM_##field)
66 
67 #define WRITE_POSTAMBLE_US		2
68 
69 #if defined(CONFIG_MX6) || defined(CONFIG_VF610)
70 #define FUSE_BANK_SIZE	0x80
71 #ifdef CONFIG_MX6SL
72 #define FUSE_BANKS	8
73 #elif defined(CONFIG_MX6ULL) || defined(CONFIG_MX6SLL)
74 #define FUSE_BANKS	9
75 #else
76 #define FUSE_BANKS	16
77 #endif
78 #elif defined CONFIG_MX7
79 #define FUSE_BANK_SIZE	0x40
80 #define FUSE_BANKS	16
81 #elif defined(CONFIG_MX7ULP)
82 #define FUSE_BANK_SIZE	0x80
83 #define FUSE_BANKS	31
84 #elif defined(CONFIG_MX8M)
85 #define FUSE_BANK_SIZE	0x40
86 #define FUSE_BANKS	64
87 #else
88 #error "Unsupported architecture\n"
89 #endif
90 
91 #if defined(CONFIG_MX6)
92 
93 /*
94  * There is a hole in shadow registers address map of size 0x100
95  * between bank 5 and bank 6 on iMX6QP, iMX6DQ, iMX6SDL, iMX6SX,
96  * iMX6UL, i.MX6ULL and i.MX6SLL.
97  * Bank 5 ends at 0x6F0 and Bank 6 starts at 0x800. When reading the fuses,
98  * we should account for this hole in address space.
99  *
100  * Similar hole exists between bank 14 and bank 15 of size
101  * 0x80 on iMX6QP, iMX6DQ, iMX6SDL and iMX6SX.
102  * Note: iMX6SL has only 0-7 banks and there is no hole.
103  * Note: iMX6UL doesn't have this one.
104  *
105  * This function is to covert user input to physical bank index.
106  * Only needed when read fuse, because we use register offset, so
107  * need to calculate real register offset.
108  * When write, no need to consider hole, always use the bank/word
109  * index from fuse map.
110  */
111 u32 fuse_bank_physical(int index)
112 {
113 	u32 phy_index;
114 
115 	if (is_mx6sl() || is_mx7ulp()) {
116 		phy_index = index;
117 	} else if (is_mx6ul() || is_mx6ull() || is_mx6sll()) {
118 		if ((is_mx6ull() || is_mx6sll()) && index == 8)
119 			index = 7;
120 
121 		if (index >= 6)
122 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
123 		else
124 			phy_index = index;
125 	} else {
126 		if (index >= 15)
127 			phy_index = fuse_bank_physical(14) + (index - 15) + 2;
128 		else if (index >= 6)
129 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
130 		else
131 			phy_index = index;
132 	}
133 	return phy_index;
134 }
135 
136 u32 fuse_word_physical(u32 bank, u32 word_index)
137 {
138 	if (is_mx6ull() || is_mx6sll()) {
139 		if (bank == 8)
140 			word_index = word_index + 4;
141 	}
142 
143 	return word_index;
144 }
145 #else
146 u32 fuse_bank_physical(int index)
147 {
148 	return index;
149 }
150 
151 u32 fuse_word_physical(u32 bank, u32 word_index)
152 {
153 	return word_index;
154 }
155 
156 #endif
157 
158 static void wait_busy(struct ocotp_regs *regs, unsigned int delay_us)
159 {
160 	while (readl(&regs->ctrl) & BM_CTRL_BUSY)
161 		udelay(delay_us);
162 }
163 
164 static void clear_error(struct ocotp_regs *regs)
165 {
166 	writel(BM_CTRL_ERROR, &regs->ctrl_clr);
167 }
168 
169 static int prepare_access(struct ocotp_regs **regs, u32 bank, u32 word,
170 				int assert, const char *caller)
171 {
172 	*regs = (struct ocotp_regs *)OCOTP_BASE_ADDR;
173 
174 	if (bank >= FUSE_BANKS ||
175 	    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 2 ||
176 	    !assert) {
177 		printf("mxc_ocotp %s(): Invalid argument\n", caller);
178 		return -EINVAL;
179 	}
180 
181 	if (is_mx6ull() || is_mx6sll()) {
182 		if ((bank == 7 || bank == 8) &&
183 		    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 3) {
184 			printf("mxc_ocotp %s(): Invalid argument\n", caller);
185 			return -EINVAL;
186 		}
187 	}
188 
189 	enable_ocotp_clk(1);
190 
191 	wait_busy(*regs, 1);
192 	clear_error(*regs);
193 
194 	return 0;
195 }
196 
197 static int finish_access(struct ocotp_regs *regs, const char *caller)
198 {
199 	u32 err;
200 
201 	err = !!(readl(&regs->ctrl) & BM_CTRL_ERROR);
202 	clear_error(regs);
203 
204 #ifdef CONFIG_MX7ULP
205 	/* Need to power down the OTP memory */
206 	writel(1, &regs->pdn);
207 #endif
208 	if (err) {
209 		printf("mxc_ocotp %s(): Access protect error\n", caller);
210 		return -EIO;
211 	}
212 
213 	return 0;
214 }
215 
216 static int prepare_read(struct ocotp_regs **regs, u32 bank, u32 word, u32 *val,
217 			const char *caller)
218 {
219 	return prepare_access(regs, bank, word, val != NULL, caller);
220 }
221 
222 int fuse_read(u32 bank, u32 word, u32 *val)
223 {
224 	struct ocotp_regs *regs;
225 	int ret;
226 	u32 phy_bank;
227 	u32 phy_word;
228 
229 	ret = prepare_read(&regs, bank, word, val, __func__);
230 	if (ret)
231 		return ret;
232 
233 	phy_bank = fuse_bank_physical(bank);
234 	phy_word = fuse_word_physical(bank, word);
235 
236 	*val = readl(&regs->bank[phy_bank].fuse_regs[phy_word << 2]);
237 
238 #ifdef CONFIG_MX7ULP
239 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
240 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
241 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
242 		return -EIO;
243 	}
244 #endif
245 	return finish_access(regs, __func__);
246 }
247 
248 #ifdef CONFIG_MX7
249 static void set_timing(struct ocotp_regs *regs)
250 {
251 	u32 ipg_clk;
252 	u32 fsource, prog;
253 	u32 timing;
254 
255 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
256 
257 	fsource = DIV_ROUND_UP((ipg_clk / 1000) * BV_TIMING_FSOURCE_NS,
258 			+       1000000) + 1;
259 	prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_PROG_US, 1000000) + 1;
260 
261 	timing = BF(fsource, TIMING_FSOURCE) | BF(prog, TIMING_PROG);
262 
263 	clrsetbits_le32(&regs->timing, BM_TIMING_FSOURCE | BM_TIMING_PROG,
264 			timing);
265 }
266 #elif defined(CONFIG_MX7ULP)
267 static void set_timing(struct ocotp_regs *regs)
268 {
269 	/* No timing set for MX7ULP */
270 }
271 
272 #else
273 static void set_timing(struct ocotp_regs *regs)
274 {
275 	u32 ipg_clk;
276 	u32 relax, strobe_read, strobe_prog;
277 	u32 timing;
278 
279 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
280 
281 	relax = DIV_ROUND_UP(ipg_clk * BV_TIMING_RELAX_NS, 1000000000) - 1;
282 	strobe_read = DIV_ROUND_UP(ipg_clk * BV_TIMING_STROBE_READ_NS,
283 					1000000000) + 2 * (relax + 1) - 1;
284 	strobe_prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_STROBE_PROG_US,
285 						1000000) + 2 * (relax + 1) - 1;
286 
287 	timing = BF(strobe_read, TIMING_STROBE_READ) |
288 			BF(relax, TIMING_RELAX) |
289 			BF(strobe_prog, TIMING_STROBE_PROG);
290 
291 	clrsetbits_le32(&regs->timing, BM_TIMING_STROBE_READ | BM_TIMING_RELAX |
292 			BM_TIMING_STROBE_PROG, timing);
293 }
294 #endif
295 
296 static void setup_direct_access(struct ocotp_regs *regs, u32 bank, u32 word,
297 				int write)
298 {
299 	u32 wr_unlock = write ? BV_CTRL_WR_UNLOCK_KEY : 0;
300 #ifdef CONFIG_MX7
301 	u32 addr = bank;
302 #elif defined CONFIG_MX8M
303 	u32 addr = bank << 2 | word;
304 #else
305 	u32 addr;
306 	/* Bank 7 and Bank 8 only supports 4 words each for i.MX6ULL */
307 	if ((is_mx6ull() || is_mx6sll()) && (bank > 7)) {
308 		bank = bank - 1;
309 		word += 4;
310 	}
311 	addr = bank << 3 | word;
312 #endif
313 
314 	set_timing(regs);
315 	clrsetbits_le32(&regs->ctrl, BM_CTRL_WR_UNLOCK | BM_CTRL_ADDR,
316 			BF(wr_unlock, CTRL_WR_UNLOCK) |
317 			BF(addr, CTRL_ADDR));
318 }
319 
320 int fuse_sense(u32 bank, u32 word, u32 *val)
321 {
322 	struct ocotp_regs *regs;
323 	int ret;
324 
325 	ret = prepare_read(&regs, bank, word, val, __func__);
326 	if (ret)
327 		return ret;
328 
329 	setup_direct_access(regs, bank, word, false);
330 	writel(BM_READ_CTRL_READ_FUSE, &regs->read_ctrl);
331 	wait_busy(regs, 1);
332 #ifdef CONFIG_MX7
333 	*val = readl((&regs->read_fuse_data0) + (word << 2));
334 #else
335 	*val = readl(&regs->read_fuse_data);
336 #endif
337 
338 #ifdef CONFIG_MX7ULP
339 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
340 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
341 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
342 		return -EIO;
343 	}
344 #endif
345 
346 	return finish_access(regs, __func__);
347 }
348 
349 static int prepare_write(struct ocotp_regs **regs, u32 bank, u32 word,
350 				const char *caller)
351 {
352 #ifdef CONFIG_MX7ULP
353 	u32 val;
354 	int ret;
355 
356 	/* Only bank 0 and 1 are redundancy mode, others are ECC mode */
357 	if (bank != 0 && bank != 1) {
358 		ret = fuse_sense(bank, word, &val);
359 		if (ret)
360 			return ret;
361 
362 		if (val != 0) {
363 			printf("mxc_ocotp: The word has been programmed, no more write\n");
364 			return -EPERM;
365 		}
366 	}
367 #endif
368 
369 	return prepare_access(regs, bank, word, true, caller);
370 }
371 
372 int fuse_prog(u32 bank, u32 word, u32 val)
373 {
374 	struct ocotp_regs *regs;
375 	int ret;
376 
377 	ret = prepare_write(&regs, bank, word, __func__);
378 	if (ret)
379 		return ret;
380 
381 	setup_direct_access(regs, bank, word, true);
382 #ifdef CONFIG_MX7
383 	switch (word) {
384 	case 0:
385 		writel(0, &regs->data1);
386 		writel(0, &regs->data2);
387 		writel(0, &regs->data3);
388 		writel(val, &regs->data0);
389 		break;
390 	case 1:
391 		writel(val, &regs->data1);
392 		writel(0, &regs->data2);
393 		writel(0, &regs->data3);
394 		writel(0, &regs->data0);
395 		break;
396 	case 2:
397 		writel(0, &regs->data1);
398 		writel(val, &regs->data2);
399 		writel(0, &regs->data3);
400 		writel(0, &regs->data0);
401 		break;
402 	case 3:
403 		writel(0, &regs->data1);
404 		writel(0, &regs->data2);
405 		writel(val, &regs->data3);
406 		writel(0, &regs->data0);
407 		break;
408 	}
409 	wait_busy(regs, BV_TIMING_PROG_US);
410 #else
411 	writel(val, &regs->data);
412 	wait_busy(regs, BV_TIMING_STROBE_PROG_US);
413 #endif
414 	udelay(WRITE_POSTAMBLE_US);
415 
416 #ifdef CONFIG_MX7ULP
417 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
418 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
419 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
420 		return -EIO;
421 	}
422 #endif
423 
424 	return finish_access(regs, __func__);
425 }
426 
427 int fuse_override(u32 bank, u32 word, u32 val)
428 {
429 	struct ocotp_regs *regs;
430 	int ret;
431 	u32 phy_bank;
432 	u32 phy_word;
433 
434 	ret = prepare_write(&regs, bank, word, __func__);
435 	if (ret)
436 		return ret;
437 
438 	phy_bank = fuse_bank_physical(bank);
439 	phy_word = fuse_word_physical(bank, word);
440 
441 	writel(val, &regs->bank[phy_bank].fuse_regs[phy_word << 2]);
442 
443 #ifdef CONFIG_MX7ULP
444 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
445 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
446 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
447 		return -EIO;
448 	}
449 #endif
450 
451 	return finish_access(regs, __func__);
452 }
453