xref: /openbmc/u-boot/drivers/misc/mxc_ocotp.c (revision d891ab95)
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/imx-common/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 #else
39 #define BM_CTRL_ADDR			0x0000007f
40 #endif
41 
42 #ifdef CONFIG_MX7
43 #define BO_TIMING_FSOURCE               12
44 #define BM_TIMING_FSOURCE               0x0007f000
45 #define BV_TIMING_FSOURCE_NS            1001
46 #define BO_TIMING_PROG                  0
47 #define BM_TIMING_PROG                  0x00000fff
48 #define BV_TIMING_PROG_US               10
49 #else
50 #define BO_TIMING_STROBE_READ		16
51 #define BM_TIMING_STROBE_READ		0x003f0000
52 #define BV_TIMING_STROBE_READ_NS	37
53 #define BO_TIMING_RELAX			12
54 #define BM_TIMING_RELAX			0x0000f000
55 #define BV_TIMING_RELAX_NS		17
56 #define BO_TIMING_STROBE_PROG		0
57 #define BM_TIMING_STROBE_PROG		0x00000fff
58 #define BV_TIMING_STROBE_PROG_US	10
59 #endif
60 
61 #define BM_READ_CTRL_READ_FUSE		0x00000001
62 
63 #define BF(value, field)		(((value) << BO_##field) & BM_##field)
64 
65 #define WRITE_POSTAMBLE_US		2
66 
67 #if defined(CONFIG_MX6) || defined(CONFIG_VF610)
68 #define FUSE_BANK_SIZE	0x80
69 #ifdef CONFIG_MX6SL
70 #define FUSE_BANKS	8
71 #elif defined(CONFIG_MX6ULL) || defined(CONFIG_MX6SLL)
72 #define FUSE_BANKS	9
73 #else
74 #define FUSE_BANKS	16
75 #endif
76 #elif defined CONFIG_MX7
77 #define FUSE_BANK_SIZE	0x40
78 #define FUSE_BANKS	16
79 #elif defined(CONFIG_MX7ULP)
80 #define FUSE_BANK_SIZE	0x80
81 #define FUSE_BANKS	31
82 #else
83 #error "Unsupported architecture\n"
84 #endif
85 
86 #if defined(CONFIG_MX6)
87 
88 /*
89  * There is a hole in shadow registers address map of size 0x100
90  * between bank 5 and bank 6 on iMX6QP, iMX6DQ, iMX6SDL, iMX6SX,
91  * iMX6UL, i.MX6ULL and i.MX6SLL.
92  * Bank 5 ends at 0x6F0 and Bank 6 starts at 0x800. When reading the fuses,
93  * we should account for this hole in address space.
94  *
95  * Similar hole exists between bank 14 and bank 15 of size
96  * 0x80 on iMX6QP, iMX6DQ, iMX6SDL and iMX6SX.
97  * Note: iMX6SL has only 0-7 banks and there is no hole.
98  * Note: iMX6UL doesn't have this one.
99  *
100  * This function is to covert user input to physical bank index.
101  * Only needed when read fuse, because we use register offset, so
102  * need to calculate real register offset.
103  * When write, no need to consider hole, always use the bank/word
104  * index from fuse map.
105  */
106 u32 fuse_bank_physical(int index)
107 {
108 	u32 phy_index;
109 
110 	if (is_mx6sl() || is_mx7ulp()) {
111 		phy_index = index;
112 	} else if (is_mx6ul() || is_mx6ull() || is_mx6sll()) {
113 		if ((is_mx6ull() || is_mx6sll()) && index == 8)
114 			index = 7;
115 
116 		if (index >= 6)
117 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
118 		else
119 			phy_index = index;
120 	} else {
121 		if (index >= 15)
122 			phy_index = fuse_bank_physical(14) + (index - 15) + 2;
123 		else if (index >= 6)
124 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
125 		else
126 			phy_index = index;
127 	}
128 	return phy_index;
129 }
130 
131 u32 fuse_word_physical(u32 bank, u32 word_index)
132 {
133 	if (is_mx6ull() || is_mx6sll()) {
134 		if (bank == 8)
135 			word_index = word_index + 4;
136 	}
137 
138 	return word_index;
139 }
140 #else
141 u32 fuse_bank_physical(int index)
142 {
143 	return index;
144 }
145 
146 u32 fuse_word_physical(u32 bank, u32 word_index)
147 {
148 	return word_index;
149 }
150 
151 #endif
152 
153 static void wait_busy(struct ocotp_regs *regs, unsigned int delay_us)
154 {
155 	while (readl(&regs->ctrl) & BM_CTRL_BUSY)
156 		udelay(delay_us);
157 }
158 
159 static void clear_error(struct ocotp_regs *regs)
160 {
161 	writel(BM_CTRL_ERROR, &regs->ctrl_clr);
162 }
163 
164 static int prepare_access(struct ocotp_regs **regs, u32 bank, u32 word,
165 				int assert, const char *caller)
166 {
167 	*regs = (struct ocotp_regs *)OCOTP_BASE_ADDR;
168 
169 	if (bank >= FUSE_BANKS ||
170 	    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 2 ||
171 	    !assert) {
172 		printf("mxc_ocotp %s(): Invalid argument\n", caller);
173 		return -EINVAL;
174 	}
175 
176 	if (is_mx6ull() || is_mx6sll()) {
177 		if ((bank == 7 || bank == 8) &&
178 		    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 3) {
179 			printf("mxc_ocotp %s(): Invalid argument\n", caller);
180 			return -EINVAL;
181 		}
182 	}
183 
184 	enable_ocotp_clk(1);
185 
186 	wait_busy(*regs, 1);
187 	clear_error(*regs);
188 
189 	return 0;
190 }
191 
192 static int finish_access(struct ocotp_regs *regs, const char *caller)
193 {
194 	u32 err;
195 
196 	err = !!(readl(&regs->ctrl) & BM_CTRL_ERROR);
197 	clear_error(regs);
198 
199 #ifdef CONFIG_MX7ULP
200 	/* Need to power down the OTP memory */
201 	writel(1, &regs->pdn);
202 #endif
203 	if (err) {
204 		printf("mxc_ocotp %s(): Access protect error\n", caller);
205 		return -EIO;
206 	}
207 
208 	return 0;
209 }
210 
211 static int prepare_read(struct ocotp_regs **regs, u32 bank, u32 word, u32 *val,
212 			const char *caller)
213 {
214 	return prepare_access(regs, bank, word, val != NULL, caller);
215 }
216 
217 int fuse_read(u32 bank, u32 word, u32 *val)
218 {
219 	struct ocotp_regs *regs;
220 	int ret;
221 	u32 phy_bank;
222 	u32 phy_word;
223 
224 	ret = prepare_read(&regs, bank, word, val, __func__);
225 	if (ret)
226 		return ret;
227 
228 	phy_bank = fuse_bank_physical(bank);
229 	phy_word = fuse_word_physical(bank, word);
230 
231 	*val = readl(&regs->bank[phy_bank].fuse_regs[phy_word << 2]);
232 
233 #ifdef CONFIG_MX7ULP
234 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
235 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
236 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
237 		return -EIO;
238 	}
239 #endif
240 	return finish_access(regs, __func__);
241 }
242 
243 #ifdef CONFIG_MX7
244 static void set_timing(struct ocotp_regs *regs)
245 {
246 	u32 ipg_clk;
247 	u32 fsource, prog;
248 	u32 timing;
249 
250 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
251 
252 	fsource = DIV_ROUND_UP((ipg_clk / 1000) * BV_TIMING_FSOURCE_NS,
253 			+       1000000) + 1;
254 	prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_PROG_US, 1000000) + 1;
255 
256 	timing = BF(fsource, TIMING_FSOURCE) | BF(prog, TIMING_PROG);
257 
258 	clrsetbits_le32(&regs->timing, BM_TIMING_FSOURCE | BM_TIMING_PROG,
259 			timing);
260 }
261 #elif defined(CONFIG_MX7ULP)
262 static void set_timing(struct ocotp_regs *regs)
263 {
264 	/* No timing set for MX7ULP */
265 }
266 
267 #else
268 static void set_timing(struct ocotp_regs *regs)
269 {
270 	u32 ipg_clk;
271 	u32 relax, strobe_read, strobe_prog;
272 	u32 timing;
273 
274 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);
275 
276 	relax = DIV_ROUND_UP(ipg_clk * BV_TIMING_RELAX_NS, 1000000000) - 1;
277 	strobe_read = DIV_ROUND_UP(ipg_clk * BV_TIMING_STROBE_READ_NS,
278 					1000000000) + 2 * (relax + 1) - 1;
279 	strobe_prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_STROBE_PROG_US,
280 						1000000) + 2 * (relax + 1) - 1;
281 
282 	timing = BF(strobe_read, TIMING_STROBE_READ) |
283 			BF(relax, TIMING_RELAX) |
284 			BF(strobe_prog, TIMING_STROBE_PROG);
285 
286 	clrsetbits_le32(&regs->timing, BM_TIMING_STROBE_READ | BM_TIMING_RELAX |
287 			BM_TIMING_STROBE_PROG, timing);
288 }
289 #endif
290 
291 static void setup_direct_access(struct ocotp_regs *regs, u32 bank, u32 word,
292 				int write)
293 {
294 	u32 wr_unlock = write ? BV_CTRL_WR_UNLOCK_KEY : 0;
295 #ifdef CONFIG_MX7
296 	u32 addr = bank;
297 #else
298 	u32 addr;
299 	/* Bank 7 and Bank 8 only supports 4 words each for i.MX6ULL */
300 	if ((is_mx6ull() || is_mx6sll()) && (bank > 7)) {
301 		bank = bank - 1;
302 		word += 4;
303 	}
304 	addr = bank << 3 | word;
305 #endif
306 
307 	set_timing(regs);
308 	clrsetbits_le32(&regs->ctrl, BM_CTRL_WR_UNLOCK | BM_CTRL_ADDR,
309 			BF(wr_unlock, CTRL_WR_UNLOCK) |
310 			BF(addr, CTRL_ADDR));
311 }
312 
313 int fuse_sense(u32 bank, u32 word, u32 *val)
314 {
315 	struct ocotp_regs *regs;
316 	int ret;
317 
318 	ret = prepare_read(&regs, bank, word, val, __func__);
319 	if (ret)
320 		return ret;
321 
322 	setup_direct_access(regs, bank, word, false);
323 	writel(BM_READ_CTRL_READ_FUSE, &regs->read_ctrl);
324 	wait_busy(regs, 1);
325 #ifdef CONFIG_MX7
326 	*val = readl((&regs->read_fuse_data0) + (word << 2));
327 #else
328 	*val = readl(&regs->read_fuse_data);
329 #endif
330 
331 #ifdef CONFIG_MX7ULP
332 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
333 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
334 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
335 		return -EIO;
336 	}
337 #endif
338 
339 	return finish_access(regs, __func__);
340 }
341 
342 static int prepare_write(struct ocotp_regs **regs, u32 bank, u32 word,
343 				const char *caller)
344 {
345 	return prepare_access(regs, bank, word, true, caller);
346 }
347 
348 int fuse_prog(u32 bank, u32 word, u32 val)
349 {
350 	struct ocotp_regs *regs;
351 	int ret;
352 
353 	ret = prepare_write(&regs, bank, word, __func__);
354 	if (ret)
355 		return ret;
356 
357 	setup_direct_access(regs, bank, word, true);
358 #ifdef CONFIG_MX7
359 	switch (word) {
360 	case 0:
361 		writel(0, &regs->data1);
362 		writel(0, &regs->data2);
363 		writel(0, &regs->data3);
364 		writel(val, &regs->data0);
365 		break;
366 	case 1:
367 		writel(val, &regs->data1);
368 		writel(0, &regs->data2);
369 		writel(0, &regs->data3);
370 		writel(0, &regs->data0);
371 		break;
372 	case 2:
373 		writel(0, &regs->data1);
374 		writel(val, &regs->data2);
375 		writel(0, &regs->data3);
376 		writel(0, &regs->data0);
377 		break;
378 	case 3:
379 		writel(0, &regs->data1);
380 		writel(0, &regs->data2);
381 		writel(val, &regs->data3);
382 		writel(0, &regs->data0);
383 		break;
384 	}
385 	wait_busy(regs, BV_TIMING_PROG_US);
386 #else
387 	writel(val, &regs->data);
388 	wait_busy(regs, BV_TIMING_STROBE_PROG_US);
389 #endif
390 	udelay(WRITE_POSTAMBLE_US);
391 
392 #ifdef CONFIG_MX7ULP
393 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
394 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
395 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
396 		return -EIO;
397 	}
398 #endif
399 
400 	return finish_access(regs, __func__);
401 }
402 
403 int fuse_override(u32 bank, u32 word, u32 val)
404 {
405 	struct ocotp_regs *regs;
406 	int ret;
407 	u32 phy_bank;
408 	u32 phy_word;
409 
410 	ret = prepare_write(&regs, bank, word, __func__);
411 	if (ret)
412 		return ret;
413 
414 	phy_bank = fuse_bank_physical(bank);
415 	phy_word = fuse_word_physical(bank, word);
416 
417 	writel(val, &regs->bank[phy_bank].fuse_regs[phy_word << 2]);
418 
419 #ifdef CONFIG_MX7ULP
420 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
421 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
422 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
423 		return -EIO;
424 	}
425 #endif
426 
427 	return finish_access(regs, __func__);
428 }
429