xref: /openbmc/u-boot/cmd/otp.c (revision a5c289b9bca3805fa35e42f389dc8225c6b916be)
1  /*
2   * cmd_otp.c - interface to Blackfin on-chip One-Time-Programmable memory
3   *
4   * Copyright (c) 2007-2008 Analog Devices Inc.
5   *
6   * Licensed under the GPL-2 or later.
7   */
8  
9  /* There are 512 128-bit "pages" (0x000 through 0x1FF).
10   * The pages are accessable as 64-bit "halfpages" (an upper and lower half).
11   * The pages are not part of the memory map.  There is an OTP controller which
12   * handles scanning in/out of bits.  While access is done through OTP MMRs,
13   * the bootrom provides C-callable helper functions to handle the interaction.
14   */
15  
16  #include <config.h>
17  #include <common.h>
18  #include <command.h>
19  #include <console.h>
20  
21  #include <asm/blackfin.h>
22  #include <asm/clock.h>
23  #include <asm/mach-common/bits/otp.h>
24  
25  static const char *otp_strerror(uint32_t err)
26  {
27  	switch (err) {
28  	case 0:                   return "no error";
29  	case OTP_WRITE_ERROR:     return "OTP fuse write error";
30  	case OTP_READ_ERROR:      return "OTP fuse read error";
31  	case OTP_ACC_VIO_ERROR:   return "invalid OTP address";
32  	case OTP_DATA_MULT_ERROR: return "multiple bad bits detected";
33  	case OTP_ECC_MULT_ERROR:  return "error in ECC bits";
34  	case OTP_PREV_WR_ERROR:   return "space already written";
35  	case OTP_DATA_SB_WARN:    return "single bad bit in half page";
36  	case OTP_ECC_SB_WARN:     return "single bad bit in ECC";
37  	default:                  return "unknown error";
38  	}
39  }
40  
41  #define lowup(x) ((x) % 2 ? "upper" : "lower")
42  
43  static int check_voltage(void)
44  {
45  	/* Make sure voltage limits are within datasheet spec */
46  	uint16_t vr_ctl = bfin_read_VR_CTL();
47  
48  #ifdef __ADSPBF54x__
49  	/* 0.9V <= VDDINT <= 1.1V */
50  	if ((vr_ctl & 0xc) && (vr_ctl & 0xc0) == 0xc0)
51  		return 1;
52  #else
53  	/* for the parts w/out qualification yet */
54  	(void)vr_ctl;
55  #endif
56  
57  	return 0;
58  }
59  
60  static void set_otp_timing(bool write)
61  {
62  	static uint32_t timing;
63  	if (!timing) {
64  		uint32_t tp1, tp2, tp3;
65  		/* OTP_TP1 = 1000 / sclk_period (in nanoseconds)
66  		 * OTP_TP1 = 1000 / (1 / get_sclk() * 10^9)
67  		 * OTP_TP1 = (1000 * get_sclk()) / 10^9
68  		 * OTP_TP1 = get_sclk() / 10^6
69  		 */
70  		tp1 = get_sclk() / 1000000;
71  		/* OTP_TP2 = 400 / (2 * sclk_period)
72  		 * OTP_TP2 = 400 / (2 * 1 / get_sclk() * 10^9)
73  		 * OTP_TP2 = (400 * get_sclk()) / (2 * 10^9)
74  		 * OTP_TP2 = (2 * get_sclk()) / 10^7
75  		 */
76  		tp2 = (2 * get_sclk() / 10000000) << 8;
77  		/* OTP_TP3 = magic constant */
78  		tp3 = (0x1401) << 15;
79  		timing = tp1 | tp2 | tp3;
80  	}
81  
82  	bfrom_OtpCommand(OTP_INIT, write ? timing : timing & ~(-1 << 15));
83  }
84  
85  int do_otp(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
86  {
87  	char *cmd;
88  	uint32_t ret, base_flags;
89  	bool prompt_user, force_read;
90  	uint32_t (*otp_func)(uint32_t page, uint32_t flags, uint64_t *page_content);
91  
92  	if (argc < 4) {
93   usage:
94  		return CMD_RET_USAGE;
95  	}
96  
97  	prompt_user = false;
98  	base_flags = 0;
99  	cmd = argv[1];
100  	if (!strcmp(cmd, "read"))
101  		otp_func = bfrom_OtpRead;
102  	else if (!strcmp(cmd, "dump")) {
103  		otp_func = bfrom_OtpRead;
104  		force_read = true;
105  	} else if (!strcmp(cmd, "write")) {
106  		otp_func = bfrom_OtpWrite;
107  		base_flags = OTP_CHECK_FOR_PREV_WRITE;
108  		if (!strcmp(argv[2], "--force")) {
109  			argv++;
110  			--argc;
111  		} else
112  			prompt_user = false;
113  	} else if (!strcmp(cmd, "lock")) {
114  		if (argc != 4)
115  			goto usage;
116  		otp_func = bfrom_OtpWrite;
117  		base_flags = OTP_LOCK;
118  	} else
119  		goto usage;
120  
121  	uint64_t *addr = (uint64_t *)simple_strtoul(argv[2], NULL, 16);
122  	uint32_t page = simple_strtoul(argv[3], NULL, 16);
123  	uint32_t flags;
124  	size_t i, count;
125  	ulong half;
126  
127  	if (argc > 4)
128  		count = simple_strtoul(argv[4], NULL, 16);
129  	else
130  		count = 2;
131  
132  	if (argc > 5) {
133  		half = simple_strtoul(argv[5], NULL, 16);
134  		if (half != 0 && half != 1) {
135  			puts("Error: 'half' can only be '0' or '1'\n");
136  			goto usage;
137  		}
138  	} else
139  		half = 0;
140  
141  	/* "otp lock" has slightly different semantics */
142  	if (base_flags & OTP_LOCK) {
143  		count = page;
144  		page = (uint32_t)addr;
145  		addr = NULL;
146  	}
147  
148  	/* do to the nature of OTP, make sure users are sure */
149  	if (prompt_user) {
150  		printf(
151  			"Writing one time programmable memory\n"
152  			"Make sure your operating voltages and temperature are within spec\n"
153  			"   source address:  0x%p\n"
154  			"   OTP destination: %s page 0x%03X - %s page 0x%03lX\n"
155  			"   number to write: %lu halfpages\n"
156  			" type \"YES\" (no quotes) to confirm: ",
157  			addr,
158  			lowup(half), page,
159  			lowup(half + count - 1), page + (half + count - 1) / 2,
160  			half + count
161  		);
162  		if (!confirm_yesno()) {
163  			printf(" Aborting\n");
164  			return 1;
165  		}
166  	}
167  
168  	printf("OTP memory %s: addr 0x%p  page 0x%03X  count %zu ... ",
169  		cmd, addr, page, count);
170  
171  	set_otp_timing(otp_func == bfrom_OtpWrite);
172  	if (otp_func == bfrom_OtpWrite && check_voltage()) {
173  		puts("ERROR: VDDINT voltage is out of spec for writing\n");
174  		return -1;
175  	}
176  
177  	/* Do the actual reading/writing stuff */
178  	ret = 0;
179  	for (i = half; i < count + half; ++i) {
180  		flags = base_flags | (i % 2 ? OTP_UPPER_HALF : OTP_LOWER_HALF);
181   try_again:
182  		ret = otp_func(page, flags, addr);
183  		if (ret & OTP_MASTER_ERROR) {
184  			if (force_read) {
185  				if (flags & OTP_NO_ECC)
186  					break;
187  				else
188  					flags |= OTP_NO_ECC;
189  				puts("E");
190  				goto try_again;
191  			} else
192  				break;
193  		} else if (ret)
194  			puts("W");
195  		else
196  			puts(".");
197  		if (!(base_flags & OTP_LOCK)) {
198  			++addr;
199  			if (i % 2)
200  				++page;
201  		} else
202  			++page;
203  	}
204  	if (ret & 0x1)
205  		printf("\nERROR at page 0x%03X (%s-halfpage): 0x%03X: %s\n",
206  			page, lowup(i), ret, otp_strerror(ret));
207  	else
208  		puts(" done\n");
209  
210  	/* Make sure we disable writing */
211  	set_otp_timing(false);
212  	bfrom_OtpCommand(OTP_CLOSE, 0);
213  
214  	return ret;
215  }
216  
217  U_BOOT_CMD(
218  	otp, 7, 0, do_otp,
219  	"One-Time-Programmable sub-system",
220  	"read <addr> <page> [count] [half]\n"
221  	" - read 'count' half-pages starting at 'page' (offset 'half') to 'addr'\n"
222  	"otp dump <addr> <page> [count] [half]\n"
223  	" - like 'otp read', but skip read errors\n"
224  	"otp write [--force] <addr> <page> [count] [half]\n"
225  	" - write 'count' half-pages starting at 'page' (offset 'half') from 'addr'\n"
226  	"otp lock <page> <count>\n"
227  	" - lock 'count' pages starting at 'page'"
228  );
229