2 * cmd_otp.c - interface to Blackfin on-chip One-Time-Programmable memory
4 * Copyright (c) 2007-2008 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
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.
20 #include <asm/blackfin.h>
21 #include <asm/mach-common/bits/otp.h>
23 static const char *otp_strerror(uint32_t err)
26 case 0: return "no error";
27 case OTP_WRITE_ERROR: return "OTP fuse write error";
28 case OTP_READ_ERROR: return "OTP fuse read error";
29 case OTP_ACC_VIO_ERROR: return "invalid OTP address";
30 case OTP_DATA_MULT_ERROR: return "multiple bad bits detected";
31 case OTP_ECC_MULT_ERROR: return "error in ECC bits";
32 case OTP_PREV_WR_ERROR: return "space already written";
33 case OTP_DATA_SB_WARN: return "single bad bit in half page";
34 case OTP_ECC_SB_WARN: return "single bad bit in ECC";
35 default: return "unknown error";
39 #define lowup(x) ((x) % 2 ? "upper" : "lower")
41 static int check_voltage(void)
43 /* Make sure voltage limits are within datasheet spec */
44 uint16_t vr_ctl = bfin_read_VR_CTL();
47 /* 0.9V <= VDDINT <= 1.1V */
48 if ((vr_ctl & 0xc) && (vr_ctl & 0xc0) == 0xc0)
51 /* for the parts w/out qualification yet */
58 static void set_otp_timing(bool write)
60 static uint32_t timing;
62 uint32_t tp1, tp2, tp3;
63 /* OTP_TP1 = 1000 / sclk_period (in nanoseconds)
64 * OTP_TP1 = 1000 / (1 / get_sclk() * 10^9)
65 * OTP_TP1 = (1000 * get_sclk()) / 10^9
66 * OTP_TP1 = get_sclk() / 10^6
68 tp1 = get_sclk() / 1000000;
69 /* OTP_TP2 = 400 / (2 * sclk_period)
70 * OTP_TP2 = 400 / (2 * 1 / get_sclk() * 10^9)
71 * OTP_TP2 = (400 * get_sclk()) / (2 * 10^9)
72 * OTP_TP2 = (2 * get_sclk()) / 10^7
74 tp2 = (2 * get_sclk() / 10000000) << 8;
75 /* OTP_TP3 = magic constant */
77 timing = tp1 | tp2 | tp3;
80 bfrom_OtpCommand(OTP_INIT, write ? timing : timing & ~(-1 << 15));
83 int do_otp(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
85 uint32_t ret, base_flags;
86 bool prompt_user, force_read;
87 uint32_t (*otp_func)(uint32_t page, uint32_t flags, uint64_t *page_content);
97 if (!strcmp(argv[1], "read"))
98 otp_func = bfrom_OtpRead;
99 else if (!strcmp(argv[1], "dump")) {
100 otp_func = bfrom_OtpRead;
102 } else if (!strcmp(argv[1], "write")) {
103 otp_func = bfrom_OtpWrite;
104 base_flags = OTP_CHECK_FOR_PREV_WRITE;
105 if (!strcmp(argv[2], "--force")) {
111 } else if (!strcmp(argv[1], "lock")) {
114 otp_func = bfrom_OtpWrite;
115 base_flags = OTP_LOCK;
119 uint64_t *addr = (uint64_t *)simple_strtoul(argv[2], NULL, 16);
120 uint32_t page = simple_strtoul(argv[3], NULL, 16);
126 count = simple_strtoul(argv[4], NULL, 16);
131 half = simple_strtoul(argv[5], NULL, 16);
132 if (half != 0 && half != 1) {
133 puts("Error: 'half' can only be '0' or '1'\n");
139 /* "otp lock" has slightly different semantics */
140 if (base_flags & OTP_LOCK) {
142 page = (uint32_t)addr;
146 /* do to the nature of OTP, make sure users are sure */
149 "Writing one time programmable memory\n"
150 "Make sure your operating voltages and temperature are within spec\n"
151 " source address: 0x%p\n"
152 " OTP destination: %s page 0x%03X - %s page 0x%03lX\n"
153 " number to write: %lu halfpages\n"
154 " type \"YES\" (no quotes) to confirm: ",
157 lowup(half + count - 1), page + (half + count - 1) / 2,
164 const char exp_ans[] = "YES\r";
167 if (exp_ans[i++] != c) {
168 printf(" Aborting\n");
170 } else if (!exp_ans[i]) {
178 printf("OTP memory %s: addr 0x%p page 0x%03X count %zu ... ",
179 argv[1], addr, page, count);
181 set_otp_timing(otp_func == bfrom_OtpWrite);
182 if (otp_func == bfrom_OtpWrite && check_voltage()) {
183 puts("ERROR: VDDINT voltage is out of spec for writing\n");
187 /* Do the actual reading/writing stuff */
189 for (i = half; i < count + half; ++i) {
190 flags = base_flags | (i % 2 ? OTP_UPPER_HALF : OTP_LOWER_HALF);
192 ret = otp_func(page, flags, addr);
193 if (ret & OTP_MASTER_ERROR) {
195 if (flags & OTP_NO_ECC)
207 if (!(base_flags & OTP_LOCK)) {
215 printf("\nERROR at page 0x%03X (%s-halfpage): 0x%03X: %s\n",
216 page, lowup(i), ret, otp_strerror(ret));
220 /* Make sure we disable writing */
221 set_otp_timing(false);
222 bfrom_OtpCommand(OTP_CLOSE, 0);
227 U_BOOT_CMD(otp, 7, 0, do_otp,
228 "One-Time-Programmable sub-system",
229 "read <addr> <page> [count] [half]\n"
230 " - read 'count' half-pages starting at 'page' (offset 'half') to 'addr'\n"
231 "otp dump <addr> <page> [count] [half]\n"
232 " - like 'otp read', but skip read errors\n"
233 "otp write [--force] <addr> <page> [count] [half]\n"
234 " - write 'count' half-pages starting at 'page' (offset 'half') from 'addr'\n"
235 "otp lock <page> <count>\n"
236 " - lock 'count' pages starting at 'page'"