cmd/otp.c

   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 );