common/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
  20 #include <asm/blackfin.h>
  21 #include <asm/mach-common/bits/otp.h>
  22
  23 static const char *otp_strerror(uint32_t err)
  24 {
  25         switch (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";
  36         }
  37 }
  38
  39 #define lowup(x) ((x) % 2 ? "upper" : "lower")
  40
  41 static int check_voltage(void)
  42 {
  43         /* Make sure voltage limits are within datasheet spec */
  44         uint16_t vr_ctl = bfin_read_VR_CTL();
  45
  46 #ifdef __ADSPBF54x__
  47         /* 0.9V <= VDDINT <= 1.1V */
  48         if ((vr_ctl & 0xc) && (vr_ctl & 0xc0) == 0xc0)
  49                 return 1;
  50 #else
  51         /* for the parts w/out qualification yet */
  52         (void)vr_ctl;
  53 #endif
  54
  55         return 0;
  56 }
  57
  58 static void set_otp_timing(bool write)
  59 {
  60         static uint32_t timing;
  61         if (!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
  67                  */
  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
  73                  */
  74                 tp2 = (2 * get_sclk() / 10000000) << 8;
  75                 /* OTP_TP3 = magic constant */
  76                 tp3 = (0x1401) << 15;
  77                 timing = tp1 | tp2 | tp3;
  78         }
  79
  80         bfrom_OtpCommand(OTP_INIT, write ? timing : timing & ~(-1 << 15));
  81 }
  82
  83 int do_otp(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  84 {
  85         char *cmd;
  86         uint32_t ret, base_flags;
  87         bool prompt_user, force_read;
  88         uint32_t (*otp_func)(uint32_t page, uint32_t flags, uint64_t *page_content);
  89
  90         if (argc < 4) {
  91  usage:
  92                 return CMD_RET_USAGE;
  93         }
  94
  95         prompt_user = false;
  96         base_flags = 0;
  97         cmd = argv[1];
  98         if (!strcmp(cmd, "read"))
  99                 otp_func = bfrom_OtpRead;
 100         else if (!strcmp(cmd, "dump")) {
 101                 otp_func = bfrom_OtpRead;
 102                 force_read = true;
 103         } else if (!strcmp(cmd, "write")) {
 104                 otp_func = bfrom_OtpWrite;
 105                 base_flags = OTP_CHECK_FOR_PREV_WRITE;
 106                 if (!strcmp(argv[2], "--force")) {
 107                         argv++;
 108                         --argc;
 109                 } else
 110                         prompt_user = false;
 111         } else if (!strcmp(cmd, "lock")) {
 112                 if (argc != 4)
 113                         goto usage;
 114                 otp_func = bfrom_OtpWrite;
 115                 base_flags = OTP_LOCK;
 116         } else
 117                 goto usage;
 118
 119         uint64_t *addr = (uint64_t *)simple_strtoul(argv[2], NULL, 16);
 120         uint32_t page = simple_strtoul(argv[3], NULL, 16);
 121         uint32_t flags;
 122         size_t i, count;
 123         ulong half;
 124
 125         if (argc > 4)
 126                 count = simple_strtoul(argv[4], NULL, 16);
 127         else
 128                 count = 2;
 129
 130         if (argc > 5) {
 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");
 134                         goto usage;
 135                 }
 136         } else
 137                 half = 0;
 138
 139         /* "otp lock" has slightly different semantics */
 140         if (base_flags & OTP_LOCK) {
 141                 count = page;
 142                 page = (uint32_t)addr;
 143                 addr = NULL;
 144         }
 145
 146         /* do to the nature of OTP, make sure users are sure */
 147         if (prompt_user) {
 148                 printf(
 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: ",
 155                         addr,
 156                         lowup(half), page,
 157                         lowup(half + count - 1), page + (half + count - 1) / 2,
 158                         half + count
 159                 );
 160
 161                 i = 0;
 162                 while (1) {
 163                         if (tstc()) {
 164                                 const char exp_ans[] = "YES\r";
 165                                 char c;
 166                                 putc(c = getc());
 167                                 if (exp_ans[i++] != c) {
 168                                         printf(" Aborting\n");
 169                                         return 1;
 170                                 } else if (!exp_ans[i]) {
 171                                         puts("\n");
 172                                         break;
 173                                 }
 174                         }
 175                 }
 176         }
 177
 178         printf("OTP memory %s: addr 0x%p  page 0x%03X  count %zu ... ",
 179                 cmd, addr, page, count);
 180
 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");
 184                 return -1;
 185         }
 186
 187         /* Do the actual reading/writing stuff */
 188         ret = 0;
 189         for (i = half; i < count + half; ++i) {
 190                 flags = base_flags | (i % 2 ? OTP_UPPER_HALF : OTP_LOWER_HALF);
 191  try_again:
 192                 ret = otp_func(page, flags, addr);
 193                 if (ret & OTP_MASTER_ERROR) {
 194                         if (force_read) {
 195                                 if (flags & OTP_NO_ECC)
 196                                         break;
 197                                 else
 198                                         flags |= OTP_NO_ECC;
 199                                 puts("E");
 200                                 goto try_again;
 201                         } else
 202                                 break;
 203                 } else if (ret)
 204                         puts("W");
 205                 else
 206                         puts(".");
 207                 if (!(base_flags & OTP_LOCK)) {
 208                         ++addr;
 209                         if (i % 2)
 210                                 ++page;
 211                 } else
 212                         ++page;
 213         }
 214         if (ret & 0x1)
 215                 printf("\nERROR at page 0x%03X (%s-halfpage): 0x%03X: %s\n",
 216                         page, lowup(i), ret, otp_strerror(ret));
 217         else
 218                 puts(" done\n");
 219
 220         /* Make sure we disable writing */
 221         set_otp_timing(false);
 222         bfrom_OtpCommand(OTP_CLOSE, 0);
 223
 224         return ret;
 225 }
 226
 227 U_BOOT_CMD(
 228         otp, 7, 0, do_otp,
 229         "One-Time-Programmable sub-system",
 230         "read <addr> <page> [count] [half]\n"
 231         " - read 'count' half-pages starting at 'page' (offset 'half') to 'addr'\n"
 232         "otp dump <addr> <page> [count] [half]\n"
 233         " - like 'otp read', but skip read errors\n"
 234         "otp write [--force] <addr> <page> [count] [half]\n"
 235         " - write 'count' half-pages starting at 'page' (offset 'half') from 'addr'\n"
 236         "otp lock <page> <count>\n"
 237         " - lock 'count' pages starting at 'page'"
 238 );