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 to 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 #ifdef CONFIG_CMD_OTP
  21
  22 #include <asm/blackfin.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 int do_otp(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
  44 {
  45         bool force = false;
  46         if (!strcmp(argv[1], "--force")) {
  47                 force = true;
  48                 argv[1] = argv[0];
  49                 argv++;
  50                 --argc;
  51         }
  52
  53         uint32_t (*otp_func)(uint32_t page, uint32_t flags, uint64_t *page_content);
  54         if (!strcmp(argv[1], "read"))
  55                 otp_func = otp_read;
  56         else if (!strcmp(argv[1], "write"))
  57                 otp_func = otp_write;
  58         else {
  59  usage:
  60                 printf("Usage:\n%s\n", cmdtp->usage);
  61                 return 1;
  62         }
  63
  64         uint64_t *addr = (uint64_t *)simple_strtoul(argv[2], NULL, 16);
  65         uint32_t page = simple_strtoul(argv[3], NULL, 16);
  66         uint32_t flags, ret;
  67         size_t i, count;
  68         ulong half;
  69
  70         if (argc > 4)
  71                 count = simple_strtoul(argv[4], NULL, 16);
  72         else
  73                 count = 2;
  74
  75         if (argc > 5) {
  76                 half = simple_strtoul(argv[5], NULL, 16);
  77                 if (half != 0 && half != 1) {
  78                         puts("Error: 'half' can only be '0' or '1'\n");
  79                         goto usage;
  80                 }
  81         } else
  82                 half = 0;
  83
  84         /* do to the nature of OTP, make sure users are sure */
  85         if (!force && otp_func == otp_write) {
  86                 printf(
  87                         "Writing one time programmable memory\n"
  88                         "Make sure your operating voltages and temperature are within spec\n"
  89                         "   source address:  0x%p\n"
  90                         "   OTP destination: %s page 0x%03X - %s page 0x%03X\n"
  91                         "   number to write: %ld halfpages\n"
  92                         " type \"YES\" (no quotes) to confirm: ",
  93                         addr,
  94                         lowup(half), page,
  95                         lowup(half + count - 1), page + (half + count - 1) / 2,
  96                         half + count
  97                 );
  98
  99                 i = 0;
 100                 while (1) {
 101                         if (tstc()) {
 102                                 const char exp_ans[] = "YES\r";
 103                                 char c;
 104                                 putc(c = getc());
 105                                 if (exp_ans[i++] != c) {
 106                                         printf(" Aborting\n");
 107                                         return 1;
 108                                 } else if (!exp_ans[i]) {
 109                                         puts("\n");
 110                                         break;
 111                                 }
 112                         }
 113                 }
 114
 115                 /* Only supported in newer silicon ... enable writing */
 116 #if (0)
 117                 otp_command(OTP_INIT, ...);
 118 #else
 119                 *pOTP_TIMING = 0x32149485;
 120 #endif
 121         }
 122
 123         printf("OTP memory %s: addr 0x%08lx  page 0x%03X  count %ld ... ",
 124                 argv[1], addr, page, count);
 125
 126         ret = 0;
 127         for (i = half; i < count + half; ++i) {
 128                 flags = (i % 2) ? OTP_UPPER_HALF : OTP_LOWER_HALF;
 129                 ret = otp_func(page, flags, addr);
 130                 if (ret & 0x1)
 131                         break;
 132                 else if (ret)
 133                         puts("W");
 134                 else
 135                         puts(".");
 136                 ++addr;
 137                 if (i % 2)
 138                         ++page;
 139         }
 140         if (ret & 0x1)
 141                 printf("\nERROR at page 0x%03X (%s-halfpage): 0x%03X: %s\n",
 142                         page, lowup(i), ret, otp_strerror(ret));
 143         else
 144                 puts(" done\n");
 145
 146         if (otp_func == otp_write)
 147                 /* Only supported in newer silicon ... disable writing */
 148 #if (0)
 149                 otp_command(OTP_INIT, ...);
 150 #else
 151                 *pOTP_TIMING = 0x1485;
 152 #endif
 153
 154         return ret;
 155 }
 156
 157 U_BOOT_CMD(otp, 6, 0, do_otp,
 158         "otp - One-Time-Programmable sub-system\n",
 159         "read <addr> <page> [count] [half]\n"
 160         "otp write [--force] <addr> <page> [count] [half]\n"
 161         "    - read/write 'count' half-pages starting at page 'page' (offset 'half')\n");
 162
 163 #endif