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Diffstat (limited to 'common/cmd_otp.c')
| -rw-r--r-- | common/cmd_otp.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/common/cmd_otp.c b/common/cmd_otp.c new file mode 100644 index 0000000..825fa34 --- /dev/null +++ b/common/cmd_otp.c @@ -0,0 +1,163 @@ +/* + * cmd_otp.c - interface to Blackfin on-chip One-Time-Programmable memory + * + * Copyright (c) 2007-2008 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +/* There are 512 128-bit "pages" (0x000 to 0x1FF). + * The pages are accessable as 64-bit "halfpages" (an upper and lower half). + * The pages are not part of the memory map. There is an OTP controller which + * handles scanning in/out of bits. While access is done through OTP MMRs, + * the bootrom provides C-callable helper functions to handle the interaction. + */ + +#include <config.h> +#include <common.h> +#include <command.h> + +#ifdef CONFIG_CMD_OTP + +#include <asm/blackfin.h> +#include <asm/mach-common/bits/otp.h> + +static const char *otp_strerror(uint32_t err) +{ + switch (err) { + case 0: return "no error"; + case OTP_WRITE_ERROR: return "OTP fuse write error"; + case OTP_READ_ERROR: return "OTP fuse read error"; + case OTP_ACC_VIO_ERROR: return "invalid OTP address"; + case OTP_DATA_MULT_ERROR: return "multiple bad bits detected"; + case OTP_ECC_MULT_ERROR: return "error in ECC bits"; + case OTP_PREV_WR_ERROR: return "space already written"; + case OTP_DATA_SB_WARN: return "single bad bit in half page"; + case OTP_ECC_SB_WARN: return "single bad bit in ECC"; + default: return "unknown error"; + } +} + +#define lowup(x) ((x) % 2 ? "upper" : "lower") + +int do_otp(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +{ + bool force = false; + if (!strcmp(argv[1], "--force")) { + force = true; + argv[1] = argv[0]; + argv++; + --argc; + } + + uint32_t (*otp_func)(uint32_t page, uint32_t flags, uint64_t *page_content); + if (!strcmp(argv[1], "read")) + otp_func = otp_read; + else if (!strcmp(argv[1], "write")) + otp_func = otp_write; + else { + usage: + printf("Usage:\n%s\n", cmdtp->usage); + return 1; + } + + uint64_t *addr = (uint64_t *)simple_strtoul(argv[2], NULL, 16); + uint32_t page = simple_strtoul(argv[3], NULL, 16); + uint32_t flags, ret; + size_t i, count; + ulong half; + + if (argc > 4) + count = simple_strtoul(argv[4], NULL, 16); + else + count = 2; + + if (argc > 5) { + half = simple_strtoul(argv[5], NULL, 16); + if (half != 0 && half != 1) { + puts("Error: 'half' can only be '0' or '1'\n"); + goto usage; + } + } else + half = 0; + + /* do to the nature of OTP, make sure users are sure */ + if (!force && otp_func == otp_write) { + printf( + "Writing one time programmable memory\n" + "Make sure your operating voltages and temperature are within spec\n" + " source address: 0x%p\n" + " OTP destination: %s page 0x%03X - %s page 0x%03X\n" + " number to write: %ld halfpages\n" + " type \"YES\" (no quotes) to confirm: ", + addr, + lowup(half), page, + lowup(half + count - 1), page + (half + count - 1) / 2, + half + count + ); + + i = 0; + while (1) { + if (tstc()) { + const char exp_ans[] = "YES\r"; + char c; + putc(c = getc()); + if (exp_ans[i++] != c) { + printf(" Aborting\n"); + return 1; + } else if (!exp_ans[i]) { + puts("\n"); + break; + } + } + } + + /* Only supported in newer silicon ... enable writing */ +#if (0) + otp_command(OTP_INIT, ...); +#else + *pOTP_TIMING = 0x32149485; +#endif + } + + printf("OTP memory %s: addr 0x%08lx page 0x%03X count %ld ... ", + argv[1], addr, page, count); + + ret = 0; + for (i = half; i < count + half; ++i) { + flags = (i % 2) ? OTP_UPPER_HALF : OTP_LOWER_HALF; + ret = otp_func(page, flags, addr); + if (ret & 0x1) + break; + else if (ret) + puts("W"); + else + puts("."); + ++addr; + if (i % 2) + ++page; + } + if (ret & 0x1) + printf("\nERROR at page 0x%03X (%s-halfpage): 0x%03X: %s\n", + page, lowup(i), ret, otp_strerror(ret)); + else + puts(" done\n"); + + if (otp_func == otp_write) + /* Only supported in newer silicon ... disable writing */ +#if (0) + otp_command(OTP_INIT, ...); +#else + *pOTP_TIMING = 0x1485; +#endif + + return ret; +} + +U_BOOT_CMD(otp, 6, 0, do_otp, + "otp - One-Time-Programmable sub-system\n", + "read <addr> <page> [count] [half]\n" + "otp write [--force] <addr> <page> [count] [half]\n" + " - read/write 'count' half-pages starting at page 'page' (offset 'half')\n"); + +#endif |