interface to Blackfin on-chip One-Time-Programmable memory
authorMike Frysinger <vapier@gentoo.org>
Tue, 5 Feb 2008 00:26:57 +0000 (19:26 -0500)
committerMike Frysinger <vapier@gentoo.org>
Tue, 5 Feb 2008 00:26:57 +0000 (19:26 -0500)
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
common/Makefile
common/cmd_otp.c [new file with mode: 0644]

index fbfa536a30c07a4b56d79d069e39e1e296b688a4..3cdab37a4e8f26992c4b13cf549486e0616413dd 100644 (file)
@@ -76,6 +76,7 @@ COBJS-y += cmd_nand.o
 COBJS-$(CONFIG_CMD_NET) += cmd_net.o
 COBJS-y += cmd_nvedit.o
 COBJS-y += cmd_onenand.o
+COBJS-$(CONFIG_CMD_OTP) += cmd_otp.o
 ifdef CONFIG_PCI
 COBJS-$(CONFIG_CMD_PCI) += cmd_pci.o
 endif
diff --git a/common/cmd_otp.c b/common/cmd_otp.c
new file mode 100644 (file)
index 0000000..825fa34
--- /dev/null
@@ -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