+#ifdef CONFIG_ENV_OFFSET_OOB
+unsigned long nand_env_oob_offset;
+
+int do_nand_env_oob(cmd_tbl_t *cmdtp, int argc, char *const argv[])
+{
+ int ret;
+ uint32_t oob_buf[ENV_OFFSET_SIZE/sizeof(uint32_t)];
+ nand_info_t *nand = &nand_info[0];
+ char *cmd = argv[1];
+
+ if (CONFIG_SYS_MAX_NAND_DEVICE == 0 || !nand->name) {
+ puts("no devices available\n");
+ return 1;
+ }
+
+ set_dev(0);
+
+ if (!strcmp(cmd, "get")) {
+ ret = get_nand_env_oob(nand, &nand_env_oob_offset);
+ if (ret)
+ return 1;
+
+ printf("0x%08lx\n", nand_env_oob_offset);
+ } else if (!strcmp(cmd, "set")) {
+ loff_t addr;
+ loff_t maxsize;
+ struct mtd_oob_ops ops;
+ int idx = 0;
+
+ if (argc < 3)
+ goto usage;
+
+ if (arg_off(argv[2], &idx, &addr, &maxsize)) {
+ puts("Offset or partition name expected\n");
+ return 1;
+ }
+
+ if (idx != 0) {
+ puts("Partition not on first NAND device\n");
+ return 1;
+ }
+
+ if (nand->oobavail < ENV_OFFSET_SIZE) {
+ printf("Insufficient available OOB bytes:\n"
+ "%d OOB bytes available but %d required for "
+ "env.oob support\n",
+ nand->oobavail, ENV_OFFSET_SIZE);
+ return 1;
+ }
+
+ if ((addr & (nand->erasesize - 1)) != 0) {
+ printf("Environment offset must be block-aligned\n");
+ return 1;
+ }
+
+ ops.datbuf = NULL;
+ ops.mode = MTD_OOB_AUTO;
+ ops.ooboffs = 0;
+ ops.ooblen = ENV_OFFSET_SIZE;
+ ops.oobbuf = (void *) oob_buf;
+
+ oob_buf[0] = ENV_OOB_MARKER;
+ oob_buf[1] = addr / nand->erasesize;
+
+ ret = nand->write_oob(nand, ENV_OFFSET_SIZE, &ops);
+ if (ret) {
+ printf("Error writing OOB block 0\n");
+ return ret;
+ }
+
+ ret = get_nand_env_oob(nand, &nand_env_oob_offset);
+ if (ret) {
+ printf("Error reading env offset in OOB\n");
+ return ret;
+ }
+
+ if (addr != nand_env_oob_offset) {
+ printf("Verification of env offset in OOB failed: "
+ "0x%08llx expected but got 0x%08lx\n",
+ (unsigned long long)addr, nand_env_oob_offset);
+ return 1;
+ }
+ } else {
+ goto usage;
+ }
+
+ return ret;
+
+usage:
+ return cmd_usage(cmdtp);
+}
+
+#endif
+