ENGR00139215 iMX61 Uboot support blow fuse

1. add force option to blow operation
2. add blown value check
3. add simple validation for zeros returned by 'simple_strtoul' call

Signed-off-by: Ryan QIAN <b32804@freescale.com>

1 files changed, 156 insertions, 0 deletions

diff --git a/common/cmd_imxotp.c b/common/cmd_imxotp.c
new file mode 100644
index 0000000..b976aaa
--- /dev/null
+++ b/common/cmd_imxotp.c
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2010-2011 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <config.h>
+#include <common.h>
+#include <command.h>
+#include <imx_otp.h>
+
+/*
+ * meant to reject most of the zeros return by simple_strtoul call.
+ *
+ */
+int validate_zero_from_simple_strtoul(char *str)
+{
+	int i = 0;
+
+	/* reject negatives */
+	if (str[0] == '-')
+		return -1;
+
+	/* reject no zero initialed */
+	if (str[0] != '0')
+		return -1;
+
+	/* accept zero */
+	if (strlen(str) == 1)
+		return 0;
+
+	/* only accept started with "0x" or "0X" or "00" */
+	if (str[1] != 'x' && str[1] != 'X' && str[1] != '0')
+		return -1;
+
+	/* reject "0x" or "0X" or "00" only */
+	if (strlen(str) == 3)
+		return -1;
+
+	/* only accept all zeros */
+	for (i = 1; i < strlen(str) - 1; i++) {
+		if (str[1] != '0')
+			return -1;
+	}
+	return 0;
+}
+
+int do_imxotp(cmd_tbl_t *cmd_tbl, int flag, int argc, char* argv[])
+{
+	u32 addr, value_read, fused_value, value_to_fuse;
+	int force_to_fuse = 0;
+
+	if (argc < 3) {
+usage:
+		cmd_usage(cmd_tbl);
+		return 1;
+	}
+
+	if (!strcmp(argv[1], "read")) {
+		switch (argc) {
+		case 3:
+			addr = simple_strtoul(argv[2], NULL, 16);
+			if ((addr == 0) &&
+				validate_zero_from_simple_strtoul(argv[2]))
+				goto usage;
+			break;
+		default:
+			goto usage;
+		}
+		printf("Reading fuse at index: 0x%X\n", addr);
+		if (imx_otp_read_one_u32(addr, &value_read))
+			return -1;
+		printf("Fuse at (index: 0x%X) value: 0x%X\n", addr, value_read);
+	} else if (!strcmp(argv[1], "blow")) {
+		if (argc < 4 || argc > 5)
+			goto usage;
+
+		if (!strcmp(argv[2], "--force")) {
+			force_to_fuse = 1;
+			addr = simple_strtoul(argv[3], NULL, 16);
+			if ((addr == 0)
+				  && validate_zero_from_simple_strtoul(argv[3]))
+				goto usage;
+			value_to_fuse = simple_strtoul(argv[4], NULL, 16);
+			if ((value_to_fuse == 0)
+				  && validate_zero_from_simple_strtoul(argv[4]))
+				goto usage;
+		} else {
+			addr = simple_strtoul(argv[2], NULL, 16);
+			if ((addr == 0)
+				  && validate_zero_from_simple_strtoul(argv[2]))
+				goto usage;
+			value_to_fuse = simple_strtoul(argv[3], NULL, 16);
+			if ((value_to_fuse == 0)
+				  && validate_zero_from_simple_strtoul(argv[3]))
+				goto usage;
+		}
+
+		/* show the current value of specified address (fuse index) */
+		if (imx_otp_read_one_u32(addr, &value_read))
+			return -1;
+		printf("Current fuse at (index: 0x%X) value: 0x%X\n",
+				addr, value_read);
+
+		if ((value_to_fuse & value_read) == value_to_fuse)
+			printf("!! Fuse blow skipped:"
+					" the bits have been already set.\n");
+		else if (force_to_fuse) {
+			printf("Blowing fuse at index: 0x%X, value: 0x%X\n",
+					addr, value_to_fuse);
+			if (imx_otp_blow_one_u32(addr,
+					value_to_fuse, &fused_value)) {
+				printf("ERROR: failed to blow fuse"
+					  " at 0x%X with value of 0x%X\n",
+						addr, value_to_fuse);
+			} else {
+				printf("Operation %s fuse"
+					  " at (index: 0x%X) value: 0x%X\n",
+					((fused_value & value_to_fuse) ==
+					     value_to_fuse) ? "succeeded"
+										: "failed",
+					addr, fused_value);
+			}
+		} else {
+			printf("!! Fuse blow aborted."
+				" if you do want to blow it."
+				" Please use the command:\n"
+				"%s blow --force %X %X\n",
+				argv[0], addr, value_to_fuse);
+		}
+	} else
+		goto usage;
+
+	return 0;
+}
+
+U_BOOT_CMD(imxotp, 5, 0, do_imxotp,
+	"One-Time Programable sub-system",
+	"imxotp read <addr>\n"
+	" - read fuse at 'addr'\n"
+	"imxotp blow [--force] <addr> <value>\n"
+	" - blow fuse at 'addr' with hex value 'value'\n"
+);