The i.MX 8M reference manual mentions a JTAG_SMODE[1:0] and a SJC DISABLE e-fuse that are necessary to disable JTAG access. But I can't find the address or location of the fuses. Where can I find them? Is there some document describing it?
已解决! 转到解答。
Here is the description of these fuse bits:
Fuse Address | Fuse Name | Function | Setting |
0x470[21] | SJC_DISABLE | Disable/Enable the Secure JTAG Controller module. This fuse is used to create highest JTAG security level, where JTAG is totally blocked. | 0 - Secure JTAG Controller is enabled 1 - Secure JTAG Controller is disabled |
0x470[23:22] | JTAG_SMODE[1:0] | JTAG Security Mode. Controls the security mode of the JTAG debug interface | 00 - JTAG enable mode 01 - Secure JTAG mode 1x - No debug mode |
Hi,
I have the exact same question, can someone let me know the answer please?
And I agree with what someone else has posted, it is not very useful when the answer results in a private email.
Regards,
Chris
Here is the description of these fuse bits:
Fuse Address | Fuse Name | Function | Setting |
0x470[21] | SJC_DISABLE | Disable/Enable the Secure JTAG Controller module. This fuse is used to create highest JTAG security level, where JTAG is totally blocked. | 0 - Secure JTAG Controller is enabled 1 - Secure JTAG Controller is disabled |
0x470[23:22] | JTAG_SMODE[1:0] | JTAG Security Mode. Controls the security mode of the JTAG debug interface | 00 - JTAG enable mode 01 - Secure JTAG mode 1x - No debug mode |
Meanwhile these fuse bits have been documented in the Security Reference Manuals of 8M Nano and 8M Plus. It's the same structure as in 8M and 8M Mini.
I will check
Regards,
Bernhard.
Hi Christian
one can look at
Understanding how to burn eFuses on i.MX8 and i.MX8x families - i.MXDev Blog
https://community.nxp.com/thread/505184
Best regards
igor
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Hello Igor,
thanks for the reply. My problem is not how to set a fuse in general. It's more the problem where this specific fuses are located.
For example: The reference manual tells me that BT_FUSE_SEL is at 0x470[28] and it tells me that this is bank 1 word 3. But it doesn't tell me a location for JTAG_SMODE[1:0] and SJC DISABLE. For i.MX6 or i.MX7 there is another document that tells me the location (https://www.nxp.com/docs/en/application-note/AN4581.pdf ). But I didn't find one for i.MX8.
Best regards
Christian
Please post the solution here instead of sending it to one single recipient. There are too many threads here that end with "I sent you a mail". The thread is useless for everyone but the thread creator.
I would like to have this information as well.
Thanks,
Marcus
Thanks, igorpadykov, very helpful to answer this by mail!
How about others like us who are also wondering about all this?