MSPM0L2228: MSPM0L2228

Hi, Deepika Patil

Deepika Patil said:

What register i have to use to get flash secure state?

What's your requirement about this flash secure state?

Can you show me some section in TRM?

https://www.ti.com/lit/pdf/slau847

Or some spec in this document?

https://www.ti.com/lit/an/slaae29/slaae29.pdf

Regards,

Helic

In NXP backdoor access feature is present, that i have to implement in TI.
So for that  need to check:

1. Flash is secure or not.
2. If flash is secure, check the backdoor key is enabled.
3. If it is enabled, perform command write sequence on flash.

Hi, Deepika

Deepika Patil said:

In MSPM0L2228 controller how can i get security state of flash as a secure / not secure?

From my point of view, L2228's internal Flash can be secured.

But we need to dig into basic description, since there are many definition about security.

Deepika Patil said:

1. Flash is secure or not.
2. If flash is secure, check the backdoor key is enabled.
3. If it is enabled, perform command write sequence on flash.

Can you please help clarify the specific details of these features?

From my side, I can tell you that in this document:https://www.ti.com/lit/an/slaae29/slaae29.pdf

There are some Flash security feature that you can check:

It's hard to me to understand [NXP backdoor access feature], since I am a TIer.

Once you check these safety/security feature, if you still have some question, please feel free to ask me.

Hope I can guide you well.

Regards,

Helic

In NXP:
Back door access:
The Verify Backdoor Access Key command is qualified by the
FSEC[KEYEN] bits. The Verify Backdoor Access Key command releases security if
user-supplied keys in the FCCOB match those stored in the Backdoor Comparison Key
bytes of the Flash Configuration Field. The column labeled Flash Configuration Field
offset address shows the location of the matching byte in the Flash Configuration Field.

In FSEC register, check SEC bit(if SEC:1 then flash is not secure, if SEC:0 then flash is secure)
if SEC = 0, then check backdoor access is enable or not with KEYEN bit from FSEC register.
If backdoor access is enable then
check CCIF bit = 0 from FTFC register,if CCIF bit is not clear then Clear RDCOLERR & ACCERR & FPVIOL flag in flash status register. Write 1 to clear
then pass 0x45(backdoor access key) to FCC0B0
then Perform command write sequence on Flash.

Please can you check how this can implement in MSPM0L1228 controller.

Hi, Deepika

Deepika Patil said:

Back door access:

Supported by SWD password.

Please refer to TRM: https://www.ti.com/lit/ug/slau847d/slau847d.pdf

All security you can find description here: Chapter 4 SECURITY

Deepika Patil said:

In FSEC register, check SEC bit(if SEC:1 then flash is not secure, if SEC:0 then flash is secure)

How to define this [Flash is secure].

Only way to access flash in MSPM0 is using SWD debug interface.

We can enable SWD password to protect Flash.

And in TRM, you can find Flash protection function:

Flash write-erase protection

Flash read-execute protection

Flash IP protection.

L2228 also support ECC Flash, there are register that will show the result 1 or 2 bit error in Flash check.

1 bit error will be auto fixed by ECC, and 2 bit error will cause a Flash interrupt.

Regards,

HElic

Thanks for giving this info,
Please can you share that ( there are register that will show the result 1 or 2 bit error) register name to check flash is protected or not.

Regards,

Deepika.

Hi,

Is there any backdoor key bit present in flash? above chain i explain about backdoor.

Thanks,

Deepika.

Hi, Deepika

Sorry, I don't quite understand these description.

Deepika Patil said:

Back door access:
The Verify Backdoor Access Key command is qualified by the
FSEC[KEYEN] bits. The Verify Backdoor Access Key command releases security if
user-supplied keys in the FCCOB match those stored in the Backdoor Comparison Key
bytes of the Flash Configuration Field. The column labeled Flash Configuration Field
offset address shows the location of the matching byte in the Flash Configuration Field.

In FSEC register, check SEC bit(if SEC:1 then flash is not secure, if SEC:0 then flash is secure)
if SEC = 0, then check backdoor access is enable or not with KEYEN bit from FSEC register.
If backdoor access is enable then
check CCIF bit = 0 from FTFC register,if CCIF bit is not clear then Clear RDCOLERR & ACCERR & FPVIOL flag in flash status register. Write 1 to clear
then pass 0x45(backdoor access key) to FCC0B0
then Perform command write sequence on Flash.

Regards,

Helic

Back door access:
The verify backdoor access key command is used to unlock the controller when it is in secure state. This command allow to bypass the security setting without needing to reprogramed the flash configuration field. By using verify backdoor access key command temporirly unsecure the MCU allowing debugging and programming. Once MCU is reset, it will return to its secure state.

HI, Deepika

We don't have this kind of register.

But with security config in non-main (include SWD password, Flash protection, and factory reset control), I don't think this is a necessary function for security.

I recommend you to go through this document firstly: https://www.ti.com/lit/an/slaae29/slaae29.pdf

To see if MSPM0 can meet your requirement.

Regards,

Helic