S32K3xx recovery mode with destructive reset.

[StephenYeh]

Hi Sir

I try to use Power_Ip_PerformReset to drive the SW reset, we check the DCMRWP1 bit23 (recovery mode on destructive reset.)
If the Power_Ip_PerformReset reset over 8 times, the S32K3xx will trigger, it needs power off and recovery the status.
I also check the HSE-B FW reference manual which mention this feature enables debug of appliation failures hence avoiding device "bricking"
Would your share how to use this safety method?
Ex: The Host(another ECU) can pull low s32k3xx HW reset pin to low pulse.
if the s32k3xx system have enter the destructive reset cause by FW Set.

[StephenYeh]

Hi David,

I check the RM, 

Application can disable recovery mode entry by Secure BAF after programming bits 23 and 22 of DCM register DCMRWP1.

I check the behavior, I try to disable the whatever the  destructive reset or functional reset by memory setting on debug mode.

But, it can't disable the reset function.

Would you share how to disable destructive reset and functional reset?

BTW, we check that write 0x0F to MC_RGM FREC register to clear the reset counter is workable.

[davidtosenovjan]

Please submit a ticket for support continuance as security question cannot be dealt over public forum.

https://www.nxp.com/support/support:SUPPORTHOME

[davidtosenovjan]

The recovery mode related information is included in RM chapter:
"31.12 Recovery mode sequence"; and "31.15.2 DCM.DCMRWP1".
This feature is enabled by default.

Option 1) Customer can modify DCMRWP1 register to disable this feature. 

Option 2) Customer can write 0x0F to MC_RGM FREC register to clear the reset counter. So the recovery mode is not entered.
If the functional reset occurs before clearing the FREC register, this register is incremented.
If this case occur several times and FREC exceeds the threshold 8, the recovery mode is entered.