Cortex-M33 core SAU->SFAR register not updated when secure fault is entered for a second time

luojia — Wed, 04 May 2022 07:17:49 GMT

Hello!

I'm working with TrustZone code on LPC55S69 chip. In my application I read memory address that would trap into SecureFault which would be recovered using EXC_RETURN. After that my application reads another memory address, resulting in trapping again to SecureFault. I expect SAU->SFAR value changed to the second fault memory address; however when the fault happened, my IDE shows that the value remains in first fault memory address when this trapped SecureFault does not refer to.

I tried to change memory addresses to visit, it always shows that second SAU->SFAR remains in the first memory address, whichever addresses I chose to read to.

How to solve this problem? I'm using LPCXpresso55S69 board, code run on core 0 which has TrustZone technology, and MCUXpresso IDE v11.5.0 version.

Looking forward to replies. Thanks!

Re: Cortex-M33 core SAU->SFAR register not updated when secure fault is entered for a second time

Alice_Yang — Sun, 22 May 2022 07:52:09 GMT

Hello luojia,

Have you check the SDK demo "lpcxpresso55s69_secure_faults " ?

Alice

topic Cortex-M33 core SAU->SFAR register not updated when secure fault is entered for a second time in Kinetis Microcontrollers

Cortex-M33 core SAU->SFAR register not updated when secure fault is entered for a second time

Re: Cortex-M33 core SAU->SFAR register not updated when secure fault is entered for a second time