Hi,
For Renesas MCUs with TrustZone-M, if it is possible to lock the non-secure MPU (i.e., MPU_NS) configurations? This feature is supported by several ST MCUs such as STM32L552ZE.
Thanks!
Hello,
On Cortex-M33 devices (like RA4M2) which support Trustzone, MMPUSARx registers are write-protected by PRCR.PRC4 bit:
Also registers related to the Bus Master MPU are protected by the PROTECT bit:
I hope this answers your question.
Thanks for your reply.
As far as I know, MMPU is used for confining the memory access of bus masters except for CPU.
Do Cortex-M33 MCUs also support similar register protection for ARM MPU, i.e., the MPU confines processor memory access?
Yes. Again for RA4M2 which has a Cortex-M33:
www.renesas.com/.../ra4m2-group-users-manual-hardware
Thanks.
As presented in RA4M2's documentation, some Master MPU registers are write-protected by the PRCR.PRC4. However, registers of the ARM MPU (which confines CPU memory access) are NOT write-protected by PRCR.PRC4.
Do I understand correctly? Thanks!
Arm MPU registers are defined by Arm and are not described on the RA hardware manual.
For more information and for how they are protected please check the following documents:
I see. Thanks for your kind reply!