PendSV target secure state

Hi,

As we know, PendSV can be used for context switching, for example in RTOS and software in non-secure state typicall trigger the non-secure PendSV handler.

However, whether we can make the RTOS triggers the secure PendSV handler to process some logics regarding to security purposes and then return to non-secure PendSV handler to process the normal context switching?

Thanks. 

  • Hi Jiameng,

    As per Armv8-M architecture, PendSV exception is banked between security states.

    A secure software can program AIRCR.PRIS bit such that non-secure exceptions are forcibly made to have lower priority than the lowest priority secure exception. Hence a secure exception always gets triggered before non-secure exception when pended.

    Thanks,

    Uma

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