• How to do from Secure(EL3) to Non-secure Exception level transition in ARMV8-A ?

    Hi all i trying do transition from EL3 to EL2 exception ,but after ERET of EL3 mode it change the mode to EL2 , but as soon as when it will execute first instruction of EL2 , then It goes to Exception ...

    This is happen for every secure to non secure transition…

  • how to return from exception generated by SMC instruction

    Hi,

    I am experimenting execution level switching on A53. I go from EL3->El2, then call SMC instruction to return to EL3. As soon as SMC instruction is executed, the processor enters EL3 mode and an exception is generated.

    I have written an exception…

  • how to understand ARMv8 exception level1 secure/non-secure MMU?

    Hi Experts,

         ARMv8 MMU TTBRn_ELx registers are banked by exception level.

         In "DDI0487A_b_armv8_arm.pdf" page 1640, the controlling register of secure EL1&0 stage1 is TTBR0_EL1

         and Non-secure…

  • EL1 behavior when MMU is off

    Hi,

    I am facing issues with EL1 Guest OS.  I have enabled EL2 stage 2 page tables and set up all the virtualization registers {HCR_EL2, VTCR_EL2 and VTTBR_EL2 etc.}

    I am mapping my Guest OS memory to stage 2 tables but as I try to do "eret" from EL2…

  • ELn configuration in ARMV8

    Hi Experts,

    Does the EL3 and EL2 usage is the purely implementation specific or even though EL3 is implemented is it possible to disable EL3 and EL2 in software ?

    Regards,

    Techguyz

  • GICv3 Group0 secure interrupts routed to monitor when running in S-EL1

    Hi,

    In a GICv3 based system, is it possible to have the following configuration:

    While running NS-EL1/EL0:

    -NS Group1 interrupts triggered as IRQ to NS-EL1

    -Secure Grp1 interrupts routed as FIQ to EL3

    -Secure Grp0 interrupts routed as FIQ to EL3

    This…

  • aarch64 Exception Level Sw itch from EL1 to EL0

    Hi Expert,

    I am working on a simple kernel and test it on Qemu which supports RasPi3. During the boot level. Ras Pi goes to EL3 level, and I set spsr_el3 to 1 and elr_el3 to kernel_main and then use eret to enter EL1 mode. My problem is I create a kernel…