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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 in Armv8-A .

Please Guide if you know why this happen?

Thank you in advance.

Regards

Sanjay Kumar

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Martin Weidmann over 4 years ago +2

Hi. For background reading I suggest you take a look at the "Boot: Bare Metal" guide linked to from this page: developer.arm.com/.../learn-the-architecture Specifically chapter 5.5, it talks about...

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0 Martin Weidmann over 4 years ago in reply to Mr_Sanjay

Can you share the ELR_EL3, SPSR_EL3 and ESR_EL3 values when execution returns to EL3? Also, what's the address of el2_entry (for comparison to the reported ELR value)?
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0 Martin Weidmann over 4 years ago in reply to Mr_Sanjay

Can you share the ELR_EL3, SPSR_EL3 and ESR_EL3 values when execution returns to EL3? Also, what's the address of el2_entry (for comparison to the reported ELR value)?
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0 Mr_Sanjay over 4 years ago in reply to Martin Weidmann

NO after execution first instruction of EL2 mode, it is remains in EL2 mode only but it goes into unexpected handler..so i cant read EL3 regions registers.
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