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The working secerio is that I'm testing OP-TEE on a Hikey board(Cortex-A53, armv8), and they use arm-trusted-firmware(see https://github.com/linaro-swg/arm-trusted-firmware) to be the monitor running in EL3.
I'm trying to access some resources in EL1 by specifying an virtual memory that would work in EL1, for example, if the address of sys_call_table in EL1 is whatever_the_addr, then I try to access the addr in EL3 directly by using
memcpy(dest, whatever_the_addr, size); //where dest is an array allocated in EL3.
I do the access in the beginning `smc_handler` working in EL3, so that when the EL1 linux kernel launches an SMC instruction(which would be routed to EL3), I do the access.
However, the system just hung up and I couldn't figure out why. I have put the value of TTBR0_EL1 into TTBR0_EL3(which means that their page base registers are the same now), why would the access still fail? Would the SMC call cause some context changes? But I didn't find relevant information in the ARM SMC calling conventions(see http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0028a/index.html).
If I'm not supposed to access it directly, how could I access these memories exactly? Could anyone please give me some clues? I'd appreciate it very much if anyone could help me with it.
BTW, when I decide to access some memory in EL1, the EL1 normal world system has already been running.
Thanks a lot.Tgn