topic Re: TZASC: Protect peripherals other than DRAM in i.MX Processors

TZASC: Protect peripherals other than DRAM

philip-ro — Fri, 14 Apr 2023 08:37:56 GMT

Hi community!

I'm trying to understand how the TZASC works on i.MX6UL.

Can the TZASC protect any memory-mapped peripheral? Only some of them? Or can it only protect DRAM and nothing else?

Best regards,

Philip

Re: TZASC: Protect peripherals other than DRAM

joanxie — Mon, 17 Apr 2023 02:40:43 GMT

Its main feature is to protect security-sensitive software and data in a trusted execution
environment (TEE) against potentially compromised software running on the platform.

For complete details on TZASC and its functionality, please refer to "CoreLink™
TrustZone Address Space Controller TZC-380 Technical Reference Manual”,
available at http://infocenter.arm.com.

Re: TZASC: Protect peripherals other than DRAM

philip-ro — Tue, 18 Apr 2023 06:18:43 GMT

Hi,

I am aware of the RM. I've been trying though, to protect something else than DRAM on my i.MX6UL, i.e. OCRAM or the SNVS address range.

In both cases, despite of the TZASC, the "protected" address ranges can be accessed from the REE.