"ARM® TrustZone® technology is a system-wide approach to security for a wide array of client and server computing platforms, including handsets, tablets, wearable devices and enterprise systems. Applications enabled by the qsee_is_ns_memory(cmd, cmd.len) returns true
Save the value x held by the secure code in the non-secure memory. next, Access the non-secure memory where the value x will be stored from the non-secure code. I want to do something like this, but after writing a value to non-secure memory with secure code, the value is not retained even if the memory is referenced from non-secure code. PrimeCell® Infrastructure AMBA™ 3 AXI™ TrustZone™ Memory 2. About the AXI TrustZone memory adapter The TZMA, TZMemAdapAxi , is an AMBA-compliant, SoC peripheral that is developed, tested, and licensed by ARM Limited. At SoC design time, it is unlikely that the relative requirements of on-chip secure versus non-secure RAM capacity are known. A SoC design Investigating ARM Cortex® M33 core with TrustZone
TrustZone | TrustZone for Cortex-M – Arm Developer
TrustZone partitioning happens at the physical memory level, so the process-level parts of your question don't really apply. Note that Linux as the non-secure OS can't even see secure memory, so having virtual mappings for inaccessible addresses would be of little use; however the secure OS does have the ability to map both secure and non-secure physical addresses by virtue of the NS bit in TrustZone – Arm Developer TrustZone is used on billions of application processors to protect high-value code and data for diverse use cases including authentication, payment, content protection and enterprise. On application processors, TrustZone is frequently used to provide a security boundary for a GlobalPlatform Trusted Execution Environment. security - Use ARM TrustZone to prevent access to memory
TrustZone is one of many hardware features that can be used to build a “Trusted Execution Environment” (TEE), aiming to provide hardware and memory isolation of code and data from the rest of the operating system. Not all TEEs use TrustZone.
Nov 19, 2016 Arm TrustZone explained - microcontrollertips.com Dec 28, 2017