Re:Arm Announces Cortex-R82: First 64-Bit Real Time Processor
by recklesstodd on Monday September 07, 2020 @03:42PM
(#24402091)
Another usage for the MMU would be in a virtualization context.
The Hypervisor can configure static address translation tables for each RTOS VM.
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Re:Arm Announces Cortex-R82: First 64-Bit Real Time Processor
by sitkack on Tuesday September 08, 2020 @09:09AM
(#24408004)
The MPU (Memory Protection Unit) in the ARM architecture is like an MVP MMU in that it doesn't have the flexibility of an MMU as the MPU has protection domains (ranges of memory and access semantics bits) and doesn't do address translation like an MMU. It is analogous to mprotect()
I haven't used it, but depending on latency and complexity of updating the MPU config, one could dynamically program it to have an arbitrary levels of protection, think hardware range checks at language level array access.
[1] https://static.docs.arm.com/100699/0100/armv8m_architecture_...