psa-client-server: move psasim from framework repo to the mbedtls one
This is a temporary fix that will be reverted once the framework
repository will have CI checks.
Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/tests/psa-client-server/psasim/README.md b/tests/psa-client-server/psasim/README.md
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+# psasim
+
+This tool simulates a PSA Firmware Framework implementation.
+It allows you to develop secure partitions and their clients on a desktop computer.
+It should be able to run on all systems that support POSIX and System V IPC:
+e.g. macOS, Linux, FreeBSD, and perhaps Windows 10 WSL2.
+
+Please note that the code in this directory is maintained by the Mbed TLS / PSA Crypto project solely for the purpose of testing the use of Mbed TLS with client/service separation. We do not recommend using this code for any other purpose. In particular:
+
+* This simulator is not intended to pass or demonstrate compliance.
+* This code is only intended for simulation and does not have any security goals. It does not isolate services from clients.
+
+## Building
+
+To build and run the test program make sure you have `make`, `python` and a
+C compiler installed and then enter the following commands:
+
+```sh
+make run
+```
+
+Optionally the `DEBUG=1` command line option can be enabled to increase verbosity:
+
+```sh
+make DEBUG=1 run
+```
+
+Once done with the test, it is possible to clean all the generated files with:
+
+```sh
+make clean
+```
+
+## Features
+
+The implemented API is intended to be compliant with PSA-FF 1.0.0 with the exception of a couple of things that are a work in progress:
+
+* `psa_notify` support
+* "strict" policy in manifest
+
+The only supported "interrupts" are POSIX signals, which act
+as a "virtual interrupt".
+
+The standard PSA RoT APIs are not included (e.g. cryptography, attestation, lifecycle etc).
+
+## Design
+
+The code is designed to be readable rather than fast or secure.
+In this implementation only one message is delivered to a
+RoT service at a time.
+The code is not thread-safe.
+
+## Unsupported features
+
+Because this is a simulator there are a few things that
+can't be reasonably emulated:
+
+* Manifest MMIO regions are unsupported
+* Manifest priority field is ignored
+* Partition IDs are in fact POSIX `pid_t`, which are only assigned at runtime,
+ making it infeasible to populate pid.h with correct values.