Updated README.md.

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 # MPACT-Cheriot
 
 MPACT-Cheriot is an implementation of an instruction set simulator for the
-CherIoT instruction set architecture created using the MPACT-Sim simulator tools
-and framework and reusing code from MPACT-RiscV.
+[CherIoT](https://cheriot.org) instruction set architecture created using the
+[MPACT-Sim](https://github.com/google/mpact-sim) simulator tools framework and
+reusing code from [MPACT-RiscV](https://github.com/google/mpact-riscv).
+Additional information and codegen tools can be found at
+[https://cheriot.org](https://cheriot.org)
+
+There are three main targets in cheriot/BUILD:
+
+*   mpact_cheriot
+
+    This is the standalone simulator target. It implements a simple command line
+    assembly level debug interface that is accessed by passing the command line
+    option '-i' or '-interactive'.
+
+*   renode_mpact_cheriot
+
+    This produces a shared object, a '.so' file, that can be used together with
+    ReNode, and that is loaded from MpactCheriotCPU.cs plugin file that can be
+    found in mpact_sim:/util/renode/renode_cs. A debug interface can be made
+    available on a socket that you can connect to with telnet or putty. This
+    allows you to step, set breakpoints/watchpoints, etc. while running an
+    application on ReNode.
+
+*   cheriot_test_rig
+
+    This produces an executable suitable for running with TestRIG and comparing
+    against the sail cheriot implementation. For more on that, see the TestRIG
+    documentation.
+
+# Building
+
+MPACT-Cheriot uses the [bazel](https://bazel.build) build system. This is best
+installed using [bazilisk](https://github.com/bazelbuild/bazelisk). Place a file
+named .bazeliskrc in your home directory specifying a bazel version 6.1.1 or
+later:
+
+> USE_BAZEL_VERSION=6.1.1
+
+Once that has been set up, you can build all targets from the top level
+directory using the command `bazel build ...:all`. To run all the tests, use the
+command `bazel test ...:all`.
diff --git a/riscv_cheriot.bin_fmt b/cheriot/riscv_cheriot.bin_fmt
similarity index 100%
rename from riscv_cheriot.bin_fmt
rename to cheriot/riscv_cheriot.bin_fmt
diff --git a/riscv_cheriot.isa b/cheriot/riscv_cheriot.isa
similarity index 100%
rename from riscv_cheriot.isa
rename to cheriot/riscv_cheriot.isa