Add directions for installation of simulator.

* Add directions for environment setup.
* Add directions to run simple simulation.

Change-Id: I37ed29f58eb9e648feed56f666b750c15f5fa4fb

GettingStarted.md

diff --git a/GettingStarted.md b/GettingStarted.md
index 55f132f..c476a69 100644
--- a/GettingStarted.md
+++ b/GettingStarted.md
@@ -41,6 +41,35 @@
 repo sync -j$(nproc)
 ```
 
+## System Setup for Development
+
+Development for shodan requires that the necessary tools and prerequisites be
+installed.
+
+To setup the build system:
+
+```
+source build/setup.sh
+```
+
+Install the prerequisites:
+
+```
+m prereqs
+```
+
+Install the RISCV toolchain:
+
+```
+m toolchain
+```
+
+Install the instruction set simulator:
+
+```
+m sim
+```
+
 ## Day-to-day Development Workflow
 
 In general, working with repo is relatively simple:
@@ -120,6 +149,30 @@
 
 Contains utility scripts to help automate a few things.
 
+#### sim/
+
+Contains tools and src for simulation of the shodan hw.
+
+## Start a simulation
+
+The simulator used for Shodan is [Renode](https://renode.io/).
+After building and installing the simulator it can be run
+by using the alias `renode`.
+
+This alias is equivalent to the command:
+
+```
+mono cache/renode/Renode.exe
+```
+
+The configuration for the Shodan SoC is `sim/config/shodan.repl`,
+and an example of running zephyr on Shodan can be run as below:
+
+```
+include @sim/config/shodan_zephyr.resc
+start
+```
+
 ## More Information
 
   - [Information on how to use repo](https://go/repo)