update README

add ARM to list of supported platforms and required system environment

README

@@ -11,7 +11,7 @@ version 0.4.0
 
 Last Update
 -----------
-26 February 2021
+3 March 2021
 
 
 Webpages
@@ -21,9 +21,8 @@ https://variorum.readthedocs.io
 
 ## Overview
 
-Variorum provides general interfaces to provide privileged functionality for
-monitoring and controlling various hardware-level features of multiple hardware
-architectures.
+Variorum is an extensible vendor-neutral library for exposing power and
+performance monitoring and control of low-level hardware knobs.
 
 
 ## Documentation
@@ -48,10 +47,10 @@ the installation is as follows:
     $ make install
 ```
 
-Note that Variorum depends on hwloc. The build system will first check for a
-specified local hwloc install, then it will check for a pre-installed hwloc.
-If it can find neither, it will clone and build hwloc from source (will fail on
-machines without internet access).
+Note that Variorum depends on hwloc and JANSSON. The build system will first
+check for a specified local install of these dependencies, then it will check
+if it has been pre-installed. If it can find neither, it will clone and build
+the dependency from source (will fail on machines without internet access).
 
 By default `BUILD_DOCS=ON`, so the build system looks for `Doxygen` and `Sphinx`.
 If you do not want to include these dependencies, simply toggle
@@ -73,14 +72,16 @@ installs. These can be used as follows:
     $ make
 ```
 
-## Platform Support
-Currently supported architectures are Intel Xeons (server processors). The
-library technically supports all Intel processors based on these architectures,
-but some features may vary between platforms.
+## Platform and Microarchitecture Support
+Variorum has support for an increasing number of platforms and
+microarchitectures:
 
-Supported Intel Architectures:
+Platforms supported: Intel, IBM, NVIDIA, ARM
+
+Supported Intel Microarchitectures:
 
     0x2A (Sandy Bridge)
+    0x2D (Sandy Bridge)
     0x3E (Ivy Bridge)
     0x3E (Haswell)
     0x4F (Broadwell)
@@ -90,14 +91,17 @@ Supported Intel Architectures:
 If you are unsure of your architecture number, check the "model" field in `lscpu`
 or `/proc/cpuinfo` (note that it will not be in hexadecimal).
 
-Supported IBM Architectures:
+Supported IBM Microrchitectures:
 
     Power9
 
-Supported Nvidia Architectures:
+Supported Nvidia Microrchitectures:
 
     Volta (requires [CUDA Toolkit[(https://developer.nvidia.com/cuda-downloads))
 
+Supported ARM Microrchitectures:
+
+    Juno r2
 
 ## Testing
 
@@ -139,6 +143,11 @@ present with R/W permissions.
 
 Nvidia: Running this software on Nvidia platforms depends on CUDA being loaded.
 
+ARM: Running this software on ARM platforms depends on the Linux Hardware
+Monitoring (hwmon) subsystem for access to the monitoring and control
+interfaces.
+
+
 ## Bug Tracker
 Bugs and feature requests are being tracked on [GitHub
 Issues](https://github.com/LLNL/variorum/issues).