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+{{{
+#!htmlcomment
+
+This page is maintained automatically by a script.  Don't modify this page by hand,
+your changes will just be overwritten the next time the script runs.  Talk to your
+Friendly Neighborhood Repository Maintainer if you need to change something here.
+
+}}}
+
+{{{
+#!html
+<h1>releng/alpha</h1>
+
+<p>Release engineering stuff for Cryptech Alpha board and support software.</p>
+
+<h2>Overview</h2>
+
+<p>The Makefiles and scripts in this repository attempt to automate the
+process of building packaged versions of the firmware and software for
+the Cryptech Alpha board.  At a high level, this consists of two main
+phases:</p>
+
+<ol>
+<li><p>Building a firmware package (Verilog and C code which runs on the
+Alpha board itself, regardless the host system to which the Alpha
+is connected); and</p></li>
+<li><p>Building software packages (code which runs on the host to which
+the Alpha is connected).</p></li>
+</ol>
+
+<p>Since the firmware is the same for any given version of the Cryptech
+source code, and since the process of building the firmware binaries
+is both time-consuming and involves tools like the XiLinx Verilog
+synthesis toolkit and cross-compilers for multiple CPUs (the Alpha's
+Cortex M4 ARM CPU and the Atmel AVR ATtiny828 MCU used to implement
+the anti-tampering logic for the master key memory), we include a
+signed tarball containing pre-built binaries for all the firmware as
+part of the source tarball for the software packages.</p>
+
+<p>You are of course free to build all of this for yourself, with or
+without modification, the pre-built versions are just a convenience.</p>
+
+<h2>Source Tree</h2>
+
+<p>The source code itself, for both the firmware and the software, is in
+the source/ directory, with names corresponding to the canonical names
+of the relevant git repositories.  At the time this document was
+written, a few of the repositories in question had not yet been
+promoted to their expected permanent homes in the core/ or sw/ trees,
+but we expect this to be temporary.  Regardless, directory names
+within the source/ directory tree are intended to track the canonical
+names of the git repositories, whatever they may be at any given time.</p>
+
+<h2>Firmware Build Process</h2>
+
+<p>The firmware build process consists of five main phases:</p>
+
+<ol>
+<li><p>Building a "shadow" directory tree populated with symlinks back to
+the source tree.  This allows us to preserve binaries between
+compilation runs where appropriate, without cluttering up the
+source tree with various intermediate files which don't belong
+there.  In particular, this allows to skip the Verilog synthesis
+stage when nothing there has changed, which makes the overall
+build process run significantly faster.</p></li>
+<li><p>Synthesizing the Verilog source code into a bitstream.  This phase
+generates a single bitstream file, suitable for loading into the
+Alpha's FPGA chip.</p></li>
+<li><p>Cross-compiling C code for the Alpha's ARM processor.  This
+produces two images: the bootloader, and the HSM firmware itself.</p></li>
+<li><p>Cross compiling C code for the Alpha's AVR MCU.  This produces a
+single image, which runs the tamper-response controller.</p></li>
+<li><p>Packaging all of the firmware created in the above steps into a
+tarball, with some meta-data describing the package, including
+SHA-2 digests of all of the firmware image files and a signature
+over the entire meta-data block.</p></li>
+</ol>
+
+<p>The precise formats which show up in the firmware tarball are subject
+to change.  At the moment, they consist of:</p>
+
+<ul>
+<li><p>A raw bitstream (".bit" file) for the Xilinx Artix-7 FPGA.</p></li>
+<li><p>ELF and raw binary image files for the Cortex M4 ARM CPU; we supply
+both .elf and .bin files because some tools want one format, some
+want the other.</p></li>
+<li><p>A ".hex" image for the AVR MCU.</p></li>
+</ul>
+
+<p>The overall packaging for the firmware tarball is intentionally pretty
+boring: tar, gzip, gpg, and JSON.  The intent is that users be able to
+use our firmware tarball even if the scripts we provide are unsuitable
+for some reason.</p>
+
+<p>The final result of the firmware build process is the firmware
+tarball, which is written into the source/ tree for inclusion by the
+software packaging phase.</p>
+
+<h2>Software Build Process</h2>
+
+<p>The software build process also consists of several phases, but is a
+bit more open-ended than the firmware build process.  Phases in the
+current build process:</p>
+
+<ol>
+<li><p>Building a source tarball and Debian source package (".dsc").
+The Debian and Ubuntu Linux distributions are our primary
+development platforms, so we need to produce packages for them in
+any case, and the process of producing a Debian-family source
+package produces a source tarball as one of its outputs, so we get
+that for free by doing this step first.</p></li>
+<li><p>Running <a href="https://pbuilder.alioth.debian.org/">pbuilder</a> to generate clean binary packages for the
+"i386" and "amd64" architectures for Debian Jessie and Ubuntu
+Xenial.</p></li>
+<li><p>Loading all of the Debian and Ubuntu packages produced above into
+the staging instances of a set of APT repositories.</p></li>
+<li><p>Generation of a <a href="http://brew.sh/">Homebrew</a> formula and committing that formula to
+the staging instance of a Homebrew "tap" (git repository), using the
+tarball created during the Debian source package stage as the
+source package.  The Homebrew formula is source-only (no "bottled"
+binary packages): creating binary packages would not be
+particularly difficult (one <a href="https://github.com/tpoechtrager/osxcross">osxcross</a> instance per version of
+OSX we want to support would do it), but Apple's Xcode SDK license
+doesn't permit this unless we run our build farm on Apple
+hardware.</p></li>
+<li><p>Uploading changes from the staging repositories to our public
+repositories.</p></li>
+</ol>
+
+<p>In theory, it would also be possible to produce Windows binaries using
+the <a href="http://www.mingw.org/">MinGW</a> cross-compilation environment, but Windows is sufficiently
+different from all other platforms that even minimal Windows support
+would almost certainly require extensive source code changes, so we
+have not put any serious thought into build issues for Windows.</p>
+}}}
+
+[[RepositoryIndex(format=table,glob=releng/alpha)]]
+
+|| Clone `https://git.cryptech.is/releng/alpha.git` ||