diff --git a/tensorflow/workspace.bzl b/tensorflow/workspace.bzl
index 7b9f5d74cf86fb..02879482805e1c 100644
--- a/tensorflow/workspace.bzl
+++ b/tensorflow/workspace.bzl
@@ -156,11 +156,11 @@ def tf_workspace(path_prefix="", tf_repo_name=""):
   native.new_http_archive(
       name = "eigen_archive",
       urls = [
-          "http://mirror.bazel.build/bitbucket.org/eigen/eigen/get/f3a22f35b044.tar.gz",
-          "https://bitbucket.org/eigen/eigen/get/f3a22f35b044.tar.gz",
+          "http://mirror.bazel.build/bitbucket.org/eigen/eigen/get/d781c1de9834.tar.gz",
+          "https://bitbucket.org/eigen/eigen/get/d781c1de9834.tar.gz",
       ],
-      sha256 = "ca7beac153d4059c02c8fc59816c82d54ea47fe58365e8aded4082ded0b820c4",
-      strip_prefix = "eigen-eigen-f3a22f35b044",
+      sha256 = "a34b208da6ec18fa8da963369e166e4a368612c14d956dd2f9d7072904675d9b",
+      strip_prefix = "eigen-eigen-d781c1de9834",
       build_file = str(Label("//third_party:eigen.BUILD")),
   )
 
diff --git a/third_party/toolchains/cpus/arm/CROSSTOOL.tpl b/third_party/toolchains/cpus/arm/CROSSTOOL.tpl
index 7090501dad9308..6753476c153b9b 100644
--- a/third_party/toolchains/cpus/arm/CROSSTOOL.tpl
+++ b/third_party/toolchains/cpus/arm/CROSSTOOL.tpl
@@ -83,6 +83,8 @@ toolchain {
   # explicitly set them as flags. There's a query to the Bazel team outstanding about
   # why this is necessary.
   cxx_flag: "-isystem"
+  cxx_flag: "/usr/include/arm-linux-gnueabihf"
+  cxx_flag: "-isystem"
   cxx_flag: "/usr/include/python2.7"
   cxx_flag: "-isystem"
   cxx_flag: "/usr/include/"
diff --git a/third_party/toolchains/cpus/arm/build_raspberry_pi.sh b/third_party/toolchains/cpus/arm/build_raspberry_pi.sh
index 251a53472a2e6b..a5ad0fce0e4309 100755
--- a/third_party/toolchains/cpus/arm/build_raspberry_pi.sh
+++ b/third_party/toolchains/cpus/arm/build_raspberry_pi.sh
@@ -1,23 +1,39 @@
 #!/usr/bin/env bash
 set -e
 
-# To be able to build any of the python packages, it is assumed that
-# you have a python directory in /usr/include/arm-linux-gnueabihf/.
-
-# To install the architecture includes for python on ubuntu trusty;
-# run:
-#  sudo dpkg --add-architecture armhf
-#  echo "deb [arch=armhf] http://ports.ubuntu.com/ $(lsb_release -s -c) main universe" | \
-#    sudo tee -a /etc/apt/sources.list.d/armhf.list
-#  # Ignore errors about missing armhf packages in other repos.
-#  sudo aptitude update
-#  # Use aptitude; apt-get sometimes runs into errors on this command.
-#  sudo aptitude install libpython-all-dev:armhf python-numpy
+# By default this builds packages for the Pi Two and Three only, since the NEON support
+# this allows makes calculations many times faster. To support the Pi One or Zero, pass
+# PI_ONE as the first argument to the script, for example:
+# third_party/toolchains/cpus/arm/build_raspberry_pi.sh PI_ONE
 #
+# To install the cross-compilation support for Python this script needs on Ubuntu Trusty, run
+# something like these steps, after backing up your original /etc/apt/sources.list file:
+#
+# dpkg --add-architecture armhf
+# echo 'deb [arch=armhf] http://ports.ubuntu.com/ trusty main restricted universe multiverse' >> /etc/apt/sources.list.d/armhf.list
+# echo 'deb [arch=armhf] http://ports.ubuntu.com/ trusty-updates main restricted universe multiverse' >> /etc/apt/sources.list.d/armhf.list
+# echo 'deb [arch=armhf] http://ports.ubuntu.com/ trusty-security main restricted universe multiverse' >> /etc/apt/sources.list.d/armhf.list
+# echo 'deb [arch=armhf] http://ports.ubuntu.com/ trusty-backports main restricted universe multiverse' >> /etc/apt/sources.list.d/armhf.list
+# sed -i 's#deb http://archive.ubuntu.com/ubuntu/#deb [arch=amd64] http://archive.ubuntu.com/ubuntu/#g' /etc/apt/sources.list
+# apt-get update
+# apt-get install -y libpython-all-dev:armhf
+#
+# Make sure you have an up to date version of the Bazel build tool installed too.
 
 yes '' | ./configure
 
-bazel build -c opt --copt=-march=armv6 --copt=-mfpu=vfp \
+if [[ $1 == "PI_ONE" ]]; then
+  PI_COPTS="--copt=-march=armv6 --copt=-mfpu=vfp"
+  echo "Building for the Pi One/Zero, with no NEON support"
+else
+  PI_COPTS='--copt=-march=armv7-a --copt=-mfpu=neon-vfpv4
+  --copt=-U__GCC_HAVE_SYNC_COMPARE_AND_SWAP_1
+  --copt=-U__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2
+  --copt=-U__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8'
+  echo "Building for the Pi Two/Three, with NEON acceleration"
+fi
+
+bazel build -c opt ${PI_COPTS} \
   --copt=-funsafe-math-optimizations --copt=-ftree-vectorize \
   --copt=-fomit-frame-pointer --cpu=armeabi \
   --crosstool_top=@local_config_arm_compiler//:toolchain \