PoC: Frigate + PCIe Coral + ESPCam, Home Assistant, ESPHome, MQTT, zigbee2mqtt

overlays/default.nix

@@ -0,0 +1,5 @@
+final: prev:
+
+{
+  libedgetpu = prev.callPackage ./libedgetpu { };
+}

overlays/kernel-modules/default.nix

@@ -0,0 +1,19 @@
+{ config, lib, ... }:
+
+# Adds additional kernel modules to the nixos system
+# Not actually an overlay but a module. Has to be this way because kernel
+# modules are tightly coupled to the kernel version they were built against.
+# https://nixos.wiki/wiki/Linux_kernel
+
+let
+  cfg = config.kernel;
+
+  gasket = config.boot.kernelPackages.callPackage ./gasket.nix { };
+in
+{
+  options.kernel.enableGasketKernelModule = lib.mkEnableOption "Enable Gasket Kernel Module";
+
+  config = lib.mkIf cfg.enableGasketKernelModule {
+    boot.extraModulePackages = [ gasket ];
+  };
+}

overlays/kernel-modules/gasket.nix

@@ -0,0 +1,35 @@
+{ stdenv, lib, fetchFromGitHub, kernel }:
+
+stdenv.mkDerivation rec {
+  pname = "gasket";
+  version = "1.0-18";
+
+  src = fetchFromGitHub {
+    owner = "google";
+    repo = "gasket-driver";
+    rev = "97aeba584efd18983850c36dcf7384b0185284b3";
+    sha256 = "pJwrrI7jVKFts4+bl2xmPIAD01VKFta2SRuElerQnTo=";
+  };
+
+  makeFlags = [
+    "-C"
+    "${kernel.dev}/lib/modules/${kernel.modDirVersion}/build"
+    "M=$(PWD)"
+  ];
+  buildFlags = [ "modules" ];
+
+  installFlags = [ "INSTALL_MOD_PATH=${placeholder "out"}" ];
+  installTargets = [ "modules_install" ];
+
+  sourceRoot = "source/src";
+  hardeningDisable = [ "pic" "format" ];
+  nativeBuildInputs = kernel.moduleBuildDependencies;
+
+  meta = with lib; {
+    description = "The Coral Gasket Driver allows usage of the Coral EdgeTPU on Linux systems.";
+    homepage = "https://github.com/google/gasket-driver";
+    license = licenses.gpl2;
+    maintainers = [ lib.maintainers.kylehendricks ];
+    platforms = platforms.linux;
+  };
+}

overlays/libedgetpu/default.nix

@@ -0,0 +1,72 @@
+{ stdenv
+, lib
+, fetchFromGitHub
+, libusb1
+, abseil-cpp
+, flatbuffers
+, xxd
+}:
+
+let
+  flatbuffers_1_12 = flatbuffers.overrideAttrs (oldAttrs: rec {
+    version = "1.12.0";
+    NIX_CFLAGS_COMPILE = "-Wno-error=class-memaccess -Wno-error=maybe-uninitialized";
+    cmakeFlags = (oldAttrs.cmakeFlags or [ ]) ++ [ "-DFLATBUFFERS_BUILD_SHAREDLIB=ON" ];
+    NIX_CXXSTDLIB_COMPILE = "-std=c++17";
+    configureFlags = (oldAttrs.configureFlags or [ ]) ++ [ "--enable-shared" ];
+    src = fetchFromGitHub {
+      owner = "google";
+      repo = "flatbuffers";
+      rev = "v${version}";
+      sha256 = "sha256-L1B5Y/c897Jg9fGwT2J3+vaXsZ+lfXnskp8Gto1p/Tg=";
+    };
+  });
+
+in
+stdenv.mkDerivation rec {
+  pname = "libedgetpu";
+  version = "grouper";
+
+  src = fetchFromGitHub {
+    owner = "google-coral";
+    repo = pname;
+    rev = "release-${version}";
+    sha256 = "sha256-73hwItimf88Iqnb40lk4ul/PzmCNIfdt6Afi+xjNiBE=";
+  };
+
+  patches = [ ./libedgetpu-stddef.diff ];
+
+  makeFlags = [ "-f" "makefile_build/Makefile" "libedgetpu" ];
+
+  buildInputs = [
+    libusb1
+    abseil-cpp
+    flatbuffers_1_12
+  ];
+
+  nativeBuildInputs = [
+    xxd
+  ];
+
+  NIX_CXXSTDLIB_COMPILE = "-std=c++17";
+
+  TFROOT = "${fetchFromGitHub {
+    owner = "tensorflow";
+    repo = "tensorflow";
+    rev = "v2.7.4";
+    sha256 = "sha256-liDbUAdaVllB0b74aBeqNxkYNu/zPy7k3CevzRF5dk0=";
+  }}";
+
+  enableParallelBuilding = false;
+
+  installPhase = ''
+    mkdir -p $out/lib
+    cp out/direct/k8/libedgetpu.so.1.0 $out/lib
+    ln -s $out/lib/libedgetpu.so.1.0 $out/lib/libedgetpu.so.1
+    mkdir -p $out/lib/udev/rules.d
+    cp debian/edgetpu-accelerator.rules $out/lib/udev/rules.d/99-edgetpu-accelerator.rules
+
+    # PCIe rule
+    echo 'SUBSYSTEM=="apex", MODE="0660", GROUP="apex"' > $out/lib/udev/rules.d/65-apex.rules
+  '';
+}

overlays/libedgetpu/libedgetpu-stddef.diff

@@ -0,0 +1,12 @@
+diff --git a/api/allocated_buffer.h b/api/allocated_buffer.h
+index 97740f0..7bc0547 100644
+--- a/api/allocated_buffer.h
++++ b/api/allocated_buffer.h
+@@ -16,6 +16,7 @@
+ #define DARWINN_API_ALLOCATED_BUFFER_H_
+ 
+ #include <functional>
++#include <cstddef>
+ 
+ namespace platforms {
+ namespace darwinn {