diff --git a/overlay/default.nix b/overlay/default.nix
index fb66e97..87fd898 100644
--- a/overlay/default.nix
+++ b/overlay/default.nix
@@ -1,4 +1,22 @@
-final: prev: {
+final: prev:
+let
+  rpi-kernel = { kernel, version, fw }:
+    let
+      new-kernel = prev.linux_rpi4.override {
+        argsOverride = {
+          src = kernel;
+          inherit version;
+          modDirVersion = version;
+        };
+      };
+      new-fw = prev.raspberrypifw.overrideAttrs (oldfw: { src = fw; });
+      version-slug = builtins.replaceStrings [ "." ] [ "_" ] version;
+    in {
+      "linux_rpi-${version-slug}" = new-kernel;
+      "raspberrypifw-${version-slug}" = new-fw;
+    };
+  rpi-kernels = builtins.foldl' (b: a: b // rpi-kernel a) { };
+in {
   # newer version of libcamera
   libcamera = prev.libcamera.overrideAttrs (old: {
     src = prev.fetchgit {
@@ -12,40 +30,48 @@ final: prev: {
 
   libcamera-apps = final.callPackage ./libcamera-apps.nix { };
 
-  # newer version of rpi firmware
-  raspberrypifw = prev.raspberrypifw.overrideAttrs (old: {
-    src = prev.fetchFromGitHub {
-      owner = "raspberrypi";
-      repo = "firmware";
-      rev = "2cf8a179b3f2e6e5e5ceba4e8e544def10a49020";
-      sha256 = "YG1bryflbV3W62MhZ/XMSgUJXMhCl/fe86x+CT7XZ4U=";
-    };
-  });
-
   # provide generic rpi arm64 u-boot
   uboot_rpi_arm64 = prev.buildUBoot rec {
     defconfig = "rpi_arm64_defconfig";
     extraMeta.platforms = [ "aarch64-linux" ];
     filesToInstall = [ "u-boot.bin" ];
-    version = "2022.04";
+    version = "2022.07";
     src = prev.fetchurl {
       url = "ftp://ftp.denx.de/pub/u-boot/u-boot-${version}.tar.bz2";
-      sha256 = "1l5w13dznj0z1ibqv2d6ljx2ma1gnf5x5ay3dqkqwxr6750nbq38";
+      sha256 = "0png7p8k6rwbmmcyhc22xczcaz7kx0dafw5zmp0i9ni4kjs8xc4j";
     };
   };
-
-  # use a newer version of the rpi linux kernel fork
-  linux_rpi = prev.linux_rpi4.override {
-    argsOverride = rec {
-      src = prev.fetchFromGitHub {
-        owner = "raspberrypi";
-        repo = "linux";
-        rev = "9af1cc301e4dffb830025207a54d0bc63bec16c7";
-        sha256 = "fsMTUdz1XZhPaSXpU1uBV4V4VxoZKi6cwP0QJcrCy1o=";
-        fetchSubmodules = true;
-      };
-      version = "5.15.36";
-      modDirVersion = "5.15.36";
+} // (rpi-kernels [
+  {
+    version = "5.15.36";
+    kernel = prev.fetchFromGitHub {
+      owner = "raspberrypi";
+      repo = "linux";
+      rev = "9af1cc301e4dffb830025207a54d0bc63bec16c7";
+      sha256 = "fsMTUdz1XZhPaSXpU1uBV4V4VxoZKi6cwP0QJcrCy1o=";
+      fetchSubmodules = true;
     };
-  };
-}
+    fw = prev.fetchFromGitHub {
+      owner = "raspberrypi";
+      repo = "firmware";
+      rev = "2cf8a179b3f2e6e5e5ceba4e8e544def10a49020";
+      sha256 = "YG1bryflbV3W62MhZ/XMSgUJXMhCl/fe86x+CT7XZ4U=";
+    };
+  }
+  {
+    version = "5.15.56";
+    kernel = prev.fetchFromGitHub {
+      owner = "raspberrypi";
+      repo = "linux";
+      rev = "912b039b7c55d40ae930f2602e45c66055c375a8";
+      sha256 = "igtTOPbDw9FJAzZe7u4trCkHLOIQX0RZdUwtWpBX1Ag=";
+      fetchSubmodules = true;
+    };
+    fw = prev.fetchFromGitHub {
+      owner = "raspberrypi";
+      repo = "firmware";
+      rev = "e1e3dc004ec45c0a6ab3f32eb02c1e0c8846796c";
+      sha256 = "Smn3wQ81zzmj+Wpt2Xwby+0Zt7YGhmhlaEscbaZaMmI=";
+    };
+  }
+])
diff --git a/rpi/default.nix b/rpi/default.nix
index 26e6750..1df7e01 100644
--- a/rpi/default.nix
+++ b/rpi/default.nix
@@ -13,7 +13,7 @@
 
   nixpkgs = { overlays = [ overlay ]; };
   boot = {
-    kernelPackages = pkgs.linuxPackagesFor (pkgs.linux_rpi);
+    kernelPackages = pkgs.linuxPackagesFor (pkgs.linux_rpi-5_15_56);
     initrd.availableKernelModules = [ "usbhid" "usb_storage" "vc4" ];
 
     loader = {
diff --git a/sd-image/default.nix b/sd-image/default.nix
index 66b3a9e..0977461 100644
--- a/sd-image/default.nix
+++ b/sd-image/default.nix
@@ -17,6 +17,7 @@ stable:
 
   sdImage = {
     populateFirmwareCommands = let
+      raspberrypifw = pkgs.raspberrypifw-5_15_56;
       configTxt = pkgs.writeText "config.txt" ''
         [pi02]
         kernel=u-boot-rpi_arm64.bin
@@ -48,7 +49,7 @@ stable:
         avoid_warnings=1
       '';
     in ''
-      (cd ${pkgs.raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/firmware/)
+      (cd ${raspberrypifw}/share/raspberrypi/boot && cp bootcode.bin fixup*.dat start*.elf $NIX_BUILD_TOP/firmware/)
 
       # Add the config
       cp ${configTxt} firmware/config.txt
@@ -57,16 +58,16 @@ stable:
       cp ${pkgs.uboot_rpi_arm64}/u-boot.bin firmware/u-boot-rpi_arm64.bin
 
       # Add pi3 specific files
-      cp ${pkgs.raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-3-b-plus.dtb firmware/
+      cp ${raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-3-b-plus.dtb firmware/
 
       # Add pi4 specific files
       cp ${pkgs.ubootRaspberryPi4_64bit}/u-boot.bin firmware/u-boot-rpi4.bin
       cp ${pkgs.raspberrypi-armstubs}/armstub8-gic.bin firmware/armstub8-gic.bin
-      cp ${pkgs.raspberrypifw}/share/raspberrypi/boot/bcm2711-rpi-4-b.dtb firmware/
+      cp ${raspberrypifw}/share/raspberrypi/boot/bcm2711-rpi-4-b.dtb firmware/
 
       # Add pi-zero-2 specific files
-      cp ${pkgs.raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-zero-2.dtb firmware/
-      cp ${pkgs.raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-zero-2-w.dtb firmware/
+      cp ${raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-zero-2.dtb firmware/
+      cp ${raspberrypifw}/share/raspberrypi/boot/bcm2710-rpi-zero-2-w.dtb firmware/
     '';
     populateRootCommands = ''
       mkdir -p ./files/boot