diff --git a/meta-facebook/meta-yosemite4/conf/layer.conf b/meta-facebook/meta-yosemite4/conf/layer.conf
new file mode 100644
index 0000000..0b75f13
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/conf/layer.conf
@@ -0,0 +1,11 @@
+# We have a conf and classes directory, add to BBPATH
+BBPATH .= ":${LAYERDIR}"
+
+# We have recipes-* directories, add to BBFILES
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb \
+            ${LAYERDIR}/recipes-*/*/*.bbappend"
+
+BBFILE_COLLECTIONS += "yosemite4-layer"
+BBFILE_PATTERN_yosemite4-layer := "^${LAYERDIR}/"
+
+LAYERSERIES_COMPAT_yosemite4-layer := "langdale mickledore"
diff --git a/meta-facebook/meta-yosemite4/conf/machine/yosemite4.conf b/meta-facebook/meta-yosemite4/conf/machine/yosemite4.conf
new file mode 100644
index 0000000..038ca35
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/conf/machine/yosemite4.conf
@@ -0,0 +1,21 @@
+KMACHINE = "aspeed"
+#KERNEL_DEVICETREE = "${KMACHINE}-bmc-facebook-${MACHINE}.dtb"
+KERNEL_DEVICETREE = "aspeed-ast2600-evb.dtb"
+
+UBOOT_MACHINE = "ast2600_openbmc_spl_defconfig"
+UBOOT_DEVICETREE = "ast2600-evb"
+SPL_BINARY = "spl/u-boot-spl.bin"
+SOCSEC_SIGN_ENABLE = "0"
+
+require conf/distro/include/phosphor-static-norootfs.inc
+require conf/machine/include/facebook-compute-multihost.inc
+require conf/machine/include/ast2600.inc
+require conf/machine/include/obmc-bsp-common.inc
+require conf/machine/include/facebook-tpm2.inc
+
+FLASH_SIZE = "131072"
+
+OBMC_HOST_INSTANCES = "1 2 3 4 5 6 7 8"
+# Primary chassis as Sled plus secondary chassis in N slots.
+OBMC_CHASSIS_INSTANCES = "0 ${OBMC_HOST_INSTANCES}"
+
diff --git a/meta-facebook/meta-yosemite4/conf/templates/default/bblayers.conf.sample b/meta-facebook/meta-yosemite4/conf/templates/default/bblayers.conf.sample
new file mode 100644
index 0000000..0447cee
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/conf/templates/default/bblayers.conf.sample
@@ -0,0 +1,19 @@
+# LAYER_CONF_VERSION is increased each time build/conf/bblayers.conf
+# changes incompatibly
+LCONF_VERSION = "8"
+
+BBPATH = "${TOPDIR}"
+BBFILES ?= ""
+
+BBLAYERS ?= " \
+  ##OEROOT##/meta \
+  ##OEROOT##/meta-poky \
+  ##OEROOT##/meta-openembedded/meta-oe \
+  ##OEROOT##/meta-openembedded/meta-networking \
+  ##OEROOT##/meta-openembedded/meta-python \
+  ##OEROOT##/meta-security/meta-tpm \
+  ##OEROOT##/meta-phosphor \
+  ##OEROOT##/meta-aspeed \
+  ##OEROOT##/meta-facebook \
+  ##OEROOT##/meta-facebook/meta-yosemite4 \
+  "
diff --git a/meta-facebook/meta-yosemite4/conf/templates/default/conf-notes.txt b/meta-facebook/meta-yosemite4/conf/templates/default/conf-notes.txt
new file mode 100644
index 0000000..9b3c01a
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/conf/templates/default/conf-notes.txt
@@ -0,0 +1,2 @@
+Common targets are:
+     obmc-phosphor-image
diff --git a/meta-facebook/meta-yosemite4/conf/templates/default/local.conf.sample b/meta-facebook/meta-yosemite4/conf/templates/default/local.conf.sample
new file mode 100644
index 0000000..306c66f
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/conf/templates/default/local.conf.sample
@@ -0,0 +1,258 @@
+#
+# This file is your local configuration file and is where all local user settings
+# are placed. The comments in this file give some guide to the options a new user
+# to the system might want to change but pretty much any configuration option can
+# be set in this file. More adventurous users can look at local.conf.extended
+# which contains other examples of configuration which can be placed in this file
+# but new users likely won't need any of them initially.
+#
+# Lines starting with the '#' character are commented out and in some cases the
+# default values are provided as comments to show people example syntax. Enabling
+# the option is a question of removing the # character and making any change to the
+# variable as required.
+
+#
+# Machine Selection
+#
+MACHINE ??= "yosemite4"
+
+#
+# Where to place downloads
+#
+# During a first build the system will download many different source code tarballs
+# from various upstream projects. This can take a while, particularly if your network
+# connection is slow. These are all stored in DL_DIR. When wiping and rebuilding you
+# can preserve this directory to speed up this part of subsequent builds. This directory
+# is safe to share between multiple builds on the same machine too.
+#
+# The default is a downloads directory under TOPDIR which is the build directory.
+#
+#DL_DIR ?= "${TOPDIR}/downloads"
+
+#
+# Where to place shared-state files
+#
+# BitBake has the capability to accelerate builds based on previously built output.
+# This is done using "shared state" files which can be thought of as cache objects
+# and this option determines where those files are placed.
+#
+# You can wipe out TMPDIR leaving this directory intact and the build would regenerate
+# from these files if no changes were made to the configuration. If changes were made
+# to the configuration, only shared state files where the state was still valid would
+# be used (done using checksums).
+#
+# The default is a sstate-cache directory under TOPDIR.
+#
+#SSTATE_DIR ?= "${TOPDIR}/sstate-cache"
+
+#
+# Where to place the build output
+#
+# This option specifies where the bulk of the building work should be done and
+# where BitBake should place its temporary files and output. Keep in mind that
+# this includes the extraction and compilation of many applications and the toolchain
+# which can use Gigabytes of hard disk space.
+#
+# The default is a tmp directory under TOPDIR.
+#
+#TMPDIR = "${TOPDIR}/tmp"
+
+#
+# Default policy config
+#
+# The distribution setting controls which policy settings are used as defaults.
+# The default value is fine for general Yocto project use, at least initially.
+# Ultimately when creating custom policy, people will likely end up subclassing
+# these defaults.
+#
+DISTRO ?= "openbmc-phosphor"
+# As an example of a subclass there is a "bleeding" edge policy configuration
+# where many versions are set to the absolute latest code from the upstream
+# source control systems. This is just mentioned here as an example, its not
+# useful to most new users.
+# DISTRO ?= "poky-bleeding"
+
+#
+# Package Management configuration
+#
+# This variable lists which packaging formats to enable. Multiple package backends
+# can be enabled at once and the first item listed in the variable will be used
+# to generate the root filesystems.
+# Options are:
+#  - 'package_deb' for debian style deb files
+#  - 'package_ipk' for ipk files are used by opkg (a debian style embedded package manager)
+#  - 'package_rpm' for rpm style packages
+# E.g.: PACKAGE_CLASSES ?= "package_rpm package_deb package_ipk"
+# We default to ipk:
+PACKAGE_CLASSES ?= "package_ipk"
+
+#
+# SDK target architecture
+#
+# This variable specifies the architecture to build SDK items for and means
+# you can build the SDK packages for architectures other than the machine you are
+# running the build on (i.e. building i686 packages on an x86_64 host).
+# Supported values are i686, x86_64, aarch64
+#SDKMACHINE ?= "i686"
+
+SANITY_TESTED_DISTROS:append ?= " *"
+
+#
+# Extra image configuration defaults
+#
+# The EXTRA_IMAGE_FEATURES variable allows extra packages to be added to the generated
+# images. Some of these options are added to certain image types automatically. The
+# variable can contain the following options:
+#  "dbg-pkgs"       - add -dbg packages for all installed packages
+#                     (adds symbol information for debugging/profiling)
+#  "src-pkgs"       - add -src packages for all installed packages
+#                     (adds source code for debugging)
+#  "dev-pkgs"       - add -dev packages for all installed packages
+#                     (useful if you want to develop against libs in the image)
+#  "ptest-pkgs"     - add -ptest packages for all ptest-enabled packages
+#                     (useful if you want to run the package test suites)
+#  "tools-sdk"      - add development tools (gcc, make, pkgconfig etc.)
+#  "tools-debug"    - add debugging tools (gdb, strace)
+#  "eclipse-debug"  - add Eclipse remote debugging support
+#  "tools-profile"  - add profiling tools (oprofile, lttng, valgrind)
+#  "tools-testapps" - add useful testing tools (ts_print, aplay, arecord etc.)
+#  "debug-tweaks"   - make an image suitable for development
+#                     e.g. ssh root access has a blank password
+# There are other application targets that can be used here too, see
+# meta/classes/image.bbclass and meta/classes/core-image.bbclass for more details.
+# We default to enabling the debugging tweaks.
+EXTRA_IMAGE_FEATURES ?= "debug-tweaks"
+
+#
+# Additional image features
+#
+# The following is a list of additional classes to use when building images which
+# enable extra features. Some available options which can be included in this variable
+# are:
+#   - 'buildstats' collect build statistics
+USER_CLASSES ?= "buildstats"
+
+#
+# Runtime testing of images
+#
+# The build system can test booting virtual machine images under qemu (an emulator)
+# after any root filesystems are created and run tests against those images. It can also
+# run tests against any SDK that are built. To enable this uncomment these lines.
+# See classes/test{image,sdk}.bbclass for further details.
+#IMAGE_CLASSES += "testimage testsdk"
+#TESTIMAGE_AUTO_qemuall = "1"
+
+#
+# Interactive shell configuration
+#
+# Under certain circumstances the system may need input from you and to do this it
+# can launch an interactive shell. It needs to do this since the build is
+# multithreaded and needs to be able to handle the case where more than one parallel
+# process may require the user's attention. The default is iterate over the available
+# terminal types to find one that works.
+#
+# Examples of the occasions this may happen are when resolving patches which cannot
+# be applied, to use the devshell or the kernel menuconfig
+#
+# Supported values are auto, gnome, xfce, rxvt, screen, konsole (KDE 3.x only), none
+# Note: currently, Konsole support only works for KDE 3.x due to the way
+# newer Konsole versions behave
+#OE_TERMINAL = "auto"
+# By default disable interactive patch resolution (tasks will just fail instead):
+PATCHRESOLVE = "noop"
+
+#
+# Disk Space Monitoring during the build
+#
+# Monitor the disk space during the build. If there is less that 1GB of space or less
+# than 100K inodes in any key build location (TMPDIR, DL_DIR, SSTATE_DIR), gracefully
+# shutdown the build. If there is less than 100MB or 1K inodes, perform a hard abort
+# of the build. The reason for this is that running completely out of space can corrupt
+# files and damages the build in ways which may not be easily recoverable.
+# It's necessary to monitor /tmp, if there is no space left the build will fail
+# with very exotic errors.
+BB_DISKMON_DIRS ??= "\
+    STOPTASKS,${TMPDIR},1G,100K \
+    STOPTASKS,${DL_DIR},1G,100K \
+    STOPTASKS,${SSTATE_DIR},1G,100K \
+    STOPTASKS,/tmp,100M,100K \
+    HALT,${TMPDIR},100M,1K \
+    HALT,${DL_DIR},100M,1K \
+    HALT,${SSTATE_DIR},100M,1K \
+    HALT,/tmp,10M,1K"
+
+#
+# Shared-state files from other locations
+#
+# As mentioned above, shared state files are prebuilt cache data objects which can be
+# used to accelerate build time. This variable can be used to configure the system
+# to search other mirror locations for these objects before it builds the data itself.
+#
+# This can be a filesystem directory, or a remote url such as http or ftp. These
+# would contain the sstate-cache results from previous builds (possibly from other
+# machines). This variable works like fetcher MIRRORS/PREMIRRORS and points to the
+# cache locations to check for the shared objects.
+# NOTE: if the mirror uses the same structure as SSTATE_DIR, you need to add PATH
+# at the end as shown in the examples below. This will be substituted with the
+# correct path within the directory structure.
+#SSTATE_MIRRORS ?= "\
+#file://.* http://someserver.tld/share/sstate/PATH;downloadfilename=PATH \n \
+#file://.* file:///some/local/dir/sstate/PATH"
+
+#
+# Yocto Project SState Mirror
+#
+# The Yocto Project has prebuilt artefacts available for its releases, you can enable
+# use of these by uncommenting the following line. This will mean the build uses
+# the network to check for artefacts at the start of builds, which does slow it down
+# equally, it will also speed up the builds by not having to build things if they are
+# present in the cache. It assumes you can download something faster than you can build it
+# which will depend on your network.
+#
+#SSTATE_MIRRORS ?= "file://.* http://sstate.yoctoproject.org/2.5/PATH;downloadfilename=PATH"
+
+#
+# Qemu configuration
+#
+# By default native qemu will build with a builtin VNC server where graphical output can be
+# seen. The line below enables the SDL UI frontend too.
+PACKAGECONFIG:append:pn-qemu-system-native = " sdl"
+# By default libsdl2-native will be built, if you want to use your host's libSDL instead of
+# the minimal libsdl built by libsdl2-native then uncomment the ASSUME_PROVIDED line below.
+#ASSUME_PROVIDED += "libsdl2-native"
+
+# You can also enable the Gtk UI frontend, which takes somewhat longer to build, but adds
+# a handy set of menus for controlling the emulator.
+#PACKAGECONFIG:append:pn-qemu-system-native = " gtk+"
+
+#
+# Hash Equivalence
+#
+# Enable support for automatically running a local hash equivalence server and
+# instruct bitbake to use a hash equivalence aware signature generator. Hash
+# equivalence improves reuse of sstate by detecting when a given sstate
+# artifact can be reused as equivalent, even if the current task hash doesn't
+# match the one that generated the artifact.
+#
+# A shared hash equivalent server can be set with "<HOSTNAME>:<PORT>" format
+#
+#BB_HASHSERVE = "auto"
+#BB_SIGNATURE_HANDLER = "OEEquivHash"
+
+#
+# Memory Resident Bitbake
+#
+# Bitbake's server component can stay in memory after the UI for the current command
+# has completed. This means subsequent commands can run faster since there is no need
+# for bitbake to reload cache files and so on. Number is in seconds, after which the
+# server will shut down.
+#
+#BB_SERVER_TIMEOUT = "60"
+
+# CONF_VERSION is increased each time build/conf/ changes incompatibly and is used to
+# track the version of this file when it was generated. This can safely be ignored if
+# this doesn't mean anything to you.
+CONF_VERSION = "2"
+
+# Set the root password to '0penBmc'
+# Defaults from meta-phosphor/conf/distro/include/phosphor-defaults.inc
diff --git a/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk/yosemite4.cfg b/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk/yosemite4.cfg
new file mode 100644
index 0000000..1e2a374
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk/yosemite4.cfg
@@ -0,0 +1,3 @@
+CONFIG_USE_BOOTARGS=y
+CONFIG_BOOTARGS="console=ttyS4,57600n8 root=/dev/ram rw vmalloc=768M"
+CONFIG_BAUDRATE=57600
diff --git a/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk_%.bbappend b/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk_%.bbappend
new file mode 100644
index 0000000..a35fc42
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-bsp/u-boot/u-boot-aspeed-sdk_%.bbappend
@@ -0,0 +1,2 @@
+FILESEXTRAPATHS:prepend := "${THISDIR}/${PN}:"
+SRC_URI +="file://yosemite4.cfg"
diff --git a/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed/yosemite4.cfg b/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed/yosemite4.cfg
new file mode 100644
index 0000000..8224a80
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed/yosemite4.cfg
@@ -0,0 +1,41 @@
+# TPM drivers
+CONFIG_TCG_TPM=y
+CONFIG_TCG_TIS_CORE=y
+CONFIG_TCG_TIS=y
+CONFIG_TCG_TIS_SPI=m
+# I2C drivers
+CONFIG_I2C=y
+CONFIG_I2C_SLAVE=y
+# I2C mqueue for mctp
+CONFIG_I2C_SLAVE_MQUEUE=m
+CONFIG_I2C_SLAVE_MQUEUE_QUEUE_SIZE=32
+CONFIG_I2C_SLAVE_MQUEUE_MESSAGE_SIZE=256
+# SPI controller master driver and spi-gpio
+CONFIG_SPI_ASPEED=y
+CONFIG_SPI_GPIO=y
+# Jtag driver
+CONFIG_JTAG=y
+CONFIG_HAS_IOMEM=y
+CONFIG_JTAG_ASPEED=y
+CONFIG_JTAG_ASPEED_LEGACY_UIO=y
+# device driver
+CONFIG_SENSORS_LM75=y
+CONFIG_EEPROM_AT24=y
+CONFIG_SENSORS_ADM1275=y
+CONFIG_I2C_MUX_PCA954x=y
+CONFIG_SENSORS_TMP421=y
+CONFIG_MAX1363=y
+CONFIG_SENSORS_INA238=y
+CONFIG_SENSORS_ADC128D818=y
+CONFIG_SENSORS_MAX31790=y
+CONFIG_GPIO_PCA953X=y
+CONFIG_GPIO_PCA953X_IRQ=y
+CONFIG_LEDS_PCA955X=y
+CONFIG_LEDS_PCA955X_GPIO=y
+# UHCI/EHCI driver
+CONFIG_USB_UHCI_HCD=y
+CONFIG_USB_STORAGE=y
+CONFIG_USB_F_HID=y
+# RTC driver
+CONFIG_RTC_CLASS=y
+CONFIG_RTC_DRV_NCT3018Y=y
diff --git a/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed_%.bbappend b/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed_%.bbappend
new file mode 100644
index 0000000..62623af
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-kernel/linux/linux-aspeed_%.bbappend
@@ -0,0 +1,2 @@
+FILESEXTRAPATHS:prepend := "${THISDIR}/linux-aspeed:"
+SRC_URI += "file://yosemite4.cfg"
diff --git a/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor/virtual_sensor_config.json b/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor/virtual_sensor_config.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor/virtual_sensor_config.json
@@ -0,0 +1 @@
+[]
diff --git a/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor_%.bbappend b/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor_%.bbappend
new file mode 100644
index 0000000..4fc41d0
--- /dev/null
+++ b/meta-facebook/meta-yosemite4/recipes-phosphor/sensors/phosphor-virtual-sensor_%.bbappend
@@ -0,0 +1 @@
+FILESEXTRAPATHS:prepend := "${THISDIR}/${PN}:"
diff --git a/meta-facebook/recipes-phosphor/fans/phosphor-fan/yosemite4/host-poweroff b/meta-facebook/recipes-phosphor/fans/phosphor-fan/yosemite4/host-poweroff
new file mode 100644
index 0000000..b0bbaf6
--- /dev/null
+++ b/meta-facebook/recipes-phosphor/fans/phosphor-fan/yosemite4/host-poweroff
@@ -0,0 +1,27 @@
+#!/bin/bash
+# Power off the hosts when fan sensors crossed thresholds.
+
+echo "Power off the hosts if fansensors threshold crossed ::"
+
+DBUS_SERVICE="xyz.openbmc_project.State.Chassis"
+DBUS_OBJECT="/xyz/openbmc_project/state/chassis"
+DBUS_INTERFACE="xyz.openbmc_project.State.Chassis"
+DBUS_PROPERTY="RequestedPowerTransition"
+PROPERTY_VALUE="xyz.openbmc_project.State.Chassis.Transition.Off"
+
+# Power off the hosts.
+power-off-all-hosts()
+{
+    for host_id in ${HOST_INSTANCES_SED_REPLACEMENT_VALUE}
+    do
+        echo "chosen host id :::$host_id"
+
+        # host power off
+        output=$(busctl set-property $DBUS_SERVICE"$host_id" $DBUS_OBJECT"$host_id" \
+        $DBUS_INTERFACE $DBUS_PROPERTY s $PROPERTY_VALUE)
+        echo "$output"
+
+    done
+}
+
+power-off-all-hosts