diff --git a/buildroot/COPYING b/buildroot/COPYING
new file mode 100644
index 0000000..8bb257a
--- /dev/null
+++ b/buildroot/COPYING
@@ -0,0 +1,31 @@
+The files "board/litex_vexriscv/linux.config" and
+"configs/litex_vexriscv_defconfig" incorporate code from
+    https://github.com/litex-hub/linux-on-litex-vexriscv
+________________________________________________________________________
+
+BSD 2-Clause License
+
+Copyright (c) 2019-2021, Linux-on-LiteX-VexRiscv Developers
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
diff --git a/buildroot/Config.in b/buildroot/Config.in
new file mode 100644
index 0000000..e69de29
diff --git a/buildroot/board/litex_vexriscv/linux.config b/buildroot/board/litex_vexriscv/linux.config
new file mode 100644
index 0000000..9c3dc11
--- /dev/null
+++ b/buildroot/board/litex_vexriscv/linux.config
@@ -0,0 +1,70 @@
+CONFIG_SECTION_MISMATCH_WARN_ONLY=y
+
+# Architecture
+CONFIG_ARCH_DEFCONFIG="arch/riscv/configs/defconfig"
+CONFIG_NONPORTABLE=y
+CONFIG_ARCH_RV32I=y
+CONFIG_RISCV_ISA_M=y
+CONFIG_RISCV_ISA_A=y
+CONFIG_RISCV_ISA_C=n
+CONFIG_SIFIVE_PLIC=y
+CONFIG_FPU=n
+CONFIG_SMP=n
+CONFIG_STRICT_KERNEL_RWX=n
+CONFIG_EFI=n
+CONFIG_HVC_RISCV_SBI=y
+
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_INITRAMFS_SOURCE=""
+CONFIG_RD_GZIP=y
+
+# FPGA / SoC
+CONFIG_FPGA=y
+CONFIG_FPGA_MGR_LITEX=y
+CONFIG_LITEX_SOC_CONTROLLER=y
+CONFIG_LITEX_SUBREG_SIZE=4
+
+# Time
+CONFIG_PRINTK_TIME=y
+
+# Clocking
+CONFIG_COMMON_CLK=y
+CONFIG_COMMON_CLK_LITEX=y
+
+# Interrupts
+CONFIG_IRQCHIP=y
+CONFIG_OF_IRQ=y
+CONFIG_HANDLE_DOMAIN_IRQ=y
+CONFIG_LITEX_VEXRISCV_INTC=y
+
+# Ethernet
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_PACKET_DIAG=y
+CONFIG_INET=y
+CONFIG_NETDEVICES=y
+CONFIG_NET_VENDOR_LITEX=y
+CONFIG_LITEX_LITEETH=y
+
+# Serial
+CONFIG_SERIAL_EARLYCON_RISCV_SBI=y
+CONFIG_SERIAL_LITEUART=y
+CONFIG_SERIAL_LITEUART_CONSOLE=y
+
+# Hardware monitoring
+CONFIG_HWMON=y
+CONFIG_SENSORS_LITEX_HWMON=y
+
+# Framebuffer
+CONFIG_FB=y
+CONFIG_FB_SIMPLE=y
+CONFIG_FRAMEBUFFER_CONSOLE=y
+CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
+CONFIG_LOGO=y
+
+# .config in kernel
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+
+# Filesystem
+CONFIG_TMPFS=y
diff --git a/buildroot/board/litex_vexriscv/rootfs_overlay/etc/motd b/buildroot/board/litex_vexriscv/rootfs_overlay/etc/motd
new file mode 100644
index 0000000..1f9ff5b
--- /dev/null
+++ b/buildroot/board/litex_vexriscv/rootfs_overlay/etc/motd
@@ -0,0 +1 @@
+Upsilon on Linux, LiteX VexRiscV
diff --git a/buildroot/configs/litex_vexriscv_defconfig b/buildroot/configs/litex_vexriscv_defconfig
new file mode 100644
index 0000000..5e0e14c
--- /dev/null
+++ b/buildroot/configs/litex_vexriscv_defconfig
@@ -0,0 +1,34 @@
+#Target options
+BR2_riscv=y
+BR2_RISCV_32=y
+
+# Instruction Set Extensions
+BR2_riscv_custom=y
+BR2_RISCV_ISA_CUSTOM_RVM=y
+BR2_RISCV_ISA_CUSTOM_RVA=y
+BR2_RISCV_ISA_CUSTOM_RVC=n
+BR2_RISCV_ABI_ILP32=y
+
+# GCC
+BR2_GCC_VERSION_10_X=y
+BR2_BINUTILS_VERSION_2_37_X=y
+
+# System
+BR2_TARGET_GENERIC_GETTY=y
+BR2_TARGET_GENERIC_GETTY_PORT="console"
+
+# Filesystem
+BR2_TARGET_ROOTFS_CPIO=y
+
+# Kernel (litex-rebase branch)
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
+BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="$(BR2_EXTERNAL_UPSILON_PATH)/board/litex_vexriscv/linux.config"
+BR2_LINUX_KERNEL_IMAGE=y
+
+# Rootfs customisation
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_UPSILON_PATH)/board/litex_vexriscv/rootfs_overlay"
+
+# Extra packages
+BR2_PACKAGE_MICROPYTHON=y
+BR2_PACKAGE_MICROPYTHON_LIB=y
diff --git a/buildroot/external.desc b/buildroot/external.desc
new file mode 100644
index 0000000..260b26a
--- /dev/null
+++ b/buildroot/external.desc
@@ -0,0 +1 @@
+name: UPSILON
diff --git a/buildroot/external.mk b/buildroot/external.mk
new file mode 100644
index 0000000..e69de29