Based on broadcom official repository: https://github.com/Broadcom/stblinux-4.9/commit/64a3cb2c923f49854402490fae4fb38ba8894e72

Build:

• wget --no-check-certificate -t6 -T20 -c https://github.com/Broadcom/stbgcc-6.3/releases/download/stbgcc-6.3-1.2/stbgcc-6.3-1.2.i386.tar.bz2 -P /opt/toolchains
• tar -xvjf /opt/toolchains/stbgcc-6.3-1.2.i386.tar.bz2 -C /opt/toolchains
• export ARCH=arm
• export PATH=/opt/toolchains/stbgcc-6.3-1.2/bin:$PATH
• export CROSS_COMPILE=arm-linux-gnu-
• make defaults-7278b1
• make images -j8
• cd images
• tar -cvf vmlinuz-initrd_vuduo4k_$(date +%Y%m%d).tar vmlinuz-initrd-7278b1
• gzip vmlinuz-initrd_vuduo4k_$(date +%Y%m%d).tar