export ARCH=arm
export CROSS_COMPILE=/home/sauro/tegra/T30/linux/l4t_15beta/Linux_for_Tegra/kernel/_out/3rdparty/arm-2009q1/bin/arm-none-linux-gnueabi-
export INSTALL_MOD_PATH=/targetfs_l4t_t30_r15_beta

make mrproper
make tegra3_carma_defconfig (tegra3_defconfig is the original for cardhu)
make
make modules_install (copy modules to INSTALL_MOD_PATH)

# to create uImage for u-boot
/home/sauro/tegra/T30/linux/l4t_15beta/Linux_for_Tegra/bootloader/mkimage -A arm -O linux -T kernel -C none -a 0x81008000 -e 0x81008000 -n tegra_l4t -d arch/arm/boot/zImage /tftpboot/uImage_l4t_3.1.10.seco.r15_beta