辛辛苦苦编译好uboot 要再生成 imx28_ivt_uboot.sb。可按手册上做又出问题，./build命令不对
出错信息为：
by using the pre-build command line
# force building linux_prep
make clean -C linux_prep
make[1]: Entering directory `/jflinux/bootloader/imx-bootlets-src-10.12.01/linux_prep'
Cleaning...
Files:
rm -rf ./core/entry.o ./core/resume.o ./core/cmdlines.o ./core/setup.o ./core/keys.o ./board/iMX28_EVK.o ./hw/lradc-buttons.o ./output-target/linux_prep.ld
Build output:
rm -rf ./output-target
Build system:
rm -rf ./include/arch
make[1]: Leaving directory `/jflinux/bootloader/imx-bootlets-src-10.12.01/linux_prep'
cross-compiling linux_prep
make -C linux_prep ARCH=mx28 BOARD=iMX28_EVK
make[1]: Entering directory `/jflinux/bootloader/imx-bootlets-src-10.12.01/linux_prep'
arm-fsl-linux-gnueabi-gcc -c -Wall -I./include -nostdinc -fno-builtin -O -DMX28 -DBOARD_MX28_EVK -D__ASSEMBLY__ -o core/entry.o core/entry.S
make[1]: arm-fsl-linux-gnueabi-gcc: Command not found
make[1]: *** [core/entry.o] Error 127
make[1]: Leaving directory `/jflinux/bootloader/imx-bootlets-src-10.12.01/linux_prep'
make: *** [linux_prep] Error 2

再次求高人帮忙了！！