[ECOS] How to enable npe support for ixdp425 board?

[Jason Geng]

Hello, everyone. I am now working on RedBoot for a ixdp425 board 
trying to make it able to use the embedded npe ethernet device 
instead of intel 82559 NIC. I use the following shell script to 
build my redboot.bin:
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export ROOTDIR=/test/redboot_root
export TOPDIR=${ROOTDIR}/topdir
export ECOS_REPOSITORY=${TOPDIR}/packages
export VERSION=current

mkdir ${TOPDIR}/build
cd ${TOPDIR}/build

#build ecosconfig
../packages/ecosadmin.tcl add ${ROOTDIR}/npe-1.0.epk
../host/configure
make
cp -f tools/configtool/standalone/common/ecosconfig ../packages/

#construct build tree
../packages/ecosconfig new ixdp425 redboot
../packages/ecosconfig import    \
   ../packages/hal/arm/xscale/ixdp425/current/misc/redboot_RAM.ecm
../packages/ecosconfig add intel_npe
../packages/ecosconfig add ixdp425_npe
../packages/ecosconfig tree

#make redboot.bin
make
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But when I load the RAM version redboot.bin, it reports:
"No network device found." Who can help me about this?