不久前我移植了u-boot-214-04到Tq2440的板子上，基本功能都有了，网卡也可以使用了。有一天打算把u-boot-2010-06也也一直到tq2440上，移植完后发现u-boot-214-04在tq2440上的网络死活不通了。
通过加打印发现，在u-boot-2014-04上使用ping命令是有如下信息：
Got ARP
packet received
Receive from protocol 0x86dd
packet received
Receive from protocol 0x86dd
packet received
Receive from protocol 0x800
Got IP
len bad 48 < 124
packet received
Receive from protocol 0x86dd
packet received
Receive from protocol 0x800
Got IP
len bad 62 < 125
packet received
Receive from protocol 0x806
Got ARP
packet received
Receive from protocol 0x86dd
packet received
Receive from protocol 0x800
Got IP
len bad 48 < 126
packet received
Receive from protocol 0x86dd
packet received
Receive from protocol 0x800
Got IP
len bad 62 < 127
packet received
Receive from protocol 0x800
Got IP
len=128, v=00
packet received
Receive from protocol 0x800
即收的的包格式不对，总是打印len bad，觉得不应该，用u-boot-2010-06，网络却是好的。最后发现，原来是我在移植u-boot-2014-04时使用的工具链的版本是：
gcc version 4.3.3 (Sourcery G++ Lite 2009q1-176)
但是在移植u-boot-2010-06的时候换成了
gcc version 3.4.5
用3.4.5版本了的工具链编译最新的u-boot，会发生问题。然后我重新换成4.3.3版本的工具链，网络就正常了。
所以，编译最新的u-boot应该用比较新的交叉编译工具链，否则会出现很诡异的问题。
u-boot-2014-04 网络不通解决一例,布布扣,bubuko.com
原文：http://www.cnblogs.com/pengdonglin137/p/3830268.html