How do I (cross-)build cgminer for AntMiner S1?
The problem I am trying to solve now is poor scalability of S1 + p2pool (the node and the farm located remotely from each other). Stratum connection results in transfering several kilobytes once per ~30s for every S1 unit simultaneously, which increases latency. At the same time, getwork seems to be broken in current cgminer builds for AntS1 (both stock and latest kano's build), so I want to rebuild and debug it.
First problem in what you are doing:
p2pool and the farm located remotely from each other
Bad idea. P2pool is extremely dependent upon latency due to the excessive restart rate.
Getwork will use way more bandwidth than stratum.
The Getwork in my S1 binary is the Getwork in cgminer - same thing - I'm part of the cgminer team, not a fork.
Your setup is the fault.
Add a proxy if you wish to reduce bandwidth.
Moving away from stratum would only be due to you misunderstanding how the protocols work.
Cross compiling is the same as for the avalon.
Read their info on how to do that ... or the abundant info provided by openwrt.