To clarify the three sets of binaries:
-k3: Targets the CPU used by the K2/DX/3, will work on FW 2.x/3.x. (+ 4.x, although I'd recommend the -k5 one for a K4).
-k5: Targets the CPU used by the K4/K5/PW, will work on FW 4.x/5.x
Those are built the exact same way I build my usual stuff.
The -all is a compromise built with my K3 toolchain, it targets the 'older' family of CPU (armv6), but with OpenSSL linked statically (since there's a switch from 0.9.8 to 1.0.0 somewhere in FW 5.0.x) in an attempt to make it run on everything we care about (FW 2.x/3.x/4.x/5.x)
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