Ignoring all my detours I did, the sucessfull way for me was
At the end it this is very simple and straight forward, and will take maybe 30 Minutes if you do it right at the first try
>>> ecp5.flashrd(0,32)
bytearray(b'\xff\x00Lattice Semiconductor Corporat')
>>> ecp5.flashrd(0x340000,32)
bytearray(b'3\x04\x05\x00\xb3\x84\x05\x003\t\x06\x00\xef\x00@v3\x08\x05\x003\x05\x04\x00\xb3\x85\x04\x003\x06\t\x00')
>>> ecp5.flashrd(0x380000,32)
bytearray(b'\x13\x02\x05\x00\x93\x84\x05\x00\x97\xc2\x06\x00\x83\xa2\x82\xd9s\x90R\x10s\x10@\x10\x93\x02@\x00cRR"')