diff options
Diffstat (limited to 'passes/pmgen')
| -rw-r--r-- | passes/pmgen/xilinx_dsp.cc | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/passes/pmgen/xilinx_dsp.cc b/passes/pmgen/xilinx_dsp.cc index 8500a6072..5af48e4d2 100644 --- a/passes/pmgen/xilinx_dsp.cc +++ b/passes/pmgen/xilinx_dsp.cc @@ -2,6 +2,7 @@ * yosys -- Yosys Open SYnthesis Suite * * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at> + * 2019 Eddie Hung <eddie@fpgeh.com> * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above @@ -519,6 +520,10 @@ struct XilinxDspPass : public Pass { log("the add/subtract operator will cause those operations to be implemented using\n"); log("the 'SIMD' feature of DSPs.\n"); log("\n"); + log("Experimental feature: the presence of a `$ge' cell attached to the registered\n"); + log("P output implementing the operation \"(P >= <power-of-2>)\" will be transformed\n"); + log("into using the DSP48E1's pattern detector feature for overflow detection.\n"); + log("\n"); } void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE { |