From fe4eaf58608fbffaf1ec4ce08ca3ec3c9432405f Mon Sep 17 00:00:00 2001 From: Florent Kermarrec Date: Tue, 31 Dec 2019 10:25:51 +0100 Subject: [PATCH] build/lattice/icestorm/add_period_constraint: improve - store period in ns. - pass clocks to_build_pre_pack and do the convertion to MHz there. - improve error message. --- litex/build/lattice/icestorm.py | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/litex/build/lattice/icestorm.py b/litex/build/lattice/icestorm.py index c7857408..9a660261 100644 --- a/litex/build/lattice/icestorm.py +++ b/litex/build/lattice/icestorm.py @@ -29,10 +29,10 @@ def _build_pcf(named_sc, named_pc): # Timing Constraints (in pre_pack file) ------------------------------------------------------------ -def _build_pre_pack(vns, freq_cstrs): +def _build_pre_pack(vns, clocks): r = "" - for sig in freq_cstrs: - r += """ctx.addClock("{}", {})\n""".format(vns.get_name(sig), freq_cstrs[sig]) + for clk, period in clocks.items(): + r += """ctx.addClock("{}", {})\n""".format(vns.get_name(clk), 1e3/period) return r # Yosys/Nextpnr Helpers/Templates ------------------------------------------------------------------ @@ -193,12 +193,9 @@ class LatticeIceStormToolchain: return v_output.ns def add_period_constraint(self, platform, clk, period): - clk_ns = 1e3/period clk.attr.add("keep") if clk in self.clocks: - if clk_ns != self.clocks[clk]: - raise ValueError( - "A period constraint already exists" - "(wanted: {:.2f}ns, got {:.2f}ns)".format( - clk_ns, self.clocks[clk])) - self.clocks[clk] = clk_ns + if period != self.clocks[clk]: + raise ValueError("Clock already constrained to {:.2f}ns, new constraint to {:.2f}ns" + .format(self.clocks[clk], period)) + self.clocks[clk] = period -- 2.30.2