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ecp5: Consider fanout when calculating pip delays

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Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2018-11-15 19:10:31 +00:00
parent cc746d888b
commit 2024346f4d
1 changed files with 12 additions and 2 deletions
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14
ecp5/arch.h
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@ -461,6 +461,7 @@ struct Arch : BaseCtx
std::vector<CellInfo *> bel_to_cell;
std::unordered_map<WireId, NetInfo *> wire_to_net;
std::unordered_map<PipId, NetInfo *> pip_to_net;
std::unordered_map<WireId, int> wire_fanout;
ArchArgs args;
Arch(ArchArgs args);
@ -643,6 +644,7 @@ struct Arch : BaseCtx
auto pip = it->second.pip;
if (pip != PipId()) {
wire_fanout[getPipSrcWire(pip)]--;
pip_to_net[pip] = nullptr;
}
@ -733,6 +735,7 @@ struct Arch : BaseCtx
NPNR_ASSERT(pip_to_net[pip] == nullptr);
pip_to_net[pip] = net;
wire_fanout[getPipSrcWire(pip)]++;
WireId dst;
dst.index = locInfo(pip)->pip_data[pip.index].dst_idx;
@ -747,6 +750,7 @@ struct Arch : BaseCtx
{
NPNR_ASSERT(pip != PipId());
NPNR_ASSERT(pip_to_net[pip] != nullptr);
wire_fanout[getPipSrcWire(pip)]--;
WireId dst;
dst.index = locInfo(pip)->pip_data[pip.index].dst_idx;
@ -819,8 +823,14 @@ struct Arch : BaseCtx
{
DelayInfo delay;
NPNR_ASSERT(pip != PipId());
delay.min_delay = speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].min_base_delay;
delay.max_delay = speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].max_base_delay;
int fanout = 0;
auto fnd_fanout = wire_fanout.find(getPipSrcWire(pip));
if (fnd_fanout != wire_fanout.end())
fanout = fnd_fanout->second;
delay.min_delay = speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].min_base_delay
+ fanout * speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].min_fanout_adder;
delay.max_delay = speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].max_base_delay
+ fanout * speed_grade->pip_classes[locInfo(pip)->pip_data[pip.index].timing_class].max_fanout_adder;
return delay;
}