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mistral: improve ALM packing in LABs

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This commit is contained in:
Lofty 2023-06-05 02:49:53 +01:00
parent f47ec47143
commit ff094becab
1 changed files with 42 additions and 3 deletions
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45
mistral/lab.cc
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@ -534,6 +534,15 @@ void Arch::update_alm_input_count(uint32_t lab, uint8_t alm)
alm_data.unique_input_count = total_inputs;
}
const std::array<int, 6> tdmux_set = {
0, // A
1, // B
0, // C
1, // D
2, // E
3, // F
};
bool Arch::check_lab_input_count(uint32_t lab) const
{
// There are only 46 TD signals available to route signals from general routing to the ALM input. Currently, we
@ -544,10 +553,40 @@ bool Arch::check_lab_input_count(uint32_t lab) const
// currently perfunctory place and route algorithms to achieve satisfactory runtimes.
int count = 0;
auto &lab_data = labs.at(lab);
for (int i = 0; i < 10; i++) {
count += lab_data.alms.at(i).unique_input_count;
pool<std::pair<IdString, int>> unique_inputs;
for (int alm = 0; alm < 10; alm++) {
// TODO: duplication with above
auto &alm_data = labs.at(lab).alms.at(alm);
// Get cells into an array for fast access
std::array<const CellInfo *, 2> luts{getBoundBelCell(alm_data.lut_bels[0]), getBoundBelCell(alm_data.lut_bels[1])};
std::array<const CellInfo *, 4> ffs{getBoundBelCell(alm_data.ff_bels[0]), getBoundBelCell(alm_data.ff_bels[1]),
getBoundBelCell(alm_data.ff_bels[2]), getBoundBelCell(alm_data.ff_bels[3])};
for (int i = 0; i < 2; i++) {
if (!luts[i])
continue;
for (int j = 0; j < luts[i]->combInfo.lut_input_count; j++)
if (luts[i]->combInfo.lut_in[j])
unique_inputs.insert(std::make_pair(luts[i]->combInfo.lut_in[j]->name, tdmux_set.at(j)));
}
for (int i = 0; i < 4; i++) {
const CellInfo *ff = ffs[i];
if (!ff)
continue;
if (ff->ffInfo.sdata) {
unique_inputs.insert(std::make_pair(ff->ffInfo.sdata->name, tdmux_set.at(4)));
unique_inputs.insert(std::make_pair(ff->ffInfo.sdata->name, tdmux_set.at(5)));
}
// FF input doesn't consume routing resources if driven by associated LUT
if (ff->ffInfo.datain && (!luts[i / 2] || ff->ffInfo.datain != luts[i / 2]->combInfo.comb_out)) {
unique_inputs.insert(std::make_pair(ff->ffInfo.datain->name, tdmux_set.at(4)));
unique_inputs.insert(std::make_pair(ff->ffInfo.datain->name, tdmux_set.at(5)));
}
}
}
return (count <= 42);
return (unique_inputs.size() <= 42);
}
bool Arch::check_mlab_groups(uint32_t lab) const