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ecp5: Fix packing of FFs into carry/DRAM slices

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Signed-off-by: David Shah <davey1576@gmail.com>
This commit is contained in:
David Shah 2018-10-01 18:19:56 +01:00
parent 2c96d4770d
commit fd4498736e
1 changed files with 12 additions and 4 deletions
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16
ecp5/pack.cc
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@ -496,6 +496,7 @@ class Ecp5Packer
std::vector<std::vector<CellInfo *>> packed_chains;
// Chain packing
std::vector<std::tuple<CellInfo *, CellInfo *, int>> ff_packing;
for (auto &chain : all_chains) {
int cell_count = 0;
std::vector<CellInfo *> tile_ffs;
@ -513,7 +514,7 @@ class Ecp5Packer
if (f0net != nullptr) {
ff0 = net_only_drives(ctx, f0net, is_ff, ctx->id("DI"), false);
if (ff0 != nullptr && can_add_ff_to_tile(tile_ffs, ff0)) {
ff_to_slice(ctx, ff0, slice.get(), 0, true);
ff_packing.push_back(std::make_tuple(ff0, slice.get(), 0));
tile_ffs.push_back(ff0);
packed_cells.insert(ff0->name);
}
@ -525,7 +526,7 @@ class Ecp5Packer
ff1 = net_only_drives(ctx, f1net, is_ff, ctx->id("DI"), false);
if (ff1 != nullptr && (ff0 == nullptr || can_pack_ffs(ff0, ff1)) &&
can_add_ff_to_tile(tile_ffs, ff1)) {
ff_to_slice(ctx, ff1, slice.get(), 1, true);
ff_packing.push_back(std::make_tuple(ff1, slice.get(), 1));
tile_ffs.push_back(ff1);
packed_cells.insert(ff1->name);
}
@ -538,6 +539,9 @@ class Ecp5Packer
packed_chains.push_back(packed_chain);
}
for (auto ff : ff_packing)
ff_to_slice(ctx, std::get<0>(ff), std::get<1>(ff), std::get<2>(ff), true);
// Relative chain placement
for (auto &chain : packed_chains) {
chain.at(0)->constr_abs_z = true;
@ -586,6 +590,7 @@ class Ecp5Packer
disconnect_port(ctx, ci, ctx->id("RAD[3]"));
// Attempt to pack FFs into RAM slices
std::vector<std::tuple<CellInfo *, CellInfo *, int>> ff_packing;
std::vector<CellInfo *> tile_ffs;
for (auto slice : {ram0_slice.get(), ram1_slice.get()}) {
CellInfo *ff0 = nullptr;
@ -593,7 +598,7 @@ class Ecp5Packer
if (f0net != nullptr) {
ff0 = net_only_drives(ctx, f0net, is_ff, ctx->id("DI"), false);
if (ff0 != nullptr && can_add_ff_to_tile(tile_ffs, ff0)) {
ff_to_slice(ctx, ff0, slice, 0, true);
ff_packing.push_back(std::make_tuple(ff0, slice, 0));
tile_ffs.push_back(ff0);
packed_cells.insert(ff0->name);
}
@ -605,13 +610,16 @@ class Ecp5Packer
ff1 = net_only_drives(ctx, f1net, is_ff, ctx->id("DI"), false);
if (ff1 != nullptr && (ff0 == nullptr || can_pack_ffs(ff0, ff1)) &&
can_add_ff_to_tile(tile_ffs, ff1)) {
ff_to_slice(ctx, ff1, slice, 1, true);
ff_packing.push_back(std::make_tuple(ff1, slice, 1));
tile_ffs.push_back(ff1);
packed_cells.insert(ff1->name);
}
}
}
for (auto ff : ff_packing)
ff_to_slice(ctx, std::get<0>(ff), std::get<1>(ff), std::get<2>(ff), true);
// Setup placement constraints
ram0_slice->constr_abs_z = true;
ram0_slice->constr_z = 0;