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Place DFF chains

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This commit is contained in:
Miodrag Milanovic 2024-08-07 18:34:57 +02:00
parent 7229fb73f5
commit dddf12a42b
6 changed files with 91 additions and 3 deletions
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1
himbaechel/uarch/ng-ultra/extra_data.h
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@ -206,6 +206,7 @@ enum ClusterPlacement
PLACE_FIFO_WEQ2,
PLACE_FIFO_REQ2,
PLACE_LUT_CHAIN,
PLACE_DFF_CHAIN,
};
enum PipExtra

20
himbaechel/uarch/ng-ultra/location_map.cc
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@ -471,7 +471,7 @@ Loc getNextLocInCYChain(Loc loc)
return result;
}
Loc getNextLocInLutChain(Loc loc)
Loc getNextLocInLUTChain(Loc loc)
{
Loc result = loc;
result.x = loc.x;
@ -480,6 +480,24 @@ Loc getNextLocInLutChain(Loc loc)
return result;
}
Loc getNextLocInDFFChain(Loc loc)
{
Loc result = loc;
if (loc.z == 31) {
if ((loc.x & 3) == 3) {
result.z = -1; // End of chain
return result;
}
result.z = 0;
result.x++;
return result;
}
int z = loc.z + 8;
if (z>31) z++;
result.z = z % 32; // BEL_LUT_Z is 0
return result;
}
Loc getCYFE(Loc root, int pos)
{
int p[] = { 2-1, 25-1, 10-1, 17-1 };

3
himbaechel/uarch/ng-ultra/location_map.h
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@ -29,7 +29,8 @@ namespace ng_ultra {
Loc getNextLocInDSPChain(const NgUltraImpl *impl, Loc loc);
Loc getNextLocInCYChain(Loc loc);
Loc getNextLocInLutChain(Loc loc);
Loc getNextLocInLUTChain(Loc loc);
Loc getNextLocInDFFChain(Loc loc);
Loc getCYFE(Loc root, int pos);
Loc getXLUTFE(Loc root, int pos);
Loc getXRFFE(Loc root, int pos);

3
himbaechel/uarch/ng-ultra/ng_ultra.cc
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@ -644,7 +644,8 @@ bool NgUltraImpl::getChildPlacement(const BaseClusterInfo *cluster, Loc root_loc
Loc child_loc = if_using_basecluster<Loc>(child, [&](const BaseClusterInfo *child) {
switch(child->constr_z) {
case PLACE_CY_CHAIN : { Loc l = getNextLocInCYChain(prev); prev = l; return l; }
case PLACE_LUT_CHAIN : { Loc l = getNextLocInLutChain(prev); prev = l; return l; }
case PLACE_LUT_CHAIN : { Loc l = getNextLocInLUTChain(prev); prev = l; return l; }
case PLACE_DFF_CHAIN : { Loc l = getNextLocInDFFChain(prev); prev = l; return l; }
case PLACE_CY_FE1 ... PLACE_CY_FE4: return getCYFE(root_loc, child->constr_z - PLACE_CY_FE1 );
case PLACE_XLUT_FE1 ... PLACE_XLUT_FE4: return getXLUTFE(root_loc, child->constr_z - PLACE_XLUT_FE1 );
case PLACE_XRF_I1 ... PLACE_XRF_WEA:

66
himbaechel/uarch/ng-ultra/pack.cc
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@ -382,6 +382,71 @@ void NgUltraPacker::pack_xluts(void)
flush_cells();
}
void NgUltraPacker::pack_multi_dffs(void)
{
log_info("Pack multi DFFs...\n");
std::vector<CellInfo*> dff_chain_start;
for (auto &cell : ctx->cells) {
CellInfo &ci = *cell.second;
if (!ci.type.in(id_NX_DFF))
continue;
NetInfo *inp = ci.getPort(id_I);
if (!inp || (inp->driver.cell && inp->driver.cell->type.in(id_NX_DFF))) continue;
int cnt = 0;
CellInfo *dff = &ci;
while(1) {
NetInfo *o = dff->getPort(id_O);
if (o->users.entries() != 1) break;
dff = (*o->users.begin()).cell;
if (dff->type == id_NX_DFF && (*o->users.begin()).port == id_I) {
cnt++;
} else break;
}
if (cnt)
dff_chain_start.push_back(&ci);
}
int dff_only = 0, lut_and_ff = 0;
for (auto dff : dff_chain_start) {
CellInfo *root = create_cell_ptr(id_BEYOND_FE, ctx->id(dff->name.str(ctx) + "$fe"));
root->cluster = root->name;
NetInfo *net = dff->getPort(id_I);
NetInfo *o = dff->getPort(id_O);
if (net && net->driver.cell->type == id_NX_LUT && net->users.entries()==1) {
CellInfo *lut = net->driver.cell;
if (!lut->params.count(id_lut_table))
log_error("Cell '%s' missing lut_table\n", lut->name.c_str(ctx));
lut_to_fe(lut, root, false, lut->params[id_lut_table]);
packed_cells.insert(lut->name);
dff_to_fe(dff, root, false);
packed_cells.insert(dff->name);
++lut_and_ff;
} else {
dff_to_fe(dff, root, true);
packed_cells.insert(dff->name);
++dff_only;
}
while(1) {
if (o->users.entries() != 1) break;
dff = (*o->users.begin()).cell;
if (!(dff->type == id_NX_DFF && (*o->users.begin()).port == id_I)) break;
o = dff->getPort(id_O);
CellInfo *new_cell = create_cell_ptr(id_BEYOND_FE, ctx->id(dff->name.str(ctx) + "$fe"));
dff_to_fe(dff, new_cell, true);
++dff_only;
root->constr_children.push_back(new_cell);
new_cell->cluster = root->cluster;
new_cell->constr_z = PLACE_DFF_CHAIN;
packed_cells.insert(dff->name);
}
}
if (lut_and_ff)
log_info(" %6d FEs used as LUT and DFF\n", lut_and_ff);
if (dff_only)
log_info(" %6d FEs used as DFF only\n", dff_only);
flush_cells();
}
void NgUltraPacker::pack_lut_multi_dffs(void)
{
log_info("Pack LUT-multi DFFs...\n");
@ -1994,6 +2059,7 @@ void NgUltraImpl::pack()
packer.pack_cys();
packer.pack_xluts();
packer.pack_lut_multi_dffs();
packer.pack_multi_dffs();
packer.pack_lut_dffs();
packer.pack_dffs();

1
himbaechel/uarch/ng-ultra/pack.h
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@ -48,6 +48,7 @@ struct NgUltraPacker
void update_dffs();
void pack_xluts();
void pack_lut_multi_dffs();
void pack_multi_dffs();
void pack_lut_dffs();
void pack_dffs();
void pack_cys();