caiyu/nextpnr
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fabulous: Pack, validity check and FASM support for muxes

Browse Source 
Signed-off-by: gatecat <gatecat@ds0.me>
This commit is contained in:
gatecat 2022-09-30 13:27:51 +02:00
parent 124c0fc812
commit 3826a31ad3
4 changed files with 84 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
generic/viaduct/fabulous/fabulous.cc
View File

@ -317,12 +317,13 @@ struct FabulousImpl : ViaductAPI
}
// K select inputs
for (unsigned j = 0; j < k; j++) {
ctx->addBelInput(mux, ctx->idf("S%d", j), data.pins.at(ctx->idf("S%d",
(m == 8 && j == 2) ? 3 : ((i / m) * k + j)
)).wire);
ctx->addBelInput(mux, ctx->idf("S%d", j),
data.pins.at(ctx->idf("S%d", (m == 8 && j == 2) ? 3 : ((i / m) * k + j))).wire);
}
// Output
IdString output = (m == 2) ? mux_outs.at(i / m) : (m == 4) ? mux_outs.at((i / m) * k + 1) : mux_outs.at(3);
IdString output = (m == 2) ? mux_outs.at(i / m)
: (m == 4) ? mux_outs.at((i / m) * k + 1)
: mux_outs.at(3);
ctx->addBelOutput(mux, id_O, data.pins.at(output).wire);
}
}

11
generic/viaduct/fabulous/fasm.cc
View File

@ -123,6 +123,14 @@ struct FabFasmWriter
write_bool(lc, "NEG_SR");
write_bool(lc, "ASYNC_SR");
}
if (lc->type.in(id_FABULOUS_MUX4, id_FABULOUS_MUX8)) {
// TODO: don't hardcode prefix
out << prefix << "I.c0" << std::endl;
}
if (lc->type == id_FABULOUS_MUX8) {
// TODO: don't hardcode prefix
out << prefix << "I.c1" << std::endl;
}
}
void write_io(const CellInfo *io)
@ -161,7 +169,8 @@ struct FabFasmWriter
void write_cell(const CellInfo *ci)
{
out << stringf("# config for cell '%s'\n", ctx->nameOf(ci)) << std::endl;
if (ci->type.in(id_FABULOUS_COMB, id_FABULOUS_FF, id_FABULOUS_LC))
if (ci->type.in(id_FABULOUS_COMB, id_FABULOUS_FF, id_FABULOUS_LC, id_FABULOUS_MUX2, id_FABULOUS_MUX4,
id_FABULOUS_MUX8))
write_logic(ci);
else if (ci->type == id_IO_1_bidirectional_frame_config_pass)
write_io(ci);

48
generic/viaduct/fabulous/pack.cc
View File

@ -132,6 +132,53 @@ struct FabulousPacker
}
}
void pack_muxes()
{
// TODO: don't hardcode z-offset -- we should come up with our own constraint structure
int lut_muxes_dz = 9;
int lut_lut_dz = 1;
for (auto &cell : ctx->cells) {
CellInfo *ci = cell.second.get();
unsigned k = 0;
if (ci->type == id_FABULOUS_MUX2)
k = 1;
else if (ci->type == id_FABULOUS_MUX4)
k = 2;
else if (ci->type == id_FABULOUS_MUX8)
k = 3;
else
continue;
unsigned m = (1U << k);
std::vector<CellInfo *> luts;
for (unsigned i = 0; i < m; i++) {
NetInfo *ii = ci->getPort(ctx->idf("I%d", i));
if (!ii || !ii->driver.cell || !ii->driver.cell->type.in(id_FABULOUS_LC, id_FABULOUS_COMB) ||
ii->driver.port != id_O)
log_error("mux %s input I%d net %s is not driven by a LUT!\n", ctx->nameOf(ci), i, ctx->nameOf(ii));
CellInfo *lut = ii->driver.cell;
NPNR_ASSERT(lut->cluster == ClusterId());
luts.push_back(lut);
}
luts.at(0)->cluster = luts.at(0)->name;
for (unsigned i = 0; i < m; i++) {
luts.at(i)->cluster = luts.at(0)->name;
luts.at(i)->constr_x = 0;
luts.at(i)->constr_y = 0;
luts.at(i)->constr_z = i * lut_lut_dz;
luts.at(i)->constr_abs_z = false;
if (i > 0)
luts.at(0)->constr_children.push_back(luts.at(i));
}
int extra_mux_dz = (m == 8) ? 7 : (m == 4) ? 1 : 0;
ci->cluster = luts.at(0)->name;
ci->constr_x = 0;
ci->constr_y = 0;
ci->constr_z = lut_muxes_dz + extra_mux_dz;
ci->constr_abs_z = false;
luts.at(0)->constr_children.push_back(ci);
}
}
void pack_ffs()
{
pool<IdString> to_delete;
@ -238,6 +285,7 @@ struct FabulousPacker
handle_constants();
handle_io();
pack_luts();
pack_muxes();
prepare_ffs();
pack_ffs();
}

21
generic/viaduct/fabulous/validity_check.cc
View File

@ -33,6 +33,7 @@ CLBState::CLBState(const LogicConfig &cfg)
if (cfg.split_lc) {
ff = std::make_unique<CellInfo *[]>(cfg.lc_per_clb * cfg.ff_per_lc);
}
mux = std::make_unique<CellInfo *[]>(cfg.lc_per_clb);
// TODO: mux
}
@ -173,6 +174,26 @@ bool CLBState::check_validity(const LogicConfig &cfg, const CellTagger &cell_dat
}
}
}
// don't allow mixed MUX types in the classic fabulous arch where ctrl sigs are shared
int tile_mux_type = 0;
for (unsigned z = 0; z < cfg.lc_per_clb; z++) {
const CellInfo *m = mux[z];
if (!m)
continue;
int this_mux = 0;
if (m->type == id_FABULOUS_MUX2)
this_mux = 2;
else if (m->type == id_FABULOUS_MUX4)
this_mux = 4;
else if (m->type == id_FABULOUS_MUX8)
this_mux = 8;
else
NPNR_ASSERT_FALSE("unknown mux type");
if (tile_mux_type == 0)
tile_mux_type = this_mux;
else if (tile_mux_type != this_mux)
return false;
}
// TODO: other checks...
return true;
}