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

fabulous: Global constant wires scheme

Browse Source 
Signed-off-by: gatecat <gatecat@ds0.me>
This commit is contained in:
gatecat 2023-02-22 14:51:51 +01:00 committed by myrtle
parent 1809e18c7b
commit 14050f991b
6 changed files with 140 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
generic/viaduct/fabulous/constids.inc
View File

@ -99,3 +99,13 @@ X(M_EF)
X(M_AH)
X(I0MUX)
X(GND0)
X(GND)
X(VCC0)
X(VCC)
X(VDD0)
X(VDD)
X(_CONST0_DRV)
X(_CONST1_DRV)

94
generic/viaduct/fabulous/fabulous.cc
View File

@ -69,6 +69,7 @@ struct FabulousImpl : ViaductAPI
blk_trk = std::make_unique<BlockTracker>(ctx, cfg);
is_new_fab ? init_bels_v2() : init_bels_v1();
init_pips();
init_pseudo_constant_wires();
ctx->setDelayScaling(3.0, 3.0);
ctx->delay_epsilon = 0.25;
ctx->ripup_penalty = 0.5;
@ -105,7 +106,7 @@ struct FabulousImpl : ViaductAPI
void postRoute() override
{
if (!fasm_file.empty())
fabulous_write_fasm(ctx, cfg, fasm_file);
fabulous_write_fasm(ctx, cfg, pp_tags, fasm_file);
}
void prePlace() override
@ -150,11 +151,18 @@ struct FabulousImpl : ViaductAPI
pool<IdString> warned_beltypes;
void add_pseudo_pip(WireId src, WireId dst, IdString pip_type)
std::vector<PseudoPipTags> pp_tags;
void add_pseudo_pip(WireId src, WireId dst, IdString pip_type, float delay = 1.0,
PseudoPipTags tags = PseudoPipTags())
{
const auto &src_data = ctx->wire_info(src);
IdStringList pip_name = IdStringList::concat(ctx->getWireName(src), ctx->getWireName(dst));
ctx->addPip(pip_name, pip_type, src, dst, ctx->getDelayFromNS(1.0), Loc(src_data.x, src_data.y, 0));
PipId idx =
ctx->addPip(pip_name, pip_type, src, dst, ctx->getDelayFromNS(delay), Loc(src_data.x, src_data.y, 0));
if (idx.index >= int(pp_tags.size()))
pp_tags.resize(idx.index + 1);
pp_tags.at(idx.index) = tags;
}
void handle_bel_ports(BelId bel, IdString tile, IdString bel_type, const std::vector<parser_view> &ports)
@ -405,6 +413,7 @@ struct FabulousImpl : ViaductAPI
}
}
int max_x = 0, max_y = 0;
void init_pips()
{
std::ifstream in = open_data_rel(is_new_fab ? "/.FABulous/pips.txt" : "/npnroutput/pips.txt");
@ -418,8 +427,11 @@ struct FabulousImpl : ViaductAPI
IdString pip_name = csv.next_field().to_id(ctx);
WireId src_wire = get_wire(src_tile, src_port, src_port);
WireId dst_wire = get_wire(dst_tile, dst_port, dst_port);
Loc loc = tile_loc(src_tile);
max_x = std::max(loc.x, max_x);
max_y = std::max(loc.y, max_y);
ctx->addPip(IdStringList::concat(src_tile, pip_name), pip_name, src_wire, dst_wire,
ctx->getDelayFromNS(0.05 * delay), tile_loc(src_tile));
ctx->getDelayFromNS(0.05 * delay), loc);
}
}
@ -455,6 +467,67 @@ struct FabulousImpl : ViaductAPI
return ctx->addWire(wire_name, type, loc.x, loc.y);
}
void init_pseudo_constant_wires()
{
for (int y = 0; y <= max_y; y++) {
for (int x = 0; x <= max_x; x++) {
for (int c = 0; c <= 1; c++) {
IdString name = ctx->idf("$CONST%d", c);
IdString tile = ctx->idf("X%dY%d", x, y);
WireId const_wire = get_wire(tile, name, name);
// Driver bel; always at 0;0
if (x == 0 && y == 0) {
int z = 0;
while (ctx->bel_by_loc.count(Loc(x, y, z)))
z++;
BelId const_driver = ctx->addBel(IdStringList::concat(tile, ctx->idf("_CONST%d_DRV", c)),
ctx->idf("_CONST%d_DRV", c), Loc(x, y, z), true, true);
ctx->addBelInput(const_driver, id_O, const_wire);
}
if (x > 0) {
// 'right' pip
WireId prev_wire = get_wire(ctx->idf("X%dY%d", 0, y), name, name);
add_pseudo_pip(prev_wire, const_wire, name, 0.1);
}
if (y > 0) {
// 'down' pip
WireId prev_wire = get_wire(ctx->idf("X%dY%d", x, 0), name, name);
add_pseudo_pip(prev_wire, const_wire, name, 0.1);
}
}
}
}
// LUTs can act as constant drivers if they aren't used.
// To avoid an exorbitant number of pips, only do this for the first LUT in a tile
// This pip will only be enabled if the LUT isn't used
for (BelId bel : ctx->getBels()) {
if (!ctx->getBelType(bel).in(id_FABULOUS_LC, id_FABULOUS_COMB))
continue;
Loc loc = ctx->getBelLocation(bel);
WireId o = ctx->getBelPinWire(bel, id_O);
for (int c = 0; c <= 1; c++) {
IdString const_name = ctx->idf("$CONST%d", c);
WireId const_wire = get_wire(ctx->idf("X%dY%d", loc.x, loc.y), const_name, const_name);
add_pseudo_pip(const_wire, o, const_name, 0.1, PseudoPipTags(PseudoPipTags::LUT_CONST, bel, c));
}
}
// We can also have dedicated constant wires in the fabric
for (WireId wire : ctx->getWires()) {
auto &wire_data = ctx->wire_info(wire);
IdString name_suffix = wire_data.name[1];
int const_val = -1;
if (name_suffix.in(id_GND, id_GND0))
const_val = 0;
else if (name_suffix.in(id_VCC, id_VCC0, id_VDD, id_VDD0))
const_val = 1;
else
continue;
IdString const_name = ctx->idf("$CONST%d", const_val);
WireId const_wire = get_wire(ctx->idf("X%dY%d", wire_data.x, wire_data.y), const_name, const_name);
add_pseudo_pip(const_wire, wire, const_name, 0.1);
}
}
CellTagger cell_tags;
void assign_cell_info()
{
@ -467,6 +540,19 @@ struct FabulousImpl : ViaductAPI
CellInfo *old = ctx->getBoundBelCell(bel);
blk_trk->update_bel(bel, old, cell);
}
bool checkPipAvail(PipId pip) const override
{
if (pip.index >= int(pp_tags.size()))
return true;
const auto &tags = pp_tags.at(pip.index);
if (tags.type == PseudoPipTags::LUT_CONST) {
return ctx->checkBelAvail(tags.bel);
} else {
// TODO: LUT permuation pseudopips
return true;
}
}
};
struct FabulousArch : ViaductArch

25
generic/viaduct/fabulous/fasm.cc
View File

@ -34,8 +34,9 @@ NEXTPNR_NAMESPACE_BEGIN
namespace {
struct FabFasmWriter
{
FabFasmWriter(const Context *ctx, const FabricConfig &cfg, const std::string &filename)
: ctx(ctx), cfg(cfg), out(filename)
FabFasmWriter(const Context *ctx, const FabricConfig &cfg, const std::vector<PseudoPipTags> &pip_tags,
const std::string &filename)
: ctx(ctx), cfg(cfg), pip_tags(pip_tags), out(filename)
{
if (!out)
log_error("failed to open fasm file '%s' for writing\n", filename.c_str());
@ -53,7 +54,19 @@ struct FabFasmWriter
void write_pip(PipId pip)
{
auto &data = ctx->pip_info(pip);
if (data.type.in(id_global_clock, id_O2Q))
if (pip.index < int(pip_tags.size()) && pip_tags.at(pip.index).type != PseudoPipTags::NONE) {
// pseudo PIP
const auto &tag = pip_tags.at(pip.index);
if (tag.type == PseudoPipTags::LUT_CONST) {
NPNR_ASSERT(ctx->checkBelAvail(tag.bel));
prefix = format_name(ctx->getBelName(tag.bel)) + ".";
write_int_vector(stringf("INIT[%d:0]", (1U << cfg.clb.lut_k) - 1), 0, 1U << cfg.clb.lut_k,
(tag.data & 0x1));
prefix = "";
}
return;
}
if (data.type.in(id_global_clock, id_O2Q) || data.type.c_str(ctx)[0] == '$')
return; // pseudo-pips with no underlying bitstream bits
// write pip name but with '.' instead of '/' for separator
out << format_name(data.name) << std::endl;
@ -194,13 +207,15 @@ struct FabFasmWriter
const Context *ctx;
const FabricConfig &cfg;
const std::vector<PseudoPipTags> &pip_tags;
std::ofstream out;
};
} // namespace
void fabulous_write_fasm(const Context *ctx, const FabricConfig &cfg, const std::string &filename)
void fabulous_write_fasm(const Context *ctx, const FabricConfig &cfg, const std::vector<PseudoPipTags> &pip_tags,
const std::string &filename)
{
FabFasmWriter wr(ctx, cfg, filename);
FabFasmWriter wr(ctx, cfg, pip_tags, filename);
wr.write_fasm();
}

4
generic/viaduct/fabulous/fasm.h
View File

@ -22,10 +22,12 @@
#include "fab_cfg.h"
#include "nextpnr.h"
#include "validity_check.h"
NEXTPNR_NAMESPACE_BEGIN
void fabulous_write_fasm(const Context *ctx, const FabricConfig &cfg, const std::string &filename);
void fabulous_write_fasm(const Context *ctx, const FabricConfig &cfg, const std::vector<PseudoPipTags> &pip_tags,
const std::string &filename);
NEXTPNR_NAMESPACE_END

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

@ -194,7 +194,8 @@ struct FabulousPacker
}
}
bool check_cluster_legality(CellInfo *lc) {
bool check_cluster_legality(CellInfo *lc)
{
if (lc->cluster == ClusterId())
return true;
CLBState test_clb(cfg.clb);
@ -204,7 +205,7 @@ struct FabulousPacker
if (ci->type == id_FABULOUS_LC) {
NPNR_ASSERT(ci->constr_z >= 0 && ci->constr_z < int(cfg.clb.lc_per_clb));
test_clb.lc_comb[ci->constr_z] = ci;
} else if (ci->type.in(id_FABULOUS_MUX2, id_FABULOUS_MUX4, id_FABULOUS_MUX8)) {
} else if (ci->type.in(id_FABULOUS_MUX2, id_FABULOUS_MUX4, id_FABULOUS_MUX8)) {
int mux_z = (ci->constr_z - cfg.clb.lc_per_clb - 1);
NPNR_ASSERT(mux_z >= 0 && mux_z < int(cfg.clb.lc_per_clb));
test_clb.mux[mux_z] = ci;
@ -317,9 +318,7 @@ struct FabulousPacker
void handle_constants()
{
const dict<IdString, Property> vcc_params = {{id_INIT, Property(0x3, 2)}};
const dict<IdString, Property> gnd_params = {{id_INIT, Property(0x0, 2)}};
h.replace_constants(CellTypePort(id_LUT1, id_O), CellTypePort(id_LUT1, id_O), vcc_params, gnd_params);
h.replace_constants(CellTypePort(id__CONST1_DRV, id_O), CellTypePort(id__CONST0_DRV, id_O), {}, {});
}
void handle_io()

13
generic/viaduct/fabulous/validity_check.h
View File

@ -122,6 +122,19 @@ struct BlockTracker
bool check_validity(BelId bel, const FabricConfig &cfg, const CellTagger &cell_data);
};
struct PseudoPipTags
{
BelId bel;
enum PPType : uint16_t
{
NONE,
LUT_CONST,
LUT_PERM,
} type;
uint16_t data;
PseudoPipTags(PPType type = NONE, BelId bel = BelId(), uint16_t data = 0x0) : bel(bel), type(type), data(data) {}
};
NEXTPNR_NAMESPACE_END
#endif