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nexus: Add DSP pre-adder support

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Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2020-11-17 16:03:52 +00:00
parent fcde8e2d56
commit 91d746cfc8
2 changed files with 23 additions and 2 deletions
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6
nexus/constids.inc
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@ -322,3 +322,9 @@ X(SFTEN)
X(MULT18X36)
X(MULT36X36H)
X(MULT36X36)
X(SIGNEDC)
X(REGINPUTC)
X(MULTPREADD9X9)
X(MULTPREADD18X18)

19
nexus/pack.cc
View File

@ -1412,8 +1412,6 @@ struct NexusPacker
cell->params[id_GSR] = std::string("DISABLED");
cell->params[id_OPC] = std::string("INPUT_B_AS_PREADDER_OPERAND");
cell->params[id_PREADDCAS_EN] = std::string("DISABLED");
cell->params[id_PREADDCAS_EN] = std::string("DISABLED");
cell->params[id_PREADDCAS_EN] = std::string("DISABLED");
cell->params[id_REGBYPSBL] = std::string("REGISTER");
cell->params[id_REGBYPSBR0] = std::string("BYPASS");
cell->params[id_REGBYPSBR1] = std::string("BYPASS");
@ -1494,6 +1492,8 @@ struct NexusPacker
{id_MULT18X18, {18, 18, 0, 36, 2, 1, 0, false, false}},
{id_MULT18X36, {18, 36, 0, 54, 4, 2, 1, false, false}},
{id_MULT36X36, {36, 36, 0, 72, 8, 4, 2, false, false}},
{id_MULTPREADD9X9, {9, 9, 9, 18, 1, 0, 0, true, false}},
{id_MULTPREADD18X18, {18, 18, 18, 36, 2, 1, 0, true, false}},
};
void pack_dsps()
@ -1542,6 +1542,21 @@ struct NexusPacker
copy_param(ci, id_REGINPUTA, mult9[i], id_REGBYPSA1);
copy_param(ci, id_REGINPUTB, preadd9[i], id_REGBYPSBR0);
// Connect and configure pre-adder if it isn't bypassed
if (mt.has_preadd) {
copy_bus(ctx, ci, id_C, 9 * i, true, preadd9[i], id_C, 0, false, 9);
if (i == (mt.N9x9 - 1))
copy_port(ctx, ci, id_SIGNEDC, preadd9[i], id_C9);
copy_param(ci, id_REGINPUTC, preadd9[i], id_REGBYPSBL);
copy_port(ctx, ci, id_CEC, preadd9[i], id_CECL);
copy_port(ctx, ci, id_RSTC, preadd9[i], id_RSTCL);
// Enable preadder
preadd9[i]->params[id_BYPASS_PREADD9] = std::string("USED");
preadd9[i]->params[id_OPC] = std::string("INPUT_C_AS_PREADDER_OPERAND");
if (i > 0)
preadd9[i]->params[id_PREADDCAS_EN] = std::string("ENABLED");
}
// Connect up signedness for the most significant nonet
if ((b_start + 9) == mt.b_width)
copy_port(ctx, ci, id_SIGNEDB, preadd9[i], id_BSIGNED);