yosys/passes/pmgen/xilinx_dsp.pmg

317 lines
8.7 KiB
Plaintext

pattern xilinx_dsp
state <SigBit> clock
state <SigSpec> sigA sigffAmuxY sigB sigffBmuxY sigC sigM sigP
state <IdString> postAddAB postAddMuxAB
state <bool> ffAenpol ffBenpol ffMenpol ffPenpol
match dsp
select dsp->type.in(\DSP48E1)
endmatch
code sigA sigffAmuxY sigB sigffBmuxY sigM
sigA = port(dsp, \A);
int i;
for (i = GetSize(sigA)-1; i > 0; i--)
if (sigA[i] != sigA[i-1])
break;
// Do not remove non-const sign bit
if (sigA[i].wire)
++i;
sigA.remove(i, GetSize(sigA)-i);
sigB = port(dsp, \B);
for (i = GetSize(sigB)-1; i > 0; i--)
if (sigB[i] != sigB[i-1])
break;
// Do not remove non-const sign bit
if (sigB[i].wire)
++i;
sigB.remove(i, GetSize(sigB)-i);
SigSpec P = port(dsp, \P);
// Only care about those bits that are used
for (i = 0; i < GetSize(P); i++) {
if (nusers(P[i]) <= 1)
break;
sigM.append(P[i]);
}
log_assert(nusers(P.extract_end(i)) <= 1);
//if (GetSize(sigM) <= 10)
// reject;
sigffAmuxY = SigSpec();
sigffBmuxY = SigSpec();
endcode
match ffA
if param(dsp, \AREG).as_int() == 0
select ffA->type.in($dff)
// DSP48E1 does not support clock inversion
select param(ffA, \CLK_POLARITY).as_bool()
filter GetSize(port(ffA, \Q)) >= GetSize(sigA)
slice offset GetSize(port(ffA, \Q))
filter offset+GetSize(sigA) <= GetSize(port(ffA, \Q))
filter port(ffA, \Q).extract(offset, GetSize(sigA)) == sigA
optional
endmatch
code sigA sigffAmuxY clock
if (ffA) {
for (auto b : port(ffA, \Q))
if (b.wire->get_bool_attribute(\keep))
reject;
clock = port(ffA, \CLK).as_bit();
SigSpec A = sigA;
A.replace(port(ffA, \Q), port(ffA, \D));
// Only search for ffAmux if ffA.Q has at
// least 3 users (ffA, dsp, ffAmux) and
// its ffA.D only has two (ffA, ffAmux)
if (nusers(sigA) >= 3 && nusers(A) == 2)
sigffAmuxY = sigA;
sigA = std::move(A);
}
endcode
match ffAmux
if !sigffAmuxY.empty()
select ffAmux->type.in($mux)
filter GetSize(port(ffAmux, \Y)) >= GetSize(sigA)
slice offset GetSize(port(ffAmux, \Y))
filter offset+GetSize(sigA) <= GetSize(port(ffAmux, \Y))
filter port(ffAmux, \Y).extract(offset, GetSize(sigA)) == sigA
choice <IdString> BA {\B, \A}
filter offset+GetSize(sigffAmuxY) <= GetSize(port(ffAmux, \Y))
filter port(ffAmux, BA).extract(offset, GetSize(sigffAmuxY)) == sigffAmuxY
define <bool> pol (BA == \B)
set ffAenpol pol
optional
endmatch
match ffB
if param(dsp, \BREG).as_int() == 0
select ffB->type.in($dff)
// DSP48E1 does not support clock inversion
select param(ffB, \CLK_POLARITY).as_bool()
filter GetSize(port(ffB, \Q)) >= GetSize(sigB)
slice offset GetSize(port(ffB, \Q))
filter offset+GetSize(sigB) <= GetSize(port(ffB, \Q))
filter port(ffB, \Q).extract(offset, GetSize(sigB)) == sigB
optional
endmatch
code sigB sigffBmuxY clock
if (ffB) {
for (auto b : port(ffB, \Q))
if (b.wire->get_bool_attribute(\keep))
reject;
SigBit c = port(ffB, \CLK).as_bit();
if (clock != SigBit() && c != clock)
reject;
clock = c;
SigSpec B = sigB;
B.replace(port(ffB, \Q), port(ffB, \D));
// Only search for ffBmux if ffB.Q has at
// least 3 users (ffB, dsp, ffBmux) and
// its ffB.D only has two (ffB, ffBmux)
if (nusers(sigB) >= 3 && nusers(B) == 2)
sigffBmuxY = sigB;
sigB = std::move(B);
}
endcode
match ffBmux
if !sigffBmuxY.empty()
select ffBmux->type.in($mux)
filter GetSize(port(ffBmux, \Y)) >= GetSize(sigB)
slice offset GetSize(port(ffBmux, \Y))
filter offset+GetSize(sigB) <= GetSize(port(ffBmux, \Y))
filter port(ffBmux, \Y).extract(offset, GetSize(sigB)) == sigB
choice <IdString> BA {\B, \A}
filter offset+GetSize(sigffBmuxY) <= GetSize(port(ffBmux, \Y))
filter port(ffBmux, BA).extract(offset, GetSize(sigffBmuxY)) == sigffBmuxY
define <bool> pol (BA == \B)
set ffBenpol pol
optional
endmatch
match ffMmux
select ffMmux->type.in($mux)
choice <IdString> BA {\B, \A}
// new-value net must have exactly two users: dsp and ffM
select nusers(port(ffMmux, BA)) == 2
define <IdString> AB (BA == \B ? \A : \B)
// keep-last-value net must have at least three users: ffMmux, ffM, downstream sink(s)
select nusers(port(ffMmux, AB)) >= 3
// ffMmux output must have two users: ffMmux and ffM.D
select nusers(port(ffMmux, \Y)) == 2
filter GetSize(port(ffMmux, \Y)) <= GetSize(sigM)
filter port(ffMmux, BA) == sigM.extract(0, GetSize(port(ffMmux, \Y)))
// Remaining bits on sigM must not have any other users
filter nusers(sigM.extract_end(GetSize(port(ffMmux, BA)))) <= 1
define <bool> pol (BA == \B)
set ffMenpol pol
optional
endmatch
code sigM
if (ffMmux)
sigM = port(ffMmux, \Y);
endcode
match ffM
if param(dsp, \MREG).as_int() == 0
select ffM->type.in($dff)
// DSP48E1 does not support clock inversion
select param(ffM, \CLK_POLARITY).as_bool()
select nusers(port(ffM, \D)) == 2
filter GetSize(port(ffM, \D)) <= GetSize(sigM)
filter port(ffM, \D) == sigM.extract(0, GetSize(port(ffM, \D)))
// Remaining bits on sigM must not have any other users
filter nusers(sigM.extract_end(GetSize(port(ffM, \D)))) <= 1
// Check ffMmux (when present) is a $dff enable mux
filter !ffMmux || port(ffM, \Q) == port(ffMmux, ffMenpol ? \A : \B)
optional
endmatch
code clock sigM sigP
if (ffM) {
sigM = port(ffM, \Q);
for (auto b : sigM)
if (b.wire->get_bool_attribute(\keep))
reject;
SigBit c = port(ffM, \CLK).as_bit();
if (clock != SigBit() && c != clock)
reject;
clock = c;
}
// Cannot have ffMmux enable mux without ffM
else if (ffMmux)
reject;
sigP = sigM;
endcode
match postAdd
// Ensure that Z mux is not already used
if port(dsp, \OPMODE).extract(4,3).is_fully_zero()
select postAdd->type.in($add)
select GetSize(port(postAdd, \Y)) <= 48
select nusers(port(postAdd, \Y)) == 2
choice <IdString> AB {\A, \B}
select nusers(port(postAdd, AB)) <= 3
filter ffMmux || nusers(port(postAdd, AB)) == 2
filter !ffMmux || nusers(port(postAdd, AB)) == 3
filter GetSize(port(postAdd, AB)) <= GetSize(sigP)
filter port(postAdd, AB) == sigP.extract(0, GetSize(port(postAdd, AB)))
filter nusers(sigP.extract_end(GetSize(port(postAdd, AB)))) <= 1
set postAddAB AB
optional
endmatch
code sigC sigP
if (postAdd) {
sigC = port(postAdd, postAddAB == \A ? \B : \A);
// TODO for DSP48E1, which will have sign extended inputs/outputs
//int natural_mul_width = GetSize(port(dsp, \A)) + GetSize(port(dsp, \B));
//int actual_mul_width = GetSize(sigP);
//int actual_acc_width = GetSize(sigC);
//if ((actual_acc_width > actual_mul_width) && (natural_mul_width > actual_mul_width))
// reject;
//if ((actual_acc_width != actual_mul_width) && (param(dsp, \A_SIGNED).as_bool() != param(postAdd, \A_SIGNED).as_bool()))
// reject;
sigP = port(postAdd, \Y);
}
endcode
match ffPmux
if param(dsp, \PREG).as_int() == 0
if nusers(sigP) == 2
select ffPmux->type.in($mux)
choice <IdString> BA {\B, \A}
// new-value net must have exactly two users: dsp and ffP
select nusers(port(ffPmux, BA)) == 2
define <IdString> AB (BA == \B ? \A : \B)
// keep-last-value net must have at least three users: ffPmux, ffP, downstream sink(s)
select nusers(port(ffPmux, AB)) >= 3
// ffPmux output must have two users: ffPmux and ffP.D
select nusers(port(ffPmux, \Y)) == 2
filter GetSize(port(ffPmux, \Y)) <= GetSize(sigP)
filter port(ffPmux, BA) == sigP.extract(0, GetSize(port(ffPmux, \Y)))
// Remaining bits on sigP must not have any other users
filter nusers(sigP.extract_end(GetSize(port(ffPmux, BA)))) <= 1
define <bool> pol (BA == \B)
set ffPenpol pol
optional
endmatch
code sigP
if (ffPmux)
sigP.replace(port(ffPmux, ffPenpol ? \A : \B), port(ffPmux, \Y));
endcode
match ffP
if param(dsp, \PREG).as_int() == 0
if nusers(sigP) == 2
select ffP->type.in($dff)
// DSP48E1 does not support clock inversion
select param(ffP, \CLK_POLARITY).as_bool()
filter GetSize(port(ffP, \D)) >= GetSize(sigP)
slice offset GetSize(port(ffP, \D))
filter offset+GetSize(sigP) <= GetSize(port(ffP, \D))
filter port(ffP, \D).extract(offset, GetSize(sigP)) == sigP
// Check ffPmux (when present) is a $dff enable mux
filter !ffPmux || port(ffP, \Q) == port(ffPmux, ffPenpol ? \A : \B)
optional
endmatch
code ffP sigP clock
if (ffP) {
for (auto b : port(ffP, \Q))
if (b.wire->get_bool_attribute(\keep))
reject;
SigBit c = port(ffP, \CLK).as_bit();
if (clock != SigBit() && c != clock)
reject;
clock = c;
sigP.replace(port(ffP, \D), port(ffP, \Q));
}
// Cannot have ffPmux enable mux without ffP
else if (ffPmux)
reject;
endcode
match postAddMux
if postAdd
if ffP
select postAddMux->type.in($mux)
select nusers(port(postAddMux, \Y)) == 2
choice <IdString> AB {\A, \B}
index <SigSpec> port(postAddMux, AB) === sigP
index <SigSpec> port(postAddMux, \Y) === sigC
set postAddMuxAB AB
optional
endmatch
code sigC
if (postAddMux)
sigC = port(postAddMux, postAddMuxAB == \A ? \B : \A);
endcode
code
accept;
endcode