riscv
/
yosys
mirror of https://github.com/YosysHQ/yosys.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge pull request #1167 from YosysHQ/eddie/xc7srl_cleanup 

Cleanup synth_xilinx SRL inference, make more consistent
This commit is contained in:
Clifford Wolf 2019-07-09 16:49:08 +02:00 committed by GitHub
parent 7f8c420cf7 810f8c5dbd
commit a429aedc0f
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 25 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
techlibs/xilinx/cells_map.v
View File

@ -56,7 +56,6 @@ module \$__XILINX_SHREG_ (input C, input D, input [31:0] L, input E, output Q, o
localparam [DEPTH-1:0] INIT_R = brev(INIT);
parameter _TECHMAP_CONSTMSK_L_ = 0;
parameter _TECHMAP_CONSTVAL_L_ = 0;
wire CE;
generate
@ -129,26 +128,33 @@ module \$__XILINX_SHREG_ (input C, input D, input [31:0] L, input E, output Q, o
MUXF8 fpga_mux_2 (.O(Q), .I0(T7), .I1(T8), .S(L[6]));
end
end
else if (DEPTH <= 129 && ~&_TECHMAP_CONSTMSK_L_) begin
// Handle cases where fixed-length depth is
// just 1 over a convenient value
\$__XILINX_SHREG_ #(.DEPTH(DEPTH+1), .INIT({INIT,1'b0}), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) _TECHMAP_REPLACE_ (.C(C), .D(D), .L(L), .E(E), .Q(Q));
// For fixed length, if just 1 over a convenient value, decompose
else if (DEPTH <= 129 && &_TECHMAP_CONSTMSK_L_) begin
wire T;
\$__XILINX_SHREG_ #(.DEPTH(DEPTH-1), .INIT(INIT[DEPTH-1:1]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl (.C(C), .D(D), .L({32{1'b1}}), .E(E), .Q(T));
\$__XILINX_SHREG_ #(.DEPTH(1), .INIT(INIT[0]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_last (.C(C), .D(T), .L(L), .E(E), .Q(Q));
end
// For variable length, if just 1 over a convenient value, then bump up one more
else if (DEPTH < 129 && ~&_TECHMAP_CONSTMSK_L_)
\$__XILINX_SHREG_ #(.DEPTH(DEPTH+1), .INIT({INIT,1'b0}), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) _TECHMAP_REPLACE_ (.C(C), .D(D), .L(L), .E(E), .Q(Q));
else begin
localparam lower_clog2 = $clog2((DEPTH+1)/2);
localparam lower_depth = 2 ** lower_clog2;
wire T0, T1, T2, T3;
if (&_TECHMAP_CONSTMSK_L_) begin
\$__XILINX_SHREG_ #(.DEPTH(lower_depth), .INIT(INIT[DEPTH-1:DEPTH-lower_depth]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_0 (.C(C), .D(D), .L(lower_depth-1), .E(E), .Q(T0));
\$__XILINX_SHREG_ #(.DEPTH(DEPTH-lower_depth), .INIT(INIT[DEPTH-lower_depth-1:0]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_1 (.C(C), .D(T0), .L(DEPTH-lower_depth-1), .E(E), .Q(Q), .SO(T3));
end
else begin
\$__XILINX_SHREG_ #(.DEPTH(lower_depth), .INIT(INIT[DEPTH-1:DEPTH-lower_depth]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_0 (.C(C), .D(D), .L(L[lower_clog2-1:0]), .E(E), .Q(T0), .SO(T1));
\$__XILINX_SHREG_ #(.DEPTH(DEPTH-lower_depth), .INIT(INIT[DEPTH-lower_depth-1:0]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_1 (.C(C), .D(T1), .L(L[lower_clog2-1:0]), .E(E), .Q(T2), .SO(T3));
assign Q = L[lower_clog2] ? T2 : T0;
end
if (DEPTH == 2 * lower_depth)
assign SO = T3;
localparam depth0 = 128;
localparam num_srl128 = DEPTH / depth0;
localparam depthN = DEPTH % depth0;
wire [num_srl128 + (depthN > 0 ? 1 : 0) - 1:0] T;
wire [num_srl128 + (depthN > 0 ? 1 : 0) :0] S;
assign S[0] = D;
genvar i;
for (i = 0; i < num_srl128; i++)
\$__XILINX_SHREG_ #(.DEPTH(depth0), .INIT(INIT[DEPTH-1-i*depth0-:depth0]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl (.C(C), .D(S[i]), .L(L[$clog2(depth0)-1:0]), .E(E), .Q(T[i]), .SO(S[i+1]));
if (depthN > 0)
\$__XILINX_SHREG_ #(.DEPTH(depthN), .INIT(INIT[depthN-1:0]), .CLKPOL(CLKPOL), .ENPOL(ENPOL)) fpga_srl_last (.C(C), .D(S[num_srl128]), .L(L[$clog2(depth0)-1:0]), .E(E), .Q(T[num_srl128]));
if (&_TECHMAP_CONSTMSK_L_)
assign Q = T[num_srl128 + (depthN > 0 ? 1 : 0) - 1];
else
assign Q = T[L[DEPTH-1:$clog2(depth0)]];
end
endgenerate
endmodule