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start modify files to reflect cyclone iv LE - architecture

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This commit is contained in:
Artur Swiderski 2020-10-15 23:31:16 +02:00
parent 8021773072
commit 41f83c19fd
3 changed files with 32 additions and 58 deletions
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25
techlibs/intel_le/common/arith_le_map.v
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@ -30,7 +30,8 @@ wire [Y_WIDTH-1:0] AA = A_buf;
wire [Y_WIDTH-1:0] BB = BI ? ~B_buf : B_buf;
(* force_downto *)
wire [Y_WIDTH-1:0] BX = B_buf;
wire [Y_WIDTH:0] ALM_CARRY;
wire [Y_WIDTH-1:0] BSUM;
wire [Y_WIDTH:0] LE_CARRY;
// Start of carry chain
generate
@ -53,15 +54,23 @@ genvar i;
generate for (i = 0; i < Y_WIDTH; i = i + 1) begin:slice
// TODO: mwk suggests that a pass could merge pre-adder logic into this.
MISTRAL_ALUT_ARITH #(
.LUT0(16'b1010_1010_1010_1010), // Q = A
.LUT1(16'b1100_0011_1100_0011), // Q = C ? B : ~B (LUT1's input to the adder is inverted)
.LUT0(16'b0110_0110_0110_0110) // Q = A ? ~B : B
) alm_i (
.A(AA[i]), .B(BX[i]), .C(BI), .D0(1'b1), .D1(1'b1),
.CI(ALM_CARRY[i]),
.SO(Y[i]),
.CO(ALM_CARRY[i+1])
.A(BI), .B(BX[i]), .C(1'b0), .D(1'b0),
.CI(1'b0),
.SO(BSUM[i]),
.CO()
);
MISTRAL_ALUT_ARITH #(
.LUT0(16'b1010_1010_1010_1010), // SUM = A xor B xor CI
// CARRYi+1 = A and B or A and CI or B and CI
.sum_lutc_input("cin")
) alm_start (
.A(AA[i]), .B(BX[i]), .C(1'b1), .D(1'b1),
.CI(LE_CARRY),
.SO(Y[i]),
.CO(ALM_CARRY[i+1])
);
// ALM carry chain is not directly accessible, so calculate the carry through soft logic if really needed.
assign CO[i] = (AA[i] && BB[i]) || ((Y[i] ^ AA[i] ^ BB[i]) && (AA[i] || BB[i]));
end endgenerate