Fixed bug in systolic multiplier (swapped indices), it only

worked because the testbench set both NUM_SYSTOLIC_CYCLES = 4 and
SYSTOLIC_ARRAY_LENGTH = 4. Now should work with any array power, not
only 2.

1 files changed, 15 insertions, 10 deletions

diff --git a/src/rtl/modexpa7_systolic_multiplier.v b/src/rtl/modexpa7_systolic_multiplier.v
index 513b5aa..8cd28ff 100644
--- a/src/rtl/modexpa7_systolic_multiplier.v
+++ b/src/rtl/modexpa7_systolic_multiplier.v
@@ -652,6 +652,11 @@ module modexpa7_systolic_multiplier #
 	always @(posedge clk)

 		//

 		case (fsm_state)

+			FSM_STATE_LOAD_N_FINAL: begin

+				shreg_load		<= {{SYSTOLIC_NUM_CYCLES-1{1'b0}}, 1'b0};

+				shreg_latency	<= {{SYSTOLIC_PE_LATENCY{1'b0}}, 1'b0};

+				shreg_unload	<= {{SYSTOLIC_NUM_CYCLES-1{1'b0}}, 1'b0};

+			end

 			//

 			FSM_STATE_MULT_A_B_START,

 			FSM_STATE_MULT_AB_N_COEFF_START,

@@ -832,17 +837,17 @@ module modexpa7_systolic_multiplier #
 		

 				if (shreg_now_unloading)

 					for (j=0; j<SYSTOLIC_ARRAY_LENGTH; j=j+1)

-						pe_c_out_mem[syst_cnt_unload][j] <= pe_c_out[j];

+						pe_c_out_mem[j][syst_cnt_unload] <= pe_c_out[j];

 						

 				if (shreg_now_unloading) begin

 				

 					for (j=1; j<SYSTOLIC_ARRAY_LENGTH; j=j+1)

-						pe_t_mem[syst_cnt_unload][j-1] <= pe_p[j];

+						pe_t_mem[j-1][syst_cnt_unload] <= pe_p[j];

 						

 					if (syst_cnt_unload > syst_cnt_zero)

-						pe_t_mem[syst_cnt_unload-1'b1][SYSTOLIC_ARRAY_LENGTH-1] <= pe_p[0];

+						pe_t_mem[SYSTOLIC_ARRAY_LENGTH-1][syst_cnt_unload-1'b1] <= pe_p[0];

 					else

-						pe_t_mem[syst_cnt_last][SYSTOLIC_ARRAY_LENGTH-1] <= 32'd0;

+						pe_t_mem[SYSTOLIC_ARRAY_LENGTH-1][syst_cnt_last] <= 32'd0;

 					

 				end

 			end

@@ -861,8 +866,8 @@ module modexpa7_systolic_multiplier #
 				if (shreg_now_loading) begin

 					pe_a[j]		<= (ab_addr_ext > {1'b0, a_addr}) ? 32'd0 : a_bram_out;

 					pe_b[j]		<= loader_dout[j];

-					pe_t[j]		<= (a_addr == bram_addr_zero) ? 32'd0 : pe_t_mem[syst_cnt_load_dly][j];

-					pe_c_in[j]	<= (a_addr == bram_addr_zero) ? 32'd0 : pe_c_out_mem[syst_cnt_load_dly][j];

+					pe_t[j]		<= (a_addr == bram_addr_zero) ? 32'd0 : pe_t_mem[j][syst_cnt_load_dly];

+					pe_c_in[j]	<= (a_addr == bram_addr_zero) ? 32'd0 : pe_c_out_mem[j][syst_cnt_load_dly];

 				end else begin

 					pe_a[j]		<= 32'hXXXXXXXX;				

 					pe_b[j]		<= 32'hXXXXXXXX;

@@ -877,8 +882,8 @@ module modexpa7_systolic_multiplier #
 				if (shreg_now_loading) begin

 					pe_a[j]		<= ab_data_out;

 					pe_b[j]		<= loader_dout[j];

-					pe_t[j]		<= (ab_addr_ext == bram_addr_ext_zero) ? 32'd0 : pe_t_mem[syst_cnt_load_dly][j];

-					pe_c_in[j]	<= (ab_addr_ext == bram_addr_ext_zero) ? 32'd0 : pe_c_out_mem[syst_cnt_load_dly][j];

+					pe_t[j]		<= (ab_addr_ext == bram_addr_ext_zero) ? 32'd0 : pe_t_mem[j][syst_cnt_load_dly];

+					pe_c_in[j]	<= (ab_addr_ext == bram_addr_ext_zero) ? 32'd0 : pe_c_out_mem[j][syst_cnt_load_dly];

 				end else begin

 					pe_a[j]		<= 32'hXXXXXXXX;				

 					pe_b[j]		<= 32'hXXXXXXXX;

@@ -893,8 +898,8 @@ module modexpa7_systolic_multiplier #
 				if (shreg_now_loading) begin

 					pe_a[j]		<= (qn_addr_ext > {1'b0, q_addr}) ? 32'd0 : q_data_out;

 					pe_b[j]		<= loader_dout[j];

-					pe_t[j]		<= (q_addr == bram_addr_zero) ? 32'd0 : pe_t_mem[syst_cnt_load_dly][j];

-					pe_c_in[j]	<= (q_addr == bram_addr_zero) ? 32'd0 : pe_c_out_mem[syst_cnt_load_dly][j];

+					pe_t[j]		<= (q_addr == bram_addr_zero) ? 32'd0 : pe_t_mem[j][syst_cnt_load_dly];

+					pe_c_in[j]	<= (q_addr == bram_addr_zero) ? 32'd0 : pe_c_out_mem[j][syst_cnt_load_dly];

 				end else begin

 					pe_a[j]		<= 32'hXXXXXXXX;				

 					pe_b[j]		<= 32'hXXXXXXXX;