//======================================================================
//
// Copyright (c) 2018, NORDUnet A/S All rights reserved.
//
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//
// - Redistributions in binary form must reproduce the above copyright
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// without specific prior written permission.
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// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
//======================================================================
`timescale 1ns / 1ps
module ecdhp256
(
input wire clk,
input wire rst_n,
input wire next,
output wire valid,
input wire bus_cs,
input wire bus_we,
input wire [ 5:0] bus_addr,
input wire [31:0] bus_data_wr,
output wire [31:0] bus_data_rd
);
//
// Memory Banks
//
localparam [2:0] BUS_ADDR_BANK_K = 3'd0;
localparam [2:0] BUS_ADDR_BANK_IN_X = 3'd1;
localparam [2:0] BUS_ADDR_BANK_IN_Y = 3'd2;
localparam [2:0] BUS_ADDR_BANK_OUT_X = 3'd3;
localparam [2:0] BUS_ADDR_BANK_OUT_Y = 3'd4;
wire [2:0] bus_addr_upper = bus_addr[5:3];
wire [2:0] bus_addr_lower = bus_addr[2:0];
//
// Memories
//
wire [31:0] user_rw_k_bram_out;
wire [31:0] user_rw_in_x_bram_out;
wire [31:0] user_rw_in_y_bram_out;
wire [31:0] user_ro_out_x_bram_out;
wire [31:0] user_ro_out_y_bram_out;
wire [ 2:0] core_ro_k_bram_addr;
wire [ 2:0] core_ro_in_x_bram_addr;
wire [ 2:0] core_ro_in_y_bram_addr;
wire [ 2:0] core_rw_out_x_bram_addr;
wire [ 2:0] core_rw_out_y_bram_addr;
wire core_rw_out_x_bram_wren;
wire core_rw_out_y_bram_wren;
wire [31:0] core_ro_k_bram_dout;
wire [31:0] core_ro_in_x_bram_dout;
wire [31:0] core_ro_in_y_bram_dout;
wire [31:0] core_rw_out_x_bram_din;
wire [31:0] core_rw_out_y_bram_din;
bram_1rw_1ro_readfirst #
( .MEM_WIDTH(32), .MEM_ADDR_BITS(3)
)
bram_k
( .clk(clk),
.a_addr(bus_addr_lower), .a_out(user_rw_k_bram_out), .a_wr(bus_cs && bus_we && (bus_addr_upper == BUS_ADDR_BANK_K)), .a_in(bus_data_wr),
.b_addr(core_ro_k_bram_addr), .b_out(core_ro_k_bram_dout)
);
bram_1rw_1ro_readfirst #
( .MEM_WIDTH(32), .MEM_ADDR_BITS(3)
)
bram_in_x
( .clk(clk),
.a_addr(bus_addr_lower), .a_out(user_rw_in_x_bram_out), .a_wr(bus_cs && bus_we && (bus_addr_upper == BUS_ADDR_BANK_IN_X)), .a_in(bus_data_wr),
.b_addr(core_ro_in_x_bram_addr), .b_out(core_ro_in_x_bram_dout)
);
bram_1rw_1ro_readfirst #
( .MEM_WIDTH(32), .MEM_ADDR_BITS(3)
)
bram_in_y
( .clk(clk),
.a_addr(bus_addr_lower), .a_out(user_rw_in_y_bram_out), .a_wr(bus_cs && bus_we && (bus_addr_upper == BUS_ADDR_BANK_IN_Y)), .a_in(bus_data_wr),
.b_addr(core_ro_in_y_bram_addr), .b_out(core_ro_in_y_bram_dout)
);
bram_1rw_1ro_readfirst #
( .MEM_WIDTH(32), .MEM_ADDR_BITS(3)
)
bram_out_x
( .clk(clk),
.a_addr(core_rw_out_x_bram_addr), .a_out(), .a_wr(core_rw_out_x_bram_wren), .a_in(core_rw_out_x_bram_din),
.b_addr(bus_addr_lower), .b_out(user_ro_out_x_bram_out)
);
bram_1rw_1ro_readfirst #
( .MEM_WIDTH(32), .MEM_ADDR_BITS(3)
)
bram_out_y
( .clk(clk),
.a_addr(core_rw_out_y_bram_addr), .a_out(), .a_wr(core_rw_out_y_bram_wren), .a_in(core_rw_out_y_bram_din),
.b_addr(bus_addr_lower), .b_out(user_ro_out_y_bram_out)
);
//
// Curve Point Multiplier
//
reg next_dly;
always @(posedge clk) next_dly <= next;
wire next_trig = next && !next_dly;
point_mul_256 point_multiplier_p256
(
.clk (clk),
.rst_n (rst_n),
.ena (next_trig),
.rdy (valid),
.k_addr (core_ro_k_bram_addr),
.qx_addr (core_ro_in_x_bram_addr),
.qy_addr (core_ro_in_y_bram_addr),
.rx_addr (core_rw_out_x_bram_addr),
.ry_addr (core_rw_out_y_bram_addr),
.rx_wren (core_rw_out_x_bram_wren),
.ry_wren (core_rw_out_y_bram_wren),
.k_din (core_ro_k_bram_dout),
.qx_din (core_ro_in_x_bram_dout),
.qy_din (core_ro_in_y_bram_dout),
.rx_dout (core_rw_out_x_bram_din),
.ry_dout (core_rw_out_y_bram_din)
);
//
// Output Selector
//
reg [2:0] bus_addr_upper_prev;
always @(posedge clk) bus_addr_upper_prev = bus_addr_upper;
reg [31: 0] bus_data_rd_mux;
assign bus_data_rd = bus_data_rd_mux;
always @(*)
//
case (bus_addr_upper_prev)
//
BUS_ADDR_BANK_K: bus_data_rd_mux = user_rw_k_bram_out;
BUS_ADDR_BANK_IN_X: bus_data_rd_mux = user_rw_in_x_bram_out;
BUS_ADDR_BANK_IN_Y: bus_data_rd_mux = user_rw_in_y_bram_out;
BUS_ADDR_BANK_OUT_X: bus_data_rd_mux = user_ro_out_x_bram_out;
BUS_ADDR_BANK_OUT_Y: bus_data_rd_mux = user_ro_out_y_bram_out;
//
default: bus_data_rd_mux = {32{1'b0}};
//
endcase
endmodule
