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authorJoachim StroĢˆmbergson <joachim@secworks.se>2015-04-20 09:44:48 +0200
committerJoachim StroĢˆmbergson <joachim@secworks.se>2015-04-20 09:44:48 +0200
commitde85f39e57b28d38cd565804862ef828f071d730 (patch)
treee87466a62fae4c38678676525a842aef928ac1b7 /src
parentd4a4552b9e786f022161028ed869b283f972e4ee (diff)
(1) Modexp with better API. (2) Adding working residue module. (3) Adding new shift32 with carry module needed by the residue module.
Diffstat (limited to 'src')
-rw-r--r--src/rtl/modexp.v155
-rw-r--r--src/rtl/residue.v273
-rw-r--r--src/rtl/shl32.v53
3 files changed, 373 insertions, 108 deletions
diff --git a/src/rtl/modexp.v b/src/rtl/modexp.v
index b0e8aa3..8721ce9 100644
--- a/src/rtl/modexp.v
+++ b/src/rtl/modexp.v
@@ -17,10 +17,10 @@
//
// The core has a 32-bit memory like interface, but provides
// status signals to inform the system that a given operation
-// has is done. Additionally, any errors will also be asserted.
+// has completed. Additionally, any errors will also be asserted.
//
//
-// Author: Peter Magnusson, Joachim Strombergson
+// Author: Joachim Strombergson, Peter Magnusson
// Copyright (c) 2015, NORDUnet A/S All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
@@ -72,8 +72,15 @@ module modexp(
localparam ADDR_NAME1 = 8'h01;
localparam ADDR_VERSION = 8'h02;
- localparam ADDR_MODSIZE = 8'h10;
- localparam ADDR_EXPONENT = 8'h20;
+ localparam ADDR_CTRL = 8'h00;
+ localparam CTRL_INIT_BIT = 0;
+ localparam CTRL_NEXT_BIT = 1;
+
+ localparam ADDR_STATUS = 8'h09;
+
+ localparam ADDR_MODSIZE = 8'h20;
+ localparam ADDR_LENGTH = 8'h21;
+ localparam ADDR_EXPONENT = 8'h22;
localparam MODULUS_PREFIX = 4'h1;
localparam ADDR_MODULUS_START = 8'h00;
@@ -117,8 +124,8 @@ module modexp(
localparam CTRL_CALCULATE_ZN = 4'h8;
localparam CTRL_DONE = 4'h9;
- localparam CORE_NAME0 = 32'h72736120; // "rsa "
- localparam CORE_NAME1 = 32'h38313932; // "8192"
+ localparam CORE_NAME0 = 32'h6d6f6465; // "mode"
+ localparam CORE_NAME1 = 32'h78702020; // "xp "
localparam CORE_VERSION = 32'h302e3031; // "0.01"
@@ -309,15 +316,15 @@ module modexp(
);
blockmem2r1w p_mem(
- .clk(clk),
- .read_addr0(p_mem_rd0_addr),
- .read_data0(p_mem_rd0_data),
- .read_addr1(p_mem_rd1_addr),
- .read_data1(p_mem_rd1_data),
- .wr(p_mem_we),
- .write_addr(p_mem_wr_addr),
- .write_data(p_mem_wr_data)
- );
+ .clk(clk),
+ .read_addr0(p_mem_rd0_addr),
+ .read_data0(p_mem_rd0_data),
+ .read_addr1(p_mem_rd1_addr),
+ .read_data1(p_mem_rd1_data),
+ .wr(p_mem_we),
+ .write_addr(p_mem_wr_addr),
+ .write_data(p_mem_wr_data)
+ );
//----------------------------------------------------------------
@@ -357,8 +364,8 @@ module modexp(
if (length_we)
begin
- length_reg <= length_new;
- length_m1_reg <= length_m1_new;
+ length_reg <= write_data[7 : 0];
+ length_m1_reg <= write_data[7 : 0] - 8'h1;
end
if (loop_counter_we)
@@ -382,67 +389,51 @@ module modexp(
modulus_mem_api_we = 1'b0;
exponent_mem_api_we = 1'b0;
message_mem_api_we = 1'b0;
+ length_we = 1'b0;
tmp_read_data = 32'h00000000;
- length_new = write_data[7 : 0];
- length_m1_new = write_data[7 : 0] - 8'h1;
- length_we = 1'b0;
-
if (cs)
begin
case (address[11 : 8])
GENERAL_PREFIX:
begin
-// if (we)
-// begin
-// case (address)
-// // Write operations.
-// ADDR_MODSIZE:
-// begin
-// modsize_we = 1;
-// end
-//
-// ADDR_EXPONENT:
-// begin
-// exponent_we = 1;
-// end
-//
-// default:
-// begin
-// tmp_error = 1;
-// end
-// endcase // case (addr)
-// end // if (write_read)
-// else
-// begin
-// case (address)
-// // Read operations.
-// ADDR_NAME0:
-// begin
-// tmp_read_data = CORE_NAME0;
-// end
-//
-// ADDR_NAME1:
-// begin
-// tmp_read_data = CORE_NAME1;
-// end
-//
-// ADDR_VERSION:
-// begin
-// tmp_read_data = CORE_VERSION;
-// end
-//
-// ADDR_MODSIZE:
-// begin
-// tmp_read_data = {28'h0000000, modsize_reg};
-// end
-//
-// default:
-// begin
-// tmp_error = 1;
-// end
-// endcase // case (addr)
-// end
+ if (we)
+ begin
+ case (address[7 : 0])
+ ADDR_LENGTH:
+ length_we = 1'b1;
+
+ default:
+ begin
+ end
+ endcase // case (address[7 : 0])
+ end
+ else
+ begin
+ case (address[7 : 0])
+ ADDR_NAME0:
+ tmp_read_data = CORE_NAME0;
+
+ ADDR_NAME1:
+ tmp_read_data = CORE_NAME1;
+
+ ADDR_VERSION:
+ tmp_read_data = CORE_VERSION;
+
+ ADDR_CTRL:
+ tmp_read_data = 32'h00000000;
+
+ ADDR_STATUS:
+ tmp_read_data = 32'h00000000;
+
+ ADDR_LENGTH:
+ tmp_read_data = {24'h000000, length_reg};
+
+ default:
+ begin
+ end
+ endcase // case (address[7 : 0])
+ end
end
MODULUS_PREFIX:
@@ -486,24 +477,6 @@ module modexp(
tmp_read_data = result_mem_api_rd_data;
end
- LENGTH_PREFIX:
- begin
- if (we)
- length_we = 1'b1;
- end
-
-// RESULT_PREFIX:
-// begin
-// if (we)
-// begin
-// modulus_mem_api_we = 1'b1;
-// end
-// else
-// begin
-// tmp_read_data = modulus_mem_int_rd_data;
-// end
-// end
-
default:
begin
@@ -574,6 +547,7 @@ module modexp(
endcase // case (montprod_selcect_reg)
end
+
//----------------------------------------------------------------
// memory write mux
//
@@ -604,6 +578,7 @@ module modexp(
result_mem_int_we = result_mem_int_we & ei_reg;
end
+
//----------------------------------------------------------------
// loop_counter
//
@@ -640,6 +615,7 @@ module modexp(
endcase
end
+
//----------------------------------------------------------------
// exponent
//
@@ -660,6 +636,7 @@ module modexp(
ei_we = 1'b0;
end
+
//----------------------------------------------------------------
// modexp_ctrl
//
diff --git a/src/rtl/residue.v b/src/rtl/residue.v
index 2991dd6..3fa1666 100644
--- a/src/rtl/residue.v
+++ b/src/rtl/residue.v
@@ -52,7 +52,7 @@ module residue(
input wire calculate,
output wire ready,
- input wire [07 : 0] nn,
+ input wire [14 : 0] nn, //MAX(2*N)=8192*2 (14 bit)
input wire [07 : 0] length,
output wire [07 : 0] opa_rd_addr,
@@ -71,16 +71,24 @@ module residue(
//----------------------------------------------------------------
+// m_residue_2_2N_array( N, M, Nr)
+// Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
+// for (int i = 0; i < 2 * N; i++)
+// Nr = Nr shift left 1
+// if (Nr less than M) continue;
+// Nr = Nr - M
+// return Nr
+//
localparam CTRL_IDLE = 4'h0;
-localparam CTRL_INIT = 4'h1;
+localparam CTRL_INIT = 4'h1; // Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
localparam CTRL_INIT_STALL = 4'h2;
-localparam CTRL_SHL = 4'h3;
+localparam CTRL_SHL = 4'h3; // Nr = Nr shift left 1
localparam CTRL_SHL_STALL = 4'h4;
-localparam CTRL_COMPARE = 4'h5;
+localparam CTRL_COMPARE = 4'h5; //if (Nr less than M) continue;
localparam CTRL_COMPARE_STALL = 4'h6;
-localparam CTRL_SUB = 4'h7;
+localparam CTRL_SUB = 4'h7; //Nr = Nr - M
localparam CTRL_SUB_STALL = 4'h8;
-localparam CTRL_LOOP = 4'h9;
+localparam CTRL_LOOP = 4'h9; //for (int i = 0; i < 2 * N; i++)
//----------------------------------------------------------------
// Registers including update variables and write enable.
@@ -99,7 +107,27 @@ reg [03 : 0] residue_ctrl_new;
reg residue_ctrl_we;
reg reset_word_index;
reg reset_n_counter;
-reg [07 : 0] word_index;
+reg [14 : 0] loop_counter_1_to_nn_reg; //for i = 1 to nn (2*N)
+reg [14 : 0] loop_counter_1_to_nn_new;
+reg loop_counter_1_to_nn_we;
+reg [14 : 0] nn_reg;
+reg nn_we;
+reg [07 : 0] length_m1_reg;
+reg [07 : 0] length_m1_new;
+reg length_m1_we;
+reg [07 : 0] word_index_reg;
+reg [07 : 0] word_index_new;
+reg word_index_we;
+
+reg [31 : 0] one_data;
+wire [31 : 0] sub_data;
+wire [31 : 0] shl_data;
+reg sub_carry_in_new;
+reg sub_carry_in_reg;
+wire sub_carry_out;
+reg shl_carry_in_new;
+reg shl_carry_in_reg;
+wire shl_carry_out;
//----------------------------------------------------------------
// Concurrent connectivity for ports etc.
@@ -107,10 +135,29 @@ reg [07 : 0] word_index;
assign opa_rd_addr = opa_rd_addr_reg;
assign opa_wr_addr = opa_wr_addr_reg;
assign opa_wr_data = opa_wr_data_reg;
+assign opa_wr_we = opa_wr_we_reg;
assign opm_addr = opm_addr_reg;
assign ready = ready_reg;
+ //----------------------------------------------------------------
+ // Instantions
+ //----------------------------------------------------------------
+ adder32 subcmp(
+ .a(opa_rd_data),
+ .b( ~ opm_data),
+ .carry_in(sub_carry_in_reg),
+ .sum(sub_data),
+ .carry_out(sub_carry_out)
+ );
+
+ shl32 shl(
+ .a(opa_rd_data),
+ .carry_in(shl_carry_in_reg),
+ .amul2(shl_data),
+ .carry_out(shl_carry_out)
+ );
+
//----------------------------------------------------------------
@@ -121,25 +168,168 @@ assign ready = ready_reg;
if (!reset_n)
begin
residue_ctrl_reg <= CTRL_IDLE;
+ word_index_reg <= 8'h0;
+ length_m1_reg <= 8'h0;
+ nn_reg <= 15'h0;
+ loop_counter_1_to_nn_reg <= 15'h0;
+ ready_reg <= 1'b1;
+ sub_carry_in_reg <= 1'b0;
+ shl_carry_in_reg <= 1'b0;
end
else
begin
if (residue_ctrl_we)
residue_ctrl_reg <= residue_ctrl_new;
+
+ if (word_index_we)
+ word_index_reg <= word_index_new;
+
+ if (length_m1_we)
+ length_m1_reg <= length_m1_new;
+
+ if (nn_we)
+ nn_reg <= nn;
+
+ if (loop_counter_1_to_nn_we)
+ loop_counter_1_to_nn_reg <= loop_counter_1_to_nn_new;
+
+ if (ready_we)
+ ready_reg <= ready_new;
+
+ sub_carry_in_reg <= sub_carry_in_new;
+ shl_carry_in_reg <= shl_carry_in_new;
end
end // reg_update
//----------------------------------------------------------------
+ // loop counter process. implements for (int i = 0; i < 2 * N; i++)
+ //
+ // m_residue_2_2N_array( N, M, Nr)
+ // Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
+ // for (int i = 0; i < 2 * N; i++)
+ // Nr = Nr shift left 1
+ // if (Nr less than M) continue;
+ // Nr = Nr - M
+ // return Nr
+ //
//----------------------------------------------------------------
always @*
begin : process_1_to_2n
+ loop_counter_1_to_nn_new = loop_counter_1_to_nn_reg + 15'h1;
+ loop_counter_1_to_nn_we = 1'b0;
+
+ if (reset_n_counter)
+ begin
+ loop_counter_1_to_nn_new = 15'h1;
+ loop_counter_1_to_nn_we = 1'b1;
+ end
+
+ if (residue_ctrl_reg == CTRL_LOOP)
+ loop_counter_1_to_nn_we = 1'b1;
end
//----------------------------------------------------------------
+ // implements looping over words in a multiword operation
//----------------------------------------------------------------
always @*
begin : word_index_process
+ word_index_new = word_index_reg - 8'h1;
+ word_index_we = 1'b1;
+
+ if (reset_word_index)
+ word_index_new = length_m1_reg;
+
+ if (residue_ctrl_reg == CTRL_IDLE)
+ word_index_new = length_m1_new; //reduce a pipeline stage with early read
+
+ end
+
+ //----------------------------------------------------------------
+ // writer process. implements:
+ // Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
+ // Nr = Nr shift left 1
+ // Nr = Nr - M
+ //
+ // m_residue_2_2N_array( N, M, Nr)
+ // Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
+ // for (int i = 0; i < 2 * N; i++)
+ // Nr = Nr shift left 1
+ // if (Nr less than M) continue;
+ // Nr = Nr - M
+ // return Nr
+ //----------------------------------------------------------------
+ always @*
+ begin : writer_process
+ opa_wr_addr_reg = word_index_reg;
+ case (residue_ctrl_reg)
+ CTRL_INIT:
+ begin
+ opa_wr_data_reg = one_data;
+ opa_wr_we_reg = 1'b1;
+ end
+
+ CTRL_SUB:
+ begin
+ opa_wr_data_reg = sub_data;
+ opa_wr_we_reg = 1'b1;
+ end
+
+ CTRL_SHL:
+ begin
+ opa_wr_data_reg = shl_data;
+ opa_wr_we_reg = 1'b1;
+ end
+
+ default:
+ begin
+ opa_wr_data_reg = 32'h0;
+ opa_wr_we_reg = 1'b0;
+ end
+ endcase
+ end
+
+ //----------------------------------------------------------------
+ // reader process. reads from new value because it occurs one
+ // cycle earlier than the writer.
+ //----------------------------------------------------------------
+ always @*
+ begin : reader_process
+ opa_rd_addr_reg = word_index_new;
+ opm_addr_reg = word_index_new;
+ end
+
+ //----------------------------------------------------------------
+ // carry process. "Ripple carry awesomeness!"
+ //----------------------------------------------------------------
+ always @*
+ begin : carry_process
+ case (residue_ctrl_reg)
+ CTRL_COMPARE:
+ sub_carry_in_new = sub_carry_out;
+ CTRL_SUB:
+ sub_carry_in_new = sub_carry_out;
+ default:
+ sub_carry_in_new = 1'b1;
+ endcase
+
+ case (residue_ctrl_reg)
+ CTRL_SHL:
+ shl_carry_in_new = shl_carry_out;
+ default:
+ shl_carry_in_new = 1'b0;
+ endcase
+ end
+
+ //----------------------------------------------------------------
+ // Nr = 00...01 ; Nr = 1 == 2**(2N-2N)
+ //----------------------------------------------------------------
+ always @*
+ begin : one_process
+ one_data = 32'h0;
+ if (residue_ctrl_reg == CTRL_INIT)
+ if (word_index_reg == length_m1_reg)
+ one_data = 32'h1;
end
//----------------------------------------------------------------
@@ -151,11 +341,18 @@ always @*
begin : residue_ctrl
ready_new = 1'b0;
ready_we = 1'b0;
+
residue_ctrl_new = CTRL_IDLE;
residue_ctrl_we = 1'b0;
+
reset_word_index = 1'b0;
reset_n_counter = 1'b0;
+ length_m1_new = length - 8'h1;
+ length_m1_we = 1'b0;
+
+ nn_we = 1'b0;
+
case (residue_ctrl_reg)
CTRL_IDLE:
if (calculate)
@@ -165,10 +362,12 @@ always @*
residue_ctrl_new = CTRL_INIT;
residue_ctrl_we = 1'b1;
reset_word_index = 1'b1;
+ length_m1_we = 1'b1;
+ nn_we = 1'b1;
end
CTRL_INIT:
- if (word_index == 8'h0)
+ if (word_index_reg == 8'h0)
begin
residue_ctrl_new = CTRL_INIT_STALL;
residue_ctrl_we = 1'b1;
@@ -178,36 +377,72 @@ always @*
begin
reset_word_index = 1'b1;
reset_n_counter = 1'b1;
- residue_ctrl_new = CTRL_COMPARE;
+ residue_ctrl_new = CTRL_SHL;
residue_ctrl_we = 1'b1;
end
- CTRL_COMPARE:
+ CTRL_SHL:
begin
+ if (word_index_reg == 8'h0)
+ begin
+ residue_ctrl_new = CTRL_SHL_STALL;
+ residue_ctrl_we = 1'b1;
+ end
end
- CTRL_COMPARE_STALL:
+ CTRL_SHL_STALL:
begin
+ reset_word_index = 1'b1;
+ residue_ctrl_new = CTRL_COMPARE;
+ residue_ctrl_we = 1'b1;
end
- CTRL_SUB:
- begin
- end
+ CTRL_COMPARE:
+ if (word_index_reg == 8'h0)
+ begin
+ residue_ctrl_new = CTRL_COMPARE_STALL;
+ residue_ctrl_we = 1'b1;
+ end
- CTRL_SUB_STALL:
+ CTRL_COMPARE_STALL:
begin
+ reset_word_index = 1'b1;
+ residue_ctrl_we = 1'b1;
+ if (sub_carry_in_reg == 1'b1)
+ //TODO: Bug! detect CF to detect less than, but no detect ZF to detect equal to.
+ residue_ctrl_new = CTRL_SUB;
+ else
+ residue_ctrl_new = CTRL_LOOP;
end
- CTRL_SHL:
- begin
- end
+ CTRL_SUB:
+ if (word_index_reg == 8'h0)
+ begin
+ residue_ctrl_new = CTRL_SUB_STALL;
+ residue_ctrl_we = 1'b1;
+ end
- CTRL_SHL_STALL:
+ CTRL_SUB_STALL:
begin
+ residue_ctrl_new = CTRL_LOOP;
+ residue_ctrl_we = 1'b1;
end
CTRL_LOOP:
begin
+ if (loop_counter_1_to_nn_reg == nn_reg)
+ begin
+ ready_new = 1'b1;
+ ready_we = 1'b1;
+ residue_ctrl_new = CTRL_IDLE;
+ residue_ctrl_we = 1'b1;
+ end
+ else
+ begin
+ reset_word_index = 1'b1;
+ residue_ctrl_new = CTRL_SHL;
+ residue_ctrl_we = 1'b1;
+ end
end
default:
diff --git a/src/rtl/shl32.v b/src/rtl/shl32.v
new file mode 100644
index 0000000..d0dd1bc
--- /dev/null
+++ b/src/rtl/shl32.v
@@ -0,0 +1,53 @@
+//======================================================================
+//
+// shr32.v
+// ---------
+// 32bit shifter with carry in / carry out.
+//
+//
+// Author: Peter Magnusson
+// Copyright (c) 2015, NORDUnet A/S All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// - Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+//
+// - Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// - Neither the name of the NORDUnet nor the names of its contributors may
+// be used to endorse or promote products derived from this software
+// without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+//======================================================================
+
+
+module shl32(
+ input [31 : 0] a,
+ input carry_in,
+ output wire [31 : 0] amul2,
+ output wire carry_out);
+
+ reg [32 : 0] shl_result;
+
+ assign amul2 = shl_result[31:0];
+ assign carry_out = shl_result[32];
+
+ always @(a, carry_in)
+ shl_result = { a, carry_in };
+endmodule