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authorPaul Selkirk <paul@psgd.org>2015-03-31 16:29:17 -0400
committerPaul Selkirk <paul@psgd.org>2015-03-31 16:29:17 -0400
commit9d5b0b9c28bfd3e5087a1481960d377ec3e47453 (patch)
tree96c1e7f6081bac263bcdf8764f5fd130f94fc644 /src/rtl
parent4b6331236597049ab17e7dee72e3b35d67015895 (diff)
Revert streamlined wrapper, and don't delay register reads.
Diffstat (limited to 'src/rtl')
-rw-r--r--src/rtl/sha256.v834
1 files changed, 648 insertions, 186 deletions
diff --git a/src/rtl/sha256.v b/src/rtl/sha256.v
index 04048b1..a7d3518 100644
--- a/src/rtl/sha256.v
+++ b/src/rtl/sha256.v
@@ -1,204 +1,666 @@
//======================================================================
//
// sha256.v
-// ------
+// --------
// Top level wrapper for the SHA-256 hash function providing
// a simple memory like interface with 32 bit data access.
//
-// Authors: Joachim Strömbergson, Paul Selkirk
-// Copyright (c) 2014-2015, 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.
+// Author: Joachim Strombergson
+// Copyright (c) 2014, SUNET
+// All rights reserved.
//
-// - 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.
+// Redistribution and use in source and binary forms, with or
+// without modification, are permitted provided that the following
+// conditions are met:
//
-// 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.
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//
+// 2. 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.
+//
+// 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 OWNER 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 sha256(
- // Clock and reset.
- input wire clk,
- input wire reset_n,
-
- // Control.
- input wire cs,
- input wire we,
-
- // Data ports.
- input wire [7 : 0] address,
- input wire [31 : 0] write_data,
- output wire [31 : 0] read_data
- );
-
- //----------------------------------------------------------------
- // Internal constant and parameter definitions.
- //----------------------------------------------------------------
- parameter ADDR_NAME0 = 8'h00;
- parameter ADDR_NAME1 = 8'h01;
- parameter ADDR_VERSION = 8'h02;
-
- parameter ADDR_CTRL = 8'h08;
- parameter CTRL_INIT_BIT = 0;
- parameter CTRL_NEXT_BIT = 1;
-
- parameter ADDR_STATUS = 8'h09;
- parameter STATUS_READY_BIT = 0;
- parameter STATUS_VALID_BIT = 1;
-
- parameter ADDR_BLOCK = 8'h10;
-
- parameter ADDR_DIGEST = 8'h20;
-
- parameter CORE_NAME0 = 32'h73686132; // "sha2"
- parameter CORE_NAME1 = 32'h2d323536; // "-256"
- parameter CORE_VERSION = 32'h302e3830; // "0.80"
-
- parameter BLOCK_BITS = 512;
- parameter DIGEST_BITS = 256;
- parameter BLOCK_WORDS = BLOCK_BITS / 32;
- parameter DIGEST_WORDS = DIGEST_BITS / 32;
-
- //----------------------------------------------------------------
- // Registers.
- //----------------------------------------------------------------
- reg [0 : BLOCK_BITS - 1] block_reg;
- reg [0 : DIGEST_BITS - 1] digest_reg;
- reg init_reg;
- reg next_reg;
-
- reg [31 : 0] tmp_read_data;
- reg [31 : 0] tmp_read_data_reg;
-
- //----------------------------------------------------------------
- // Wires.
- //----------------------------------------------------------------
- wire core_init;
- wire core_next;
- wire core_ready;
- wire [0 : BLOCK_BITS - 1] core_block;
- wire [0 : DIGEST_BITS - 1] core_digest;
- wire core_digest_valid;
-
- wire [31 : 0] core_name0 = CORE_NAME0;
- wire [31 : 0] core_name1 = CORE_NAME1;
- wire [31 : 0] core_version = CORE_VERSION;
- wire [31 : 0] core_ctrl;
- wire [31 : 0] core_status;
-
- //----------------------------------------------------------------
- // Concurrent connectivity for ports etc.
- //----------------------------------------------------------------
- assign core_init = init_reg;
- assign core_next = next_reg;
- assign core_ctrl = { 30'b0, next_reg, init_reg };
- assign core_status = { 30'b0, core_digest_valid, core_ready };
- assign core_block = block_reg;
-
- assign read_data = tmp_read_data_reg;
-
- //----------------------------------------------------------------
- // core instantiation.
- //----------------------------------------------------------------
- sha256_core core(
- .clk(clk),
- .reset_n(reset_n),
-
- .init(core_init),
- .next(core_next),
-
- .block(core_block),
-
- .ready(core_ready),
-
- .digest(core_digest),
- .digest_valid(core_digest_valid)
+ // Clock and reset.
+ input wire clk,
+ input wire reset_n,
+
+ // Control.
+ input wire cs,
+ input wire we,
+
+ // Data ports.
+ input wire [7 : 0] address,
+ input wire [31 : 0] write_data,
+ output wire [31 : 0] read_data,
+ output wire error
+ );
+
+ //----------------------------------------------------------------
+ // Internal constant and parameter definitions.
+ //----------------------------------------------------------------
+ parameter ADDR_NAME0 = 8'h00;
+ parameter ADDR_NAME1 = 8'h01;
+ parameter ADDR_VERSION = 8'h02;
+
+ parameter ADDR_CTRL = 8'h08;
+ parameter CTRL_INIT_BIT = 0;
+ parameter CTRL_NEXT_BIT = 1;
+
+ parameter ADDR_STATUS = 8'h09;
+ parameter STATUS_READY_BIT = 0;
+ parameter STATUS_VALID_BIT = 1;
+
+ parameter ADDR_BLOCK0 = 8'h10;
+ parameter ADDR_BLOCK1 = 8'h11;
+ parameter ADDR_BLOCK2 = 8'h12;
+ parameter ADDR_BLOCK3 = 8'h13;
+ parameter ADDR_BLOCK4 = 8'h14;
+ parameter ADDR_BLOCK5 = 8'h15;
+ parameter ADDR_BLOCK6 = 8'h16;
+ parameter ADDR_BLOCK7 = 8'h17;
+ parameter ADDR_BLOCK8 = 8'h18;
+ parameter ADDR_BLOCK9 = 8'h19;
+ parameter ADDR_BLOCK10 = 8'h1a;
+ parameter ADDR_BLOCK11 = 8'h1b;
+ parameter ADDR_BLOCK12 = 8'h1c;
+ parameter ADDR_BLOCK13 = 8'h1d;
+ parameter ADDR_BLOCK14 = 8'h1e;
+ parameter ADDR_BLOCK15 = 8'h1f;
+
+ parameter ADDR_DIGEST0 = 8'h20;
+ parameter ADDR_DIGEST1 = 8'h21;
+ parameter ADDR_DIGEST2 = 8'h22;
+ parameter ADDR_DIGEST3 = 8'h23;
+ parameter ADDR_DIGEST4 = 8'h24;
+ parameter ADDR_DIGEST5 = 8'h25;
+ parameter ADDR_DIGEST6 = 8'h26;
+ parameter ADDR_DIGEST7 = 8'h27;
+
+ parameter CORE_NAME0 = 32'h73686132; // "sha2"
+ parameter CORE_NAME1 = 32'h2d323536; // "-256"
+ parameter CORE_VERSION = 32'h302e3830; // "0.80"
+
+
+ //----------------------------------------------------------------
+ // Registers including update variables and write enable.
+ //----------------------------------------------------------------
+ reg init_reg;
+ reg init_new;
+ reg init_we;
+ reg init_set;
+
+ reg next_reg;
+ reg next_new;
+ reg next_we;
+ reg next_set;
+
+ reg ready_reg;
+
+ reg [31 : 0] block0_reg;
+ reg block0_we;
+ reg [31 : 0] block1_reg;
+ reg block1_we;
+ reg [31 : 0] block2_reg;
+ reg block2_we;
+ reg [31 : 0] block3_reg;
+ reg block3_we;
+ reg [31 : 0] block4_reg;
+ reg block4_we;
+ reg [31 : 0] block5_reg;
+ reg block5_we;
+ reg [31 : 0] block6_reg;
+ reg block6_we;
+ reg [31 : 0] block7_reg;
+ reg block7_we;
+ reg [31 : 0] block8_reg;
+ reg block8_we;
+ reg [31 : 0] block9_reg;
+ reg block9_we;
+ reg [31 : 0] block10_reg;
+ reg block10_we;
+ reg [31 : 0] block11_reg;
+ reg block11_we;
+ reg [31 : 0] block12_reg;
+ reg block12_we;
+ reg [31 : 0] block13_reg;
+ reg block13_we;
+ reg [31 : 0] block14_reg;
+ reg block14_we;
+ reg [31 : 0] block15_reg;
+ reg block15_we;
+
+ reg [255 : 0] digest_reg;
+
+ reg digest_valid_reg;
+
+
+ //----------------------------------------------------------------
+ // Wires.
+ //----------------------------------------------------------------
+ wire core_init;
+ wire core_next;
+ wire core_ready;
+ wire [511 : 0] core_block;
+ wire [255 : 0] core_digest;
+ wire core_digest_valid;
+
+ reg [31 : 0] tmp_read_data;
+ reg tmp_error;
+
+
+ //----------------------------------------------------------------
+ // Concurrent connectivity for ports etc.
+ //----------------------------------------------------------------
+ assign core_init = init_reg;
+
+ assign core_next = next_reg;
+
+ assign core_block = {block0_reg, block1_reg, block2_reg, block3_reg,
+ block4_reg, block5_reg, block6_reg, block7_reg,
+ block8_reg, block9_reg, block10_reg, block11_reg,
+ block12_reg, block13_reg, block14_reg, block15_reg};
+
+ assign read_data = tmp_read_data;
+ assign error = tmp_error;
+
+
+ //----------------------------------------------------------------
+ // core instantiation.
+ //----------------------------------------------------------------
+ sha256_core core(
+ .clk(clk),
+ .reset_n(reset_n),
+
+ .init(core_init),
+ .next(core_next),
+
+ .block(core_block),
+
+ .ready(core_ready),
+
+ .digest(core_digest),
+ .digest_valid(core_digest_valid)
);
- //----------------------------------------------------------------
- // latch in digest when ready
- //----------------------------------------------------------------
- always @(posedge clk)
- begin
- if (core_digest_valid)
- digest_reg <= core_digest;
- end
-
- //----------------------------------------------------------------
- // storage registers for mapping memory to core interface
- //----------------------------------------------------------------
- always @(posedge clk)
- begin
- init_reg <= 0;
- next_reg <= 0;
-
- if (cs && we)
- begin
- // write operations
- if ((address >= ADDR_BLOCK) &&
- (address < ADDR_BLOCK + BLOCK_WORDS))
- block_reg[((address - ADDR_BLOCK) * 32)+:32] <= write_data;
- else if (address == ADDR_CTRL)
- begin
- init_reg <= write_data[CTRL_INIT_BIT];
- next_reg <= write_data[CTRL_NEXT_BIT];
- end
- end
- end
-
- always @*
- begin
- tmp_read_data = 32'h00000000;
-
- if (cs && !we)
- begin
- // read operations
- if ((address >= ADDR_BLOCK) &&
- (address < ADDR_BLOCK + BLOCK_WORDS))
- tmp_read_data = block_reg[((address - ADDR_BLOCK) * 32)+:32];
- else if ((address >= ADDR_DIGEST) &&
- (address < ADDR_DIGEST + DIGEST_WORDS))
- tmp_read_data = digest_reg[((address - ADDR_DIGEST) * 32)+:32];
- else
- case (address)
- 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 = core_ctrl;
- ADDR_STATUS:
- tmp_read_data = core_status;
- endcase
- end
- end
-
- always @(posedge clk)
- begin
- tmp_read_data_reg <= tmp_read_data;
- end
+ //----------------------------------------------------------------
+ // reg_update
+ //
+ // Update functionality for all registers in the core.
+ // All registers are positive edge triggered with
+ // asynchronous active low reset.
+ //----------------------------------------------------------------
+ always @ (posedge clk or negedge reset_n)
+ begin
+ if (!reset_n)
+ begin
+ init_reg <= 0;
+ next_reg <= 0;
+ ready_reg <= 0;
+ digest_reg <= 256'h0000000000000000000000000000000000000000000000000000000000000000;
+ digest_valid_reg <= 0;
+ block0_reg <= 32'h00000000;
+ block1_reg <= 32'h00000000;
+ block2_reg <= 32'h00000000;
+ block3_reg <= 32'h00000000;
+ block4_reg <= 32'h00000000;
+ block5_reg <= 32'h00000000;
+ block6_reg <= 32'h00000000;
+ block7_reg <= 32'h00000000;
+ block8_reg <= 32'h00000000;
+ block9_reg <= 32'h00000000;
+ block10_reg <= 32'h00000000;
+ block11_reg <= 32'h00000000;
+ block12_reg <= 32'h00000000;
+ block13_reg <= 32'h00000000;
+ block14_reg <= 32'h00000000;
+ block15_reg <= 32'h00000000;
+ end
+ else
+ begin
+ ready_reg <= core_ready;
+ digest_valid_reg <= core_digest_valid;
+
+ if (init_we)
+ begin
+ init_reg <= init_new;
+ end
+
+ if (next_we)
+ begin
+ next_reg <= next_new;
+ end
+
+ if (core_digest_valid)
+ begin
+ digest_reg <= core_digest;
+ end
+
+ if (block0_we)
+ begin
+ block0_reg <= write_data;
+ end
+
+ if (block1_we)
+ begin
+ block1_reg <= write_data;
+ end
+
+ if (block2_we)
+ begin
+ block2_reg <= write_data;
+ end
+
+ if (block3_we)
+ begin
+ block3_reg <= write_data;
+ end
+
+ if (block4_we)
+ begin
+ block4_reg <= write_data;
+ end
+
+ if (block5_we)
+ begin
+ block5_reg <= write_data;
+ end
+
+ if (block6_we)
+ begin
+ block6_reg <= write_data;
+ end
+
+ if (block7_we)
+ begin
+ block7_reg <= write_data;
+ end
+
+ if (block8_we)
+ begin
+ block8_reg <= write_data;
+ end
+
+ if (block9_we)
+ begin
+ block9_reg <= write_data;
+ end
+
+ if (block10_we)
+ begin
+ block10_reg <= write_data;
+ end
+
+ if (block11_we)
+ begin
+ block11_reg <= write_data;
+ end
+
+ if (block12_we)
+ begin
+ block12_reg <= write_data;
+ end
+
+ if (block13_we)
+ begin
+ block13_reg <= write_data;
+ end
+
+ if (block14_we)
+ begin
+ block14_reg <= write_data;
+ end
+
+ if (block15_we)
+ begin
+ block15_reg <= write_data;
+ end
+
+ end
+ end // reg_update
+
+
+ //----------------------------------------------------------------
+ // flag_reset
+ //
+ // Logic to reset init and next flags that has been set.
+ //----------------------------------------------------------------
+ always @*
+ begin : flag_reset
+ init_new = 0;
+ init_we = 0;
+ next_new = 0;
+ next_we = 0;
+
+ if (init_set)
+ begin
+ init_new = 1;
+ init_we = 1;
+ end
+ else if (init_reg)
+ begin
+ init_new = 0;
+ init_we = 1;
+ end
+ if (next_set)
+ begin
+ next_new = 1;
+ next_we = 1;
+ end
+ else if (next_reg)
+ begin
+ next_new = 0;
+ next_we = 1;
+ end
+ end
+
+
+ //----------------------------------------------------------------
+ // api_logic
+ //
+ // Implementation of the api logic. If cs is enabled will either
+ // try to write to or read from the internal registers.
+ //----------------------------------------------------------------
+ always @*
+ begin : api_logic
+ init_set = 0;
+ next_set = 0;
+ block0_we = 0;
+ block1_we = 0;
+ block2_we = 0;
+ block3_we = 0;
+ block4_we = 0;
+ block5_we = 0;
+ block6_we = 0;
+ block7_we = 0;
+ block8_we = 0;
+ block9_we = 0;
+ block10_we = 0;
+ block11_we = 0;
+ block12_we = 0;
+ block13_we = 0;
+ block14_we = 0;
+ block15_we = 0;
+ tmp_read_data = 32'h00000000;
+ tmp_error = 0;
+
+ if (cs)
+ begin
+ if (we)
+ begin
+ case (address)
+ // Write operations.
+ ADDR_CTRL:
+ begin
+ init_set = write_data[CTRL_INIT_BIT];
+ next_set = write_data[CTRL_NEXT_BIT];
+ end
+
+ ADDR_BLOCK0:
+ begin
+ block0_we = 1;
+ end
+
+ ADDR_BLOCK1:
+ begin
+ block1_we = 1;
+ end
+
+ ADDR_BLOCK2:
+ begin
+ block2_we = 1;
+ end
+
+ ADDR_BLOCK3:
+ begin
+ block3_we = 1;
+ end
+
+ ADDR_BLOCK4:
+ begin
+ block4_we = 1;
+ end
+
+ ADDR_BLOCK5:
+ begin
+ block5_we = 1;
+ end
+
+ ADDR_BLOCK6:
+ begin
+ block6_we = 1;
+ end
+
+ ADDR_BLOCK7:
+ begin
+ block7_we = 1;
+ end
+
+ ADDR_BLOCK8:
+ begin
+ block8_we = 1;
+ end
+
+ ADDR_BLOCK9:
+ begin
+ block9_we = 1;
+ end
+
+ ADDR_BLOCK10:
+ begin
+ block10_we = 1;
+ end
+
+ ADDR_BLOCK11:
+ begin
+ block11_we = 1;
+ end
+
+ ADDR_BLOCK12:
+ begin
+ block12_we = 1;
+ end
+
+ ADDR_BLOCK13:
+ begin
+ block13_we = 1;
+ end
+
+ ADDR_BLOCK14:
+ begin
+ block14_we = 1;
+ end
+
+ ADDR_BLOCK15:
+ begin
+ block15_we = 1;
+ end
+
+ default:
+ begin
+ tmp_error = 1;
+ end
+ endcase // case (address)
+ end // if (we)
+
+ 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_CTRL:
+ begin
+ tmp_read_data = {28'h0000000, 2'b00, next_reg, init_reg};
+ end
+
+ ADDR_STATUS:
+ begin
+ tmp_read_data = {28'h0000000, 2'b00, digest_valid_reg, ready_reg};
+ end
+
+ ADDR_BLOCK0:
+ begin
+ tmp_read_data = block0_reg;
+ end
+
+ ADDR_BLOCK1:
+ begin
+ tmp_read_data = block1_reg;
+ end
+
+ ADDR_BLOCK2:
+ begin
+ tmp_read_data = block2_reg;
+ end
+
+ ADDR_BLOCK3:
+ begin
+ tmp_read_data = block3_reg;
+ end
+
+ ADDR_BLOCK4:
+ begin
+ tmp_read_data = block4_reg;
+ end
+
+ ADDR_BLOCK5:
+ begin
+ tmp_read_data = block5_reg;
+ end
+
+ ADDR_BLOCK6:
+ begin
+ tmp_read_data = block6_reg;
+ end
+
+ ADDR_BLOCK7:
+ begin
+ tmp_read_data = block7_reg;
+ end
+
+ ADDR_BLOCK8:
+ begin
+ tmp_read_data = block8_reg;
+ end
+
+ ADDR_BLOCK9:
+ begin
+ tmp_read_data = block9_reg;
+ end
+
+ ADDR_BLOCK10:
+ begin
+ tmp_read_data = block10_reg;
+ end
+
+ ADDR_BLOCK11:
+ begin
+ tmp_read_data = block11_reg;
+ end
+
+ ADDR_BLOCK12:
+ begin
+ tmp_read_data = block12_reg;
+ end
+
+ ADDR_BLOCK13:
+ begin
+ tmp_read_data = block13_reg;
+ end
+
+ ADDR_BLOCK14:
+ begin
+ tmp_read_data = block14_reg;
+ end
+
+ ADDR_BLOCK15:
+ begin
+ tmp_read_data = block15_reg;
+ end
+
+ ADDR_DIGEST0:
+ begin
+ tmp_read_data = digest_reg[255 : 224];
+ end
+
+ ADDR_DIGEST1:
+ begin
+ tmp_read_data = digest_reg[223 : 192];
+ end
+
+ ADDR_DIGEST2:
+ begin
+ tmp_read_data = digest_reg[191 : 160];
+ end
+
+ ADDR_DIGEST3:
+ begin
+ tmp_read_data = digest_reg[159 : 128];
+ end
+
+ ADDR_DIGEST4:
+ begin
+ tmp_read_data = digest_reg[127 : 96];
+ end
+
+ ADDR_DIGEST5:
+ begin
+ tmp_read_data = digest_reg[95 : 64];
+ end
+
+ ADDR_DIGEST6:
+ begin
+ tmp_read_data = digest_reg[63 : 32];
+ end
+
+ ADDR_DIGEST7:
+ begin
+ tmp_read_data = digest_reg[31 : 0];
+ end
+
+ default:
+ begin
+ tmp_error = 1;
+ end
+ endcase // case (address)
+ end
+ end
+ end // addr_decoder
endmodule // sha256
+
+//======================================================================
+// EOF sha256.v
+//======================================================================