aboutsummaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/rtl/aes_decipher_block.v104
-rw-r--r--src/tb/tb_aes_decipher_block.v5
2 files changed, 29 insertions, 80 deletions
diff --git a/src/rtl/aes_decipher_block.v b/src/rtl/aes_decipher_block.v
index 82bdffb..c2304d6 100644
--- a/src/rtl/aes_decipher_block.v
+++ b/src/rtl/aes_decipher_block.v
@@ -192,12 +192,6 @@ module aes_decipher_block(
//----------------------------------------------------------------
// Registers including update variables and write enable.
//----------------------------------------------------------------
- reg [1 : 0] sword_ctr_reg;
- reg [1 : 0] sword_ctr_new;
- reg sword_ctr_we;
- reg sword_ctr_inc;
- reg sword_ctr_rst;
-
reg [3 : 0] round_ctr_reg;
reg [3 : 0] round_ctr_new;
reg round_ctr_we;
@@ -226,15 +220,24 @@ module aes_decipher_block(
//----------------------------------------------------------------
// Wires.
//----------------------------------------------------------------
- reg [31 : 0] tmp_sboxw;
- wire [31 : 0] new_sboxw;
+ reg [31 : 0] sboxw0;
+ reg [31 : 0] sboxw1;
+ reg [31 : 0] sboxw2;
+ reg [31 : 0] sboxw3;
+ wire [31 : 0] new_sboxw0;
+ wire [31 : 0] new_sboxw1;
+ wire [31 : 0] new_sboxw2;
+ wire [31 : 0] new_sboxw3;
reg [2 : 0] update_type;
//----------------------------------------------------------------
- // Instantiations.
+ // Inverse S-boxes.
//----------------------------------------------------------------
- aes_inv_sbox inv_sbox_inst(.sword(tmp_sboxw), .new_sword(new_sboxw));
+ aes_inv_sbox inv_sbox_inst0(.sword(sboxw0), .new_sword(new_sboxw0));
+ aes_inv_sbox inv_sbox_inst1(.sword(sboxw1), .new_sword(new_sboxw1));
+ aes_inv_sbox inv_sbox_inst2(.sword(sboxw2), .new_sword(new_sboxw2));
+ aes_inv_sbox inv_sbox_inst3(.sword(sboxw3), .new_sword(new_sboxw3));
//----------------------------------------------------------------
@@ -260,7 +263,6 @@ module aes_decipher_block(
block_w1_reg <= 32'h0;
block_w2_reg <= 32'h0;
block_w3_reg <= 32'h0;
- sword_ctr_reg <= 2'h0;
round_ctr_reg <= 4'h0;
ready_reg <= 1'b1;
dec_ctrl_reg <= CTRL_IDLE;
@@ -279,9 +281,6 @@ module aes_decipher_block(
if (block_w3_we)
block_w3_reg <= block_new[031 : 000];
- if (sword_ctr_we)
- sword_ctr_reg <= sword_ctr_new;
-
if (round_ctr_we)
round_ctr_reg <= round_ctr_new;
@@ -308,13 +307,17 @@ module aes_decipher_block(
inv_mixcolumns_block = 128'h0;
addkey_block = 128'h0;
block_new = 128'h0;
- tmp_sboxw = 32'h0;
block_w0_we = 1'b0;
block_w1_we = 1'b0;
block_w2_we = 1'b0;
block_w3_we = 1'b0;
- old_block = {block_w0_reg, block_w1_reg, block_w2_reg, block_w3_reg};
+ sboxw0 = block_w0_reg;
+ sboxw1 = block_w1_reg;
+ sboxw2 = block_w2_reg;
+ sboxw3 = block_w3_reg;
+
+ old_block = {block_w0_reg, block_w1_reg, block_w2_reg, block_w3_reg};
// Update based on update type.
case (update_type)
@@ -333,33 +336,11 @@ module aes_decipher_block(
SBOX_UPDATE:
begin
- block_new = {new_sboxw, new_sboxw, new_sboxw, new_sboxw};
-
- case (sword_ctr_reg)
- 2'h0:
- begin
- tmp_sboxw = block_w0_reg;
- block_w0_we = 1'b1;
- end
-
- 2'h1:
- begin
- tmp_sboxw = block_w1_reg;
- block_w1_we = 1'b1;
- end
-
- 2'h2:
- begin
- tmp_sboxw = block_w2_reg;
- block_w2_we = 1'b1;
- end
-
- 2'h3:
- begin
- tmp_sboxw = block_w3_reg;
- block_w3_we = 1'b1;
- end
- endcase // case (sbox_mux_ctrl_reg)
+ block_new = {new_sboxw0, new_sboxw1, new_sboxw2, new_sboxw3};
+ block_w0_we = 1'b1;
+ block_w1_we = 1'b1;
+ block_w2_we = 1'b1;
+ block_w3_we = 1'b1;
end
MAIN_UPDATE:
@@ -391,29 +372,6 @@ module aes_decipher_block(
//----------------------------------------------------------------
- // sword_ctr
- //
- // The subbytes word counter with reset and increase logic.
- //----------------------------------------------------------------
- always @*
- begin : sword_ctr
- sword_ctr_new = 2'h0;
- sword_ctr_we = 1'b0;
-
- if (sword_ctr_rst)
- begin
- sword_ctr_new = 2'h0;
- sword_ctr_we = 1'b1;
- end
- else if (sword_ctr_inc)
- begin
- sword_ctr_new = sword_ctr_reg + 1'b1;
- sword_ctr_we = 1'b1;
- end
- end // sword_ctr
-
-
- //----------------------------------------------------------------
// round_ctr
//
// The round counter with reset and increase logic.
@@ -450,8 +408,6 @@ module aes_decipher_block(
//----------------------------------------------------------------
always @*
begin: decipher_ctrl
- sword_ctr_inc = 1'b0;
- sword_ctr_rst = 1'b0;
round_ctr_dec = 1'b0;
round_ctr_set = 1'b0;
ready_new = 1'b0;
@@ -475,7 +431,6 @@ module aes_decipher_block(
CTRL_INIT:
begin
- sword_ctr_rst = 1'b1;
update_type = INIT_UPDATE;
dec_ctrl_new = CTRL_SBOX;
dec_ctrl_we = 1'b1;
@@ -483,19 +438,14 @@ module aes_decipher_block(
CTRL_SBOX:
begin
- sword_ctr_inc = 1'b1;
update_type = SBOX_UPDATE;
- if (sword_ctr_reg == 2'h3)
- begin
- round_ctr_dec = 1'b1;
- dec_ctrl_new = CTRL_MAIN;
- dec_ctrl_we = 1'b1;
- end
+ round_ctr_dec = 1'b1;
+ dec_ctrl_new = CTRL_MAIN;
+ dec_ctrl_we = 1'b1;
end
CTRL_MAIN:
begin
- sword_ctr_rst = 1'b1;
if (round_ctr_reg > 0)
begin
update_type = MAIN_UPDATE;
diff --git a/src/tb/tb_aes_decipher_block.v b/src/tb/tb_aes_decipher_block.v
index ec228c0..0475cf5 100644
--- a/src/tb/tb_aes_decipher_block.v
+++ b/src/tb/tb_aes_decipher_block.v
@@ -152,13 +152,12 @@ module tb_aes_decipher_block();
$display("Control states");
$display("round = 0x%01x", dut.round);
- $display("dec_ctrl = 0x%01x, update_type = 0x%01x, sword_ctr = 0x%01x, round_ctr = 0x%01x",
- dut.dec_ctrl_reg, dut.update_type, dut.sword_ctr_reg, dut.round_ctr_reg);
+ $display("dec_ctrl = 0x%01x, update_type = 0x%01x, round_ctr = 0x%01x",
+ dut.dec_ctrl_reg, dut.update_type, dut.round_ctr_reg);
$display("");
$display("Internal data values");
$display("round_key = 0x%016x", dut.round_key);
- $display("sboxw = 0x%08x, new_sboxw = 0x%08x", dut.tmp_sboxw, dut.new_sboxw);
$display("block_w0_reg = 0x%08x, block_w1_reg = 0x%08x, block_w2_reg = 0x%08x, block_w3_reg = 0x%08x",
dut.block_w0_reg, dut.block_w1_reg, dut.block_w2_reg, dut.block_w3_reg);
$display("");
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 01:52:15 +0000