[aes/rtl] Use ternaries instead of `if/else` + `unique case`
Signed-off-by: Pirmin Vogel <vogelpi@lowrisc.org>
diff --git a/hw/ip/aes/rtl/aes_control.sv b/hw/ip/aes/rtl/aes_control.sv
index 48d569f..2763db6 100644
--- a/hw/ip/aes/rtl/aes_control.sv
+++ b/hw/ip/aes/rtl/aes_control.sv
@@ -4,9 +4,7 @@
//
// AES control
-module aes_control #(
- parameter bit AES192Enable = 1
-) (
+module aes_control (
input logic clk_i,
input logic rst_ni,
@@ -204,35 +202,12 @@
add_rk_sel_o = ADD_RK_INIT;
// Select key words for initial add_round_key
- if (dec_key_gen_q) begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end else begin
- unique case (key_len_i)
- AES_128: key_words_sel_o = KEY_WORDS_0123;
-
- AES_192: begin
- if (AES192Enable) begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_0123;
- AES_DEC: key_words_sel_o = KEY_WORDS_2345;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end else begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end
- end
-
- AES_256: begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_0123;
- AES_DEC: key_words_sel_o = KEY_WORDS_4567;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
-
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
+ key_words_sel_o = dec_key_gen_q ? KEY_WORDS_ZERO :
+ (key_len_i == AES_128) ? KEY_WORDS_0123 :
+ (key_len_i == AES_192 && mode_i == AES_ENC) ? KEY_WORDS_0123 :
+ (key_len_i == AES_192 && mode_i == AES_DEC) ? KEY_WORDS_2345 :
+ (key_len_i == AES_256 && mode_i == AES_ENC) ? KEY_WORDS_0123 :
+ (key_len_i == AES_256 && mode_i == AES_DEC) ? KEY_WORDS_4567 : KEY_WORDS_ZERO;
// Make key expand advance - AES-256 has two round keys available right from beginning
if (key_len_i != AES_256) begin
@@ -252,35 +227,12 @@
state_we_o = ~dec_key_gen_q;
// Select key words for add_round_key
- if (dec_key_gen_q) begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end else begin
- unique case (key_len_i)
- AES_128: key_words_sel_o = KEY_WORDS_0123;
-
- AES_192: begin
- if (AES192Enable) begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_2345;
- AES_DEC: key_words_sel_o = KEY_WORDS_0123;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end else begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end
- end
-
- AES_256: begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_4567;
- AES_DEC: key_words_sel_o = KEY_WORDS_0123;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
-
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
+ key_words_sel_o = dec_key_gen_q ? KEY_WORDS_ZERO :
+ (key_len_i == AES_128) ? KEY_WORDS_0123 :
+ (key_len_i == AES_192 && mode_i == AES_ENC) ? KEY_WORDS_2345 :
+ (key_len_i == AES_192 && mode_i == AES_DEC) ? KEY_WORDS_0123 :
+ (key_len_i == AES_256 && mode_i == AES_ENC) ? KEY_WORDS_4567 :
+ (key_len_i == AES_256 && mode_i == AES_DEC) ? KEY_WORDS_0123 : KEY_WORDS_ZERO;
// Make key expand advance
key_expand_step_o = 1'b1;
@@ -309,35 +261,12 @@
// Final round
// Select key words for add_round_key
- if (dec_key_gen_q) begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end else begin
- unique case (key_len_i)
- AES_128: key_words_sel_o = KEY_WORDS_0123;
-
- AES_192: begin
- if (AES192Enable) begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_2345;
- AES_DEC: key_words_sel_o = KEY_WORDS_0123;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end else begin
- key_words_sel_o = KEY_WORDS_ZERO;
- end
- end
-
- AES_256: begin
- unique case (mode_i)
- AES_ENC: key_words_sel_o = KEY_WORDS_4567;
- AES_DEC: key_words_sel_o = KEY_WORDS_0123;
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
-
- default: key_words_sel_o = KEY_WORDS_ZERO;
- endcase
- end
+ key_words_sel_o = dec_key_gen_q ? KEY_WORDS_ZERO :
+ (key_len_i == AES_128) ? KEY_WORDS_0123 :
+ (key_len_i == AES_192 && mode_i == AES_ENC) ? KEY_WORDS_2345 :
+ (key_len_i == AES_192 && mode_i == AES_DEC) ? KEY_WORDS_0123 :
+ (key_len_i == AES_256 && mode_i == AES_ENC) ? KEY_WORDS_4567 :
+ (key_len_i == AES_256 && mode_i == AES_DEC) ? KEY_WORDS_0123 : KEY_WORDS_ZERO;
// Skip mix_columns
add_rk_sel_o = ADD_RK_FINAL;
diff --git a/hw/ip/aes/rtl/aes_core.sv b/hw/ip/aes/rtl/aes_core.sv
index 148e7a0..c66e625 100644
--- a/hw/ip/aes/rtl/aes_core.sv
+++ b/hw/ip/aes/rtl/aes_core.sv
@@ -283,9 +283,7 @@
/////////////
// Control
- aes_control #(
- .AES192Enable (AES192Enable)
- ) aes_control (
+ aes_control aes_control (
.clk_i ( clk_i ),
.rst_ni ( rst_ni ),
