Adds priority encoders and pipeline-based modules

Implements various priority encoder components with combinatorial logic for encoding input vectors to output codes of varying widths. Introduces pipeline-based modules for handling calculation, ROM data fetching, and scheduling operations with AXI-like handshaking interfaces. Facilitates modular and reusable design for priority encoding and data processing tasks.
2025-04-20 03:02:02 +00:00
commit bbe0ff9b9e
4 changed files with 1001 additions and 0 deletions
--- a/libs/PriorityEncoders.vhd
+++ b/libs/PriorityEncoders.vhd
@@ -0,0 +1,345 @@
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (2 to 1 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 1-bit output code.
+entity PriorityEncoder_2 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(1 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(0 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_2;
+
+architecture Combinatoric of PriorityEncoder_2 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(0 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+begin
+    C_Code <= "0" when I_Select(1) = '1' else
+              "1" when I_Select(0) = '1' else
+              "-";
+
+    O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (4 to 2 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 2-bit output code.
+entity PriorityEncoder_4 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(3 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(1 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_4;
+
+architecture Combinatoric of PriorityEncoder_4 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(1 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+begin
+    C_Code <= "00" when I_Select(3) = '1' else
+              "01" when I_Select(2) = '1' else
+              "10" when I_Select(1) = '1' else
+              "11" when I_Select(0) = '1' else
+              "--";
+              
+              O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (8 to 3 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 3-bit output code.
+entity PriorityEncoder_8 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(7 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(2 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_8;
+
+architecture Combinatoric of PriorityEncoder_8 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(2 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+begin
+    C_Code <= "000" when I_Select(7) = '1' else
+              "001" when I_Select(6) = '1' else
+              "010" when I_Select(5) = '1' else
+              "011" when I_Select(4) = '1' else
+              "100" when I_Select(3) = '1' else
+              "101" when I_Select(2) = '1' else
+              "110" when I_Select(1) = '1' else
+              "111" when I_Select(0) = '1' else
+              "---";
+              
+              O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (16 to 4 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 4-bit output code.
+entity PriorityEncoder_16 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(15 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(3 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_16;
+
+architecture Combinatoric of PriorityEncoder_16 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(3 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+begin
+    C_Code <= "0000" when I_Select(15) = '1' else
+              "0001" when I_Select(14) = '1' else
+              "0010" when I_Select(13) = '1' else
+              "0011" when I_Select(12) = '1' else
+              "0100" when I_Select(11) = '1' else
+              "0101" when I_Select(10) = '1' else
+              "0110" when I_Select(9) = '1' else
+              "0111" when I_Select(8) = '1' else
+              "1000" when I_Select(7) = '1' else
+              "1001" when I_Select(6) = '1' else
+              "1010" when I_Select(5) = '1' else
+              "1011" when I_Select(4) = '1' else
+              "1100" when I_Select(3) = '1' else
+              "1101" when I_Select(2) = '1' else
+              "1110" when I_Select(1) = '1' else
+              "1111" when I_Select(0) = '1' else
+              "----";
+              
+              O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (32 to 5 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 5-bit output code.
+entity PriorityEncoder_32 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(31 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(4 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_32;
+
+architecture Combinatoric of PriorityEncoder_32 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(4 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+
+begin
+    C_Code <= "00000" when I_Select(31) = '1' else
+              "00001" when I_Select(30) = '1' else
+              "00010" when I_Select(29) = '1' else
+              "00011" when I_Select(28) = '1' else
+              "00100" when I_Select(27) = '1' else
+              "00101" when I_Select(26) = '1' else
+              "00110" when I_Select(25) = '1' else
+              "00111" when I_Select(24) = '1' else
+              "01000" when I_Select(23) = '1' else
+              "01001" when I_Select(22) = '1' else
+              "01010" when I_Select(21) = '1' else
+              "01011" when I_Select(20) = '1' else
+              "01100" when I_Select(19) = '1' else
+              "01101" when I_Select(18) = '1' else
+              "01110" when I_Select(17) = '1' else
+              "01111" when I_Select(16) = '1' else
+              "10000" when I_Select(15) = '1' else
+              "10001" when I_Select(14) = '1' else
+              "10010" when I_Select(13) = '1' else
+              "10011" when I_Select(12) = '1' else
+              "10100" when I_Select(11) = '1' else
+              "10101" when I_Select(10) = '1' else
+              "10110" when I_Select(9) = '1' else
+              "10111" when I_Select(8) = '1' else
+              "11000" when I_Select(7) = '1' else
+              "11001" when I_Select(6) = '1' else
+              "11010" when I_Select(5) = '1' else
+              "11011" when I_Select(4) = '1' else
+              "11100" when I_Select(3) = '1' else
+              "11101" when I_Select(2) = '1' else
+              "11110" when I_Select(1) = '1' else
+              "11111" when I_Select(0) = '1' else
+              "-----";
+              
+              O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+--@ Priority Encoder (64 to 6 bits)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 6-bit output code.
+entity PriorityEncoder_64 is
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(63 downto 0) := (others => '0');
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(5 downto 0) := (others => '0')
+    );
+end entity PriorityEncoder_64;
+
+architecture Combinatoric of PriorityEncoder_64 is
+    --@ Internal signal to hold the encoded output.
+    signal C_Code : std_logic_vector(5 downto 0);
+
+    --@ Attribute to force the synthesis tool (XST, old Parser) to treat this as a combinatorial signal.
+    attribute PRIORITY_EXTRACT : string;
+    attribute PRIORITY_EXTRACT of C_Code : signal is "force";
+
+begin
+    C_Code <= "000000" when I_Select(63) = '1' else
+              "000001" when I_Select(62) = '1' else
+              "000010" when I_Select(61) = '1' else
+              "000011" when I_Select(60) = '1' else
+              "000100" when I_Select(59) = '1' else
+              "000101" when I_Select(58) = '1' else
+              "000110" when I_Select(57) = '1' else
+              "000111" when I_Select(56) = '1' else
+              "001000" when I_Select(55) = '1' else
+              "001001" when I_Select(54) = '1' else
+              "001010" when I_Select(53) = '1' else
+              "001011" when I_Select(52) = '1' else
+              "001100" when I_Select(51) = '1' else
+              "001101" when I_Select(50) = '1' else
+              "001110" when I_Select(49) = '1' else
+              "001111" when I_Select(48) = '1' else
+              "010000" when I_Select(47) = '1' else
+              "010001" when I_Select(46) = '1' else
+              "010010" when I_Select(45) = '1' else
+              "010011" when I_Select(44) = '1' else
+              "010100" when I_Select(43) = '1' else
+              "010101" when I_Select(42) = '1' else
+              "010110" when I_Select(41) = '1' else
+              "010111" when I_Select(40) = '1' else
+              "011000" when I_Select(39) = '1' else
+              "011001" when I_Select(38) = '1' else
+              "011010" when I_Select(37) = '1' else
+              "011011" when I_Select(36) = '1' else
+              "011100" when I_Select(35) = '1' else
+              "011101" when I_Select(34) = '1' else
+              "011110" when I_Select(33) = '1' else
+              "011111" when I_Select(32) = '1' else
+              "100000" when I_Select(31) = '1' else
+              "100001" when I_Select(30) = '1' else
+              "100010" when I_Select(29) = '1' else
+              "100011" when I_Select(28) = '1' else
+              "100100" when I_Select(27) = '1' else
+              "100101" when I_Select(26) = '1' else
+              "100110" when I_Select(25) = '1' else
+              "100111" when I_Select(24) = '1' else
+              "101000" when I_Select(23) = '1' else
+              "101001" when I_Select(22) = '1' else
+              "101010" when I_Select(21) = '1' else
+              "101011" when I_Select(20) = '1' else
+              "101100" when I_Select(19) = '1' else
+              "101101" when I_Select(18) = '1' else
+              "101110" when I_Select(17) = '1' else
+              "101111" when I_Select(16) = '1' else
+              "110000" when I_Select(15) = '1' else
+              "110001" when I_Select(14) = '1' else
+              "110010" when I_Select(13) = '1' else
+              "110011" when I_Select(12) = '1' else
+              "110100" when I_Select(11) = '1' else
+              "110101" when I_Select(10) = '1' else
+              "110110" when I_Select(9) = '1' else
+              "110111" when I_Select(8) = '1' else
+              "111000" when I_Select(7) = '1' else
+              "111001" when I_Select(6) = '1' else
+              "111010" when I_Select(5) = '1' else
+              "111011" when I_Select(4) = '1' else
+              "111100" when I_Select(3) = '1' else
+              "111101" when I_Select(2) = '1' else
+              "111110" when I_Select(1) = '1' else
+              "111111" when I_Select(0) = '1' else
+              "------";
+              
+              O_Code <= C_Code;
+end architecture;
+
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.numeric_std.all;
+use ieee.math_real.all;
+
+--@ Priority Encoder (Generic)
+--@ This is a combinatorial priority encoder that encodes the highest priority
+--@ bit in the input vector to a 6-bit output code.
+entity PriorityEncoder_G is
+    generic (
+        --@ Code width with minimum 2 bits and maximum 6 bits.
+        G_CodeWidth : integer := 6
+    );
+    port (
+        --@ Input vector to be encoded.  
+        --@ The least significant bit has the highest priority.
+        I_Select : in std_logic_vector(2 ** G_CodeWidth - 1 downto 0);
+        --@ Output code.
+        --@ The output code is the index of the highest priority bit in the input vector.
+        O_Code : out std_logic_vector(G_CodeWidth - 1 downto 0)
+    );
+end entity PriorityEncoder_G;
+
+architecture Combinatoric of PriorityEncoder_G is
+    signal C_Select : std_logic_vector(63 downto 0) := (others => '-');
+    signal C_Code : std_logic_vector(5 downto 0) := (others => '-');
+begin
+
+    entity_inst : entity work.PriorityEncoder_64
+        port map(
+            I_Select => C_Select,
+            O_Code => C_Code
+        );
+
+    C_Select(G_CodeWidth * 2 - 1 downto 0) <= I_Select;
+    O_Code <= C_Code(G_CodeWidth - 1 downto 0);
+end architecture;