added all required functionality for correct execution (except for read buffer aware reads)

src/fifo_buffer/fifo_buffer.vhd

@@ -20,7 +20,8 @@ entity fifo_buffer is
     valid_in : in std_logic;
     valid_out : out std_logic;
     data_in : in std_logic_vector(data_width - 1 downto 0);
-    data_out : out std_logic_vector(data_width - 1 downto 0)
+    data_out : out std_logic_vector(data_width - 1 downto 0);
+    used_slots  : out integer range 0 to buffer_size
   );
 end entity fifo_buffer;
 
@@ -34,26 +35,11 @@ architecture rtl of fifo_buffer is
   signal inverted_in_clock : std_logic;
   signal customout       : std_logic_vector(0 downto 0); -- techmap needs customout and it is does not have a default value for some reason
 begin
- 
--- DECLARATION OF NX_SYNCRAM
---entity nx_syncram_be is
---  generic ( abits : integer    := 6;
---            dbits : integer    := 8
---            );
---  port (
---    clk     : in  std_ulogic;
---    address : in  std_logic_vector  (abits -1  downto 0);
---    datain  : in  std_logic_vector  (dbits -1  downto 0);
---    dataout : out std_logic_vector  (dbits -1  downto 0);
---    enable  : in  std_logic_vector  (dbits/8-1 downto 0);
---    write   : in  std_logic_vector  (dbits/8-1 downto 0)
---    );
---end;
 
   techmap_ram_inst : entity techmap.syncram_2p
   generic map(tech => tech, 
               abits => address_bits, 
-              dbits => fifo_width,
+              dbits => data_width,
               sepclk => 1
              )
   port map(
@@ -73,6 +59,11 @@ begin
 comb_proc: process(write_pointer, read_pointer, buffer_full, valid_in, rst)
   variable write_pointer_inc : unsigned(address_bits - 1 downto 0);
 begin
+  if write_pointer >= read_pointer then
+    used_slots <= to_integer(unsigned(write_pointer) - unsigned(read_pointer));
+  else
+    used_slots <= buffer_size - to_integer(unsigned(read_pointer)) + to_integer(unsigned(write_pointer));
+  end if;
   ready_out <= not buffer_full;
   write_signal <= (valid_in and not buffer_full) or rst;
   write_pointer_inc := unsigned(write_pointer) + 1;
@@ -95,11 +86,13 @@ begin
       read_pointer <= (others => '0');
       write_pointer <= (others => '0');
   else
-    if rising_edge(in_clk) and valid_in = '1' and buffer_full = '0' then
+    if rising_edge(in_clk) then
-      write_pointer <= std_logic_vector(unsigned(write_pointer) + 1);
+      if valid_in = '1' and buffer_full = '0'then
+        write_pointer <= std_logic_vector(unsigned(write_pointer) + 1);
+      end if;
     end if;
-    if falling_edge(out_clk) then
+    if rising_edge(out_clk) then
-       if ready_in = '1' and buffer_empty = '0' then
+      if ready_in = '1' and buffer_empty = '0' then
         read_pointer <= std_logic_vector(unsigned(read_pointer) + 1);
         valid_out <= '1';
       else
@@ -110,3 +103,118 @@ begin
 end process seq_proc;
 
 end architecture rtl;
+
+
+
+--library IEEE;
+--use IEEE.std_logic_1164.all;
+--use IEEE.MATH_REAL.all;
+--use ieee.numeric_std.all;
+--library gan_ganimede;
+--use gan_ganimede.io_types.all;
+--library techmap;
+--use techmap.gencomp.all;
+--
+--entity fifo_buffer is
+--  generic (
+--    buffer_size : natural := 64;
+--    tech : integer := 0;
+--    data_width : natural := 8
+--  );
+--  port (
+--    rst, in_clk, out_clk : in std_logic;
+--    ready_in : in std_logic;
+--    ready_out : out std_logic;
+--    valid_in : in std_logic;
+--    valid_out : out std_logic;
+--    data_in : in std_logic_vector(data_width - 1 downto 0);
+--    data_out : out std_logic_vector(data_width - 1 downto 0)
+--  );
+--end entity fifo_buffer;
+--
+--architecture rtl of fifo_buffer is
+--  constant address_bits  : natural := integer(ceil(log2(real(buffer_size))));
+--  signal read_pointer : std_logic_vector(address_bits - 1 downto 0);
+--  signal write_pointer  : std_logic_vector(address_bits - 1 downto 0);
+--  signal write_signal    : std_logic;
+--  signal buffer_full     : std_logic;
+--  signal buffer_empty    : std_logic;
+--  signal inverted_in_clock : std_logic;
+--  signal customout       : std_logic_vector(0 downto 0); -- techmap needs customout and it is does not have a default value for some reason
+--begin
+-- 
+---- DECLARATION OF NX_SYNCRAM
+----entity nx_syncram_be is
+----  generic ( abits : integer    := 6;
+----            dbits : integer    := 8
+----            );
+----  port (
+----    clk     : in  std_ulogic;
+----    address : in  std_logic_vector  (abits -1  downto 0);
+----    datain  : in  std_logic_vector  (dbits -1  downto 0);
+----    dataout : out std_logic_vector  (dbits -1  downto 0);
+----    enable  : in  std_logic_vector  (dbits/8-1 downto 0);
+----    write   : in  std_logic_vector  (dbits/8-1 downto 0)
+----    );
+----end;
+--
+--  techmap_ram_inst : entity techmap.syncram_2p
+--  generic map(tech => tech, 
+--              abits => address_bits, 
+--              dbits => data_width,
+--              sepclk => 1
+--             )
+--  port map(
+--    rclk     => out_clk,
+--    renable  => '1',
+--    raddress => read_pointer,
+--    dataout  => data_out,
+--    wclk     => inverted_in_clock,
+--    write    => write_signal,
+--    waddress => write_pointer,
+--    datain   => data_in,
+--    customclk => in_clk, --NOTE: No clue what this does but it has to be set to something
+--    customout => customout
+--    );
+--  
+--  inverted_in_clock <= not in_clk;
+--comb_proc: process(write_pointer, read_pointer, buffer_full, valid_in, rst)
+--  variable write_pointer_inc : unsigned(address_bits - 1 downto 0);
+--begin
+--  ready_out <= not buffer_full;
+--  write_signal <= (valid_in and not buffer_full) or rst;
+--  write_pointer_inc := unsigned(write_pointer) + 1;
+--  customout <= "0";
+--  if write_pointer_inc = unsigned(read_pointer) then
+--    buffer_full <= '1';
+--  else
+--    buffer_full <= '0';
+--  end if;
+--  if write_pointer = read_pointer then
+--    buffer_empty <= '1';
+--  else
+--    buffer_empty <= '0';
+--  end if;
+--end process comb_proc;
+--
+--seq_proc: process(rst, in_clk, out_clk, buffer_full, valid_in, ready_in, buffer_empty, write_pointer, read_pointer)
+--begin
+--  if rst = '1' then
+--      read_pointer <= (others => '0');
+--      write_pointer <= (others => '0');
+--  else
+--    if rising_edge(in_clk) and valid_in = '1' and buffer_full = '0' then
+--      write_pointer <= std_logic_vector(unsigned(write_pointer) + 1);
+--    end if;
+--    if falling_edge(out_clk) then
+--       if ready_in = '1' and buffer_empty = '0' then
+--        read_pointer <= std_logic_vector(unsigned(read_pointer) + 1);
+--        valid_out <= '1';
+--      else
+--        valid_out <= '0';
+--      end if;
+--    end if;
+--  end if;
+--end process seq_proc;
+--
+--end architecture rtl;

src/fifo_buffer/fifo_deserializer.vhd

@@ -0,0 +1,74 @@
+library IEEE;
+use IEEE.std_logic_1164.all;
+use IEEE.MATH_REAL.all;
+use ieee.numeric_std.all;
+
+entity fifo_deserializer is
+  generic (
+    output_width : natural := 8;
+    input_width  : natural := 8;
+    endianess    : integer := 0  -- 0: little endian, 1: big endian
+  );
+  port (
+    rst, clk : in std_logic;
+    ready_in : in std_logic;
+    ready_out : out std_logic;
+    valid_in : in std_logic;
+    valid_out : out std_logic;
+    data_in : in std_logic_vector(input_width - 1 downto 0);
+    data_out : out std_logic_vector(output_width - 1 downto 0)
+  );
+end entity fifo_deserializer;
+
+architecture rtl of fifo_deserializer is
+
+constant out_over_in : natural := output_width / input_width - 1;
+type state_t is record
+  count : integer;
+  data : std_logic_vector(output_width - 1 downto 0);
+  full_word : std_logic;
+  prev_ready : std_logic;
+end record state_t;
+signal st : state_t;
+begin
+
+comb_proc: process(rst,clk,valid_in,ready_in,data_in,st)
+begin
+  if st.full_word = '1' and ready_in = '1' then
+    valid_out <= '1';
+  else 
+    valid_out <= '0';
+  end if;
+  ready_out <= ready_in;
+  data_out <= st.data;
+end process comb_proc; 
+
+seq_proc: process(clk, rst)
+begin
+  if rst = '1' then
+    st.count <= 0;
+    st.data <= (others => '0');
+    st.full_word <= '0';
+    st.prev_ready <= '0';
+  elsif (rising_edge(clk)) then
+    st.prev_ready <= ready_in;
+    if valid_in = '1' and st.prev_ready = '1' then
+      if endianess = 0 then
+        st.data((out_over_in + 1 - st.count) * input_width  - 1 downto (out_over_in - st.count) * input_width) <= data_in;
+      else
+        st.data((st.count + 1) * input_width - 1 downto st.count * input_width) <= data_in;
+      end if;
+    end if;
+    if st.full_word = '1' and ready_in = '1' then
+      st.full_word <= '0';
+    end if;
+    if st.count = out_over_in and valid_in = '1' then
+      st.full_word <= '1';
+      st.count <= 0;
+    elsif valid_in = '1' then
+      st.count <= st.count + 1;
+    end if;
+  end if;
+end process seq_proc;
+
+end architecture rtl;

src/fifo_buffer/fifo_serializer.vhd

@@ -0,0 +1,76 @@
+library IEEE;
+use IEEE.std_logic_1164.all;
+use IEEE.MATH_REAL.all;
+use ieee.numeric_std.all;
+
+entity fifo_serializer is
+  generic (
+    output_width : natural := 8;
+    input_width  : natural := 8;
+    endianess    : integer := 0 -- 0: little endian, 1: big endian
+  );
+  port (
+    rst, clk : in std_logic;
+    ready_in : in std_logic;
+    ready_out : out std_logic;
+    valid_in : in std_logic;
+    valid_out : out std_logic;
+    data_in : in std_logic_vector(input_width - 1 downto 0);
+    data_out : out std_logic_vector(output_width - 1 downto 0)
+  );
+end entity fifo_serializer;
+
+architecture rtl of fifo_serializer is
+
+constant in_over_out : natural := input_width / output_width - 1;
+type state_t is record
+  count : integer;
+  valid : std_logic;
+  data : std_logic_vector(input_width - 1 downto 0);
+end record state_t;
+signal st : state_t;
+begin
+
+comb_proc: process(rst,clk,valid_in,ready_in,data_in,st)
+begin
+  if st.valid = '0' and valid_in = '0' then
+    ready_out <= '1';
+  else 
+    ready_out <= '0';
+  end if;
+  valid_out <= st.valid;
+  if st.count <= in_over_out and st.valid = '1' then
+    if endianess = 0 then
+      data_out <= st.data((input_width - st.count * output_width) - 1 downto input_width - (st.count + 1) * output_width);
+    else
+      data_out <= st.data((st.count + 1) * output_width - 1 downto st.count * output_width);
+    end if;
+  else
+    data_out <= (others => '0');
+  end if;
+end process comb_proc; 
+
+seq_proc: process(clk, rst)
+begin
+  if rst = '1' then
+    st.count <= 0;
+    st.valid <= '0';
+    st.data <= (others => '0');
+  elsif (rising_edge(clk)) then
+    if valid_in = '1' and st.count = 0 then
+      st.valid <= '1';
+      st.data <= data_in;
+    elsif valid_in = '1' and st.count = in_over_out and ready_in = '1' then
+      st.count <= 0;
+      st.valid <= '1';
+      st.data <= data_in;
+    elsif st.count = in_over_out and ready_in = '1' then
+      st.valid <= '0';
+      st.count <= 0;
+    elsif ready_in = '1' and st.valid = '1' then
+      st.count <= st.count + 1;
+    end if;
+  end if;
+end process seq_proc;
+
+end architecture rtl;

src/ganimede/ganimede.vhd

@@ -30,6 +30,7 @@ architecture rtl of ganimede_toplevel is
   signal socbridge_driver_to_buffer : fifo_interface_t;
   signal buffer_to_socbridge_driver : fifo_interface_t;
   signal socbridge_clk : std_logic;
+  signal used_slots : integer;
 
   --signal gan_socbridge_WE_in : std_logic;
   --signal gan_socbridge_WE_out : std_logic;
@@ -52,7 +53,8 @@ begin
       ext_to_socbridge_driver        => ext_to_ganimede.socbridge,
       socbridge_driver_to_ext        => ganimede_to_ext.socbridge,
       ip_to_socbridge_driver         => buffer_to_socbridge_driver,
-      socbridge_driver_to_ip         => socbridge_driver_to_buffer
+      socbridge_driver_to_ip         => socbridge_driver_to_buffer,
+      used_slots => used_slots
     );
 
   controller_inst: entity gan_controller.control_unit
@@ -77,7 +79,7 @@ begin
 
   fifo_buffer_to_ip_inst : entity gan_buffer.fifo_buffer
     generic map (
-      buffer_size => 1024
+      buffer_size => 2*1024
     )
     port map(
       in_clk => socbridge_clk,
@@ -93,7 +95,7 @@ begin
 
   fifo_buffer_from_ip_inst : entity gan_buffer.fifo_buffer
     generic map (
-      buffer_size => 1024
+      buffer_size => 2*1024
     )
     port map(
       in_clk => clk, 
@@ -104,7 +106,8 @@ begin
       valid_in => ip_to_ganimede.socbridge.valid,
       valid_out => buffer_to_socbridge_driver.valid,
       data_in => ip_to_ganimede.socbridge.data,
-      data_out => buffer_to_socbridge_driver.data
+      data_out => buffer_to_socbridge_driver.data,
+      used_slots => used_slots
     );
     
   --- LATER WE ADD OPTIMIZATIONS HERE ---

src/manager/management_unit.vhd

@@ -45,7 +45,7 @@ begin
 read_address  <= manager_state.memory(0);
 write_address <= manager_state.memory(1);
 
-comb_proc: process(controller_to_manager, socbridge_driver_to_manager,manager_state)
+comb_proc: process(controller_to_manager, socbridge_driver_to_manager,manager_state, cmd)
   variable local_word_address : natural;
 begin
   local_word_address := to_integer(shift_right(unsigned(socbridge_driver_to_manager.address), address_shift)) mod mem_words;
@@ -91,7 +91,7 @@ begin
       elsif pack(write_address) /= empty_word and controller_to_manager.ready = '1' and controller_to_manager.done = '0'then
         manager_to_controller.address <= write_address.address & "0000000000";
         manager_to_controller.driver_id <= "1"; -- Only supports one driver at present
-        manager_to_controller.seq_mem_access_count <= 2**to_integer(unsigned(read_address.size)) * 2**10;
+        manager_to_controller.seq_mem_access_count <= 2**to_integer(unsigned(write_address.size)) * 2**10;
         cmd <= "01";
       else
       -- No instruction present in memory, all zeroes to control unit

src/socbridge/socbridge_driver.vhd

@@ -11,7 +11,7 @@ use gan_manager.management_types.all;
 
 entity socbridge_driver is
   generic(
-    MAX_PKT_SIZE : integer range 1 to 128 := 32
+    MAX_PKT_SIZE : integer range 1 to 128 := 8
          );
   port(
     clk                            : in std_logic;
@@ -24,7 +24,8 @@ entity socbridge_driver is
     ext_to_socbridge_driver        : in ext_to_socbridge_driver_t;
     socbridge_driver_to_ext        : out socbridge_driver_to_ext_t;
     ip_to_socbridge_driver         : in ip_to_socbridge_driver_t;
-    socbridge_driver_to_ip         : out socbridge_driver_to_ip_t
+    socbridge_driver_to_ip         : out socbridge_driver_to_ip_t;
+    used_slots                     : in integer
   );
 end entity socbridge_driver;
 
@@ -55,7 +56,7 @@ begin
   comb_proc: process(ext_to_socbridge_driver, ip_to_socbridge_driver, 
                      st, controller_to_socbridge_driver, trans_st,
                      tx_sent_response, rx_received_response,
-                     valid_out)
+                     valid_out, used_slots)
     variable curr_response_bits : std_logic_vector(4 downto 0);
     variable local_next_rx_transaction : transaction_t;
     variable local_next_tx_transaction : transaction_t;
@@ -226,10 +227,17 @@ begin
         else 
           local_next_data_out := get_header_bits(st.curr_tx_transaction, st.curr_rx_transaction) & get_size_bits(st.tx_data_size);
         end if;
-      when TX_W_BODY =>
+        if st.curr_tx_transaction = WRITE then
-        if st.tx_stage > 0 then
           socbridge_driver_to_ip.ready <= '1';
+        end if;
+      when TX_W_BODY =>
+        if st.tx_stage > 1 then
+          socbridge_driver_to_ip.ready <= '1';
+        end if;
+        if st.tx_stage > 0 and ip_to_socbridge_driver.valid = '1' then
           local_next_data_out := ip_to_socbridge_driver.data;
+        else 
+          local_next_data_out := (others => '0');
         end if;
       when TX_R_BODY =>
         if st.tx_stage > 0 then
@@ -244,6 +252,9 @@ begin
         local_next_data_out := st.curr_tx_addr(15 downto 8);
       when ADDR4 =>
         local_next_data_out := st.curr_tx_addr(7 downto 0);
+        if st.curr_tx_transaction = WRITE_ADD then
+          socbridge_driver_to_ip.ready <= '1';
+        end if;
     end case;
     --- ### RX_STATE BASED OUTPUT ### ---
     socbridge_driver_to_manager.valid <= '0';
@@ -294,7 +305,7 @@ begin
       when AWAIT =>
         if trans_st.curr_inst.seq_mem_access_count <= 0 and st.curr_tx_state = IDLE then
           trans_next_state <= IDLE;
-        elsif st.curr_tx_state = IDLE then
+        elsif st.curr_tx_state = IDLE and not (trans_st.curr_inst.instruction = WRITE and used_slots < MAX_PKT_SIZE)then
           trans_next_state <= SEND;
         else 
           trans_next_state <= AWAIT;
@@ -479,8 +490,12 @@ begin
           end if;
           trans_st.is_first_word <= '1';
         when SEND =>
+          if trans_st.curr_inst.seq_mem_access_count mod 256 = 0 then
+            trans_st.is_first_word <= '1';
+          end if;
         when SEND_ACCEPTED => 
           trans_st.curr_inst.seq_mem_access_count <= trans_st.curr_inst.seq_mem_access_count - MAX_PKT_SIZE;
+          trans_st.curr_inst.address <= std_logic_vector(unsigned(trans_st.curr_inst.address) + MAX_PKT_SIZE);
         when AWAIT =>
           if trans_st.curr_inst.seq_mem_access_count <= 0 and st.curr_tx_state = IDLE then
             trans_st.curr_inst.request <= '0';
@@ -489,6 +504,9 @@ begin
             trans_st.curr_inst.instruction <= NO_OP;
           end if;
           trans_st.is_first_word <= '0';
+          if trans_st.curr_inst.seq_mem_access_count mod 256 = 0 then
+            trans_st.is_first_word <= '1';
+          end if;
         when others =>
       end case;
     end if;