Merge pull request #51 from antonblanchard/writeback-fix

Some writeback updates

writeback.vhdl

@@ -6,106 +6,106 @@ library work;
 use work.common.all;
 
 entity writeback is
-	port (
+    port (
-		clk          : in std_ulogic;
+        clk          : in std_ulogic;
 
-		e_in         : in Execute2ToWritebackType;
+        e_in         : in Execute2ToWritebackType;
-		l_in         : in Loadstore2ToWritebackType;
+        l_in         : in Loadstore2ToWritebackType;
-		m_in         : in MultiplyToWritebackType;
+        m_in         : in MultiplyToWritebackType;
 
-		w_out        : out WritebackToRegisterFileType;
+        w_out        : out WritebackToRegisterFileType;
-		c_out        : out WritebackToCrFileType;
+        c_out        : out WritebackToCrFileType;
 
-		complete_out : out std_ulogic
+        complete_out : out std_ulogic
-	);
+        );
 end entity writeback;
 
 architecture behaviour of writeback is
-	type reg_internal_type is record
+    type reg_internal_type is record
-		complete : std_ulogic;
+        complete : std_ulogic;
-	end record;
+    end record;
-	type reg_type is record
+    type reg_type is record
-		w : WritebackToRegisterFileType;
+        w : WritebackToRegisterFileType;
-		c : WritebackToCrFileType;
+        c : WritebackToCrFileType;
-	end record;
+    end record;
-	signal r, rin : reg_type;
+    signal r, rin         : reg_type;
-	signal r_int, rin_int : reg_internal_type;
+    signal r_int, rin_int : reg_internal_type;
 begin
-	writeback_0: process(clk)
+    writeback_0: process(clk)
-	begin
+    begin
-		if rising_edge(clk) then
+        if rising_edge(clk) then
-			r <= rin;
+            r <= rin;
-			r_int <= rin_int;
+            r_int <= rin_int;
-		end if;
+        end if;
-	end process;
+    end process;
-
+
-	writeback_1: process(all)
+    writeback_1: process(all)
-		variable x: std_ulogic_vector(0 downto 0);
+        variable x     : std_ulogic_vector(0 downto 0);
-		variable y: std_ulogic_vector(0 downto 0);
+        variable y     : std_ulogic_vector(0 downto 0);
-		variable z: std_ulogic_vector(0 downto 0);
+        variable z     : std_ulogic_vector(0 downto 0);
-		variable v : reg_type;
+        variable v     : reg_type;
-		variable v_int : reg_internal_type;
+        variable v_int : reg_internal_type;
-	begin
+    begin
-		v := r;
+        v := r;
-		v_int := r_int;
+        v_int := r_int;
-
+
-		x := "" & e_in.valid;
+        x := "" & e_in.valid;
-		y := "" & l_in.valid;
+        y := "" & l_in.valid;
-		z := "" & m_in.valid;
+        z := "" & m_in.valid;
-		assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z))) <= 1;
+        assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z))) <= 1 severity failure;
-
+
-		x := "" & e_in.write_enable;
+        x := "" & e_in.write_enable;
-		y := "" & l_in.write_enable;
+        y := "" & l_in.write_enable;
-		z := "" & m_in.write_reg_enable;
+        z := "" & m_in.write_reg_enable;
-		assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z))) <= 1;
+        assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z))) <= 1 severity failure;
-
+
-		assert not(e_in.write_cr_enable = '1' and m_in.write_cr_enable = '1');
+        assert not(e_in.write_cr_enable = '1' and m_in.write_cr_enable = '1');
-
+
-		v.w := WritebackToRegisterFileInit;
+        v.w := WritebackToRegisterFileInit;
-		v.c := WritebackToCrFileInit;
+        v.c := WritebackToCrFileInit;
-
+
-		v_int.complete := '0';
+        v_int.complete := '0';
-		if e_in.valid = '1' or l_in.valid = '1' or m_in.valid = '1' then
+        if e_in.valid = '1' or l_in.valid = '1' or m_in.valid = '1' then
-			v_int.complete := '1';
+            v_int.complete := '1';
-		end if;
+        end if;
-
+
-		if e_in.write_enable = '1' then
+        if e_in.write_enable = '1' then
-			v.w.write_reg := e_in.write_reg;
+            v.w.write_reg := e_in.write_reg;
-			v.w.write_data := e_in.write_data;
+            v.w.write_data := e_in.write_data;
-			v.w.write_enable := '1';
+            v.w.write_enable := '1';
-		end if;
+        end if;
-
+
-		if e_in.write_cr_enable = '1' then
+        if e_in.write_cr_enable = '1' then
-			v.c.write_cr_enable := '1';
+            v.c.write_cr_enable := '1';
-			v.c.write_cr_mask := e_in.write_cr_mask;
+            v.c.write_cr_mask := e_in.write_cr_mask;
-			v.c.write_cr_data := e_in.write_cr_data;
+            v.c.write_cr_data := e_in.write_cr_data;
-		end if;
+        end if;
-
+
-		if l_in.write_enable = '1' then
+        if l_in.write_enable = '1' then
-			v.w.write_reg := l_in.write_reg;
+            v.w.write_reg := l_in.write_reg;
-			v.w.write_data := l_in.write_data;
+            v.w.write_data := l_in.write_data;
-			v.w.write_enable := '1';
+            v.w.write_enable := '1';
-		end if;
+        end if;
-
+
-		if m_in.write_reg_enable = '1' then
+        if m_in.write_reg_enable = '1' then
-			v.w.write_enable := '1';
+            v.w.write_enable := '1';
-			v.w.write_reg := m_in.write_reg_nr;
+            v.w.write_reg := m_in.write_reg_nr;
-			v.w.write_data := m_in.write_reg_data;
+            v.w.write_data := m_in.write_reg_data;
-		end if;
+        end if;
-
+
-		if m_in.write_cr_enable = '1' then
+        if m_in.write_cr_enable = '1' then
-			v.c.write_cr_enable := '1';
+            v.c.write_cr_enable := '1';
-			v.c.write_cr_mask := m_in.write_cr_mask;
+            v.c.write_cr_mask := m_in.write_cr_mask;
-			v.c.write_cr_data := m_in.write_cr_data;
+            v.c.write_cr_data := m_in.write_cr_data;
-		end if;
+        end if;
-
+
-		-- Update registers
+        -- Update registers
-                rin <= v;
+        rin <= v;
-                rin_int <= v_int;
+        rin_int <= v_int;
-
+
-                -- Update outputs
+        -- Update outputs
-		complete_out <= r_int.complete;
+        complete_out <= r_int.complete;
-                w_out <= r.w;
+        w_out <= r.w;
-                c_out <= r.c;
+        c_out <= r.c;
-	end process;
+    end process;
 end;