X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=cpu%2Fsrc%2Falu_b.vhd;h=60a14bf867acc3aae5c85484d14c8f3b79581a9e;hb=d4a0ea68530da911bc41c44b24d244c7dc198190;hp=8399d6087e835d11d1375fc5a43e4c7d5bf10c27;hpb=37835209871e507ea3956c9fd616a6546b39d991;p=calu.git

diff --git a/cpu/src/alu_b.vhd b/cpu/src/alu_b.vhd
index 8399d60..60a14bf 100755
--- a/cpu/src/alu_b.vhd
+++ b/cpu/src/alu_b.vhd
@@ -1,158 +1,237 @@
-library IEEE;
-use IEEE.std_logic_1164.all;
-use IEEE.numeric_std.all;
-
-use work.alu_pkg.all;
-
-
-architecture behaviour of alu is
-	component exec_op is
-	port(
-		--System inputs
-		
-		clk : in std_logic;
-		reset : in std_logic;
-		--operation inputs
-		left_operand : in gp_register_t;
-		right_operand : in gp_register_t;
-		op_detail  : in op_opt_t;
-		alu_state  : in alu_result_rec;
-		alu_result : out alu_result_rec
-	);			
-	end component exec_op;
-	
+library IEEE;
+use IEEE.std_logic_1164.all;
+use IEEE.numeric_std.all;
+
+use work.alu_pkg.all;
+
+
+architecture behaviour of alu is
+	component exec_op is
+	port(
+		--System inputs
+		
+		clk : in std_logic;
+		reset : in std_logic;
+		--operation inputs
+		left_operand : in gp_register_t;
+		right_operand : in gp_register_t;
+		op_detail  : in op_opt_t;
+		alu_state  : in alu_result_rec;
+		alu_result : out alu_result_rec
+	);			
+	end component exec_op;
+	
 	signal add_result, and_result, or_result, xor_result, shift_result : alu_result_rec;
-        signal left, right : gp_register_t;
-	
-begin
-
-	add_inst : entity work.exec_op(add_op)
-	port map(clk,reset,left, right, op_detail, alu_state, add_result);
-	
-	and_inst : entity work.exec_op(and_op)
-	port map(clk,reset,left, right, op_detail, alu_state, and_result);
-
-	or_inst : entity work.exec_op(or_op)
-	port map(clk,reset,left, right, op_detail, alu_state, or_result);
-
-	xor_inst : entity work.exec_op(xor_op)
-	port map(clk,reset,left, right, op_detail, alu_state, xor_result);
-	
-	shift_inst : entity work.exec_op(shift_op)
-	port map(clk,reset,left, right, op_detail, alu_state, shift_result);
-
-calc: process(left_operand, right_operand,displacement, cond, op_group, op_detail ,alu_state,and_result,add_result,or_result,xor_result,shift_result)
-	variable result_v : alu_result_rec;
-	variable res_prod : std_logic;
-	variable cond_met : std_logic;
+        signal left_o, right_o : gp_register_t;
+	
+begin
+
+	add_inst : entity work.exec_op(add_op)
+	port map(clk,reset,left_o, right_o, op_detail, alu_state, add_result);
+	
+	and_inst : entity work.exec_op(and_op)
+	port map(clk,reset,left_o, right_o, op_detail, alu_state, and_result);
+
+	or_inst : entity work.exec_op(or_op)
+	port map(clk,reset,left_o, right_o, op_detail, alu_state, or_result);
+
+	xor_inst : entity work.exec_op(xor_op)
+	port map(clk,reset,left_o, right_o, op_detail, alu_state, xor_result);
+	
+	shift_inst : entity work.exec_op(shift_op)
+	port map(clk,reset,left_o, right_o, op_detail, alu_state, shift_result);
+
+calc: process(left_operand, right_operand,displacement, cond, op_group, op_detail ,alu_state,and_result,add_result,or_result,xor_result,shift_result, prog_cnt,brpr, pval, pval_nxt)
+	variable result_v : alu_result_rec;
+	variable res_prod : std_logic;
+	variable cond_met : std_logic;
 	variable mem_en : std_logic;
-        variable mem_op : std_logic;
-	variable alu_jmp : std_logic;
-begin
-	result_v := alu_state;
-	
-	res_prod := '1';
+   variable mem_op, hword_op, byte_op : std_logic;
+	variable alu_jump : std_logic;
+	variable nop     : std_logic;
+	
+	variable pinc_v, pwr_en_v : std_logic;
+	
+	variable prog_cnt_nxt : std_logic_vector(prog_cnt'range);
+begin
+	result_v := alu_state;
+	
+	res_prod := '1';
 	mem_en := '0';
-        mem_op := '0';
-	alu_jump := '0';
+    mem_op := '0';
+	 hword_op := '0';
+	 byte_op := '0';
+	alu_jump := '0';
   
-        left <= left_operand;
-        right <= right_operand;
+        left_o <= left_operand;
+        right_o <= right_operand;
 
         addr <= add_result.result;
-        data <= right_operand;
+        data <= right_operand;
+	
+	pinc_v := '0';
+	pwr_en_v := '0';
+	
+	paddr <= (others =>'0');
 	
 	result_v.result := add_result.result;
-
-	case cond is
-	when COND_NZERO =>
-		cond_met := not(alu_state.status.zero);
-	when COND_ZERO =>
-		cond_met := alu_state.status.zero;
-	when COND_NOFLO =>
-		cond_met := not(alu_state.status.oflo);
-	when COND_OFLO =>
-		cond_met := alu_state.status.oflo;
-	when COND_NCARRY =>
-		cond_met := not(alu_state.status.carry);
-	when COND_CARRY =>
-		cond_met := alu_state.status.carry;
-	when COND_NSIGN =>
-		cond_met := not(alu_state.status.sign);
-	when COND_SIGN =>
-		cond_met := alu_state.status.sign;
-	when COND_ABOVE =>
-		cond_met := not(alu_state.status.carry) and not(alu_state.status.zero);
-	when COND_BEQ =>
-		cond_met := alu_state.status.carry or alu_state.status.zero;
-	when COND_GEQ =>
-		cond_met := not(alu_state.status.sign xor alu_state.status.oflo);
-	when COND_LT =>
-		cond_met := alu_state.status.sign xor alu_state.status.oflo;
-	when COND_GT =>
-		cond_met := not(alu_state.status.zero) and not(alu_state.status.sign xor alu_state.status.oflo);
-	when COND_LEQ =>
-		cond_met := alu_state.status.zero or (alu_state.status.sign xor alu_state.status.oflo);
-	when COND_ALWAYS =>
-		cond_met := '1';
-	when COND_NEVER =>
-		cond_met := '0';
-	when others => null;
-	end case;
-	
-	cond_met := cond_met and (alu_state.alu_jmp xnor alu_state.brpr);
-
-	case op_group is
-	when ADDSUB_OP =>
-		result_v := add_result;
-	when AND_OP =>
-		result_v := and_result;
-	when OR_OP =>
-		result_v := or_result;
-	when XOR_OP =>
-		result_v := xor_result;
-	when SHIFT_OP =>
+	if (op_detail(DIRECT_JUMP_OPT) = '0') then
+		prog_cnt_nxt := std_logic_vector(unsigned(prog_cnt)+1);
+	else
+		prog_cnt_nxt := prog_cnt;
+	end if;
+	case cond is
+	when COND_NZERO =>
+		cond_met := not(alu_state.status.zero);
+	when COND_ZERO =>
+		cond_met := alu_state.status.zero;
+	when COND_NOFLO =>
+		cond_met := not(alu_state.status.oflo);
+	when COND_OFLO =>
+		cond_met := alu_state.status.oflo;
+	when COND_NCARRY =>
+		cond_met := not(alu_state.status.carry);
+	when COND_CARRY =>
+		cond_met := alu_state.status.carry;
+	when COND_NSIGN =>
+		cond_met := not(alu_state.status.sign);
+	when COND_SIGN =>
+		cond_met := alu_state.status.sign;
+	when COND_ABOVE =>
+		cond_met := not(alu_state.status.carry) and not(alu_state.status.zero);
+	when COND_BEQ =>
+		cond_met := alu_state.status.carry or alu_state.status.zero;
+	when COND_GEQ =>
+		cond_met := not(alu_state.status.sign xor alu_state.status.oflo);
+	when COND_LT =>
+		cond_met := alu_state.status.sign xor alu_state.status.oflo;
+	when COND_GT =>
+		cond_met := not(alu_state.status.zero) and not(alu_state.status.sign xor alu_state.status.oflo);
+	when COND_LEQ =>
+		cond_met := alu_state.status.zero or (alu_state.status.sign xor alu_state.status.oflo);
+	when COND_ALWAYS =>
+		cond_met := '1';
+	when COND_NEVER =>
+		cond_met := '0';
+	when others => null;
+	end case;
+	
+	nop := (alu_state.alu_jump xnor alu_state.brpr);
+	cond_met := cond_met and nop;
+
+	case op_group is
+	when ADDSUB_OP =>
+		result_v := add_result;
+	when AND_OP =>
+		result_v := and_result;
+	when OR_OP =>
+		result_v := or_result;
+	when XOR_OP =>
+		result_v := xor_result;
+	when SHIFT_OP =>
 		result_v := shift_result;
-        when LDST_OP =>
+   when LDST_OP =>
                 res_prod := '0';
                 mem_op := '1';
+		--right_o <= displacement;
+		addr <= std_logic_vector(unsigned(left_operand)+unsigned(displacement));
                 if op_detail(IMM_OPT) = '1' then
-                        result_v.result := right_operand;
+					 
+								result_v.result := right_operand;
+					 
+								if (op_detail(LDI_REPLACE_OPT) = '0') then
+									result_v.result := left_operand;
+									if (op_detail(LOW_HIGH_OPT) = '1') then
+										result_v.result(31 downto 16) := right_operand(31 downto 16);
+									else
+										result_v.result(15 downto 0) := right_operand(15 downto 0);
+									end if;
+								end if;
+
                         res_prod := '1';
                         mem_op := '0';
                 end if;
                 if op_detail(ST_OPT) = '1' then
-                        right <= displacement;
                         mem_en := '1';
                 end if;
+					 
+					 hword_op := op_detail(HWORD_OPT);
+					 byte_op := op_detail(BYTE_OPT);
+					 
 	when JMP_OP =>
 		if op_detail(JMP_REG_OPT) = '0' then
-			left <= prog_cnt;
+			left_o <= prog_cnt;
+		end if;
+		alu_jump := '1';
+	when JMP_ST_OP => 
+		left_o <= prog_cnt;
+		mem_en := '1';
+		alu_jump := '1';
+		mem_op := '1';
+		pinc_v := '1';
+		pwr_en_v := '1';
+		paddr <= (others =>'0');
+		
+		addr <= pval;
+		data <= prog_cnt_nxt;
+		if op_detail(RET_OPT) = '1' then
+			addr <= pval_nxt;
+			mem_en := '0';
+			pinc_v := '0';
+			res_prod := '0';
 		end if;
-		result_v.alu_jmp := '1';
-	when JMP_ST_OP => null;
-	end case;
-	
-
-	result_v.status.zero := '0';
-	if result_v.result = REG_ZERO then
-		result_v.status.zero := '1';
-	end if;
-	
-	result_v.status.sign := result_v.result(gp_register_t'high);
-
-	if (op_detail(NO_PSW_OPT) = '1') or (cond_met = '0') then
-		result_v.status := alu_state.status;
-	end if;
-	
-	result_v.reg_op := not(op_detail(NO_DST_OPT)) and res_prod and cond_met;
+	when STACK_OP =>
+		mem_op := '1';
+		pwr_en_v := op_detail(PWREN_OPT);
+		if op_detail(PUSH_OPT) = '1' then
+			mem_en := '1';
+			pinc_v := '1';
+			res_prod := '0';
+			addr <= pval;
+			data <= left_operand;
+		else
+			addr <= pval_nxt;
+		end if;
+		
+	end case;
+	
+
+	result_v.status.zero := '0';
+	if result_v.result = REG_ZERO then
+		result_v.status.zero := '1';
+	end if;
+	
+	result_v.status.sign := result_v.result(gp_register_t'high);
+
+	if (op_detail(NO_PSW_OPT) = '1') or (cond_met = '0') then
+		result_v.status := alu_state.status;
+	end if;
+	
+	result_v.reg_op := not(op_detail(NO_DST_OPT)) and res_prod and cond_met;
 	result_v.mem_en := mem_en and cond_met;
-        result_v.mem_op := mem_op and cond_met;
-	result_v.alu_jmp := alu_jmp and cond_met;
-        
-	alu_result <= result_v;
-	
-end process calc; 
-
-end architecture behaviour;
-
+    result_v.mem_op := mem_op and cond_met;
+	result_v.alu_jump := alu_jump and cond_met;
+	result_v.brpr := brpr and nop;
+	
+	result_v.hw_op := hword_op and cond_met;
+	result_v.byte_op := byte_op and cond_met;
+	
+	pwr_en_v := pwr_en_v and cond_met;
+        
+	if (result_v.alu_jump = '0') and (brpr = '1') then
+		result_v.result := (others => '0');
+		result_v.result(prog_cnt'range) := prog_cnt_nxt;
+		--result_v.reg_op := '1';
+	end if;
+
+	-- if result_v.mem_op = '0' then --- do this if selecting enable for extension modules is too slow.
+		-- addr <= (others => '0');
+	-- end if;
+	alu_result <= result_v;
+	pinc <= pinc_v;
+	pwr_en <= pwr_en_v;
+	
+end process calc; 
+
+end architecture behaviour;
+