Share soc.vhdl between FPGA and sim

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Makefile

@@ -12,7 +12,7 @@ all: $(all)
 	$(GHDL) -a $(GHDLFLAGS) $<
 
 common.o: decode_types.o
-core_tb.o: common.o wishbone_types.o core.o simple_ram_behavioural.o sim_uart.o
+core_tb.o: common.o core.o soc.o
 core.o: common.o wishbone_types.o fetch1.o fetch2.o decode1.o decode2.o register_file.o cr_file.o execute1.o execute2.o loadstore1.o loadstore2.o multiply.o writeback.o wishbone_arbiter.o
 cr_file.o: common.o
 crhelpers.o: common.o
@@ -41,6 +41,7 @@ simple_ram_behavioural.o: wishbone_types.o simple_ram_behavioural_helpers.o
 wishbone_arbiter.o: wishbone_types.o
 wishbone_types.o:
 writeback.o: common.o
+soc.o: wishbone_types.o simple_ram_behavioural.o sim_uart.o
 
 fpga/soc_reset_tb.o: fpga/soc_reset.o
 

core_tb.vhdl

@@ -13,88 +13,23 @@ end core_tb;
 architecture behave of core_tb is
 	signal clk, rst: std_logic;
 
-	signal wishbone_dcore_in : wishbone_slave_out;
-	signal wishbone_dcore_out : wishbone_master_out;
-
-	signal wishbone_icore_in : wishbone_slave_out;
-	signal wishbone_icore_out : wishbone_master_out;
-
-	signal wishbone_core_in : wishbone_slave_out;
-	signal wishbone_core_out : wishbone_master_out;
-
-	signal wishbone_ram_in : wishbone_slave_out;
-	signal wishbone_ram_out : wishbone_master_out;
-
-	signal wishbone_uart_in : wishbone_slave_out;
-	signal wishbone_uart_out : wishbone_master_out;
-
-	signal registers : regfile;
-	signal terminate : std_ulogic;
-
 	-- testbench signals
 	constant clk_period : time := 10 ns;
 begin
-	core_0: entity work.core
-		generic map (SIM => true)
-	    port map (clk => clk, rst => rst,
-		      wishbone_insn_in => wishbone_icore_in,
-		      wishbone_insn_out => wishbone_icore_out,
-		      wishbone_data_in => wishbone_dcore_in,
-		      wishbone_data_out => wishbone_dcore_out,
-		      registers => registers, terminate_out => terminate);
-
-	simple_ram_0: entity work.simple_ram_behavioural
-		generic map ( filename => "simple_ram_behavioural.bin", size => 524288)
-		port map (clk => clk, rst => rst, wishbone_in => wishbone_ram_out, wishbone_out => wishbone_ram_in);
-
-	simple_uart_0: entity work.sim_uart
-		port map ( clk => clk, reset => rst, wishbone_in => wishbone_uart_out, wishbone_out => wishbone_uart_in);
-
-
-	wishbone_arbiter_0: entity work.wishbone_arbiter
-		port map (clk => clk, rst => rst,
-			  wb1_in => wishbone_dcore_out, wb1_out => wishbone_dcore_in,
-			  wb2_in => wishbone_icore_out, wb2_out => wishbone_icore_in,
-			  wb_out => wishbone_core_out, wb_in => wishbone_core_in);
-
-	bus_process: process(wishbone_core_out, wishbone_ram_in, wishbone_uart_in)
-	  -- Selected slave
-	  type slave_type is (SLAVE_UART, SLAVE_MEMORY, SLAVE_NONE);
-	  variable slave : slave_type;
-	begin
-		-- Simple address decoder
-		slave := SLAVE_NONE;
-		if wishbone_core_out.adr(31 downto 24) = x"00" then
-			slave := SLAVE_MEMORY;
-		elsif wishbone_core_out.adr(31 downto 24) = x"c0" then
-			if wishbone_core_out.adr(15 downto 12) = x"2" then
-				slave := SLAVE_UART;
-			end if;
-		end if;
 
-		-- Wishbone muxing:
-		-- Start with all master signals to all slaves, then override
-		-- cyc and stb accordingly
-		wishbone_ram_out <= wishbone_core_out;
-		wishbone_uart_out <= wishbone_core_out;
-		if slave = SLAVE_MEMORY then
-			wishbone_core_in <= wishbone_ram_in;
-		else
-			wishbone_ram_out.cyc <= '0';
-			wishbone_ram_out.stb <= '0';
-		end if;
-		if slave = SLAVE_UART then
-			wishbone_core_in <= wishbone_uart_in;
-		else
-			wishbone_uart_out.cyc <= '0';
-			wishbone_uart_out.stb <= '0';
-		end if;
-		if slave = SLAVE_NONE then
-			wishbone_core_in.dat <= (others => '1');
-			wishbone_core_in.ack <= wishbone_core_out.cyc and
-						wishbone_core_out.stb;
-		end if;
-	end process;
+    soc0: entity work.soc
+	generic map(
+	    SIM => true,
+	    MEMORY_SIZE => 524288,
+	    RAM_INIT_FILE => "simple_ram_behavioural.bin",
+	    RESET_LOW => false
+	    )
+	port map(
+	    rst => rst,
+	    system_clk => clk,
+	    uart0_rxd => '0',
+	    uart0_txd => open
+	    );
 
 	clk_process: process
 	begin
@@ -111,14 +46,4 @@ begin
 		rst <= '0';
 		wait;
 	end process;
-
-	dump_registers: process(all)
-	begin
-		if terminate = '1' then
-			loop_0: for i in 0 to 31 loop
-				report "REG " & to_hstring(registers(i));
-			end loop loop_0;
-			assert false report "end of test" severity failure;
-		end if;
-	end process;
 end;

fpga/toplevel.vhdl

@@ -55,7 +55,8 @@ begin
 	generic map(
 	    MEMORY_SIZE   => MEMORY_SIZE,
 	    RAM_INIT_FILE => RAM_INIT_FILE,
-	    RESET_LOW     => RESET_LOW
+	    RESET_LOW     => RESET_LOW,
+	    SIM           => false
 	    )
 	port map (
 	    system_clk        => system_clk,

microwatt.core

@@ -24,19 +24,23 @@ filesets:
       - loadstore2.vhdl
       - multiply.vhdl
       - writeback.vhdl
-      - wishbone_arbiter.vhdl
       - insn_helpers.vhdl
       - core.vhdl
     file_type : vhdlSource-2008
 
   soc:
+    files:
+      - wishbone_arbiter.vhdl
+      - soc.vhdl
+    file_type : vhdlSource-2008
+
+  fpga:
     files:
       - fpga/pp_fifo.vhd
       - fpga/mw_soc_memory.vhdl
       - fpga/soc_reset.vhdl
       - fpga/pp_soc_uart.vhd
       - fpga/pp_utilities.vhd
-      - fpga/soc.vhdl
       - fpga/toplevel.vhdl
       - fpga/firmware.hex : {copyto : firmware.hex, file_type : user}
     file_type : vhdlSource-2008
@@ -64,7 +68,7 @@ filesets:
 targets:
   nexys_a7:
     default_tool: vivado
-    filesets: [core, nexys_a7, soc]
+    filesets: [core, nexys_a7, soc, fpga]
     parameters : [memory_size, ram_init_file]
     tools:
       vivado: {part : xc7a100tcsg324-1}
@@ -72,7 +76,7 @@ targets:
 
   nexys_video:
     default_tool: vivado
-    filesets: [core, nexys_video, soc]
+    filesets: [core, nexys_video, soc, fpga]
     parameters : [memory_size, ram_init_file]
     tools:
       vivado: {part : xc7a200tsbg484-1}
@@ -80,7 +84,7 @@ targets:
 
   arty_a7-35:
     default_tool: vivado
-    filesets: [core, arty_a7-35, soc]
+    filesets: [core, arty_a7-35, soc, fpga]
     parameters : [memory_size, ram_init_file]
     tools:
       vivado: {part : xc7a35ticsg324-1L}
@@ -88,14 +92,14 @@ targets:
 
   cmod_a7-35:
     default_tool: vivado
-    filesets: [core, cmod_a7-35, soc]
+    filesets: [core, cmod_a7-35, soc, fpga]
     parameters : [memory_size, ram_init_file, reset_low=false]
     tools:
       vivado: {part : xc7a35tcpg236-1}
     toplevel : toplevel
 
   synth:
-    filesets: [core]
+    filesets: [core, soc]
     tools:
       vivado: {pnr : none}
     toplevel: core

sim_uart.vhdl

@@ -31,18 +31,30 @@ use work.sim_console.all;
 --! enable register. The following bits are available:
 --! - Bit 0: data received (receive buffer not empty)
 --! - Bit 1: ready to send data (transmit buffer empty)
-entity sim_uart is
+entity pp_soc_uart is
+    generic(
+	FIFO_DEPTH : natural := 64 --Unused
+	);
     port(
 	clk : in std_logic;
 	reset : in std_logic;
 
+	-- UART ports:
+	txd : out std_logic;
+	rxd : in  std_logic;
+
 	-- Wishbone ports:
-	wishbone_in : in wishbone_master_out;
-	wishbone_out : out wishbone_slave_out
+	wb_adr_in  : in  std_logic_vector(11 downto 0);
+	wb_dat_in  : in  std_logic_vector( 7 downto 0);
+	wb_dat_out : out std_logic_vector( 7 downto 0);
+	wb_we_in   : in  std_logic;
+	wb_cyc_in  : in  std_logic;
+	wb_stb_in  : in  std_logic;
+	wb_ack_out : out std_logic
 	);
-end entity sim_uart;
+end entity pp_soc_uart;
 
-architecture behaviour of sim_uart is
+architecture behaviour of pp_soc_uart is
 
     signal sample_clk_divisor : std_logic_vector(7 downto 0);
 
@@ -56,7 +68,7 @@ architecture behaviour of sim_uart is
 
 begin
 
-    wishbone_out.ack <= wb_ack and wishbone_in.cyc and wishbone_in.stb;
+    wb_ack_out <= wb_ack and wb_cyc_in and wb_stb_in;
 
     wishbone: process(clk)
 	variable sim_tmp : std_logic_vector(63 downto 0);
@@ -71,42 +83,40 @@ begin
 	    else
 		case wb_state is
 		when IDLE =>
-		    if wishbone_in.cyc = '1' and wishbone_in.stb = '1' then
-			if wishbone_in.we = '1' then -- Write to register
-			    if wishbone_in.adr(11 downto 0) = x"000" then
-				report "FOO !";
-				sim_console_write(wishbone_in.dat);
-			    elsif wishbone_in.adr(11 downto 0) = x"018" then
-				sample_clk_divisor <= wishbone_in.dat(7 downto 0);
-			    elsif wishbone_in.adr(11 downto 0) = x"020" then
-				irq_recv_enable <= wishbone_in.dat(0);
-				irq_tx_ready_enable <= wishbone_in.dat(1);
+		    if wb_cyc_in = '1' and wb_stb_in = '1' then
+			if wb_we_in = '1' then -- Write to register
+			    if wb_adr_in(11 downto 0) = x"000" then
+				sim_console_write(x"00000000000000" & wb_dat_in);
+			    elsif wb_adr_in(11 downto 0) = x"018" then
+				sample_clk_divisor <= wb_dat_in;
+			    elsif wb_adr_in(11 downto 0) = x"020" then
+				irq_recv_enable <= wb_dat_in(0);
+				irq_tx_ready_enable <= wb_dat_in(1);
 			    end if;
 			    wb_ack <= '1';
 			    wb_state <= WRITE_ACK;
 			else -- Read from register
-			    if wishbone_in.adr(11 downto 0) = x"008" then
+			    if wb_adr_in(11 downto 0) = x"008" then
 				sim_console_read(sim_tmp);
-				wishbone_out.dat <= sim_tmp;
-			    elsif wishbone_in.adr(11 downto 0) = x"010" then
+				wb_dat_out <= sim_tmp(7 downto 0);
+			    elsif wb_adr_in(11 downto 0) = x"010" then
 				sim_console_poll(sim_tmp);
-				wishbone_out.dat <= x"000000000000000" & '0' &
-						    sim_tmp(0) & '1' & not sim_tmp(0);
-			    elsif wishbone_in.adr(11 downto 0) = x"018" then
-				wishbone_out.dat <= x"00000000000000" & sample_clk_divisor;
-			    elsif wishbone_in.adr(11 downto 0) = x"020" then
-				wishbone_out.dat <= (0 => irq_recv_enable,
+				wb_dat_out <= "00000" & sim_tmp(0) & '1' & not sim_tmp(0);
+			    elsif wb_adr_in(11 downto 0) = x"018" then
+				wb_dat_out <= sample_clk_divisor;
+			    elsif wb_adr_in(11 downto 0) = x"020" then
+				wb_dat_out <= (0 => irq_recv_enable,
 					       1 => irq_tx_ready_enable,
 					       others => '0');
 			    else
-				wishbone_out.dat <= (others => '0');
+				wb_dat_out <= (others => '0');
 			    end if;
 			    wb_ack <= '1';
 			    wb_state <= READ_ACK;
 			end if;
 		    end if;
 		when WRITE_ACK|READ_ACK =>
-		    if wishbone_in.stb = '0' then
+		    if wb_stb_in = '0' then
 			wb_ack <= '0';
 			wb_state <= IDLE;
 		    end if;

simple_ram_behavioural.vhdl

@@ -7,10 +7,10 @@ library work;
 use work.wishbone_types.all;
 use work.simple_ram_behavioural_helpers.all;
 
-entity simple_ram_behavioural is
+entity mw_soc_memory is
 	generic (
-		FILENAME : string;
-		SIZE     : integer
+		RAM_INIT_FILE : string;
+		MEMORY_SIZE   : integer
 	);
 
 	port (
@@ -20,14 +20,14 @@ entity simple_ram_behavioural is
 		wishbone_in  : in wishbone_master_out;
 		wishbone_out : out wishbone_slave_out
 	);
-end simple_ram_behavioural;
+end mw_soc_memory;
 
-architecture behave of simple_ram_behavioural is
+architecture behave of mw_soc_memory is
 	type wishbone_state_t is (IDLE, ACK);
 
 	signal state      : wishbone_state_t := IDLE;
 	signal ret_ack    : std_ulogic := '0';
-	signal identifier : integer := behavioural_initialize(filename => FILENAME, size => SIZE);
+	signal identifier : integer := behavioural_initialize(filename => RAM_INIT_FILE, size => MEMORY_SIZE);
 	signal reload     : integer := 0;
 begin
 	wishbone_process: process(clk)

simple_ram_behavioural_tb.vhdl

@@ -17,8 +17,8 @@ architecture behave of simple_ram_behavioural_tb is
 	signal w_in         : wishbone_slave_out;
 	signal w_out        : wishbone_master_out;
 begin
-	simple_ram_0: entity work.simple_ram_behavioural
-		generic map ( filename => "simple_ram_behavioural_tb.bin", size => 16 )
+	simple_ram_0: entity work.mw_soc_memory
+		generic map ( RAM_INIT_FILE => "simple_ram_behavioural_tb.bin", MEMORY_SIZE => 16 )
 		port map (clk => clk, rst => rst, wishbone_out => w_in, wishbone_in => w_out);
 
 	clock: process

soc.vhdl

@@ -2,7 +2,10 @@ library ieee;
 use ieee.std_logic_1164.all;
 use ieee.math_real.all;
 
+use std.textio.all;
+
 library work;
+use work.common.all;
 use work.wishbone_types.all;
 
 
@@ -12,7 +15,8 @@ entity soc is
     generic (
 	MEMORY_SIZE   : positive;
 	RAM_INIT_FILE : string;
-	RESET_LOW     : boolean
+	RESET_LOW     : boolean;
+	SIM           : boolean
 	);
     port(
 	rst          : in  std_ulogic;
@@ -37,30 +41,35 @@ architecture behaviour of soc is
     signal wb_master_out : wishbone_master_out;
 
     -- UART0 signals:
-    signal uart0_adr_in  : std_logic_vector(11 downto 0);
-    signal uart0_dat_in  : std_logic_vector( 7 downto 0);
-    signal uart0_dat_out : std_logic_vector( 7 downto 0);
-    signal uart0_cyc_in  : std_logic;
-    signal uart0_stb_in  : std_logic;
-    signal uart0_we_in   : std_logic;
-    signal uart0_ack_out : std_logic;
+    signal wb_uart0_in   : wishbone_master_out;
+    signal wb_uart0_out  : wishbone_slave_out;
+    signal uart_dat8     : std_logic_vector(7 downto 0);
 
     -- Main memory signals:
     signal wb_bram_in     : wishbone_master_out;
     signal wb_bram_out    : wishbone_slave_out;
     constant mem_adr_bits : positive := positive(ceil(log2(real(MEMORY_SIZE))));
 
+    -- Debug signals (used in SIM only)
+    signal registers     : regfile;
+    signal terminate     : std_ulogic;
+
 begin
 
     -- Processor core
     processor: entity work.core
+	generic map(
+	    SIM => SIM
+	    )
 	port map(
 	    clk => system_clk,
 	    rst => rst,
 	    wishbone_insn_in => wishbone_icore_in,
 	    wishbone_insn_out => wishbone_icore_out,
 	    wishbone_data_in => wishbone_dcore_in,
-	    wishbone_data_out => wishbone_dcore_out
+	    wishbone_data_out => wishbone_dcore_out,
+	    registers => registers,
+	    terminate_out => terminate
 	    );
 
     -- Wishbone bus master arbiter & mux
@@ -77,8 +86,7 @@ begin
 	    );
 
     -- Wishbone slaves address decoder & mux
-    slave_intercon: process(wb_master_out,  wb_bram_out,
-			    uart0_ack_out, uart0_dat_out)
+    slave_intercon: process(wb_master_out, wb_bram_out, wb_uart0_out)
 	-- Selected slave
 	type slave_type is (SLAVE_UART,
 			    SLAVE_MEMORY,
@@ -98,22 +106,42 @@ begin
 	-- Wishbone muxing. Defaults:
 	wb_bram_in <= wb_master_out;
 	wb_bram_in.cyc  <= '0';
-	uart0_cyc_in <= '0';
+	wb_uart0_in <= wb_master_out;
+	wb_uart0_in.cyc <= '0';
 	case slave is
 	when SLAVE_MEMORY =>
 	    wb_bram_in.cyc <= wb_master_out.cyc;
 	    wb_master_in <= wb_bram_out;
 	when SLAVE_UART =>
-	    uart0_cyc_in <= wb_master_out.cyc;
-	    wb_master_in.ack <= uart0_ack_out;
-	    wb_master_in.dat <= x"00000000000000" & uart0_dat_out;
+	    wb_uart0_in.cyc <= wb_master_out.cyc;
+	    wb_master_in <= wb_uart0_out;
 	when others =>
 	    wb_master_in.dat <= (others => '1');
 	    wb_master_in.ack <= wb_master_out.stb and wb_master_out.cyc;
 	end case;
     end process slave_intercon;
 
+    -- Simulated memory and UART
+    sim_terminate_test: if SIM generate
+
+	-- Dump registers if core terminates
+	dump_registers: process(all)
+	begin
+	    if terminate = '1' then
+		loop_0: for i in 0 to 31 loop
+		    report "REG " & to_hstring(registers(i));
+		end loop loop_0;
+		assert false report "end of test" severity failure;
+	    end if;
+	end process;
+
+    end generate;
+
     -- UART0 wishbone slave
+    -- XXX FIXME: Need a proper wb64->wb8 adapter that
+    --            converts SELs into low address bits and muxes
+    --            data accordingly (either that or rejects large
+    --            cycles).
     uart0: entity work.pp_soc_uart
 	generic map(
 	    FIFO_DEPTH => 32
@@ -123,22 +151,15 @@ begin
 	    reset => rst,
 	    txd => uart0_txd,
 	    rxd => uart0_rxd,
-	    wb_adr_in => uart0_adr_in,
-	    wb_dat_in => uart0_dat_in,
-	    wb_dat_out => uart0_dat_out,
-	    wb_cyc_in => uart0_cyc_in,
-	    wb_stb_in => uart0_stb_in,
-	    wb_we_in => uart0_we_in,
-	    wb_ack_out => uart0_ack_out
+	    wb_adr_in => wb_uart0_in.adr(11 downto 0),
+	    wb_dat_in => wb_uart0_in.dat(7 downto 0),
+	    wb_dat_out => uart_dat8,
+	    wb_cyc_in => wb_uart0_in.cyc,
+	    wb_stb_in => wb_uart0_in.stb,
+	    wb_we_in => wb_uart0_in.we,
+	    wb_ack_out => wb_uart0_out.ack
 	    );
-    -- Wire it up: XXX FIXME: Need a proper wb64->wb8 adapter that
-    --                 converts SELs into low address bits and muxes
-    --                 data accordingly (either that or rejects large
-    --                 cycles).
-    uart0_adr_in <= wb_master_out.adr(uart0_adr_in'range);
-    uart0_dat_in <= wb_master_out.dat(7 downto 0);
-    uart0_we_in  <= wb_master_out.we;
-    uart0_stb_in <= wb_master_out.stb;
+    wb_uart0_out.dat <= x"00000000000000" & uart_dat8;
 
     -- BRAM Memory slave
     bram0: entity work.mw_soc_memory