Initial revision

Committed on the Free edition of March Hare Software CVSNT Server.
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git-svn-id: http://moon:8086/svn/vhdl/branches/EMAC_BRANCH_DMA@1035 cc03376c-175c-47c8-b038-4cd826a8556b

lib/emac/sim/tb_emac_top_jb.fdo

@@ -3,14 +3,19 @@
 ##
 vlib work
 vcom -explicit  -93 "../../misc/utils_pkg.vhd"
-vcom -explicit  -93 "../../misc/dpram_1w1r.vhd"
-vcom -explicit  -93 "../../misc/dpram_2w2r.vhd"
+vcom -explicit  -93 "../../rams/dpram_1w1r2c_ra_sim.vhd"
+vcom -explicit  -93 "../../rams/dpram_2w2r2c_ra_sim.vhd"
+vcom -explicit  -93 "../../rams/dpram_1w1r2c_ro_sim.vhd"
+vcom -explicit  -93 "../../rams/dpram_2w2r2c_ro_sim.vhd"
 vcom -explicit  -93 "../../FIFO/src/fifo_ctrl_pkg.vhd"
 vcom -explicit  -93 "../../FIFO/src/fifo_sync_ctrl.vhd"
 vcom -explicit  -93 "../../FIFO/src/fifo_sync.vhd"
 vcom -explicit  -93 "../../FIFO/src/gray_counter.vhd"
 vcom -explicit  -93 "../../FIFO/src/fifo_async_ctrl.vhd"
 vcom -explicit  -93 "../../FIFO/src/fifo_async.vhd"
+vcom -explicit  -93 "../../JBUS/src/busmaster_types.vhd"
+vcom -explicit  -93 "../../JBUS/src/busmaster_sync.vhd"
+vcom -explicit  -93 "../../JBUS/src/dmac.vhd"
 vcom -explicit  -93 "../src/piso.vhd"
 vcom -explicit  -93 "../src/sipo.vhd"
 vcom -explicit  -93 "../src/crc32.vhd"
@@ -26,4 +31,4 @@ do {tb_emac_top_jb.wdo}
 view structure
 view signals
 
-run 50000 us
+run 16000 us

lib/emac/sim/tb_emac_top_jb.wdo

@@ -3,6 +3,8 @@ quietly WaveActivateNextPane {} 0
 add wave -noupdate -divider {Ethernet MAC}
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/clk_i
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/rst_i
+add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/ram64
+add wave -noupdate -divider Slave
 add wave -noupdate -format Logic -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/int_o
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/cyc_i
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/stb_i
@@ -14,6 +16,18 @@ add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/mrdy_i
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/addr_i
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/dat_i
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/dat_o
+add wave -noupdate -divider Master
+add wave -noupdate -format Logic /tb_emac_top_jb/cyc_o
+add wave -noupdate -format Logic /tb_emac_top_jb/stb_o
+add wave -noupdate -format Logic /tb_emac_top_jb/we_o
+add wave -noupdate -format Literal /tb_emac_top_jb/sel_o
+add wave -noupdate -format Logic /tb_emac_top_jb/ack_i
+add wave -noupdate -format Logic /tb_emac_top_jb/mrdy_o
+add wave -noupdate -format Logic /tb_emac_top_jb/srdy_i
+add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/addr_o
+add wave -noupdate -format Literal /tb_emac_top_jb/mdat_i
+add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/mdat_o
+add wave -noupdate -divider MII
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/mii_rx_clk
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/mii_rx_dv
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/mii_rx_er
@@ -53,10 +67,25 @@ add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/pktgen_tx
 add wave -noupdate -format Logic /tb_emac_top_jb/pktgen_tx_en
 add wave -noupdate -format Logic /tb_emac_top_jb/pktgen_tx_er
 add wave -noupdate -format Logic /tb_emac_top_jb/pktgen_en
+add wave -noupdate -divider RX-DMA
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/master_req
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/master_gnt
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/dma_start
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/dma_active
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/dma_end
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_rdy
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_en
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_rw
+add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_addr_start
+add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_num_xfers
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_addr_auto_inc
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_complete
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/req_complete_ack
+add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/gen_dmac__0/inst_dmac/s
 add wave -noupdate -divider RX
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/clk
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/rst
-add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/dout_vld
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/dout_re
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/dout
 add wave -noupdate -format Literal -radix hexadecimal -expand /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/ctrl_in
 add wave -noupdate -format Literal -radix unsigned -expand /tb_emac_top_jb/inst_emac_top_jb/inst_emac_rx/ctrl_out
@@ -159,8 +188,6 @@ add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/ram_en_b
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/ram_addr_b
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/ram_dout_b
-add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/ifg_cnt
-add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/ifg_idle
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_din
 add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_din_be
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_din_rdy
@@ -168,6 +195,11 @@ add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/p
 add wave -noupdate -format Literal -radix hexadecimal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_dout
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_dout_vld
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso32_dout_en
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mii_fifo_we
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mii_fifo_re
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mii_fifo_full
+add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mii_fifo_empty
+add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mii_fifo_re_dly
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso8_din_vld
 add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso8_din
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/piso8_dout_vld
@@ -187,7 +219,7 @@ add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx
 add wave -noupdate -format Logic /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mem_free_req
 add wave -noupdate -format Literal /tb_emac_top_jb/inst_emac_top_jb/inst_emac_tx/mem_free_ack
 TreeUpdate [SetDefaultTree]
-WaveRestoreCursors {{Cursor 1} {11284359462 ps} 0} {{Cursor 2} {49999967706 ps} 0} {{Cursor 3} {49999529250 ps} 0}
+WaveRestoreCursors {{Cursor 1} {15999470765 ps} 0} {{Cursor 2} {49999967706 ps} 0} {{Cursor 3} {42725669958 ps} 0} {{Cursor 4} {10461803096 ps} 0} {{Cursor 5} {10000 ps} 0}
 configure wave -namecolwidth 150
 configure wave -valuecolwidth 100
 configure wave -justifyvalue left
@@ -201,4 +233,4 @@ configure wave -gridperiod 100
 configure wave -griddelta 40
 configure wave -timeline 1
 update
-WaveRestoreZoom {11283753554 ps} {11286295500 ps}
+WaveRestoreZoom {0 ps} {379173 ps}

lib/emac/src/crc32.vhd

@@ -50,11 +50,12 @@ begin
 process(clk)
 begin
 	if rising_edge(clk) then
-		crc32_vld	<= not rst and din_vld;
 		if rst = '1' then
 			crc0		<= crc32_init;
+			crc32_vld	<= '0';
 		elsif din_vld = '1' then	
 			crc0		<= crc2;
+			crc32_vld	<= '1';
 		end if;
 	end if;
 end process;

lib/emac/src/emac_rx.vhd

@@ -16,7 +16,7 @@ ENTITY emac_rx IS
 	(
 		clk				: in  STD_LOGIC;
 		rst				: in  STD_LOGIC;
-		dout_vld		: out STD_LOGIC;
+		dout_re			: in  STD_LOGIC;
 		dout			: out unsigned(31 downto 0);
 		ctrl_in			: in  rx_ctrl_in_t;
 		ctrl_out		: out rx_ctrl_out_t;
@@ -47,6 +47,7 @@ ARCHITECTURE behavior OF emac_rx IS
 	signal reset_en			: std_logic;
 	
 	signal host_ptr			: word_ptr_t;
+	signal host_ptr_next	: word_ptr_t;
 	signal host_ram_limit	: word_ptr_t;
 	signal host_ram_base	: word_ptr_t;
 
@@ -143,7 +144,7 @@ begin
 	dout					<= ram_dout_b;
 
 	ram_en_b				<= '1';
-	ram_addr_b				<= host_ptr;
+	ram_addr_b				<= host_ptr_next;
 
 	ram_en_a				<= '1';
 	ram_din_a				<= sipo32_dout;
@@ -183,15 +184,16 @@ fill_pointer:
 	process(clk)
 	begin
 		if rising_edge(clk) then
-			dout_vld			<= ctrl_in.pkt_read_en;
 			if ctrl_in.pkt_req_en = '1' then
 				host_ptr		<= cmd_base_out;
-			elsif ctrl_in.pkt_read_en = '1' then
-				host_ptr		<= host_ptr + 1;
+			elsif dout_re = '1' then
+				host_ptr		<= host_ptr_next;
 			end if;
 		end if;
 	end process;	
 
+	host_ptr_next	<= host_ptr + 1 when dout_re = '1' else host_ptr;
+	
 ------------------------------------------------------------------
 -- Transfer stuff
 ------------------------------------------------------------------
@@ -444,7 +446,7 @@ inst_cmd_fifo: entity work.fifo_async
 		data_r		=>  cmd_fifo_dout
 	);
 
-inst_ram : entity work.dpram_1w1r
+inst_ram : entity work.dpram_1w1r2c_ro
 	GENERIC MAP 
 	(
 		addr_width	=> RAM_ADDR_WIDTH,
@@ -452,8 +454,8 @@ inst_ram : entity work.dpram_1w1r
 	)
 	PORT MAP 
 	(
-		clka		=> mii_rx_clk,
-		clkb		=> clk,
+		clk_a		=> mii_rx_clk,
+		clk_b		=> clk,
 		en_a		=> ram_en_a,
 		en_b		=> ram_en_b,
 		we_a		=> ram_we_a,

lib/emac/src/emac_top_jb.vhd

@@ -5,6 +5,7 @@ use std.textio.all; --  Imports the standard textio package.
 
 use work.emac_types.all;
 use work.utils_pkg.all;
+use work.busmaster_types.all;
 
 ENTITY emac_top_jb IS
 	Generic
@@ -15,6 +16,7 @@ ENTITY emac_top_jb IS
 	);
 	Port
 	(
+		-- JBUS Slave
 		CLK_I		: in  STD_LOGIC;
 		RST_I		: in  STD_LOGIC;
 		INT_O		: out STD_LOGIC;
@@ -28,6 +30,20 @@ ENTITY emac_top_jb IS
 		ADDR_I		: in  unsigned(31 downto 0);
 		DAT_I		: in  unsigned(31 downto 0);
 		DAT_O		: out unsigned(31 downto 0);
+		
+		-- JBUS Master
+		ACK_I		: in std_logic;
+		SRDY_I		: in std_logic;
+		MDAT_I		: in unsigned(31 downto 0);
+		MDAT_O		: out unsigned(31 downto 0);
+		ADDR_O		: out unsigned(31 downto 0);
+		SEL_O		: out unsigned(3 downto 0);
+		WE_O		: out std_logic;
+		CYC_O		: out std_logic;
+		STB_O		: out std_logic;
+		MRDY_O		: out std_logic;
+		
+		-- MII
 		mii_rx_clk	: in  STD_LOGIC;
 		mii_rx_dv	: in  STD_LOGIC;
 		mii_rx_er	: in  STD_LOGIC;
@@ -45,6 +61,12 @@ END emac_top_jb;
 
 ARCHITECTURE behavior OF emac_top_jb IS
 
+	-- Constants
+	constant DMA_NUM_CHANNEL		: integer := 2;
+	constant DMA_CH_WRITE			: integer := 0;
+	constant DMA_CH_READ			: integer := 1;
+	constant DMA_RW_CONF			: unsigned(DMA_NUM_CHANNEL-1 downto 0) := "01";
+
 	-- Signals for EMAC connections
 	signal tx_ctrl_in		: tx_ctrl_in_t;
 	signal tx_ctrl_out		: tx_ctrl_out_t;
@@ -55,7 +77,7 @@ ARCHITECTURE behavior OF emac_top_jb IS
 	signal rx_ctrl_out		: rx_ctrl_out_t;
 
 	signal rx_dout			: unsigned(31 downto 0);
-	signal rx_dout_vld		: std_logic;
+	signal rx_dout_re		: std_logic;
 	
 	signal rx_int_en		: std_logic;
 	signal tx_int_en		: std_logic;
@@ -64,24 +86,98 @@ ARCHITECTURE behavior OF emac_top_jb IS
 
 	signal ready			: std_logic;
 
+	signal read				: std_logic;
+	signal write			: std_logic;
+	signal rx_read_en_CPU	: std_logic;
+	signal rx_req_en_CPU	: std_logic;
+	signal rx_free_en_CPU	: std_logic;
+	signal tx_write_en_CPU	: std_logic;
+	signal reg_read			: std_logic;
+	signal reg_write		: std_logic;
+
+	signal reg_addr			: unsigned(3 downto 0);
+
+	-- DMA Controller
+	signal dma_master_req			: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_master_gnt			: unsigned(DMA_NUM_CHANNEL-1 downto 0) := (others => '0');
+	signal dma_req_rdy				: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_req_en				: unsigned(DMA_NUM_CHANNEL-1 downto 0) := (others => '0');
+	signal dma_req_addr_auto_inc	: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	type array32_t is array (0 to DMA_NUM_CHANNEL-1) of unsigned(31 downto 0);
+	signal dma_req_addr				: array32_t;
+	signal dma_req_num_xfers		: array32_t;
+
+	signal dma_req_complete			: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_req_complete_ack		: unsigned(DMA_NUM_CHANNEL-1 downto 0) := (others => '0');
+
+	signal dma_start					: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_active					: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_end						: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_bus_cmd_cycle_finished	: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_bus_cmd_cycle_en			: unsigned(DMA_NUM_CHANNEL-1 downto 0) := (others => '0');
+	signal dma_bus_cmd_rdy				: unsigned(DMA_NUM_CHANNEL-1 downto 0);
+	signal dma_bus_cmd_we				: unsigned(DMA_NUM_CHANNEL-1 downto 0) := (others => '0');
+	type array_bus_cmd_t is array (0 to DMA_NUM_CHANNEL-1) of bm_cmd_t;
+	signal dma_bus_cmd					: array_bus_cmd_t;
+
+	-- Busmaster arbiter
+	signal	arb_idx					: natural range 0 to DMA_NUM_CHANNEL-1;
+
+	-- BUS Master controller
+	signal bus_din_re				: std_logic;
+	signal bus_cmd_cycle_finished	: std_logic;
+	signal bus_cmd_cycle_en			: std_logic := '0';
+	signal bus_cmd_rdy				: std_logic;
+	signal bus_cmd_we				: std_logic := '0';
+	signal bus_cmd					: bm_cmd_t;
+	signal bus_din_rdy				: std_logic;
+	signal bus_din_vld				: std_logic := '0';
+	signal bus_din					: unsigned(31 downto 0) := (others => '-');
+	signal bus_dout					: unsigned(31 downto 0);
+	signal bus_dout_vld				: std_logic;
+	signal bus_dout_re				: std_logic := '0';
+	
 begin
 
-	SRDY_O				<= CYC_I and ready;
-	mii_gtx_clk			<= '0';
+	mii_gtx_clk				<= '0';
 
-	ready				<= not tx_ctrl_in.pkt_alloc_en;
+	SRDY_O					<= CYC_I and ready;
+	read					<= STB_I and CYC_I and not WE_I;
+	write					<= STB_I and CYC_I and WE_I;
+	rx_read_en_CPU			<= read and ADDR_I(15);
+	tx_write_en_CPU			<= write and ADDR_I(15);
+	reg_read				<= read and not ADDR_I(15);
+	reg_write				<= write and not ADDR_I(15);
+	reg_addr				<= ADDR_I(5 downto 2);
+
+	ready					<= not tx_ctrl_in.pkt_alloc_en;
+	
+	tx_din_vld				<= tx_write_en_CPU;
+	tx_din					<= DAT_I;
+
+	rx_ctrl_in.pkt_free_en	<= rx_free_en_CPU or dma_end(0);
+	rx_ctrl_in.pkt_req_en	<= rx_req_en_CPU or dma_start(0);
+
+	rx_dout_re				<= rx_read_en_CPU or (dma_active(DMA_CH_WRITE) and bus_din_rdy);
+	
+	bus_din					<= rx_dout;
+	bus_din_vld				<= dma_active(DMA_CH_WRITE);
+	dma_master_gnt(0)		<= SRDY_I;
+	dma_req_en(0)			<= rx_ctrl_out.pkt_avail;
+	dma_req_num_xfers(0)	<= X"0000" & "00" & rx_ctrl_out.rx_size(15 downto 2) when rx_ctrl_out.rx_size(1 downto 0) = "00" else X"0000" & "00" & rx_ctrl_out.rx_size(15 downto 2) + 1;
+	dma_req_addr(0)			<= X"00000800";
+	dma_req_addr_auto_inc	<= "11";
 	
 ------------------------------------------------------------------
 registers_write: 
 	process(CLK_I)
 	begin
 		if rising_edge(CLK_I) then
-			tx_din_vld					<= '0';
 			tx_ctrl_in.pkt_alloc_en		<= '0';
 			tx_ctrl_in.pkt_commit_en	<= '0';
 			tx_ctrl_in.reset			<= '0';
-			rx_ctrl_in.pkt_free_en		<= '0';
-			rx_ctrl_in.pkt_req_en		<= '0';
+			rx_free_en_CPU				<= '0';
+			rx_req_en_CPU				<= '0';
 			rx_ctrl_in.reset			<= '0';
 			if RST_I = '1' then
 				rx_int_en				<= '0';
@@ -93,22 +189,24 @@ registers_write:
 				rx_ctrl_in.Gbps_en		<= '0';
 				tx_ctrl_in.fcs_gen_en	<= '0';
 				rx_ctrl_in.fcs_chk_en	<= '0';
-			elsif (STB_I and CYC_I and WE_I) = '1' then
-				case ADDR_I(5 downto 2) is
-				
+			elsif reg_write = '1' then
+			
+				-- 0x0000 .. 0x003C
+				case reg_addr is
+
 				-- 0x0000
 				when "0000" =>
 					rx_ctrl_in.reset			<= DAT_I(31);
 					rx_ctrl_in.Gbps_en			<= DAT_I(30);
 					rx_ctrl_in.fcs_chk_en		<= DAT_I(29);
 					rx_ctrl_in.promiscious		<= DAT_I(23);
-					rx_ctrl_in.pkt_req_en		<= DAT_I(17);
-					rx_ctrl_in.pkt_free_en		<= DAT_I(16);
+					rx_req_en_CPU				<= DAT_I(17);
+					rx_free_en_CPU				<= DAT_I(16);
 					rx_int_en					<= DAT_I(4);
-					
+
 				-- 0x0004
 				-- rx_size R/O
-				
+
 				-- 0x0008
 				when "0010" =>
 					tx_ctrl_in.reset			<= DAT_I(31);
@@ -117,16 +215,14 @@ registers_write:
 					tx_ctrl_in.pkt_alloc_en		<= DAT_I(17);
 					tx_ctrl_in.pkt_commit_en	<= DAT_I(16);
 					tx_int_en					<= DAT_I(4);
-					
+
 				-- 0x000C
 				when "0011" => 
 					tx_ctrl_in.tx_size			<= DAT_I(15 downto 0);
-					
+
 				-- 0x0010
-				when "0100" =>
-					tx_din_vld					<= '1';
-					tx_din						<= DAT_I;
-					
+				-- Gap
+
 				-- 0x0014
 				-- Gap
 
@@ -136,14 +232,18 @@ registers_write:
 					rx_ctrl_in.mac_addr(1)		<= DAT_I(23 downto 16);
 					rx_ctrl_in.mac_addr(2)		<= DAT_I(15 downto 8);
 					rx_ctrl_in.mac_addr(3)		<= DAT_I(7 downto 0);
-					
+
 				-- 0x001C
 				when "0111" =>
 					rx_ctrl_in.mac_addr(4)		<= DAT_I(31 downto 24);
 					rx_ctrl_in.mac_addr(5)		<= DAT_I(23 downto 16);
 
+				-- 0x0020 .. 0x003C
+				-- Gap
 				when others => null;
+
 				end case;
+				
 			end if;	
 		end if;	
 	end process;
@@ -152,11 +252,12 @@ registers_read:
 	process(CLK_I)
 	begin
 		if rising_edge(CLK_I) then
-			rx_ctrl_in.pkt_read_en	<= '0';
-			ACK_O					<= rx_dout_vld and CYC_I and not WE_I;
+			ACK_O					<= rx_read_en_CPU;
 			DAT_O					<= rx_dout;
-			if (STB_I and CYC_I) = '1' and WE_I = '0' then
-				case ADDR_I(5 downto 2) is
+			if reg_read = '1' then
+				
+				-- 0x0000 .. 0x003C
+				case reg_addr is
 
 				-- 0x0000
 				when "0000" =>	
@@ -171,7 +272,7 @@ registers_read:
 					DAT_O(17)	<= rx_ctrl_out.pkt_valid;
 					DAT_O(16)	<= rx_ctrl_out.pkt_avail;
 					DAT_O(4)	<= rx_int_en;
-					
+
 				-- 0x0004
 				when "0001" => 
 					ACK_O		<= '1';
@@ -188,16 +289,15 @@ registers_read:
 					DAT_O(17)	<= tx_ctrl_out.pkt_alloc_req;
 					DAT_O(16)	<= tx_ctrl_out.pkt_armed;
 					DAT_O(4)	<= tx_int_en;
-					
+
 				-- 0x000C
 				when "0011" => 
 					ACK_O		<= '1';
 					DAT_O		<= X"0000" & tx_ctrl_out.tx_size;
 
 				-- 0x0010
-				when "0100" =>
-					rx_ctrl_in.pkt_read_en	<= '1';
-						
+				-- Gap
+
 				-- 0x0014
 				-- Gap
 
@@ -205,14 +305,18 @@ registers_read:
 				when "0110" =>
 					ACK_O		<= '1';
 					DAT_O		<= rx_ctrl_in.mac_addr(0) & rx_ctrl_in.mac_addr(1) & rx_ctrl_in.mac_addr(2) & rx_ctrl_in.mac_addr(3);
-	
+
 				-- 0x001C
 				when "0111" =>
 					ACK_O		<= '1';
 					DAT_O		<= rx_ctrl_in.mac_addr(4) & rx_ctrl_in.mac_addr(5) & X"0000";
-				
+
+				-- 0x0020 .. 0x003C
+				-- Gap
 				when others => null;
+
 				end case;
+
 			end if;
 		end if;	
 	end process;
@@ -237,7 +341,7 @@ inst_emac_rx : entity work.emac_rx
 	(
 		clk			=> CLK_I,
 		rst			=> RST_I,
-		dout_vld	=> rx_dout_vld,
+		dout_re		=> rx_dout_re,
 		dout		=> rx_dout,
 		ctrl_in		=> rx_ctrl_in,
 		ctrl_out	=> rx_ctrl_out,
@@ -272,5 +376,128 @@ inst_emac_tx : entity work.emac_tx
 		
 	);
 
+gen_dmac:
+for i in 0 to DMA_NUM_CHANNEL-1 generate
+	
+	dma_bus_cmd_cycle_finished(i)	<= bus_cmd_cycle_finished;
+	dma_bus_cmd_rdy(i) 				<= bus_cmd_rdy;
+
+	inst_dmac : entity work.dmac
+	Generic map
+	(
+		DATA_WIDTH			=> 32,
+		XFER_CHUNK_SIZE		=> 32
+	)
+	Port map
+	(
+		clk					=> CLK_I,
+		rst					=> RST_I,
+
+		master_req			=> dma_master_req(i),
+		master_gnt			=> dma_master_gnt(i),
+
+		req_rdy				=> dma_req_rdy(i),
+		req_en				=> dma_req_en(i),
+		req_rw				=> DMA_RW_CONF(i),
+		req_addr_auto_inc	=> dma_req_addr_auto_inc(i),
+		req_addr_start		=> dma_req_addr(i),
+		req_num_xfers		=> dma_req_num_xfers(i),
+
+		req_complete		=> dma_req_complete(i),
+		req_complete_ack	=> dma_req_complete_ack(i),
+
+		dma_start			=> dma_start(i),
+		dma_active			=> dma_active(i),
+		dma_end				=> dma_end(i),
+
+		-- busmaster control
+		bus_cyc_complete	=> dma_bus_cmd_cycle_finished(i),
+		bus_cmd_rdy			=> dma_bus_cmd_rdy(i),
+		bus_cmd_we			=> dma_bus_cmd_we(i),
+		bus_cmd_cycle_en	=> dma_bus_cmd_cycle_en(i),
+
+		-- busmaster command
+		bus_cmd_out			=> dma_bus_cmd(i)
+	);
+
+end generate;
+
+inst_busmaster_sync : entity work.busmaster_sync
+	GENERIC MAP
+	(
+		DATA_WIDTH					=> 32,
+		FIFO_DEPTH					=> 4
+	)
+	PORT MAP
+	(
+		-- System signals
+		rst					=> RST_I,
+		clk					=> CLK_I,
+
+		cmd_cycle_finished	=> bus_cmd_cycle_finished,
+		cmd_cycle_en		=> bus_cmd_cycle_en,
+		
+		cmd_rdy				=> bus_cmd_rdy,
+		cmd_we				=> bus_cmd_we,
+		cmd_in				=> bus_cmd,
+		
+		din_rdy				=> bus_din_rdy,
+		din_we				=> bus_din_vld,
+		din					=> bus_din,
+
+		dout				=> bus_dout,
+		dout_vld			=> bus_dout_vld,
+		dout_re				=> bus_dout_re,
+
+		-- JBUS Master signals
+		CYC_O				=> CYC_O,
+		STB_O				=> STB_O,
+		WE_O				=> WE_O,
+		SEL_O				=> SEL_O,
+		ACK_I				=> ACK_I,
+		SRDY_I				=> SRDY_I,
+		MRDY_O				=> MRDY_O,
+		ADDR_O				=> ADDR_O,
+		MDAT_I				=> MDAT_I,
+		MDAT_O				=> MDAT_O
+	);
+
+arbiter_proc:
+	process(CLK_I)
+	begin
+		if rising_edge(CLK_I) then
+			if RST_I = '1' then
+				dma_master_gnt	<= (others => '0');
+				arb_idx	<= 0;
+			elsif dma_master_req(arb_idx) = '0' then
+				if arb_idx /= DMA_NUM_CHANNEL-1 then
+					arb_idx	<= arb_idx + 1;
+				else
+					arb_idx	<= 0;
+				end if;
+			else	
+				dma_master_gnt	<= (others => '0');
+				dma_master_gnt(arb_idx)	<= '1';
+			end if;	
+		end if;
+	end process;
+
+arbiter_mux:
+	process(dma_master_gnt, dma_bus_cmd, dma_bus_cmd_we, dma_bus_cmd_cycle_en)
+	variable v_bus_cmd_we : std_logic;
+	variable v_bus_cmd_cycle_en : std_logic;
+	begin
+		v_bus_cmd_we := '0';
+		v_bus_cmd_cycle_en := '0';
+		for i in 0 to DMA_NUM_CHANNEL-1 loop
+			v_bus_cmd_we := v_bus_cmd_we or dma_bus_cmd_we(i);
+			v_bus_cmd_cycle_en := v_bus_cmd_cycle_en or dma_bus_cmd_cycle_en(i);
+			if dma_master_gnt(i) = '1' then
+				bus_cmd <= dma_bus_cmd(i);
+			end if;
+		end loop;
+		bus_cmd_we <= v_bus_cmd_we;
+		bus_cmd_cycle_en <= v_bus_cmd_cycle_en;
+end process;
 
 end behavior;

lib/emac/src/emac_tx.vhd

@@ -116,13 +116,9 @@ ARCHITECTURE behavior OF emac_tx IS
 	signal mii_fifo_re		: std_logic;
 	signal mii_fifo_full	: std_logic;
 	signal mii_fifo_empty	: std_logic;
-	signal mii_fifo_re_dly	: unsigned(7 downto 0);
+	signal mii_fifo_re_dly	: unsigned(23 downto 0);
 
-	subtype ifg_cnt_t is natural range 0 to 23;		-- 10/100 mbps
---	subtype ifg_cnt_t is natural range 0 to 11;		-- 1000 mbps
-
-	signal ifg_cnt			: ifg_cnt_t;
-	signal ifg_idle			: std_logic;
+	signal mii_bsy			: std_logic;
 
 	type host_state_t is (host_init, host_idle, host_alloc, host_setup, host_arm, host_fill, host_commit);
 	signal host_s, host_sn : host_state_t;
@@ -340,6 +336,7 @@ mem_free_counter:
 		end if;
 	end process;	
 
+------------------------------------------------------------------
 mem_free_mii:
 	process(mii_tx_clk)
 	begin
@@ -356,6 +353,7 @@ mem_free_mii:
 		end if;
 	end process;	
 
+------------------------------------------------------------------
 mem_free_host:
 	process(clk)
 	begin
@@ -373,15 +371,6 @@ mem_free_host:
 		end if;
 	end process;	
 
-host2xfer_sync_register:
-	process(mii_tx_clk)
-	begin
-		if rising_edge(mii_tx_clk) then
-			Gbps_en			<= ctrl_in.Gbps_en;
-			fcs_gen_en		<= ctrl_in.fcs_gen_en;
-		end if;	
-	end process;	
-
 ------------------------------------------------------------------
 -- Fill stuff
 ------------------------------------------------------------------
@@ -411,6 +400,7 @@ fill_counter:
 		end if;
 	end process;	
 
+------------------------------------------------------------------
 fill_pointer:
 	process(clk)
 	begin
@@ -426,20 +416,14 @@ fill_pointer:
 ------------------------------------------------------------------
 -- Transfer stuff
 ------------------------------------------------------------------
-interframe_gap_counter:
+host2xfer_sync_register:
 	process(mii_tx_clk)
 	begin
 		if rising_edge(mii_tx_clk) then
-			ifg_idle	<= '0';
-			if reset_en = '1' or mii_fifo_empty = '0' then
-				ifg_cnt 	<= ifg_cnt_t'high;
-			elsif ifg_cnt /= 0 then
-				ifg_cnt		<= ifg_cnt - 1;
-			else
-				ifg_idle	<= '1';
-			end if;
-		end if;
-	end process;
+			Gbps_en			<= ctrl_in.Gbps_en;
+			fcs_gen_en		<= ctrl_in.fcs_gen_en;
+		end if;	
+	end process;	
 
 ------------------------------------------------------------------
 xfer_counter:
@@ -465,6 +449,7 @@ xfer_counter:
 			
 	end process;	
 	
+------------------------------------------------------------------
 xfer_pointer:
 	process(mii_tx_clk)
 	begin
@@ -494,7 +479,7 @@ xfer_state_next:
 	end process;	
 
 xfer_state:
-	process(xfer_s, ifg_idle, cmd_fifo_empty, piso32_din_rdy, piso32_dout_vld, xfer_bsy, fcs_gen_en)
+	process(xfer_s, mii_bsy, cmd_fifo_empty, piso32_din_rdy, piso32_dout_vld, xfer_bsy, fcs_gen_en)
 	begin
 		
 		piso32_din_vld		<= '0';
@@ -515,12 +500,12 @@ xfer_state:
 			xfer_sn 		<= xfer_idle;
 			
 		when xfer_idle =>
-			if cmd_fifo_empty = '0' then
+			if cmd_fifo_empty = '0' and mii_bsy = '0' then
 				xfer_sn 		<= xfer_start;
 			end if;
 			
 		when xfer_start =>
-			if cmd_fifo_empty = '0' and ifg_idle = '1' then
+			if cmd_fifo_empty = '0' then
 				xfer_sn 		<= xfer_preamble0;
 			end if;
 
@@ -577,7 +562,7 @@ xfer_state:
 	end process;
 
 ------------------------------------------------------------------
-inst_ram : entity work.dpram_1w1r
+inst_ram : entity work.dpram_1w1r2c_ro
 	GENERIC MAP 
 	(
 		addr_width	=> RAM_ADDR_WIDTH,
@@ -585,8 +570,8 @@ inst_ram : entity work.dpram_1w1r
 	)
 	PORT MAP 
 	(
-		clka		=> clk,
-		clkb		=> mii_tx_clk,
+		clk_a		=> clk,
+		clk_b		=> mii_tx_clk,
 		en_a		=> ram_en_a,
 		en_b		=> ram_en_b,
 		we_a		=> ram_we_a,
@@ -596,6 +581,7 @@ inst_ram : entity work.dpram_1w1r
 		dout_b		=> ram_dout_b
 	);
 
+------------------------------------------------------------------
 -- Instantiate synchronous FIFO
 inst_cmd_fifo: entity work.fifo_async
 	GENERIC MAP
@@ -619,6 +605,7 @@ inst_cmd_fifo: entity work.fifo_async
 		data_r		=>  cmd_fifo_dout
 	);
 
+------------------------------------------------------------------
 inst_piso32 : entity work.piso
 	GENERIC MAP
 	(
@@ -642,6 +629,7 @@ inst_piso32 : entity work.piso
 
 	piso32_dout_en	<= not mii_fifo_full; --'1' when Gbps_en = '1' else piso8_din_rdy;
 	
+------------------------------------------------------------------
 fcs_enable_gen:
 	process(mii_tx_clk)
 	begin
@@ -653,8 +641,8 @@ fcs_enable_gen:
 			end if;
 		end if;
 	end process;	
-	fcs_din_vld	<= fcs_en(fcs_en'left) and piso32_dout_vld and piso32_dout_en;
-	
+
+------------------------------------------------------------------
 inst_fcs: entity work.crc32
 	GENERIC MAP
 	(
@@ -671,17 +659,29 @@ inst_fcs: entity work.crc32
 		
 	);
 
+	fcs_din_vld	<= fcs_en(fcs_en'left) and piso32_dout_vld and piso32_dout_en;
+
+------------------------------------------------------------------
+-- ensures continous MII-data stream and also acts as Inter Frame Gap delay
 mii_fifo_re_dly_gen:
 	process(mii_tx_clk)
 	begin
 		if rising_edge(mii_tx_clk) then
-			mii_fifo_re_dly	<= mii_fifo_re_dly(mii_fifo_re_dly'left-1 downto 0) & not mii_fifo_empty;
+			if mii_fifo_empty = '1' then
+				if Gbps_en = '0' then
+					mii_fifo_re_dly	<= X"000000";	-- 100 mbps
+				else
+					mii_fifo_re_dly	<= X"000FFF";	-- Gigabit
+				end if;
+			else
+				mii_fifo_re_dly	<= mii_fifo_re_dly(mii_fifo_re_dly'left-1 downto 0) & not mii_fifo_empty;
+			end if;
 		end if;
 	end process;	
 
-	mii_fifo_re		<= mii_fifo_re_dly(mii_fifo_re_dly'left) when Gbps_en = '1' else (piso8_din_rdy and mii_fifo_re_dly(mii_fifo_re_dly'left));
-	mii_fifo_we		<= piso32_dout_vld;
+	mii_bsy			<= mii_fifo_re_dly(mii_fifo_re_dly'left);
 	
+------------------------------------------------------------------
 -- Instantiate synchronous FIFO
 inst_mii_fifo: entity work.fifo_sync
 	GENERIC MAP
@@ -704,6 +704,10 @@ inst_mii_fifo: entity work.fifo_sync
 		data_r		=>  piso8_din
 	);
 	
+	mii_fifo_re		<= mii_bsy when Gbps_en = '1' else (piso8_din_rdy and mii_bsy);
+	mii_fifo_we		<= piso32_dout_vld;
+
+------------------------------------------------------------------
 inst_piso8 : entity work.piso
 	GENERIC MAP
 	(
@@ -724,8 +728,10 @@ inst_piso8 : entity work.piso
 		dout		=> piso8_dout
 		
 	);
-	piso8_din_vld	<= not mii_fifo_empty and mii_fifo_re_dly(mii_fifo_re_dly'left);
+
+	piso8_din_vld	<= not mii_fifo_empty and mii_bsy;
 	
+------------------------------------------------------------------
 mii_output_register:
 	process(mii_tx_clk)
 	begin
@@ -741,4 +747,5 @@ mii_output_register:
 		end if;	
 	end process;	
 
+------------------------------------------------------------------
 end behavior;

lib/emac/src/emac_types.vhd

@@ -36,7 +36,6 @@ package emac_types is
 		Gbps_en				: std_logic;
 		reset				: std_logic;
 		fcs_chk_en			: std_logic;
-		pkt_read_en			: std_logic;
 		pkt_req_en			: std_logic;
 		pkt_free_en			: std_logic;
 		mac_addr			: mac_addr_t;

lib/emac/src/tb_emac_top_jb.vhd

@@ -53,6 +53,18 @@ ARCHITECTURE behavior OF tb_emac_top_jb IS
 	signal status_reg		: unsigned(31 downto 0) := (others => '0');
 	signal size_reg			: unsigned(31 downto 0) := (others => '0');
 
+	-- Master
+	signal CYC_O					: std_logic;
+	signal STB_O					: std_logic;
+	signal WE_O						: std_logic;
+	signal SEL_O					: unsigned(3 downto 0) := (others => '1');
+	signal ACK_I					: std_logic := '0';
+	signal MRDY_O					: std_logic := '1';
+	signal SRDY_I					: std_logic := '1';
+	signal ADDR_O					: unsigned(31 downto 0) := (others => '-');
+	signal MDAT_I					: unsigned(31 downto 0) := (others => '-');
+	signal MDAT_O					: unsigned(31 downto 0) := (others => '-');
+
 	-- MII signals
 	signal mii_rx_clk_board	: std_logic := '1';
 	signal mii_tx_clk_board	: std_logic := '1';
@@ -88,10 +100,88 @@ ARCHITECTURE behavior OF tb_emac_top_jb IS
 	constant RX_SIZE_REG_ADDR	: unsigned(31 downto 0) := X"0000_0004";
 	constant TX_STATUS_REG_ADDR	: unsigned(31 downto 0) := X"0000_0008";
 	constant TX_SIZE_REG_ADDR	: unsigned(31 downto 0) := X"0000_000C";
-	constant DATA_REG_ADDR		: unsigned(31 downto 0) := X"0000_0010";
+	constant DATA_REG_ADDR		: unsigned(31 downto 0) := X"0000_8000";
 
+
+	-- 64Bit RAM
+	signal MDAT_I_64				: unsigned(63 downto 0) := (others => '-');
+	signal MDAT_O_64				: unsigned(63 downto 0) := (others => '-');
+
+	type ram_t  is array (0 to 511) of unsigned(63 downto 0);
+
+	signal ram64		: ram_t;
+
+	
 BEGIN
 
+	MDAT_I	<= MDAT_I_64(31 downto 0);
+	MDAT_O_64	<= MDAT_O & MDAT_O;
+
+	process(CLK)
+	variable res: unsigned(63 downto 0);
+	variable ram_data : unsigned(63 downto 0);
+	variable data8: unsigned(7 downto 0);
+	begin
+		if rising_edge(CLK) then
+			if RST = '1' then
+					data8 := X"00";
+				for i in 0 to 255 loop
+					ram_data(7 downto 0)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(15 downto 8)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(23 downto 16)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(31 downto 24)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(39 downto 32)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(47 downto 40)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(55 downto 48)	:= data8;
+					data8				:= data8 + 1;
+					ram_data(63 downto 56)	:= data8;
+					data8				:= data8 + 1;
+					ram64(i) <= ram_data;
+				end loop;
+			else
+				ACK_I	<= '0';
+				if (CYC_O and STB_O) = '1' then
+					if WE_O = '0' then
+						ACK_I	<= '1';
+						ram_data := ram64(to_integer(ADDR_O(31 downto 3)));
+						if ADDR_O(2) = '0' then
+							res			:= ram_data;
+						else
+							res			:= ram_data(31 downto 0) & ram_data(63 downto 32);
+						end if;
+					else -- WE=1
+						ram_data := ram64(to_integer(ADDR_O(31 downto 3)));
+					--	ram_data := (others => '-');
+						if ADDR_O(2) = '0' then
+							if SEL_O = "11111111" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= MDAT_O_64;
+							elsif SEL_O = "00001111" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= ram_data(63 downto 32) & MDAT_O_64(31 downto 0);
+							elsif SEL_O = "11110000" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= MDAT_O_64(63 downto 32) & ram_data(31 downto 0);
+							end if;
+						else
+							if SEL_O = "11111111" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= MDAT_O_64(31 downto 0) & MDAT_O_64(63 downto 32);
+							elsif SEL_O = "00001111" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= MDAT_O_64(31 downto 0) & ram_data(31 downto 0);
+							elsif SEL_O = "11110000" then
+								ram64(to_integer(ADDR_O(31 downto 3))) <= ram_data(63 downto 32) & MDAT_O_64(63 downto 32);
+							end if;
+						end if;
+					end if;
+				end if;
+				MDAT_I_64	<= res;
+			end if;
+		end if;
+	end process;
+
 inst_emac_top_jb : entity work.emac_top_jb
 	GENERIC MAP
 	(
@@ -101,6 +191,7 @@ inst_emac_top_jb : entity work.emac_top_jb
 	)
 	PORT MAP
 	(
+		-- JBUS Slave signals
 		CLK_I		=> CLK,
 		RST_I		=> RST,
 		INT_O		=> INT_O,
@@ -114,6 +205,19 @@ inst_emac_top_jb : entity work.emac_top_jb
 		ADDR_I		=> ADDR_I,
 		DAT_I		=> DAT_I,
 		DAT_O		=> DAT_O,
+		
+		-- JBUS Master signals
+		CYC_O		=> CYC_O,
+		STB_O		=> STB_O,
+		WE_O		=> WE_O,
+		SEL_O		=> SEL_O,
+		ACK_I		=> ACK_I,
+		SRDY_I		=> SRDY_I,
+		MRDY_O		=> MRDY_O,
+		ADDR_O		=> ADDR_O,
+		MDAT_I		=> MDAT_I,
+		MDAT_O		=> MDAT_O,
+		
 		mii_rx_clk	=> mii_rx_clk_board,
 		mii_rx_dv	=> mii_rx_dv,
 		mii_rx_er	=> mii_rx_er,
@@ -388,6 +492,7 @@ STIMULUS: process
 	variable size, num_words : natural;
 	begin
 
+		return;
 		emac_action	<= emac_wait_data;
 
 		-- check if data available
@@ -473,6 +578,7 @@ STIMULUS: process
 	procedure emac_free  is
 	begin
 	
+		return;
 		-- RX- DEALLOCATION
 		emac_action	<= emac_free;