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diff --git a/testsuite/gna/bug10/TestFIFO.vhdl b/testsuite/gna/bug10/TestFIFO.vhdl
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+library IEEE;
+use IEEE.std_logic_1164.all;
+use IEEE.numeric_std.all;
+
+-- equal speed writer and reader
+-- faster writer
+-- faster reader
+
+entity TestFIFO is
+end TestFIFO;
+
+
+architecture behaviour of TestFIFO is
+
+ component FIFO is
+ generic(Depth : integer := 3);
+ port(
+ iClk : in std_logic;
+ iReset : in std_logic;
+ -- write port
+ iWrEn : in std_logic;
+ iData : in std_logic_vector(7 downto 0);
+ oHasSpace : out std_logic;
+ -- read port
+ iRdEn : in std_logic;
+ oData : out std_logic_vector(7 downto 0);
+ oHasData : out std_logic
+ );
+ end component;
+
+ type ramType is array(0 to 255) of std_logic_vector(7 downto 0);
+
+ signal clk, reset : std_logic;
+ signal wrEn, rdEn : std_logic;
+ signal inData, outData : std_logic_vector(7 downto 0);
+ signal hasSpace, hasData : std_logic;
+
+ signal rawInData : std_logic_vector(7 downto 0);
+ signal rawWrEn, rawRdEn : std_logic;
+
+ signal dstRAM : ramType;
+
+ signal writerData : unsigned(8 downto 0) := (others => '0');
+ signal writerWrEn : std_logic;
+ signal writeDone : std_logic;
+ signal writerClkCntInit, readerClkCntInit : unsigned(1 downto 0) := "00";
+ signal writerClkCnt, readerClkCnt : unsigned(1 downto 0) := "00";
+
+ signal readerCnt : unsigned(8 downto 0) := (others => '0');
+ signal readerRdEn : std_logic;
+ signal readDone : std_logic;
+
+ signal rawMode : std_logic;
+
+
+begin
+
+ FIFO0: FIFO port map(
+ iClk => clk, iReset => reset,
+ iWrEn => wrEn, iData => inData, oHasSpace => hasSpace,
+ iRdEn => rdEn, oData => outData, oHasData => hasData
+ );
+
+ wrEn <= rawWrEn when rawMode = '1' else writerWrEn;
+ rdEn <= rawRdEn when rawMode = '1' else readerRdEn;
+
+ inData <= rawInData when rawMode = '1' else std_logic_vector(writerData(7 downto 0));
+ writeDone <= writerData(7); -- done when writerData == 0x100
+ writerWrEn <= '1' when (writerClkCnt = "00") and (hasSpace = '1') and (writeDone = '0') else '0';
+
+ fifoWriter: process(clk)
+ begin
+ if clk'event and clk = '1' and reset = '0' then
+ if writerClkCnt = "00" then
+ if hasSpace = '1' and writeDone = '0' then
+ writerData <= writerData + 1;
+ end if;
+ report "writerClkCnt <= writerClkCntInit;";
+ writerClkCnt <= writerClkCntInit;
+ else
+ report "writerClkCnt <= writerClkCnt - 1;";
+ writerClkCnt <= writerClkCnt - 1;
+ end if;
+ end if;
+ end process;
+
+ readDone <= readerCnt(7); -- done when readerCnt == 0x100
+ readerRdEn <= '1' when readerClkCnt = "00" and hasData = '1' and readDone = '0' else '0';
+
+ fifoReader: process(clk)
+ begin
+ if clk'event and clk = '1' and reset = '0' then
+ if readerClkCnt = "00" then
+ if hasData = '1' and readDone = '0' then
+ dstRAM(to_integer(readerCnt)) <= outData;
+ readerCnt <= readerCnt + 1;
+ end if;
+ readerClkCnt <= readerClkCntInit;
+ else
+ readerClkCnt <= readerClkCnt - 1;
+ end if;
+ end if;
+ end process;
+
+ main: process
+
+ procedure nextCycle is begin
+ wait for 500 ns;
+ report "rise";
+ clk <= '1';
+ wait for 500 ns;
+ clk <= '0';
+ end procedure;
+
+ procedure doReset is begin
+ reset <= '1';
+ clk <= '0';
+ nextCycle;
+ reset <= '0';
+ end procedure;
+
+ procedure testSimple is
+
+ procedure write(data : std_logic_vector(7 downto 0); expHasData, expHasSpace: std_logic) is begin
+ rawWrEn <= '1';
+ rawInData <= data;
+ nextCycle;
+ assert hasData = expHasData and hasSpace = expHasSpace;
+ end procedure;
+
+ begin
+ rawMode <= '1';
+ rawWrEn <= '0';
+ rawRdEn <= '0';
+ doReset;
+ assert hasData = '0' and hasSpace = '1';
+ write(X"70", '1', '1');
+ write(X"61", '1', '1');
+ write(X"52", '1', '1');
+ write(X"43", '1', '1');
+ write(X"34", '1', '1');
+ write(X"25", '1', '1');
+ write(X"16", '1', '1');
+ write(X"07", '1', '0');
+ write(X"5a", '1', '0'); -- attempt to write to the full FIFO, should be ignored
+ end procedure;
+
+ procedure clearDst is
+ variable i : integer;
+ begin
+ for i in 0 to 255 loop
+ dstRAM(i) <= X"00";
+ end loop;
+ end procedure;
+
+ procedure checkDst is
+ variable i : integer;
+ begin
+ for i in 0 to 255 loop
+ assert dstRAM(i) = std_logic_vector(to_unsigned(i, 8));
+ end loop;
+ end procedure;
+
+ -- 0 means fastest
+ procedure setWriterSpeed(div: integer) is begin
+ writerClkCntInit <= to_unsigned(div, 2);
+ writerClkCnt <= to_unsigned(div, 2);
+ writerData <= (others => '0');
+ end procedure;
+
+ procedure setReaderSpeed(div: integer) is begin
+ readerClkCntInit <= to_unsigned(div, 2);
+ readerClkCnt <= to_unsigned(div, 2);
+ end procedure;
+
+ procedure testEqualFastSpeed is begin
+ setWriterSpeed(0);
+ setReaderSpeed(0);
+ clearDst;
+ doReset;
+ while readDone = '0' loop
+ nextCycle;
+ end loop;
+ checkDst;
+ end procedure;
+
+ begin
+ testSimple;
+ -- testEqualFastSpeed;
+ wait; -- wait forever, end simulation
+ end process;
+
+end behaviour;