Simulator compatibility updates

tests/conftest.py

@@ -1,7 +1,7 @@
 def pytest_addoption(parser):
     parser.addoption(
         "--sim-tool",
-        choices=["questa", "xilinx", "stub", "skip", "auto"],
+        choices=["questa", "xsim", "stub", "skip", "auto"],
         default="auto",
         help="""
         Select the simulator to use.
@@ -12,6 +12,29 @@ def pytest_addoption(parser):
         """
     )
 
+    parser.addoption(
+        "--gui",
+        default=False,
+        action="store_true",
+        help=""",
+        Launch sim tool in GUI mode
+
+        Only use this option when running a single test
+        """
+    )
+
+
+    parser.addoption(
+        "--rerun",
+        default=False,
+        action="store_true",
+        help=""",
+        Re-run simulation in-place without re-exporting regblock
+
+        Useful if hand-editing a testcase interactively.
+        """
+    )
+
     parser.addoption(
         "--synth-tool",
         choices=["vivado", "skip", "auto"],

tests/lib/base_testcase.py

@@ -49,6 +49,13 @@ class BaseTestCase(unittest.TestCase):
     def _load_request(self, request):
         self.request = request
 
+    @property
+    def rerun(self) -> bool:
+        """
+        Re-run wothout deleting and re-generating prior output directory.
+        """
+        return self.request.config.getoption("--rerun")
+
     def get_testcase_dir(self) -> str:
         class_dir = os.path.dirname(inspect.getfile(self.__class__))
         return class_dir
@@ -114,6 +121,9 @@ def _export_regblock(self):
         )
 
     def setUp(self) -> None:
+        if self.rerun:
+            return
+
         # Create fresh build dir
         run_dir = self.get_run_dir()
         if os.path.exists(run_dir):

tests/lib/cpuifs/axi4lite/axi4lite_intf_driver.sv

@@ -95,79 +95,148 @@ interface axi4lite_intf_driver #(
         @cb;
     end
 
-    semaphore txn_aw_mutex = new(1);
-    semaphore txn_w_mutex = new(1);
-    semaphore txn_b_mutex = new(1);
-    semaphore txn_ar_mutex = new(1);
-    semaphore txn_r_mutex = new(1);
+    //--------------------------------------------------------------------------
+    typedef struct {
+        logic [1:0] bresp;
+    } write_response_t;
+
+    class write_request_t;
+        mailbox #(write_response_t) response_mbx;
+        logic [ADDR_WIDTH-1:0] addr;
+        logic [DATA_WIDTH-1:0] data;
+        logic [DATA_WIDTH/8-1:0] strb;
+        function new();
+            this.response_mbx = new();
+        endfunction
+    endclass
+
+    mailbox #(write_request_t) aw_mbx = new();
+    mailbox #(write_request_t) w_mbx = new();
+    write_request_t write_queue[$];
+
+    // Issue AW transfers
+    initial forever begin
+        write_request_t req;
+        aw_mbx.get(req);
+        ##0;
+        repeat($urandom_range(2,0)) @cb;
+        cb.AWVALID <= '1;
+        cb.AWADDR <= req.addr;
+        cb.AWPROT <= '0;
+        @(cb);
+        while(cb.AWREADY !== 1'b1) @(cb);
+        cb.AWVALID <= '0;
+    end
+
+    // Issue W transfers
+    initial forever begin
+        write_request_t req;
+        w_mbx.get(req);
+        ##0;
+        repeat($urandom_range(2,0)) @cb;
+        cb.WVALID <= '1;
+        cb.WDATA <= req.data;
+        cb.WSTRB <= req.strb;
+        @(cb);
+        while(cb.WREADY !== 1'b1) @(cb);
+        cb.WVALID <= '0;
+        cb.WSTRB <= '0;
+    end
+
+    // Listen for R responses
+    initial forever begin
+        @cb;
+        while(rst || !(cb.BREADY === 1'b1 && cb.BVALID === 1'b1)) @cb;
+        if(write_queue.size() != 0) begin
+            // Can match this response with an existing request.
+            // Send response to requestor
+            write_request_t req;
+            write_response_t resp;
+            req = write_queue.pop_front();
+            resp.bresp = cb.BRESP;
+            req.response_mbx.put(resp);
+        end else begin
+            $error("Got unmatched write response");
+        end
+    end
 
     task automatic write(logic [ADDR_WIDTH-1:0] addr, logic [DATA_WIDTH-1:0] data, logic [DATA_WIDTH/8-1:0] strb = '1);
-        bit w_before_aw;
-        w_before_aw = $urandom_range(1,0);
-
-        fork
-            begin
-                txn_aw_mutex.get();
-                ##0;
-                if(w_before_aw) repeat($urandom_range(2,0)) @cb;
-                cb.AWVALID <= '1;
-                cb.AWADDR <= addr;
-                cb.AWPROT <= '0;
-                @(cb);
-                while(cb.AWREADY !== 1'b1) @(cb);
-                cb.AWVALID <= '0;
-                txn_aw_mutex.put();
-            end
-
-            begin
-                txn_w_mutex.get();
-                ##0;
-                if(!w_before_aw) repeat($urandom_range(2,0)) @cb;
-                cb.WVALID <= '1;
-                cb.WDATA <= data;
-                cb.WSTRB <= strb;
-                @(cb);
-                while(cb.WREADY !== 1'b1) @(cb);
-                cb.WVALID <= '0;
-                cb.WSTRB <= '0;
-                txn_w_mutex.put();
-            end
-
-            begin
-                txn_b_mutex.get();
-                @cb;
-                while(!(cb.BREADY === 1'b1 && cb.BVALID === 1'b1)) @(cb);
-                assert(!$isunknown(cb.BRESP)) else $error("Read from 0x%0x returned X's on BRESP", addr);
-                txn_b_mutex.put();
-            end
-        join
+        write_request_t req;
+        write_response_t resp;
+
+        req = new();
+        req.addr = addr;
+        req.data = data;
+        req.strb = strb;
+
+        aw_mbx.put(req);
+        w_mbx.put(req);
+        write_queue.push_back(req);
+
+        // Wait for response
+        req.response_mbx.get(resp);
+        assert(!$isunknown(resp.bresp)) else $error("Read from 0x%0x returned X's on BRESP", addr);
     endtask
 
+    //--------------------------------------------------------------------------
+    typedef struct {
+        logic [DATA_WIDTH-1: 0] rdata;
+        logic [1:0] rresp;
+    } read_response_t;
+
+    class read_request_t;
+        mailbox #(read_response_t) response_mbx;
+        function new();
+            this.response_mbx = new();
+        endfunction
+    endclass
+
+    semaphore txn_ar_mutex = new(1);
+    read_request_t read_queue[$];
+
+    // Listen for R responses
+    initial forever begin
+        @cb;
+        while(rst || !(cb.RREADY === 1'b1 && cb.RVALID === 1'b1)) @cb;
+        if(read_queue.size() != 0) begin
+            // Can match this response with an existing request.
+            // Send response to requestor
+            read_request_t req;
+            read_response_t resp;
+            req = read_queue.pop_front();
+            resp.rdata = cb.RDATA;
+            resp.rresp = cb.RRESP;
+            req.response_mbx.put(resp);
+        end else begin
+            $error("Got unmatched read response");
+        end
+    end
+
     task automatic read(logic [ADDR_WIDTH-1:0] addr, output logic [DATA_WIDTH-1:0] data);
+        read_request_t req;
+        read_response_t resp;
+
+        txn_ar_mutex.get();
+        // Issue read request
+        ##0;
+        cb.ARVALID <= '1;
+        cb.ARADDR <= addr;
+        cb.ARPROT <= '0;
+        @(cb);
+        while(cb.ARREADY !== 1'b1) @(cb);
+        cb.ARVALID <= '0;
+
+        // Push new request into queue
+        req = new();
+        read_queue.push_back(req);
+        txn_ar_mutex.put();
+
+        // Wait for response
+        req.response_mbx.get(resp);
 
-        fork
-            begin
-                txn_ar_mutex.get();
-                ##0;
-                cb.ARVALID <= '1;
-                cb.ARADDR <= addr;
-                cb.ARPROT <= '0;
-                @(cb);
-                while(cb.ARREADY !== 1'b1) @(cb);
-                cb.ARVALID <= '0;
-                txn_ar_mutex.put();
-            end
-
-            begin
-                txn_r_mutex.get();
-                @cb;
-                while(!(cb.RREADY === 1'b1 && cb.RVALID === 1'b1)) @(cb);
-                assert(!$isunknown(cb.RDATA)) else $error("Read from 0x%0x returned X's on RDATA", addr);
-                assert(!$isunknown(cb.RRESP)) else $error("Read from 0x%0x returned X's on RRESP", addr);
-                data = cb.RDATA;
-                txn_r_mutex.put();
-            end
-        join
+        assert(!$isunknown(resp.rdata)) else $error("Read from 0x%0x returned X's on RDATA", addr);
+        assert(!$isunknown(resp.rresp)) else $error("Read from 0x%0x returned X's on RRESP", addr);
+        data = resp.rdata;
     endtask
 
     task automatic assert_read(logic [ADDR_WIDTH-1:0] addr, logic [DATA_WIDTH-1:0] expected_data, logic [DATA_WIDTH-1:0] mask = '1);
@@ -177,6 +246,7 @@ interface axi4lite_intf_driver #(
         assert(data == expected_data) else $error("Read from 0x%x returned 0x%x. Expected 0x%x", addr, data, expected_data);
     endtask
 
+    //--------------------------------------------------------------------------
     initial begin
         reset();
     end

tests/lib/external_block.sv

@@ -14,7 +14,7 @@ module external_block #(
     output logic [WIDTH-1:0] rd_data,
     output logic wr_ack
 );
-timeunit 1ns;
+timeunit 1ps;
 timeprecision 1ps;
 
 localparam ADDR_SHIFT = $clog2(WIDTH/8);

tests/lib/external_reg.sv

@@ -13,7 +13,7 @@ module external_reg #(
     output logic [WIDTH-1:0] rd_data,
     output logic wr_ack
 );
-timeunit 1ns;
+timeunit 1ps;
 timeprecision 1ps;
 logic [SUBWORDS-1:0][WIDTH-1:0] value;
 
@@ -69,6 +69,7 @@ initial begin
         #1ns;
 
         if(!rst && req) begin
+            $info("got request");
             if(req_is_wr) do_write(req, wr_data, wr_biten);
             else do_read(req);
         end

tests/lib/sim_testcase.py

@@ -76,7 +76,8 @@ def setUp(self):
         super().setUp()
 
         # Create testbench from template
-        self._generate_tb()
+        if not self.rerun:
+            self._generate_tb()
 
         simulator = simulator_cls(self)
 

tests/lib/simulators/__init__.py

@@ -3,13 +3,13 @@
 
 from .base import Simulator
 from .questa import Questa
-from .xilinx import Xilinx
+from .xilinx import XilinxXSIM
 from .stub import StubSimulator
 
 ALL_SIMULATORS: List[Simulator]
 ALL_SIMULATORS = [
     Questa,
-    Xilinx,
+    XilinxXSIM,
     StubSimulator,
 ]
 

tests/lib/simulators/base.py

@@ -13,6 +13,10 @@ def is_installed(cls) -> bool:
     def __init__(self, testcase: 'SimTestCase' = None) -> None:
         self.testcase = testcase
 
+    @property
+    def gui_mode(self) -> bool:
+        return self.testcase.request.config.getoption("--gui")
+
     @property
     def tb_files(self) -> List[str]:
         files = []

tests/lib/simulators/questa.py

@@ -48,14 +48,21 @@ def run(self, plusargs:List[str] = None) -> None:
             "vsim", "-quiet",
             "-voptargs=+acc",
             "-msgmode", "both",
-            "-do", "set WildcardFilter [lsearch -not -all -inline $WildcardFilter Memory]",
-            "-do", "log -r /*;",
-            "-do", "run -all; exit;",
-            "-c",
             "-l", "%s.log" % test_name,
             "-wlf", "%s.wlf" % test_name,
             "tb",
+            "-do", "set WildcardFilter [lsearch -not -all -inline $WildcardFilter Memory]",
+            "-do", "log -r /*;",
         ]
+
+        if self.gui_mode:
+            cmd.append("-i")
+        else:
+            cmd.extend([
+                "-do", "run -all; exit;",
+                "-c",
+            ])
+
         for plusarg in plusargs:
             cmd.append("+" + plusarg)
         subprocess.run(cmd, check=True)