fix, needs polishing

Author: Aaron-Hartwig

hdl/ip/bsv/I2C/I2CBitController.bsv

@@ -155,14 +155,14 @@ module mkI2CBitController #(
     // After the delay we know SCL is being stretched if we aren't the ones
     // holding it low.
     (* fire_when_enabled *)
-    rule do_sample_scl_stretch(scl_stretch_sample_strobe && scl_in == 0 && state != AwaitStart);
-        scl_stretching              <= scl_out_en == 0;
+    rule do_sample_scl_stretch(scl_stretch_sample_strobe);
+        scl_stretching              <= scl_out_en == 0 && scl_in == 0;
         scl_stretch_sample_delay    <= False;
     endrule
 
     // If SCL is high then no one is holding it
     (* fire_when_enabled *)
-    rule do_clear_scl_stretch(scl_in == 1 || state == AwaitStart);
+    rule do_clear_scl_stretch(scl_in == 1 && !scl_stretch_sample_strobe);
         scl_stretching <= False;
     endrule
 

hdl/projects/sidecar/qsfp_x32/QSFPModule/test/QsfpModuleControllerTests.bsv

@@ -130,9 +130,9 @@ module mkBench (Bench);
 
     // Connect I2C busses since TriStates cannot be simulated
     mkConnection(controller.pins.scl.out, periph.scl_i);
-    mkConnection(controller.pins.scl.in, periph.scl_o);
+    mkConnection(periph.scl_o, controller.pins.scl.in);
     mkConnection(controller.pins.sda.out, periph.sda_i);
-    mkConnection(controller.pins.sda.in, periph.sda_o);
+    mkConnection(periph.sda_o, controller.pins.sda.in);
 
     // We need the ability to simulate the bus losing its pull-ups when a module has not been
     // inserted since that is how the design behaves. We only apply power to the module (and by the
@@ -745,4 +745,44 @@ module mkI2CSclStretchTimeoutTest (Empty);
     endseq);
 endmodule
 
+// mkUninitializationAfterRemovalTest
+//
+// This test ensures that a previously initialized module is uninitialized when
+// the module is removed regardless of `ResetL`'s status. That way when it is
+// reinserted, the initialization process happens again.
+module mkSclStretchTimeoutAfterRemovalAndReinsertionTest (Empty);
+    Bench bench <- mkBench();
+
+    Command read_cmd = Command {
+        op: Read,
+        i2c_addr: i2c_test_params.peripheral_addr,
+        reg_addr: 8'h00,
+        num_bytes: 1
+    };
+
+    mkAutoFSM(seq
+        add_and_initialize_module(bench);
+        bench.command(read_cmd, False, False);
+        await(!bench.i2c_busy());
+        assert_eq(unpack(bench.registers.port_status.error[2:0]),
+            NoError,
+            "NoError should be present when attempting to communicate after t_init has elapsed.");
+
+        remove_and_power_down_module(bench);
+
+
+        insert_and_power_module(bench);
+
+        bench.command(read_cmd, False, False);
+        await(!bench.i2c_busy());
+        delay(3);
+        assert_eq(unpack(bench.registers.port_status.error[2:0]),
+            NotInitialized,
+            "NotInitialized error should be present when a module has been reseated but not initialized.");
+        assert_eq(unpack(bench.registers.port_status.stretching_seen),
+            False,
+            "Should not have observed and SCL stretching.");
+    endseq);
+endmodule
+
 endpackage: QsfpModuleControllerTests

hdl/projects/sidecar/qsfp_x32/QSFPModule/test/QsfpModuleControllerTests.gtkw

@@ -1,19 +1,19 @@
 [*]
 [*] GTKWave Analyzer v3.3.104 (w)1999-2020 BSI
-[*] Thu Dec  5 13:08:47 2024
+[*] Thu Dec  5 20:23:37 2024
 [*]
 [dumpfile] "/home/aaron/Oxide/git/quartz/build/vcd/QsfpModuleControllerTests_mkUninitializationAfterRemovalTest.vcd"
-[dumpfile_mtime] "Thu Dec  5 13:00:44 2024"
+[dumpfile_mtime] "Thu Dec  5 19:45:50 2024"
 [dumpfile_size] 93767403
 [savefile] "/home/aaron/Oxide/git/quartz/hdl/projects/sidecar/qsfp_x32/QSFPModule/test/QsfpModuleControllerTests.gtkw"
-[timestart] 13499672
+[timestart] 8598640
 [size] 2592 1283
 [pos] -1 -1
-*-7.171101 13500140 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
+*-11.242826 8530010 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
 [treeopen] main.
 [treeopen] main.top.
-[sst_width] 596
-[signals_width] 645
+[sst_width] 445
+[signals_width] 603
 [sst_expanded] 1
 [sst_vpaned_height] 404
 @200
@@ -28,6 +28,7 @@ main.top.bench_modprsl_r
 @28
 main.top.bench_controller_hot_swap_enabled_r
 main.top.bench_hsc_pg_r
+main.top.bench_controller_power_good__output_r
 @200
 -
 -State
@@ -50,8 +51,12 @@ main.top.bench_controller_wdata_fifo_deq
 -
 -I2CCore
 @28
+main.top.bench_controller_i2c_core_bit_ctrl_sda_out_en
+main.top.bench_controller_i2c_core_bit_ctrl_scl_out_en
 main.top.bench_controller_i2c_core_bit_ctrl_sda_in
 main.top.bench_controller_i2c_core_bit_ctrl_scl_in
+@25
+main.top.bench_controller_i2c_core_bit_ctrl_state[2:0]
 @22
 main.top.bench_controller_i2c_core_state_r[3:0]
 @28
@@ -66,7 +71,7 @@ main.top.bench_periph_scl_stretch_countdown_q
 main.top.bench_controller_i2c_core_bit_ctrl_scl_stretch_timeout_cntr_count[15:0]
 @28
 main.top.bench_controller_i2c_core_bit_ctrl_scl_stretch_timeout_cntr_q
-@25
+@24
 main.top.bench_controller_i2c_core_bit_ctrl_scl_stretch_sample_strobe_count[5:0]
 @28
 main.top.bench_controller_i2c_core_bit_ctrl_scl_stretch_sample_strobe_q