Fix retirement + counter layouts

coreblocks/params/layouts.py

@@ -594,3 +594,8 @@ def __init__(self, gen_params: GenParams):
         ]
 
         self.report = self.get
+
+
+class CoreInstructionCounterLayouts:
+    def __init__(self, gen_params: GenParams):
+        self.decrement = [("empty", 1)]

coreblocks/stages/retirement.py

@@ -54,6 +54,7 @@ def elaborate(self, platform):
 
         fields = self.gen_params.get(CommonLayoutFields)
         m.submodules.frat_fix = frat_fix = Forwarder([fields.rl_dst, fields.rp_dst])
+        m.submodules.fetch_continue_fwd = fetch_continue_fwd = Forwarder([fields.pc])
 
         with Transaction().body(m):
             # TODO: do we prefer single precommit call per instruction?
@@ -108,13 +109,17 @@ def elaborate(self, platform):
                 # Resume core operation from exception handler
 
                 # mtvec without mode is [mxlen-1:2], mode is two last bits. Only direct mode is supported
-                resume_pc = m_csr.mtvec.value & ~(0b11)
-                self.fetch_continue(m, {"from_pc": 0, "next_pc": resume_pc})  # TODO: add from_pc valid
+                resume_pc = m_csr.mtvec.read(m) & ~(0b11)
+                fetch_continue_fwd.write(m, pc=resume_pc)
 
                 m.d.sync += side_fx.eq(1)
 
         with Transaction().body(m):
             data = frat_fix.read(m)
             self.rename(m, rl_s1=0, rl_s2=0, rl_dst=data["rl_dst"], rp_dst=data["rp_dst"])
 
+        with Transaction().body(m):
+            pc = fetch_continue_fwd.read(m).pc
+            self.fetch_continue(m, from_pc=0, next_pc=pc, resume_from_exception=1)
+
         return m

coreblocks/structs_common/instr_counter.py

@@ -1,13 +1,18 @@
 from amaranth import *
 from coreblocks.params.genparams import GenParams
-from coreblocks.params.layouts import FetchLayouts
+from coreblocks.params.layouts import CoreInstructionCounterLayouts, FetchLayouts
 from transactron.core import Method, TModule, def_method
 
 
 class CoreInstructionCounter(Elaboratable):
+    """
+    Counts instructions currently processed in core.
+    Used in exception handling, to wait for core flush to finsh.
+    """
+
     def __init__(self, gp: GenParams):
         self.increment = Method(i=gp.get(FetchLayouts).raw_instr)
-        self.decrement = Method(o=[("empty", 1)])
+        self.decrement = Method(o=gp.get(CoreInstructionCounterLayouts).decrement)
 
         self.count = Signal(gp.rob_entries_bits + 1)
 

test/stages/test_retirement.py

@@ -1,4 +1,4 @@
-from coreblocks.params.layouts import ExceptionRegisterLayouts
+from coreblocks.params.layouts import CoreInstructionCounterLayouts, ExceptionRegisterLayouts, FetchLayouts
 from coreblocks.stages.retirement import *
 from coreblocks.structs_common.csr_generic import GenericCSRRegisters
 
@@ -24,6 +24,8 @@ def elaborate(self, platform):
         lsu_layouts = self.gen_params.get(LSULayouts)
         scheduler_layouts = self.gen_params.get(SchedulerLayouts)
         exception_layouts = self.gen_params.get(ExceptionRegisterLayouts)
+        fetch_layouts = self.gen_params.get(FetchLayouts)
+        core_instr_counter_layouts = self.gen_params.get(CoreInstructionCounterLayouts)
 
         m.submodules.r_rat = self.rat = RRAT(gen_params=self.gen_params)
         m.submodules.f_rat = self.frat = FRAT(gen_params=self.gen_params)
@@ -43,6 +45,14 @@ def elaborate(self, platform):
         m.submodules.generic_csr = self.generic_csr = GenericCSRRegisters(self.gen_params)
         self.gen_params.get(DependencyManager).add_dependency(GenericCSRRegistersKey(), self.generic_csr)
 
+        m.submodules.mock_fetch_stall = self.mock_fetch_stall = TestbenchIO(Adapter())
+        m.submodules.mock_fetch_continue = self.mock_fetch_continue = TestbenchIO(
+            Adapter(i=fetch_layouts.branch_verify)
+        )
+        m.submodules.mock_instr_decrement = self.mock_instr_decrement = TestbenchIO(
+            Adapter(o=core_instr_counter_layouts.decrement)
+        )
+
         m.submodules.retirement = self.retirement = Retirement(
             self.gen_params,
             rob_retire=self.mock_rob_retire.adapter.iface,
@@ -53,6 +63,9 @@ def elaborate(self, platform):
             precommit=self.mock_precommit.adapter.iface,
             exception_cause_get=self.mock_exception_cause.adapter.iface,
             frat_rename=self.frat.rename,
+            fetch_stall=self.mock_fetch_stall.adapter.iface,
+            fetch_continue=self.mock_fetch_continue.adapter.iface,
+            instr_decrement=self.mock_instr_decrement.adapter.iface,
         )
 
         m.submodules.free_rf_fifo_adapter = self.free_rf_adapter = TestbenchIO(AdapterTrans(self.free_rf.read))
@@ -93,6 +106,8 @@ def setUp(self):
     def test_rand(self):
         retc = RetirementTestCircuit(self.gen_params)
 
+        yield from retc.mock_fetch_stall.enable()
+
         @def_method_mock(lambda: retc.mock_rob_retire, enable=lambda: bool(self.submit_q), sched_prio=1)
         def retire_process():
             return self.submit_q.popleft()