Merge pull request #58 from sarchlab/codex/shared-memory-banked-ld-st

Codex/shared memory banked ld st

Author: n0thingNoob

.gitignore

@@ -23,6 +23,22 @@ output/
 
 # logs
 *.log
+*.json.log
+
+# generated reports and traces
+*.report.json
+tmp-generated-*
+**/collected_reports*/
+**/sweep_reports*/
+**/sweep_reports_micro*/
+latest_collected_reports
+
+# local build artifacts
+/main
+
+# Python caches
+__pycache__/
+*.pyc
 
 .venv/
-venv/
+venv/

README.md

@@ -48,6 +48,7 @@ go run ./verify/cmd/verify-histogram     # outputs histogram_verification_report
 ## Architecture (How it fits together)
 - **Tile/Core** (`core/`): Instruction emulator + cycle-accurate send/recv paths on Akita ports; traces dataflow/memory events. Opcodes implemented in `core/emu.go`, state in `core/core.go`.
 - **CGRA device** (`cgra/`, `config/`): Mesh wiring of tiles; configurable memory mode (`simple`, `shared`, `local`) via `config.DeviceBuilder`. Uses Akita direct connections and optional shared memory controllers.
+- **Shared SRAM** (`config/`, `core/`): `memory_mode: "shared"` with `shared_memory_model: "banked"` models a shared SRAM scratchpad with per-bank conflict timing for compiler-style blocking `LOAD`/`STORE`; see `docs/shared-memory.md`.
 - **Driver** (`api/driver.go`): Maps per-PE kernels, feeds inputs, collects outputs, and ticks the simulation engine. Supports preload/read of per-PE memory.
 - **Verification fast path** (`verify/`): Static lint (STRUCT/TIMING) + functional simulator + report generator. Mirrors opcode semantics without timing/backpressure; CLIs in `verify/cmd/`.
 - **Testbench** (`test/Zeonica_Testbench` submodule): Reference kernels (AXPY, histogram, etc.) consumed by verify and simulation tests.
@@ -81,4 +82,4 @@ flowchart LR
 - If adding opcodes, update `core/emu.go` and `verify/funcsim.go`, plus unit tests in `verify/`.
 
 ## License
-See `LICENSE` for details.
+See `LICENSE` for details.

api/builder.go

@@ -3,16 +3,28 @@ package api
 import "github.com/sarchlab/akita/v4/sim"
 
 type defaultPortFactory struct {
+	incomingBufCap int
+	outgoingBufCap int
 }
 
 func (f defaultPortFactory) make(c sim.Component, name string) sim.Port {
-	return sim.NewPort(c, 1, 1, name)
+	incoming := f.incomingBufCap
+	if incoming <= 0 {
+		incoming = 1
+	}
+	outgoing := f.outgoingBufCap
+	if outgoing <= 0 {
+		outgoing = 1
+	}
+	return sim.NewPort(c, incoming, outgoing, name)
 }
 
 // DriverBuilder creates a new instance of Driver.
 type DriverBuilder struct {
-	engine sim.Engine
-	freq   sim.Freq
+	engine                sim.Engine
+	freq                  sim.Freq
+	portIncomingBufferCap int
+	portOutgoingBufferCap int
 }
 
 // WithEngine sets the engine.
@@ -27,10 +39,20 @@ func (b DriverBuilder) WithFreq(freq sim.Freq) DriverBuilder {
 	return b
 }
 
+// WithPortBufferDepth configures driver boundary-port incoming/outgoing capacity.
+func (b DriverBuilder) WithPortBufferDepth(incoming, outgoing int) DriverBuilder {
+	b.portIncomingBufferCap = incoming
+	b.portOutgoingBufferCap = outgoing
+	return b
+}
+
 // Build create a driver.
 func (b DriverBuilder) Build(name string) Driver {
 	d := &driverImpl{
-		portFactory: defaultPortFactory{},
+		portFactory: defaultPortFactory{
+			incomingBufCap: b.portIncomingBufferCap,
+			outgoingBufCap: b.portOutgoingBufferCap,
+		},
 	}
 
 	d.TickingComponent = sim.NewTickingComponent(name, b.engine, b.freq, d)

api/builder_microarch_test.go

@@ -0,0 +1,29 @@
+package api
+
+import (
+	"testing"
+
+	"github.com/sarchlab/akita/v4/sim"
+)
+
+func TestDriverBuilderWithPortBufferDepth(t *testing.T) {
+	engine := sim.NewSerialEngine()
+	driver := DriverBuilder{}.
+		WithEngine(engine).
+		WithFreq(1*sim.GHz).
+		WithPortBufferDepth(3, 5).
+		Build("Driver")
+
+	impl, ok := driver.(*driverImpl)
+	if !ok {
+		t.Fatalf("expected *driverImpl, got %T", driver)
+	}
+
+	factory, ok := impl.portFactory.(defaultPortFactory)
+	if !ok {
+		t.Fatalf("expected defaultPortFactory, got %T", impl.portFactory)
+	}
+	if factory.incomingBufCap != 3 || factory.outgoingBufCap != 5 {
+		t.Fatalf("unexpected driver port caps: in=%d out=%d", factory.incomingBufCap, factory.outgoingBufCap)
+	}
+}

api/driver.go

@@ -43,6 +43,7 @@ type Driver interface {
 
 	//
 	ReadMemory(x int, y int, addr uint32) uint32
+	ReadSharedMemory(x int, y int, addr uint32) uint32
 
 	// Run will run all the tasks that have been added to the driver.
 	Run()
@@ -80,6 +81,11 @@ func (d *driverImpl) ReadMemory(x int, y int, addr uint32) uint32 {
 	return tile.GetMemory(x, y, addr)
 }
 
+func (d *driverImpl) ReadSharedMemory(x int, y int, addr uint32) uint32 {
+	tile := d.device.GetTile(x, y)
+	return tile.ReadSharedMemory(x, y, addr)
+}
+
 // Tick runs the driver for one cycle.
 func (d *driverImpl) Tick() (madeProgress bool) {
 	madeProgress = d.doFeedIn() || madeProgress
@@ -142,7 +148,8 @@ func (d *driverImpl) doOneFeedInTask(task *feedInTask) bool {
 		err := port.Send(msg)
 		//fmt.Println(msg)
 		if err != nil {
-			panic("CGRA cannot handle the data rate")
+			// Keep task pending when downstream is temporarily back-pressured.
+			continue
 		}
 
 		timeValue := float64(d.Engine.CurrentTime() * 1e9)

api/feedin_backpressure_test.go

@@ -0,0 +1,48 @@
+package api
+
+import (
+	"testing"
+
+	gomock "github.com/golang/mock/gomock"
+	"github.com/sarchlab/akita/v4/sim"
+)
+
+func TestDoOneFeedInTaskBackpressureDoesNotPanic(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	engine := sim.NewSerialEngine()
+	d := &driverImpl{}
+	d.TickingComponent = sim.NewTickingComponent("Driver", engine, 1*sim.GHz, d)
+
+	port := NewMockPort(ctrl)
+	port.EXPECT().CanSend().Return(true).Times(2)
+	port.EXPECT().Name().Return("mock-port").AnyTimes()
+	port.EXPECT().AsRemote().Return(sim.RemotePort("driver-local")).AnyTimes()
+	port.EXPECT().Send(gomock.Any()).Return(sim.NewSendError()).Times(1)
+	port.EXPECT().Send(gomock.Any()).Return(nil).Times(1)
+
+	task := &feedInTask{
+		data:        []uint32{7},
+		localPorts:  []sim.Port{port},
+		remotePorts: []sim.RemotePort{sim.RemotePort("device-remote")},
+		stride:      1,
+		color:       0,
+		rounds:      1,
+		portRounds:  []int{0},
+	}
+
+	if progressed := d.doOneFeedInTask(task); progressed {
+		t.Fatal("expected no progress when Send returns backpressure error")
+	}
+	if task.portRounds[0] != 0 {
+		t.Fatalf("expected round to stay 0 after backpressure, got %d", task.portRounds[0])
+	}
+
+	if progressed := d.doOneFeedInTask(task); !progressed {
+		t.Fatal("expected progress once backpressure clears")
+	}
+	if task.portRounds[0] != 1 {
+		t.Fatalf("expected round to advance to 1, got %d", task.portRounds[0])
+	}
+}

api/mock_cgra_test.go

@@ -77,6 +77,7 @@ type Tile interface {
 	GetMemory(x int, y int, addr uint32) uint32
 	WriteMemory(x int, y int, data uint32, baseAddr uint32)
 	WriteSharedMemory(x int, y int, data []byte, baseAddr uint32)
+	ReadSharedMemory(x int, y int, addr uint32) uint32
 	GetTileX() int
 	GetTileY() int
 	GetRetVal() uint32

cgra/cgra.go

@@ -24,6 +24,26 @@ func (d Data) First() uint32 {
 	return d.Data[0]
 }
 
+// LaneCount returns the number of lanes carried by this value.
+func (d Data) LaneCount() int {
+	return len(d.Data)
+}
+
+// IsScalar reports whether the value is a single-lane scalar.
+func (d Data) IsScalar() bool {
+	return len(d.Data) <= 1
+}
+
+// Clone returns a deep copy of the value container.
+func (d Data) Clone() Data {
+	if len(d.Data) == 0 {
+		return Data{Pred: d.Pred}
+	}
+	cloned := make([]uint32, len(d.Data))
+	copy(cloned, d.Data)
+	return Data{Data: cloned, Pred: d.Pred}
+}
+
 // WithPred returns a copy with the given predicate flag.
 func (d Data) WithPred(pred bool) Data {
 	d.Pred = pred
@@ -32,5 +52,10 @@ func (d Data) WithPred(pred bool) Data {
 
 // FromSlice constructs a Data from a slice and optional predicate.
 func FromSlice(vals []uint32, pred bool) Data {
-	return Data{Data: vals, Pred: pred}
+	if len(vals) == 0 {
+		return Data{Pred: pred}
+	}
+	cloned := make([]uint32, len(vals))
+	copy(cloned, vals)
+	return Data{Data: cloned, Pred: pred}
 }