Fix DataCache bug (interaction between the victim buffer and the memory read request in execute/memory stages)

freeRTOS pass

src/main/scala/vexriscv/TestsWorkspace.scala

@@ -277,7 +277,7 @@ object TestsWorkspace {
       }*/
 //      toplevel.writeBack.input(config.PC).addAttribute(Verilator.public)
 //      toplevel.service(classOf[DecoderSimplePlugin]).bench(toplevel)
-
+     // toplevel.children.find(_.isInstanceOf[DataCache]).get.asInstanceOf[DataCache].io.cpu.execute.addAttribute(Verilator.public)
       toplevel
     }
   }

src/main/scala/vexriscv/ip/DataCache.scala

@@ -59,7 +59,7 @@ object Bypasser{
   }
 
 
-  //shot readValid path
+  //short readValid path
   def writeFirstMemWrap(readValid : Bool, readLastAddress : UInt, readLastData : Bits,writeValid : Bool, writeAddress : UInt, writeData : Bits,writeMask : Bits) : Bits = {
     val writeHit    = writeValid && writeAddress === readLastAddress
     val writeSample = readValid || writeHit
@@ -412,6 +412,8 @@ class DataCache(p : DataCacheConfig) extends Component{
   }
 
 
+  val cpuMemoryStageNeedReadData = Bool()
+
   val victim = new Area{
     val requestIn = Stream(cloneable(new Bundle{
       //      val way = UInt(log2Up(wayCount) bits)
@@ -438,7 +440,7 @@ class DataCache(p : DataCacheConfig) extends Component{
         dataReadCmd.payload := request.address(lineRange) @@ readLineCmdCounter(readLineCmdCounter.high - 1 downto 0)
         way.dataReadRspOneKeepAddress := True
       } otherwise {
-        when(!dataReadRestored) {
+        when(!dataReadRestored && cpuMemoryStageNeedReadData) {
           dataReadCmd.valid := True
           dataReadCmd.payload := way.dataReadRspOneAddress //Restore stage one readed value
         }
@@ -447,6 +449,7 @@ class DataCache(p : DataCacheConfig) extends Component{
     }
 
     dataReadRestored clearWhen(request.ready)
+    io.cpu.memory.haltIt :=  cpuMemoryStageNeedReadData && request.valid && !dataReadRestored
 
     //Fill the buffer with line read responses
     val readLineRspCounter = Reg(UInt(log2Up(memTransactionPerLine + 1) bits)) init(0)
@@ -503,8 +506,7 @@ class DataCache(p : DataCacheConfig) extends Component{
     io.cpu.memory.mmuBus.cmd.isValid := io.cpu.memory.isValid  && request.kind === MEMORY //TODO filter request kind
     io.cpu.memory.mmuBus.cmd.virtualAddress := request.address
     io.cpu.memory.mmuBus.cmd.bypassTranslation := request.way
-
+    cpuMemoryStageNeedReadData := io.cpu.memory.isValid && request.kind === MEMORY && !request.wr
-    io.cpu.memory.haltIt := io.cpu.memory.isValid && request.kind === MEMORY && !request.wr && victim.request.valid && !victim.dataReadRestored
   }
 
   val stageB = new Area {

src/test/cpp/regression/main.cpp

@@ -746,6 +746,9 @@ public:
 
 
 #ifdef DBUS_CACHED
+
+//#include "VVexRiscv_DataCache.h"
+
 class DBusCached : public SimElement{
 public:
 	uint32_t address;
@@ -766,6 +769,23 @@ public:
 	}
 
 	virtual void preCycle(){
+	    VL_IN8(io_cpu_execute_isValid,0,0);
+	    VL_IN8(io_cpu_execute_isStuck,0,0);
+	    VL_IN8(io_cpu_execute_args_kind,0,0);
+	    VL_IN8(io_cpu_execute_args_wr,0,0);
+	    VL_IN8(io_cpu_execute_args_size,1,0);
+	    VL_IN8(io_cpu_execute_args_forceUncachedAccess,0,0);
+	    VL_IN8(io_cpu_execute_args_clean,0,0);
+	    VL_IN8(io_cpu_execute_args_invalidate,0,0);
+	    VL_IN8(io_cpu_execute_args_way,0,0);
+
+//		if(top->VexRiscv->dataCache_1->io_cpu_execute_isValid && !top->VexRiscv->dataCache_1->io_cpu_execute_isStuck
+//				&& top->VexRiscv->dataCache_1->io_cpu_execute_args_wr){
+//			if(top->VexRiscv->dataCache_1->io_cpu_execute_args_address == 0x80025978)
+//				cout << "WR 0x80025978 = " << hex << setw(8) << top->VexRiscv->dataCache_1->io_cpu_execute_args_data << endl;
+//			if(top->VexRiscv->dataCache_1->io_cpu_execute_args_address == 0x8002596c)
+//				cout << "WR 0x8002596c = " << hex << setw(8) << top->VexRiscv->dataCache_1->io_cpu_execute_args_data << endl;
+//		}
 		if (top->dBus_cmd_valid && top->dBus_cmd_ready) {
 			if(pendingCount == 0){
 				pendingCount = top->dBus_cmd_payload_length+1;
@@ -1583,6 +1603,9 @@ int main(int argc, char **argv, char **env) {
 				Workspace w("debugPluginExternal");
 				w.loadHex("../../resources/hex/debugPluginExternal.hex");
 				w.noInstructionReadCheck();
+				//w.setIStall(false);
+				//w.setDStall(false);
+
 				#if defined(TRACE) || defined(TRACE_ACCESS)
 					//w.setCyclesPerSecond(5e3);
 					//printf("Speed reduced 5Khz\n");
@@ -1593,7 +1616,7 @@ int main(int argc, char **argv, char **env) {
 
 
 
-			TestA().run();
+			redo(REDO,TestA().run();)