Minor code refactoring

- All derved backend class will have same name, #ifdefs will select
the correct backend.
- Add getTargetName method to backend class.
- Correct UART addresses in hello.s example.

sim/AtomSim.cpp

@@ -81,17 +81,17 @@ std::string signature_file 	= "";
 // Include Backend
 #include "Backend_AtomBones.hpp"
 
-// Backend name
-const std::string AtomSimBackend = "AtomBones";
-
-// Backend Object
-Backend_AtomBones *bkend;		
 
 // Default mem size for atomBones
-const unsigned long int default_mem_size = 134217728 + 3 + 1;	// 128MB (Code & Data) + 3 Bytes (Serial IO) + 1 (To make word access possible)
+// 128MB (Code & Data) + 3 Bytes (Serial IO) + 1 (To make word access possible on address 0x08000000)
+const unsigned long int default_mem_size = (128*1024*1024) + 3 + 1;	
 unsigned long int mem_size = default_mem_size;
 #endif
 
+
+// Backend Object
+Backend_AtomSim *bkend;
+
 /**
  * @brief Exit AtomSim
  * 
@@ -110,7 +110,7 @@ void ExitAtomSim(std::string message, bool exit_with_error)
 		std::cout << message << "\n";
 
 	// Destroy backend
-	bkend->~Backend_AtomBones();
+	bkend->~Backend_AtomSim();
 
 	// ===== Exit =====
 	if(exit_with_error)
@@ -238,7 +238,7 @@ void run(long unsigned int cycles)
 int main(int argc, char **argv)
 {
     if (verbose_flag)
-		std::cout << "AtomSim [" << AtomSimBackend << "]\n";
+		std::cout << "AtomSim [" << bkend->getTargetName() << "]\n";
 
 	// Initialize verilator
 	Verilated::commandArgs(argc, argv);
@@ -248,7 +248,7 @@ int main(int argc, char **argv)
 
 	// Create a new backend instance
 	#ifdef TARGET_ATOMBONES
-	bkend = new Backend_AtomBones(ifile, default_mem_size);
+	bkend = new Backend_AtomSim(ifile, default_mem_size);
 	#endif
 
 	if(trace_enabled == true)
@@ -342,8 +342,6 @@ int main(int argc, char **argv)
 				else
 					std::cout << "Trace was not enabled \n";
 			}
-			// ============== BACKEND SPECIFIC COMMANDS ==================
-			#ifdef TARGET_ATOMBONES
 			else if(token[0] == "mem")
 			{
 				if(token.size()<2)
@@ -358,25 +356,17 @@ int main(int argc, char **argv)
 					else										// Decimal Number
 						addr = std::stoi(token[1], nullptr, 10);
 
-					printf("%08x : %02x %02x %02x %02x\n", addr, bkend->mem->fetchByte(addr),
-						bkend->mem->fetchByte(addr+1),bkend->mem->fetchByte(addr+2), bkend->mem->fetchByte(addr+3));
+					uint32_t data = bkend->getMemContents(addr);
+					printf("%08x : %02x %02x %02x %02x\n", addr, (data & 0x000000ff), (data & 0x0000ff00)>>8, (data & 0x00ff0000)>>16, (data & 0xff000000)>>24);
 				}
 			}
 			else if(token[0] == "dumpmem")
 			{
 				if(token.size()<2)
 					throwError("CMD1", "\"dumpmem\" command expects filename as argument\n");
-
-				std::vector<std::string> fcontents;
-				for(unsigned int i=0; i<bkend->mem->size-4; i+=4)
-				{	
-					char hex [30];
-					sprintf(hex, "0x%08x\t:\t0x%08x", i, bkend->mem->fetchWord(i));
-					fcontents.push_back(hex);
-				}
-				fWrite(fcontents, token[1]);
+				else
+					bkend->dumpmem(token[1]);
 			}
-			#endif
 
 			else
 			{

sim/Backend.hpp

@@ -63,6 +63,13 @@ class Backend
     };
 
     public:
+
+    /**
+     * @brief Get the Target Name
+     * @return std::string 
+     */
+    virtual std::string getTargetName() = 0;
+
 	/**
 	 * @brief reset the backend
 	 */
@@ -138,6 +145,26 @@ class Backend
         }
     }
 
+    /**
+     * @brief Dump contents of memory into a file
+     * OVERRIDE THIS IN ANY DERIVED CLASSES
+     * @param file 
+     */
+    void dumpmem(std::string file)
+    {
+        throwError("", "Memory dumps not supported in current target");
+    }
+
+    /**
+     * @brief Get contents of a memory location
+     * OVERRIDE THIS IN ANY DERIVED CLASSES
+     */
+    uint32_t getMemContents(uint32_t addr)
+    {
+        throwError("", "Viewing memory content not suppoted in current target");
+        return 0;
+    }
+
 	/**
 	 * @brief Tick for one cycle
 	 * 

sim/Backend_AtomBones.hpp

@@ -255,7 +255,7 @@ class Memory
  * Backend class encapsulates the data 
  * probing and printing operations
  */
-class Backend_AtomBones: public Backend<VAtomBones>
+class Backend_AtomSim: public Backend<VAtomBones>
 {
 	public:
 	/**
@@ -267,7 +267,7 @@ class Backend_AtomBones: public Backend<VAtomBones>
 	/**
 	 * @brief Construct a new Backend object
 	 */
-	Backend_AtomBones(std::string ifile, unsigned long mem_size)
+	Backend_AtomSim(std::string ifile, unsigned long mem_size)
 	{
         // Construct Testbench object
         tb = new Testbench<VAtomBones>();
@@ -297,12 +297,17 @@ class Backend_AtomBones: public Backend<VAtomBones>
 	/**
 	 * @brief Destroy the Backend object
 	 */
-	~Backend_AtomBones()
+	~Backend_AtomSim()
 	{
 		delete tb;
 		delete mem;
 	}
 
+	std::string getTargetName()
+	{
+		return "AtomBones";
+	}
+
 	void serviceMemoryRequest()
 	{
 		// Clear all ack signals
@@ -497,4 +502,33 @@ class Backend_AtomBones: public Backend<VAtomBones>
 		}
 		prev_tx_we = cur_tx_we;
 	}
+
+	/**
+	 * @brief Dump contents of memoy into a file
+	 * @param file 
+	 */
+	void dumpmem(std::string file)
+	{
+		if(mem->size < 1*1024*1024)	// 1MB
+		{
+			std::vector<std::string> fcontents;
+			for(unsigned int i=0; i<mem->size-4; i+=4)
+			{	
+				char hex [30];
+				sprintf(hex, "0x%08x\t:\t0x%08x", i, mem->fetchWord(i));
+				fcontents.push_back(hex);
+			}
+			fWrite(fcontents, std::string(default_dump_dir)+"/"+file);
+		}
+		else
+			throwError("","Option not available due to excessive memory size (>1MB)\n", false);
+	}
+
+	 /**
+     * @brief Get contents of a memory location
+     */
+    uint32_t getMemContents(uint32_t addr)
+    {
+        return mem->fetchWord(addr);
+    }
 };

sw/examples/hello/hello.s

@@ -1,8 +1,8 @@
 .global main
 .text
 
-.equ TX_ADDRESS, 0x00014001               
-.equ TX_ACK_ADDRESS, 0x00014002         
+.equ TX_ADDRESS, 0x08000001
+.equ TX_ACK_ADDRESS, 0x08000002
 
 main:
     la a0, msg

sw/lib/link.ld

@@ -11,8 +11,8 @@ ENTRY(_start)
 /* MEMORY LAYOUT */
 MEMORY
 {
-    ROM (rx) : ORIGIN = 0x00000000, LENGTH = 64M    /* 64 kb @ 0x0*/
-    RAM (rwx): ORIGIN = 0x04000000, LENGTH = 64M    /* 16 kb @ 0x10000 (65536)*/
+    ROM (rx) : ORIGIN = 0x00000000, LENGTH = 64M    /* 64 MB @ 0x0*/
+    RAM (rwx): ORIGIN = 0x04000000, LENGTH = 64M    /* 64 MB @ 0x10000 (0x04000000)*/
 }
 
 SECTIONS