From a366ed8f91bbd7f7f7a77b95b1550bd74c43fe3e Mon Sep 17 00:00:00 2001
From: Peter Ehses <ehses@rhrk.uni-kl.de>
Date: Tue, 16 Sep 2014 10:27:14 +0200
Subject: [PATCH] easy error model from patrick implemented

---
 dram/src/error/flip_memory.cpp | 208 +++++++++++++++++++++++++++++++++
 dram/src/error/flip_memory.h   |  53 +++++++++
 dram/src/error/nest_map.cpp    | 117 +++++++++++++++++++
 dram/src/error/nest_map.h      |  46 ++++++++
 4 files changed, 424 insertions(+)
 create mode 100644 dram/src/error/flip_memory.cpp
 create mode 100644 dram/src/error/flip_memory.h
 create mode 100644 dram/src/error/nest_map.cpp
 create mode 100644 dram/src/error/nest_map.h

diff --git a/dram/src/error/flip_memory.cpp b/dram/src/error/flip_memory.cpp
new file mode 100644
index 00000000..9b2b5071
--- /dev/null
+++ b/dram/src/error/flip_memory.cpp
@@ -0,0 +1,208 @@
+#include "flip_memory.h"
+#include <time.h>
+// Console out
+#include <iostream>
+
+// String conversion (debugging)
+#include <stdio.h>
+#include <stdlib.h>
+
+using namespace std;
+
+flip_memory::flip_memory() {
+	// Initialize Random generator with current system time
+	// Only do this once in a simulation
+	srand(time(NULL));
+    
+    // Fixed values for development process
+	TEMPERATURE = 90;
+	
+	// Initialize number of bit errors
+	BIT_ERR = 0;
+	
+	errormap = new nest_map("errors.csv");
+	xade = new xmlAddressDecoder("config.xml");
+    
+	// Constants for address calculations
+    ROWS_PER_BANK = xade->getRowSize();
+	COLS_PER_ROW = xade->getColumSize();
+    BYTES_PER_COL = xade->getBytesSize();
+	BITS_PER_ROW = COLS_PER_ROW * BYTES_PER_COL * 8;
+    
+    // Fill array with random addresses
+	initWeakCells();
+}
+
+flip_memory::~flip_memory() {   
+	cout << endl << endl << endl << "Bit-Fehler: " << BIT_ERR << endl << endl << endl;
+}
+
+void flip_memory::getUnifiedNode(unsigned int addr, node *n) {
+	xade->getNode(addr, n);
+	n->channel = 0;
+	n->bank = 0;
+}
+
+// Decide which Cells will be weak cells
+void flip_memory::initWeakCells() {
+    unsigned int maxWeakCells = errormap->getMaxWeakCells();
+    weakCells = new unsigned int*[maxWeakCells];
+    
+    for (unsigned int i=0; i<maxWeakCells; i++) {
+        unsigned int row, col, bit;
+        weakCells[i] = new unsigned int[4];
+            
+            row = (unsigned int) (rand() % ROWS_PER_BANK);
+            col = (unsigned int) (rand() % COLS_PER_ROW);
+            bit = (unsigned int) (rand() % (BYTES_PER_COL*8));
+
+        // Avoid duplicates in weakCells[]
+        bool found = false;
+        
+        for (unsigned int k=0; k<i; k++) {
+            if ((weakCells[k][0]==row) && (weakCells[k][1]==col) && (weakCells[k][2]==bit)) {
+                found = true;
+                break;
+            }
+        }
+        if(found == true) {
+            i--;
+        }
+        else
+        {
+            weakCells[i][0] = row;
+            weakCells[i][1] = col;
+            weakCells[i][2] = bit;     // Bit position in column
+            weakCells[i][3] = 0;       // Flag whether this position has already flipped
+        } 
+    }
+}
+
+
+// Reset "HasFlipped"-Flag, set Refresh-Timestamp
+void flip_memory::resetCell(node n) {
+    unsigned int arraySize = errormap->getMaxWeakCells();
+    
+    for (unsigned int i=0; i<arraySize; i++) {
+        if ((weakCells[i][0] == n.row) && (weakCells[i][1] == n.colum)) weakCells[i][3] = 0;
+    }
+
+    refr[n.row] = sc_time_stamp();
+}
+
+
+// Store data in memory
+void flip_memory::store(tlm_generic_payload &trans) {
+	unsigned int t_addr, t_len;
+	unsigned char* t_ptr;
+
+	t_addr = trans.get_address();
+	t_len = trans.get_data_length();
+	t_ptr = trans.get_data_ptr();
+	
+	// Generate XML Node
+	node no;
+	getUnifiedNode(t_addr, &no);
+		
+	for (unsigned int i = 0; i < t_len; i+=BYTES_PER_COL) {
+		// Store data in vector of size BYTES_PER_COL temporarily, later write to mem
+		vector<unsigned char> v;
+		for (unsigned int n = 0; n < BYTES_PER_COL; n++) v.push_back(*(t_ptr + i + n));
+		
+		// Switch to next column if necessary
+		if (i > 0) no.colum++;
+
+		// Swap around if more columns addressed than exist
+		if (no.colum>(COLS_PER_ROW - 1)) no.colum -= BURSTLENGTH*BYTES_PER_COL;
+
+		unsigned int addr = xade->getAddress(&no);
+
+		mem.insert(pair<unsigned int, vector<unsigned char> >(addr, v));
+        
+		// Reset weak cells; they have reliable data now till next check
+		resetCell(no);
+	}
+	
+	trans.set_response_status(TLM_OK_RESPONSE);
+}
+
+
+void flip_memory::load(tlm_generic_payload &trans) {
+	unsigned int t_addr, t_len;
+	unsigned char* t_ptr;
+
+	t_addr = trans.get_address();
+	t_len = trans.get_data_length();
+	t_ptr = trans.get_data_ptr();
+
+	// Generate XML Node
+	node no;
+	getUnifiedNode(t_addr, &no);
+	
+	
+	if (mem.count(t_addr) > 0)
+	{
+		for (unsigned int i = 0; i < t_len; i += BYTES_PER_COL) {
+			// Switch to next column if necessary
+			if (i > 0) no.colum++;
+
+			// Swap around if more columns addressed than exist
+			if (no.colum>(COLS_PER_ROW - 1)) no.colum -= BURSTLENGTH*BYTES_PER_COL;
+
+			unsigned int addr = xade->getAddress(&no);
+
+			// Write out data
+			for (unsigned int n = 0; n < BYTES_PER_COL; n++)
+			{
+				*(t_ptr + i + n) = mem[addr][n];	
+			}
+		}
+	
+	}
+
+	trans.set_response_status(TLM_OK_RESPONSE);
+}
+
+
+// Function to trigger row refresh externally; errors are manifested
+void flip_memory::refresh(unsigned int row) {
+	// How many Bits have flipped?
+    sc_time deltaT = sc_time_stamp() - refr[row];
+	unsigned int n = errormap->getFlipRate(TEMPERATURE, deltaT);
+    	
+    // Flip the first n Bits in array
+    for (unsigned int i=0; i<n; i++) {
+        // Check if Bit has not flipped yet
+        if (weakCells[i][3] == 0 && weakCells[i][0] == row) {
+            node no;
+            getUnifiedNode(0, &no);
+            no.row = weakCells[i][0];
+            no.colum = weakCells[i][1];
+            
+            unsigned int addr = xade->getAddress(&no);
+            unsigned int byte = weakCells[i][2] / 8;   // Byte position in column
+            unsigned int bit = weakCells[i][2] % 8;    // Bit position in byte
+            
+            unsigned char mask = pow(2, bit);           // 1 Byte long character
+            mask = ~mask;				                // invert mask (only one 0) and AND it later
+
+            // Address has already been allocated?
+            if (mem.count(addr) > 0) {
+                char memBefore = mem[addr][byte];
+                
+                mem[addr][byte] &= mask;
+                weakCells[i][3] = 1;
+                
+                char memAfter = mem[addr][byte];
+                
+                // Data has changed?
+                if (memBefore!=memAfter) {
+                    BIT_ERR++;
+                }
+            }  
+        }
+    }
+    
+	refr[row] = sc_time_stamp();
+}
+
diff --git a/dram/src/error/flip_memory.h b/dram/src/error/flip_memory.h
new file mode 100644
index 00000000..cc4abb75
--- /dev/null
+++ b/dram/src/error/flip_memory.h
@@ -0,0 +1,53 @@
+#ifndef _FLIP_MEMORY_H
+#define _FLIP_MEMORY_H
+#include "nest_map.h"
+#include <tlm.h>
+#include <map>
+#include "common/xmlAddressdecoder.h"
+
+
+using namespace tlm;
+using namespace std;
+
+class flip_memory {
+private:
+	xmlAddressDecoder *xade;
+
+	// Remember to adjust this value by hand when editing in simulation
+	static const unsigned int BUSWIDTH = 128;
+	static const unsigned int BURSTLENGTH = 1;
+	
+	// Compute number of generated bit errors
+	unsigned int BIT_ERR;
+
+	nest_map *errormap;
+	map <unsigned int, vector<unsigned char> > mem;
+	map <unsigned int, sc_time> refr;
+    unsigned int **weakCells;
+	
+    // This will be an input from ICE 3D
+	unsigned int TEMPERATURE;
+	
+	unsigned int ROWS_PER_BANK;
+	unsigned int COLS_PER_ROW;
+	unsigned int BYTES_PER_COL;
+	unsigned int BITS_PER_ROW;
+
+    // Generates an XML node which is tied to one memory class instance
+	void getUnifiedNode(unsigned int addr, node *n);
+    
+    // Decide randomly which cells are weak
+    void initWeakCells();
+    
+    // Reset "HasFlipped"-Flag, set Refresh-Timestamp
+    void resetCell(node n);
+
+public:
+	flip_memory();
+	~flip_memory();
+	void store(tlm_generic_payload &trans);
+	void load(tlm_generic_payload &trans);
+    // Trigger row refresh externally; errors are manifested
+	void refresh(unsigned int row);
+};
+#endif
diff --git a/dram/src/error/nest_map.cpp b/dram/src/error/nest_map.cpp
new file mode 100644
index 00000000..25aaa009
--- /dev/null
+++ b/dram/src/error/nest_map.cpp
@@ -0,0 +1,117 @@
+#include "nest_map.h"
+#include <limits>
+
+nest_map::nest_map(string fn) {
+	initMap(fn);
+}
+
+nest_map::~nest_map(void) {
+	delete tr;
+}
+
+// Read data from CSV file with filename "fn" and store it inside the errormap instance
+void nest_map::initMap(string fn) {
+	unsigned int noOfLines = 0;
+    maxWeakCells = 0;
+	string line;
+
+	ifstream input;
+	input.open(fn.c_str(), ios::in);
+
+	if (input.is_open()) {
+        // Count number of entries in CSV file
+		while (getline(input, line)) {
+			++noOfLines;
+		}
+		input.clear();
+		input.seekg(0, ios::beg);
+
+		// Knowing the size, allocate the errormap
+		size = noOfLines;
+		tr = new triple[noOfLines];
+		
+        // Copy entries from CSV to errormap
+		for (unsigned int i = 0; i < noOfLines; i++) {
+			getline(input, line);
+
+			// "split" returns a 3d vector with temperature, time, number of errors (this order)
+			vector<string> tmp = split(line, *",");
+
+			tr[i].T = atoi(tmp[0].c_str());
+            // Don't forget to set right unit for times from CSV here
+			tr[i].t = sc_time(atoi(tmp[1].c_str()), SC_MS);
+			tr[i].n = atoi(tmp[2].c_str());
+			
+            // Search the largest entry of n in list
+            if (tr[i].n > maxWeakCells) {
+                maxWeakCells = tr[i].n;
+            }
+		}		
+        
+		input.close();
+	}
+	else cout << "Fehler beim Oeffnen der Daten" << endl;
+}
+
+
+// Retrieve number of flipping bits which fits best to temperature input and time since last refresh
+unsigned int nest_map::getFlipRate(unsigned int T_in, sc_time t_in) {
+	unsigned int temperatureClosest = 0;
+    unsigned int noOfWeakCells = 0;
+    sc_time timeLowerBound = sc_time(0,SC_SEC);
+    
+	// Search all entries in LUT for temperature closest to T_in
+    for (unsigned int i = 0; i < size; i++) {
+        if (abs((double)tr[i].T-(double)T_in)<abs((double)temperatureClosest-(double)T_in)) {
+            temperatureClosest = tr[i].T;
+        }
+    }
+    
+    // Which time mark has already been passed?
+    for (unsigned int i = 0; i < size; i++) {
+        // Only check entries with temperature temperatureClosest
+        if (tr[i].T == temperatureClosest) {
+            if ((tr[i].t.value() > timeLowerBound.value()) && (t_in.value() >= tr[i].t.value())) { 
+                timeLowerBound = tr[i].t;
+                noOfWeakCells = tr[i].n;
+            }
+        }
+    }
+	return noOfWeakCells;
+}
+
+
+unsigned int nest_map::getMaxWeakCells() {
+    return maxWeakCells;
+}
+
+
+// Remove all spaces out of a string and split it at every occurance of char c
+vector<string> nest_map::split(string str, char c) {
+	vector<string> tmp_v;
+	string tmp_str = str;
+
+	// Remove spaces
+	while (true){
+		size_t posSpace = tmp_str.find_first_of(" ");
+		if (posSpace == string::npos) {
+            break;
+        }
+		tmp_str.erase(posSpace, 1);
+	}
+
+	// Split string at every occurance of char c
+	while (true)
+	{
+		size_t pos_del = tmp_str.find_first_of(c);
+		if (pos_del == string::npos) {
+			tmp_v.push_back(tmp_str);
+			break;
+		}
+
+		tmp_v.push_back(tmp_str.substr(0, pos_del));
+		tmp_str.erase(0, pos_del + 1);
+	}
+
+	return tmp_v;
+}
\ No newline at end of file
diff --git a/dram/src/error/nest_map.h b/dram/src/error/nest_map.h
new file mode 100644
index 00000000..58ce02b7
--- /dev/null
+++ b/dram/src/error/nest_map.h
@@ -0,0 +1,46 @@
+#ifndef _NEST_MAP_H
+#define _NEST_MAP_H
+
+#include <systemc.h>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <fstream>
+#include <stdlib.h>
+
+using namespace std;
+
+class nest_map {
+	private:
+		// Helper class to store triples of temperature, (retention) time and number of errors
+		struct triple {
+			unsigned int T;
+			sc_time t;
+			unsigned int n;
+		};
+
+		// Array of "triple" with dynamic size
+		triple *tr;
+
+        // Number of entrys in tr[]
+		unsigned int size;
+        
+        // Largest value of n in tr[]
+        unsigned int maxWeakCells;
+        
+        // Default CSV filename
+		const string def_fn;
+
+		void initMap(string fn);
+		vector<string> split(string str, char c);
+
+	public:
+		nest_map(string fn);
+		~nest_map();
+        
+        // Retrieve number of flipping bits which fits best to temperature input and time since last refresh
+		unsigned int getFlipRate(unsigned int T, sc_time t);
+        
+        unsigned int getMaxWeakCells();
+};
+#endif