您的位置：技术中心首页 > 逻辑验证 >> Verilog PLI教程 --- 第五部分 PLI例子

Verilog PLI教程 --- 第五部分 PLI例子

作者：5life 时间：2006-02-19 05:58:23 来自：本站原创浏览次数：980 文字大小：【大】【中】【小】

简介：本Verilog PLI教程翻译自asic-world网站的Verilog PLI教程，由于译者水平有限，难免会有一些错误，请与译者5life站内联系。原文地址为：http://www.asic-world.com/verilog/pli5.html#PLI_Example

在剩下的教程中，让我们用测试向量发生器，监测器，检验器以及任何用C代码编写的来验证计数器例子。

Testbench将有下列：

C编写的时钟发生器
时钟发生器的HDL wrapper
C编写的测试产生器
测试产生器的HDL wrapper
C编写的监测器和检验器
Mointor Checker HDL wrapper
在verilog中的DUT/Monitor/clock/test 产生器的例化

时钟发生器
一般我们不希望在PLI中产生时钟发生器，最好是在verilog中实现。

1	#include "acc_user.h"
2	#include "veriuser.h"
3
4	// Define the ON and OFF time of clock
5	#define PERIOD 5
6
7	// Data structure
8	struct clkData {
9		int clk;
10		int clkCnt;
11	};
12
13	// Main routine which toggles the clock
14	void clkGen () {
15		// Get the stored workarea
16		struct clkData data = ( struct clkData )tf_igetworkarea(tf_getinstance());
17		if (data->clkCnt == PERIOD) {
18			data->clk = (data->clk == 0) ? 1 : 0;
19			data->clkCnt = 0;
20			//io_printf("%d Current clk = %dn",tf_gettime(), data->clk);
21		} else {
22			data->clkCnt ++;
23		}
24		// Drive the clock signal in HDL
25		tf_putp (1, data->clk);
26	}
27
28	// checktf() routine
29	// This function inits the objects and also stores the object in workarea
30	void clkInit() {
31		struct clkData data = ( struct clkData )malloc( sizeof( struct clkData ) );
32		data->clkCnt = 0;
33		data->clk = 0;
34		tf_setworkarea(data);
35	}
36
37	// misctf() routine
38	// This routine is called after 1 tick
39	void clkReactive (int data, int reason, int paramvc) {
40		// if callback reason is reactive, then call clkGen function
41		if (reason == reason_reactivate) {
42			clkGen();
43		}
44		// Set the callback delay to 1 tick
45		tf_setdelay(1);
46	}

Clock Generator HDL Wrapper

1	module clkGen(clk);
2	output clk;
3	reg clk;
4
5	initial $clkGen(clk);
6
7	endmodule

Counter Monitor

1	#include "acc_user.h"
2	#include "veriuser.h"
3	#include <malloc.h>
4	#include <string.h>
5
6	struct myCounter {
7		handle count;
8		handle enable;
9		handle reset;
10		handle clk;
11		char *count_value;
12		char *enable_value;
13		char *reset_value;
14		char *clk_value;
15		char *clk_last_value;
16		int checker_count;
17		int count_width;
18		int error;
19		int error_time;
20	};
21
22	// Multi-bit vector to integer conversion.
23	int pliConv (char *in_string, int no_bits, int sim_time) {
24		int conv = 0;
25		int i = 0;
26		int j = 0;
27		int bin = 0;
28		for ( i = no_bits-1; i >= 0; i = i - 1) {
29			if (*(in_string + i) == 49) {
30				bin = 1;
31			} else if (*(in_string + i) == 120) {
32				io_printf ( "%d counterMonitor : WARNING : X detectedn" , sim_time);
33				bin = 0;
34			} else if (*(in_string + i) == 122) {
35				io_printf ( "%d counterMonitor : WARNING : Z detectedn" , sim_time);
36				bin = 0;
37			} else {
38				bin = 0;
39			}
40			conv = conv + (1 << j)*bin;
41			j ++;
42		}
43		return conv;
44	}
45
46	void counterModel (struct myCounter *counter) {
47		int current_value ;
48		int time = tf_gettime();
49		// Our model checks only at posedge
50		if ((strcmp(counter->clk_value, "1" ) == 0) && (strcmp(counter->clk_last_value, "0" ) == 0)) {
51		// Conver the current count value
52		current_value = pliConv(counter->count_value,counter->count_width,time);
53		// Check input control signal to floating or UnKnown
54		if (strcmp(counter->reset_value, "x" ) == 0) {
55		io_printf( "%d counterMonitor : WARNING : reset is xn" , time);
56	}
57	if (strcmp(counter->reset_value, "z" ) == 0) {
58	io_printf( "%d counterMonitor : WARNING : reset is zn" , time);
59	}
60	if (strcmp(counter->enable_value, "x" ) == 0) {
61	io_printf( "%d counterMonitor : WARNING : enable is xn" , time);
62	}
63	if (strcmp(counter->enable_value, "z" ) == 0) {
64	io_printf( "%d counterMonitor : WARNING : enable is zn" , time);
65	}
66	// Increment monitor counter and compare only if enable is 1 and reset is not active
67	if (strcmp(counter->enable_value, "1" ) == 0 && strcmp(counter->reset_value, "0" ) == 0) {
68	if (counter->checker_count != current_value) {
69		io_printf( "%d counterMonitor : ERROR : Current value of monitor is %d dut is %dn" ,
70		time, counter->checker_count, current_value);
71		counter->error ++;
72		if (counter->error == 1) counter->error_time = time;
73	} else {
74		io_printf( "%d counterMonitor : INFO : Current value of monitor is %d dut is %dn" ,
75		time, counter->checker_count, current_value);
76	}
77	counter->checker_count = (counter->checker_count == 15) ? 0 : counter->checker_count + 1;
78	// Reset monitor counter if reset is active
79	} else if (strcmp(counter->reset_value, "1" ) == 0) {
80	io_printf( "%d counterMonitor : INFO : Reset is assertedn" , time);
81	counter->checker_count = 0;
82	}
83	}
84	// Update the clock state
85	strcpy(counter->clk_last_value,counter->clk_value);
86	}
87
88	// misctf
89	void counterMonitor(int data, int reason, int paramvc) {
90		struct myCounter counter = (struct myCounter ) tf_igetworkarea(tf_getinstance());
91		if ((reason == reason_paramvc) \|\| (reason == reason_paramdrc)) {
92			tf_synchronize( );
93		} else if (reason == reason_synch) {
94			counter->clk = acc_handle_tfarg(1);
95			counter->reset = acc_handle_tfarg(2);
96			counter->enable = acc_handle_tfarg(3);
97			counter->count = acc_handle_tfarg(4);
98			// Get the values
99			counter->clk_value = acc_fetch_value(counter->clk, "%b" , 0);
100			counter->reset_value = acc_fetch_value(counter->reset, "%b" , 0);
101			counter->enable_value = acc_fetch_value(counter->enable, "%b" , 0);
102			counter->count_value = acc_fetch_value(counter->count, "%b" , 0);
103			counter->count_width = acc_fetch_size (counter->count);
104			// Call the counter model
105			counterModel (counter);
106		}
107		// Print simulation stats when $finish is called
108		if (reason == reason_finish) {
109			io_printf( "=========================================n" );
110			if (counter->error != 0) {
111				io_printf ( " Simulation : FAILEDn" );
112				io_printf ( " Mismatched %dn" ,counter->error);
113				io_printf ( " First Mismatch at time %dn" , counter->error_time);
114			} else {
115				io_printf ( " Simulation : PASSEDn" );
116			}
117			io_printf( "=========================================n" );
118		}
119	}
120
121	// calltf()
122	void initCounter(int data, int reason) {
123		struct myCounter *counter;
124		// Allocate memory for all variables necessary to manage a
125		// single instance of the model.
126		counter = (struct myCounter *) malloc (sizeof(struct myCounter));
127		// Initialize this instance of the model.
128		counter->clk = acc_handle_tfarg(1);
129		counter->reset = acc_handle_tfarg(2);
130		counter->enable = acc_handle_tfarg(3);
131		counter->count = acc_handle_tfarg(4);
132		// Save a copy of the present clk value.
133		counter->clk_last_value = acc_fetch_value(counter->clk, "%b" , 0);
134		// Enable callback of `counter_monitor` whenever
135		// any argument to `$counter_monitor` changes.
136		tf_asynchon();
137		// Set initial counter value to 0.
138		counter->checker_count = 0;
139		counter->error = 0;
140		counter-> error_time = 0;
141		// Save the model data with this instance of `$counterMonitor`.
142		tf_setworkarea((char *)counter);
143	}

Counter Monitor HDL Wrapper

1	module counterMonitor (clk, reset, enable, count);
2	input clk, reset, enable;
3	input [3:0] count;
4
5	wire clk, reset, enable;
6	wire [3:0] count;
7
8	initial $counterMonitor(clk,reset,enable,count);
9
10	endmodule

Counter TestGen

1	#include "acc_user.h"
2	#include "veriuser.h"
3	#include "string.h"
4	#include "stdio.h"
5
6	#define IDLE 0
7	#define INCR 1
8	#define WAIT 2
9	#define DRIVE 3
10	#define DONE 4
11
12	struct testGenObject {
13		char* testFile;
14		int debug;
15		char cmdArray[100] [100];
16		int cmdSize;
17		int CmdPointer;
18		char* command;
19		int wait;
20		int value;
21		int clkCnt;
22		int state;
23		handle count;
24		handle enable;
25		handle reset;
26		handle clk;
27		char* clk_value;
28		char *clk_last_value;
29	};
30
31	static struct testGenObject *object;
32
33	// Increment counter
34	void waitTicks () {
35		object->clkCnt = object->clkCnt + 1;
36	}
37
38	// This function loads the content of test file into
39	// object command array
40	void loadTest() {
41		FILE *testFile;
42		char currentLine [100];
43		object->cmdSize = 0;
44		if((testFile = fopen(object->testFile, "r" )) == NULL) {
45		printf( "Error Opening File.n" );
46	}
47	while (fgets(currentLine, sizeof(currentLine), testFile) != NULL ) {
48		// Store the line cmdArray
49		strcpy(object->cmdArray[object->cmdSize], currentLine);
50		// print the line number and data
51		if (object->debug) printf( "Line %d: %sn" , object->cmdSize, object->cmdArray[object->cmdSize]);
52		// Get each line from the test file
53		object->cmdSize ++;
54	}
55	// Close the test file
56	fclose(testFile);
57	}
58
59	// This function process command line options
60	void processCmdOptions () {
61		// Get debug option
62		if (mc_scan_plusargs( "plidebug" ) != NULL) {
63		object->debug = 1;
64	} else {
65		object->debug = 0;
66	}
67	// Get test file name
68	if (mc_scan_plusargs( "test=" ) == NULL) {
69	printf( "ERROR : No test file option passed, use +test=testfilen" );
70	} else {
71	object->testFile = mc_scan_plusargs( "test=" );
72	if (object->debug) printf( "Test file name %sn" ,object->testFile);
73	}
74	}
75
76	void doTest() {
77		char* ptoks;
78		char* tcmd;
79		s_setval_delay delay_s;
80		s_setval_value value_s;
81		// Get current clock value
82		object->clk_value = acc_fetch_value(object->clk, "%b" , 0);
83		// BFM drives only at rising edge of clock
84		if (!strcmp(object->clk_last_value, "1" ) && !strcmp(object->clk_value, "0" )) {
85		switch (object->state) {
86			case IDLE : if (object->debug) printf( "%d Current state is IDLEn" , tf_gettime());
87			if (object->CmdPointer < object->cmdSize) {
88				tcmd = object->cmdArray[object->CmdPointer];
89				if (object->debug) printf ( "Test line %d current command-%s" ,object->CmdPointer, tcmd);
90				ptoks = strtok(tcmd, ":" );
91				int lcnt = 0;
92				while(ptoks != NULL) {
93					if (*ptoks != '=') {
94						if (lcnt == 0) {
95							object->wait = atoi(ptoks);
96							if (object->debug) printf( "Wait : %dn" , object->wait);
97						} else if (lcnt == 1) {
98							object->command = ptoks;
99							if (object->debug) printf( "Command : %sn" , ptoks);
100						} else {
101							object->value = atoi(ptoks);
102							if (object->debug) printf( "Value : %dn" , object->value);
103						}
104						lcnt ++;
105					}
106					ptoks = strtok(NULL, " " );
107				}
108				object->CmdPointer ++ ;
109				if (object->wait == 0) {
110					if (object->debug) printf( "%d Next State DRIVEn" , tf_gettime());
111					object->state = DRIVE;
112					doTest();
113				} else {
114					if (object->debug) printf( "%d Next State WAITn" , tf_gettime());
115					object->state = WAIT;
116				}
117			} else {
118				if (object->debug) printf( "%d Next State DONEn" , tf_gettime());
119				object->state = DONE;
120			}
121			break;
122			case WAIT : if (object->debug) printf( "%d Current state is WAIT : %dn" , tf_gettime(), object->clkCnt);
123			if ((object->clkCnt + 1) >= object->wait) {
124				object->wait = 0;
125				object->clkCnt = 0;
126				if (object->debug) printf( "%d Next State DRIVEn" , tf_gettime());
127				object->state = DRIVE;
128				doTest();
129			} else {
130				waitTicks();
131			}
132			break;
133			case DRIVE : if (object->debug) printf( "%d Current state is DRIVEn" , tf_gettime());
134			value_s.format = accIntVal;
135			delay_s.model = accNoDelay;
136			delay_s.time.type = accTime;
137			delay_s.time.low = 0;
138			delay_s.time.high = 0;
139			if (!strcmp(object->command, "reset" )) {
140			value_s.value.integer = object->value;
141			acc_set_value(object->reset,&value_s,&delay_s);
142		} else if (!strcmp(object->command, "enable" )) {
143		value_s.value.integer = object->value;
144		acc_set_value(object->enable,&value_s,&delay_s);
145	} else {
146		if (object->debug) printf( "ERROR : What command do you wantn" );
147	}
148	if (object->debug) printf( "%d Next State IDLEn" , tf_gettime());
149	object->state = IDLE;
150	break;
151	case DONE : if (object->debug) printf( "%d Current state is DONEn" , tf_gettime());
152	tf_dofinish();
153	break;
154	default : object->state = IDLE;
155	break;
156	}
157	}
158	object->clk_last_value = acc_fetch_value(object->clk, "%b" , 0);
159	}
160
161	void initCounterTestGen () {
162		//acc_initialize( );
163		//acc_configure( accDisplayErrors, "false" );
164		object = (struct testGenObject *) malloc (sizeof(struct testGenObject));