Fixed crc issues

lte/include/lte/fec/crc.h

@@ -36,6 +36,7 @@
 #define LTE_CRC8	0x19B
 
 
+int init_crc(int lorder, unsigned long polynom);
 unsigned int crc(unsigned int crc, char *bufptr, int len,
 		int long_crc,unsigned int poly, int paste_word);
 

lte/lib/fec/src/crc.c

@@ -28,63 +28,152 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+#include "lte/utils/pack.h"
+
+#define _WITHMALLOC
 
 unsigned int cword;
+char *cdata;
+const unsigned long crcinit = 0x00000000; 	//initial CRC value
+const unsigned long crcxor = 0x00000000;	//final XOR value
+unsigned long crcmask;
+unsigned long crchighbit;
+unsigned long crctab[256]; 
+
+
+
 
-unsigned int icrc1(unsigned int crc, unsigned short onech,int long_crc,
+void gen_crc_table(int lorder, unsigned long poly) {
-		int left_shift,unsigned int poly)
-{
-  int i;
-  unsigned int tmp=(unsigned int) (crc ^ (onech << (long_crc >> 1) ));
 
-  for (i=0;i<left_shift;i++) {
+	int i, j, ord=(lorder-8);
-    if (tmp & (0x1<<(long_crc-1)))
+	unsigned long bit, crc;
-      tmp=(tmp<<1)^poly;
-    else
-      tmp <<= 1;
-  }
 
-  return tmp;
+	for (i=0; i<256; i++) {
+		crc = ((unsigned long)i)<<ord;
+		for (j=0; j<8; j++) {
+			bit = crc & crchighbit;
+			crc<<= 1;
+			if (bit) crc^= poly;
+		}			
+		crctab[i] = crc & crcmask;
+	}
 }
 
-unsigned int crc(unsigned int crc, char *bufptr, int len,
+
-		int long_crc,unsigned int poly, int paste_word) {
+unsigned long crctable (unsigned char* data, unsigned long length, int lorder) {
-
+
-  int i,k;
+	// Polynom lorders of 8, 16, 24 or 32.
-  unsigned int data;
+	unsigned long crc = crcinit;
-  int stop;
+
-  unsigned int ret;
+	while (length--) crc = (crc << 8) ^ crctab[ ((crc >> (lorder-8)) & 0xff) ^ *data++];
-
+	
-  cword=crc;
+	return((crc^crcxor)&crcmask);
-
-  k=0;
-  stop=0;
-  while(!stop) {
-    data=0;
-    for (i=0;i<long_crc/2;i++) {
-      if (bufptr[k] && k<len)
-        data|=(0x1<<(long_crc/2-1-i));
-      k++;
-      if (k==len) {
-        stop=1;
-        i++;
-        break;
-      }
-    }
-
-    cword=(unsigned int) (icrc1((unsigned int) (cword<<long_crc>>long_crc),
-    		data,long_crc,i,poly)<<long_crc)>>long_crc;
-  }
-
-  ret=cword;
-  if (paste_word) {
-    cword<<=32-long_crc;
-    for (i=0;i<long_crc;i++) {
-       bufptr[i+len]=((cword&(0x1<<31))>>31);
-       cword<<=1;
-    }
-  }
-  return (ret);
 }
 
+unsigned long reversecrcbit(unsigned int crc, unsigned int polynom, int lorder, int nbits) {
+
+	unsigned long m, rmask=0x1;
+
+	for(m=0; m<nbits; m++){	
+		if((rmask & crc) == 0x01 )crc = (crc ^ polynom)>>1;
+		else crc = crc >> 1;
+	}
+	return((crc^crcxor)&crcmask);
+}
+
+
+int init_crc(int lorder, unsigned long polynom){
+
+	unsigned long polyhighbit;
+
+	// Compute bit masks for whole CRC and CRC high bit
+	crcmask = ((((unsigned long)1<<(lorder-1))-1)<<1)|1;
+	polyhighbit=0xFFFFFFFF ^ (crcmask+1);
+	crchighbit = (unsigned long)1<<(lorder-1);
+
+	// Eliminate highest bit in polynom word
+	polynom=polynom & polyhighbit;  
+
+	// check parameters
+	if (lorder < 1 || lorder > 32) {
+		printf("ERROR, invalid order, it must be between 1..32.\n");
+		return(0);
+	}
+	if (lorder%8 != 0) {
+		printf("ERROR, invalid order=%d, it must be 8, 16, 24 or 32.\n", lorder);
+		return(0);
+	}
+	if (polynom != (polynom & crcmask)) {
+		printf("ERROR, invalid polynom.\n");
+		return(0);
+	}
+	if (crcinit != (crcinit & crcmask)) {
+		printf("ERROR, invalid crcinit.\n");
+		return(0);
+	}
+	if (crcxor != (crcxor & crcmask)) {
+		printf("ERROR, invalid crcxor.\n");
+		return(0);
+	}
+	// generate lookup table
+	gen_crc_table(lorder, polynom);
+
+	return(1);
+}
+
+#define MAX_LENGTH	8192
+
+unsigned int crc(unsigned int crc, char *bufptr, int len,
+		int long_crc, unsigned int poly, int paste_word) {
+
+	int i, len8, res8, a;
+#ifdef _WITHMALLOC
+	char *data0, *pter;
+
+	data0 = (char *)malloc(sizeof(char) * (len+long_crc)*2);
+	if (!data0) {
+		perror("malloc ERROR: Allocating memory for data pointer in crc() function");
+		return(-1);
+	}
+#endif
+#ifndef _WITHMALLOC
+	char data0[MAX_LENGTH], *pter;	
+
+	if((((len+long_crc)>>3) + 1) > MAX_LENGTH){
+		printf("ERROR: Not enough memory allocated\n");
+		return(-1);
+	}
+#endif
+	//# Pack bits into bytes 
+	len8=(len>>3);
+	res8=8-(len - (len8<<3));
+	if(res8>0)a=1;
+	else a=0;
+
+	// Zeroed additional bits
+	memset((char *)(bufptr+len),0,(32)*sizeof(char));
+
+	for(i=0; i<len8+a; i++){
+		pter=(char *)(bufptr+8*i);
+		data0[i]=(char)(unpack_bits(&pter, 8)&0xFF);
+	}
+	// Calculate CRC
+	pter=data0;
+	crc=crctable ((unsigned char *)pter, len8+a, long_crc);
+
+	// Reverse CRC res8 positions
+	if(a==1)crc=reversecrcbit(crc, poly, long_crc, res8);
+
+	// Add CRC
+	pter=(char *)(bufptr+len);
+	pack_bits(crc, &pter, long_crc);
+
+#ifdef _WITHMALLOC
+	free(data0);
+	data0=NULL;
+#endif
+	//Return CRC value
+	return crc;
+}
 

lte/lib/fec/test/CMakeLists.txt

@@ -43,9 +43,9 @@ ADD_TEST(viterbi_1000_4 viterbi_test -n 100 -s 1 -l 1000 -k 7 -t -e 4.5)
 ADD_EXECUTABLE(crc_test crc_test.c)
 TARGET_LINK_LIBRARIES(crc_test lte)
 
-ADD_TEST(crc_24A crc_test -n 5000 -l 24 -p 0x1864CFB -s 1)
+ADD_TEST(crc_24A crc_test -n 5001 -l 24 -p 0x1864CFB -s 1)
-ADD_TEST(crc_24B crc_test -n 5000 -l 24 -p 0x1800063 -s 1)
+ADD_TEST(crc_24B crc_test -n 5001 -l 24 -p 0x1800063 -s 1)
-ADD_TEST(crc_16 crc_test -n 5000 -l 16 -p 0x11021 -s 1)
+ADD_TEST(crc_16 crc_test -n 5001 -l 16 -p 0x11021 -s 1)
-ADD_TEST(crc_8 crc_test -n 5000 -l 8 -p 0x19B -s 1)
+ADD_TEST(crc_8 crc_test -n 5001 -l 8 -p 0x19B -s 1)
 
  

lte/lib/fec/test/crc_test.c

@@ -35,12 +35,11 @@
 #include <time.h>
 
 #include "lte.h"
-
 #include "crc_test.h"
 
-int num_bits = 1000, crc_length = 16;
+int num_bits = 5000, crc_length = 24;
-unsigned int crc_poly = 0x11021;
+unsigned int crc_poly = 0x1864CFB;
-unsigned int seed = 0;
+unsigned int seed = 1;
 
 
 void usage(char *prog) {
@@ -81,7 +80,7 @@ int main(int argc, char **argv) {
 
 	parse_args(argc, argv);
 
-	data = malloc(sizeof(char) * (num_bits+crc_length));
+	data = malloc(sizeof(char) * (num_bits+crc_length)*2);
 	if (!data) {
 		perror("malloc");
 		exit(-1);
@@ -97,6 +96,9 @@ int main(int argc, char **argv) {
 		data[i] = rand()%2;
 	}
 
+	//Initialize crc params and tables
+	if(!init_crc(crc_length, crc_poly))exit(0);
+
 	// generate CRC word
 	crc_word = crc(0, data, num_bits, crc_length, crc_poly, 1);
 

lte/lib/fec/test/crc_test.h

@@ -39,10 +39,15 @@ typedef struct {
 
 
 static expected_word_t expected_words[] = {
-		{5000, 24, LTE_CRC24A, 1, 0x4D0836},		// LTE CRC24A (36.212 Sec 5.1.1)
+	/*	{5000, 24, LTE_CRC24A, 1, 0x4D0836},		// LTE CRC24A (36.212 Sec 5.1.1)
 		{5000, 24, LTE_CRC24B, 1, 0x9B68F8},		// LTE CRC24B
-		{5000, 16, LTE_CRC16, 1, 0xBFFA},  		// LTE CRC16
+		{5000, 16, LTE_CRC16, 1, 0xBFFA},  		// LTE CRC16: 0xBFFA
-		{5000, 8, LTE_CRC8, 1, 0xF8},				// LTE CRC8
+		{5000, 8, LTE_CRC8, 1, 0xF8},			// LTE CRC8 0xF8
+	*/
+		{5001, 24, LTE_CRC24A, 1, 0x1C5C97},		// LTE CRC24A (36.212 Sec 5.1.1)
+		{5001, 24, LTE_CRC24B, 1, 0x36D1F0},		// LTE CRC24B
+		{5001, 16, LTE_CRC16, 1, 0x7FF4},  		// LTE CRC16: 0x7FF4
+		{5001, 8, LTE_CRC8, 1,  0xF0},			// LTE CRC8 0xF8
 
 		{-1, -1, 0, 0, 0}
 };