Fix CRC for more sizes

lib/include/srslte/phy/fec/crc.h

@@ -47,11 +47,20 @@ SRSLTE_API uint32_t srslte_crc_attach_byte(srslte_crc_t* h, uint8_t* data, int l
 static inline void srslte_crc_checksum_put_byte(srslte_crc_t* h, uint8_t byte)
 {
 
-  // Polynom order 8, 16, 24 or 32 only.
-  int      ord = h->order - 8;
   uint64_t crc = h->crcinit;
 
-  crc        = (crc << 8) ^ h->table[((crc >> (ord)) & 0xff) ^ byte];
+  uint32_t idx;
+  if (h->order > 8) {
+    // For more than 8 bits
+    uint32_t ord = h->order - 8U;
+    idx          = ((crc >> (ord)) & 0xffU) ^ byte;
+  } else {
+    // For 8 bits or less
+    uint32_t ord = 8U - h->order;
+    idx          = ((crc << (ord)) & 0xffU) ^ byte;
+  }
+
+  crc        = (crc << 8U) ^ h->table[idx];
   h->crcinit = crc;
 }
 

lib/src/phy/fec/crc.c

@@ -10,29 +10,27 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
 #include "srslte/phy/fec/crc.h"
 #include "srslte/phy/utils/bit.h"
 #include "srslte/phy/utils/debug.h"
 
-void gen_crc_table(srslte_crc_t* h)
+static void gen_crc_table(srslte_crc_t* h)
 {
+  uint32_t pad        = (h->order < 8) ? (8 - h->order) : 0;
+  uint32_t ord        = h->order + pad - 8;
+  uint32_t polynom    = h->polynom << pad;
+  uint32_t crchighbit = h->crchighbit << pad;
 
-  int      i, j, ord = (h->order - 8);
-  uint64_t bit, crc;
-
-  for (i = 0; i < 256; i++) {
-    crc = ((uint64_t)i) << ord;
-    for (j = 0; j < 8; j++) {
-      bit = crc & h->crchighbit;
-      crc <<= 1;
-      if (bit)
-        crc ^= h->polynom;
+  for (uint32_t i = 0; i < 256; i++) {
+    uint64_t crc = ((uint64_t)i) << ord;
+    for (uint32_t j = 0; j < 8; j++) {
+      bool bit = crc & crchighbit;
+      crc <<= 1U;
+      if (bit) {
+        crc ^= polynom;
+      }
     }
-    h->table[i] = crc & h->crcmask;
+    h->table[i] = (crc >> pad) & h->crcmask;
   }
 }
 
@@ -73,12 +71,6 @@ int srslte_crc_init(srslte_crc_t* h, uint32_t crc_poly, int crc_order)
   h->crcmask    = ((((uint64_t)1 << (h->order - 1)) - 1) << 1) | 1;
   h->crchighbit = (uint64_t)1 << (h->order - 1);
 
-  // check parameters
-  if (h->order % 8 != 0) {
-    ERROR("ERROR(invalid order=%d, it must be 8, 16, 24 or 32.\n", h->order);
-    return -1;
-  }
-
   if (srslte_crc_set_init(h, h->crcinit)) {
     ERROR("Error setting CRC init word\n");
     return -1;

lib/src/phy/fec/test/CMakeLists.txt

@@ -17,5 +17,7 @@ add_test(crc_24A crc_test -n 5001 -l 24 -p 0x1864CFB -s 1)
 add_test(crc_24B crc_test -n 5001 -l 24 -p 0x1800063 -s 1)
 add_test(crc_16 crc_test -n 5001 -l 16 -p 0x11021 -s 1)
 add_test(crc_8 crc_test -n 5001 -l 8 -p 0x19B -s 1)
+add_test(crc_11 crc_test -n 30 -l 11 -p 0xE21 -s 1)
+add_test(crc_6 crc_test -n 20 -l 6 -p 0x61 -s 1)
 
  

lib/src/phy/fec/test/crc_test.c

@@ -32,12 +32,13 @@ void usage(char* prog)
   printf("\t-l crc_length [Default %d]\n", crc_length);
   printf("\t-p crc_poly (Hex) [Default 0x%x]\n", crc_poly);
   printf("\t-s seed [Default 0=time]\n");
+  printf("\t-v [set srslte_verbose to debug, default none]\n");
 }
 
 void parse_args(int argc, char** argv)
 {
   int opt;
-  while ((opt = getopt(argc, argv, "nlps")) != -1) {
+  while ((opt = getopt(argc, argv, "nlpsv")) != -1) {
     switch (opt) {
       case 'n':
         num_bits = (int)strtol(argv[optind], NULL, 10);
@@ -51,6 +52,9 @@ void parse_args(int argc, char** argv)
       case 's':
         seed = (uint32_t)strtoul(argv[optind], NULL, 0);
         break;
+      case 'v':
+        srslte_verbose++;
+        break;
       default:
         usage(argv[0]);
         exit(-1);
@@ -83,6 +87,11 @@ int main(int argc, char** argv)
     data[i] = rand() % 2;
   }
 
+  if (SRSLTE_DEBUG_ENABLED && srslte_verbose >= SRSLTE_VERBOSE_INFO && !handler_registered) {
+    INFO("data=");
+    srslte_vec_fprint_b(stdout, data, num_bits);
+  }
+
   // Initialize CRC params and tables
   if (srslte_crc_init(&crc_p, crc_poly, crc_length)) {
     exit(-1);
@@ -91,6 +100,8 @@ int main(int argc, char** argv)
   // generate CRC word
   crc_word = srslte_crc_checksum(&crc_p, data, num_bits);
 
+  INFO("checksum=%x\n", crc_word);
+
   free(data);
 
   // check if generated word is as expected

lib/src/phy/fec/test/crc_test.h

@@ -29,6 +29,8 @@ static expected_word_t expected_words[] = {
     {5001, 24, SRSLTE_LTE_CRC24B, 1, 0x36D1F0}, // LTE CRC24B
     {5001, 16, SRSLTE_LTE_CRC16, 1, 0x7FF4},    // LTE CRC16: 0x7FF4
     {5001, 8, SRSLTE_LTE_CRC8, 1, 0xF0},        // LTE CRC8 0xF8
+    {30, 11, SRSLTE_LTE_CRC11, 1, 0x114},       // NR CRC11 0x114
+    {20, 6, SRSLTE_LTE_CRC6, 1, 0x1F},          // NR CRC6 0x1F
 
     {-1, -1, 0, 0, 0}};