]> rtime.felk.cvut.cz Git - can-benchmark.git/blobdiff - latester/latester.c
latester: Add partial support for CRC calculation
[can-benchmark.git] / latester / latester.c
index b7bb38b49bea7489d0bbe3a08d060155dc6e98d0..d09b1ab1a3027fedf670a657e4f6ee348306d10a 100644 (file)
@@ -1,6 +1,6 @@
 /**************************************************************************/
 /* CAN latency tester                                                     */
-/* Copyright (C) 2010 Michal Sojka, DCE FEE CTU Prague                    */
+/* Copyright (C) 2010, 2011 Michal Sojka, DCE FEE CTU Prague                    */
 /* License: GPLv2                                                        */
 /**************************************************************************/
 
@@ -133,7 +133,7 @@ void sprint_canframe(char *buf , struct can_frame *cf, int sep) {
                }
 }
 
-static inline struct msg_info *frame2info(struct can_frame *frame)
+static inline uint16_t frame_index(struct can_frame *frame)
 {
        uint16_t idx;
        if (frame->can_dlc >= 2) {
@@ -144,7 +144,12 @@ static inline struct msg_info *frame2info(struct can_frame *frame)
 
                error(1, 0, "%s error", __FUNCTION__);
        }
-       return &msg_infos[idx];
+       return idx;
+}
+
+static inline struct msg_info *frame2info(struct can_frame *frame)
+{
+       return &msg_infos[frame_index(frame)];
 }
 
 static inline char *tstamp_str(const void *ctx, struct timespec *tstamp)
@@ -153,6 +158,139 @@ static inline char *tstamp_str(const void *ctx, struct timespec *tstamp)
                               tstamp->tv_sec, tstamp->tv_nsec/1000);
 }
 
+/* Functions and types for CRC checks.
+ *
+ * Generated on Wed Sep 21 22:30:11 2011,
+ * by pycrc v0.7.8, http://www.tty1.net/pycrc/
+ * using the configuration:
+ *    Width        = 15
+ *    Poly         = 0x4599
+ *    XorIn        = 0x0000
+ *    ReflectIn    = False
+ *    XorOut       = 0x0000
+ *    ReflectOut   = False
+ *    Algorithm    = table-driven
+ *****************************************************************************/
+typedef uint16_t crc_t;
+
+static const crc_t crc_table[2] = {
+    0x0000, 0x4599
+};
+
+crc_t crc_update(crc_t crc, uint32_t data, size_t bit_len)
+{
+    unsigned int tbl_idx;
+/*     crc_t bc = crc; */
+/*     uint32_t bd = data; */
+/*     size_t bl = bit_len; */
+
+    while (bit_len--) {
+        tbl_idx = (crc >> 14) ^ (data >> 31);
+        crc = crc_table[tbl_idx & 0x01] ^ (crc << 1);
+       data <<= 1;
+    }
+    crc = crc & 0x7fff;
+/*     printf("crc: 0x%04x -> 0x%04x  data: 0x%08x  len: %d\n", */
+/*        bc, crc, bd, bl); */
+    return crc;
+}
+
+unsigned calc_stuff_bits(struct can_frame *frame) {
+       uint32_t bitmap[4];
+       unsigned start = 0, end;
+       uint32_t mask, ones = 0, basemask = 0xf8000000;
+       unsigned stuffed = 0;
+       memset(bitmap, 0, sizeof(bitmap));
+       crc_t crc = 0;
+       uint32_t crcx;
+
+       if (frame->can_id & CAN_EFF_FLAG) {
+               bitmap[0] =
+                       ((frame->can_id & CAN_EFF_MASK) >> 25);
+               bitmap[1] =
+                       ((frame->can_id & CAN_EFF_MASK) >> 18) << 25    |
+                       3 << 23                                         |
+                       ((frame->can_id & CAN_EFF_MASK) & 0x3ffff) << 7 |
+                       (!!(frame->can_id & CAN_RTR_FLAG)) << 6         |
+                       0 << 4                                          |
+                       frame->can_dlc & 0xf;
+               bitmap[2] = htonl(((uint32_t*)frame->data)[0]);
+               bitmap[3] = htonl(((uint32_t*)frame->data)[1]);
+               start = 27;
+               end = 64 + 8*frame->can_dlc;
+               crc = crc_update(crc, bitmap[0] << start, 32-start);
+               crc = crc_update(crc, bitmap[1], 32);
+               crc = crc_update(crc, bitmap[2], end - 64 > 32 ? 32 : end - 64);
+               crc = crc_update(crc, bitmap[3], end > 96 ? end - 96 : 0);
+               crcx = (uint32_t)htons(crc) << 17;
+               if (frame->can_dlc < 4)
+                       bitmap[2] |= crcx >> (frame->can_dlc*8);
+               if (frame->can_dlc = 3)
+                       bitmap[3] |= crcx << 8;
+               if (frame->can_dlc >= 4)
+                       bitmap[3] |= crcx >> (frame->can_dlc*8);
+       } else {
+               bitmap[0] =
+                       (frame->can_id << 7) |
+                       (!!(frame->can_id & CAN_RTR_FLAG)) << 6 |
+                       0 << 4                                  |
+                       frame->can_dlc & 0xf;
+               bitmap[1] = htonl(((uint32_t*)frame->data)[0]);
+               bitmap[2] = htonl(((uint32_t*)frame->data)[1]);
+               start = 13;
+               end = 32 + 8*frame->can_dlc;
+       }
+       /* TODO: Calc stuff bits in CRC */
+       while (start < end) {
+               mask = basemask >> (start & 0x1f);
+               while (1) {
+                       ones = ones ? mask : 0;
+                       uint32_t chunk = (bitmap[start >> 5] & mask) ^ ones;
+                       //printf("start=%d  bitmap=0x%08x  mask=0x%08x  ones=0x%08x  chunk=0x%08x\n", start, bitmap[start >> 5], mask, ones, chunk);
+                       if (chunk) {
+                               unsigned change = __builtin_clz(chunk);
+                               start = start & ~0x1f | change;
+                               basemask = 0xf8000000;
+                       } else {
+                               unsigned oldstart = start;
+                               start += __builtin_popcount(mask);
+                               mask = (oldstart & 0x1f) ? basemask << (-oldstart & 0x1f) : 0;
+                               //printf("oldstart=%d  shl=%d  mask=0x%08x\n", oldstart, -oldstart & 0x1f, mask);
+                               if (mask && start < end)
+                                       continue;
+                               if (start <= end && !mask) {
+                                       stuffed++;
+                                       basemask = 0xf0000000;
+                                       //printf("stuffed %d\n", !ones);
+                               }
+                       }
+                       break;
+               }
+               ones = !ones;
+       }
+       //printf ("STUFFED %d BITS\n", stuffed);
+}
+
+unsigned calc_frame_txtime(struct can_frame *frame) {
+       return calc_stuff_bits(frame) +
+               1 +             /* SOF */
+               11 +            /* ID A */
+               ((frame->can_id & CAN_EFF_FLAG) ?
+                1 +            /* SRR */
+                1 +            /* IDE */
+                18 +           /* ID B */
+                1 +            /* RTR */
+                2              /* r1, r0 */
+                :
+                1 +            /* rtr */
+                2) +           /* ide, r0 */
+               4 +             /* dlc */
+               8*frame->can_dlc +
+               15 +            /* CRC */
+               3 +             /* CRC del, ACK, ACK del */
+               7;              /* EOF */
+}
+
 void msg_info_print(FILE *f, struct msg_info *mi)
 {
        struct timespec diff;
@@ -168,20 +306,22 @@ void msg_info_print(FILE *f, struct msg_info *mi)
 
        switch (num_interfaces) {
        case 2:
-               fprintf(f, "%ld: %s %s -> %s (%s) %s = %s (%s)\n",
+               fprintf(f, "%ld: %s %s -> %s (%s) %s = %s (%s) %d\n",
                        num, S(mi->ts_sent), sent, S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
-                      DIFF(mi->ts_sent, mi->ts_rx_final_kern),
-                      DIFF(mi->ts_sent, mi->ts_rx_final));
+                       DIFF(mi->ts_sent, mi->ts_rx_final_kern),
+                       DIFF(mi->ts_sent, mi->ts_rx_final),
+                       calc_frame_txtime(&mi->received));
                break;
        case 3:
-               fprintf(f, "%ld: %s %s -> %s (%s) -> %s (%s) %s = %s (%s), %s (%s)\n",
+               fprintf(f, "%ld: %s %s -> %s (%s) -> %s (%s) %s = %s (%s), %s (%s) %d\n",
                        num, S(mi->ts_sent), sent,
                        S(mi->ts_rx_onwire_kern), S(mi->ts_rx_onwire),
                        S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
                        DIFF(mi->ts_sent, mi->ts_rx_onwire_kern),
                        DIFF(mi->ts_sent, mi->ts_rx_onwire),
                        DIFF(mi->ts_rx_onwire_kern, mi->ts_rx_final_kern),
-                       DIFF(mi->ts_rx_onwire, mi->ts_rx_final));
+                       DIFF(mi->ts_rx_onwire, mi->ts_rx_final),
+                       calc_frame_txtime(&mi->received));
                break;
        }
 #undef S
@@ -606,13 +746,15 @@ void *measure_thread(void *arg)
                        }
                        pfd[0].revents = 0;
 
-                       if (num_interfaces == 3 && pfd[1].revents != 0) {
+                       if (num_interfaces == 3 && pfd[1].revents & POLLIN) {
                                process_on_wire_rx(pfd[1].fd);
                                pfd[1].revents = 0;
                        }
+                       if (num_interfaces == 3 && pfd[1].revents & ~POLLIN)
+                               error(1, 0, "Unexpected pfd[1].revents: 0x%04x\n", pfd[1].revents);
 
                        i = (num_interfaces == 2) ? 1 : 2;
-                       if (pfd[i].revents != 0) {
+                       if (pfd[i].revents & POLLIN) {
                                consecutive_timeouts = 0;
                                process_final_rx(pfd[i].fd);
                                msg_in_progress--;
@@ -622,6 +764,8 @@ void *measure_thread(void *arg)
                                        SEND();
                                }
                        }
+                       if (pfd[i].revents & ~POLLIN)
+                               error(1, 0, "Unexpected pfd[%d].revents: 0x%04x\n", pfd[i].revents);
                }
        }