Little endian support

cereal/car.capnp

@@ -294,6 +294,7 @@ struct CarParams {
     gm @4;
     hondaBosch @5;
     ford @6;
+    tesla @6;
   }
 
   # things about the car in the manual

selfdrive/boardd/boardd.cc

@@ -37,6 +37,8 @@
 #define SAFETY_ELM327 0xE327
 #define SAFETY_GM 3
 #define SAFETY_HONDA_BOSCH 4
+#define SAFETY_FORD 5
+#define SAFETY_TESLA 6
 #define SAFETY_TOYOTA_NOLIMITS 0x1336
 #define SAFETY_ALLOUTPUT 0x1337
 
@@ -105,6 +107,12 @@ void *safety_setter_thread(void *s) {
   case (int)cereal::CarParams::SafetyModels::HONDA_BOSCH:
     safety_setting = SAFETY_HONDA_BOSCH;
     break;
+  case (int)cereal::CarParams::SafetyModels::FORD:
+    safety_setting = SAFETY_FORD;
+    break;
+  case (int)cereal::CarParams::SafetyModels::TESLA:
+    safety_setting = SAFETY_TESLA;
+    break;
   default:
     LOGE("unknown safety model: %d", safety_model);
   }
@@ -672,4 +680,4 @@ int main() {
 
   libusb_close(dev_handle);
   libusb_exit(ctx);
-}
+}

selfdrive/can/common.h

@@ -48,6 +48,7 @@ struct Signal {
   int b1, b2, bo;
   bool is_signed;
   double factor, offset;
+  bool is_little_endian;
   SignalType type;
 };
 

selfdrive/can/dbc_template.cc

@@ -8,14 +8,19 @@ namespace {
 const Signal sigs_{{address}}[] = {
   {% for sig in sigs %}
     {
-      {% set b1 = (sig.start_bit//8)*8  + (-sig.start_bit-1) % 8 %}
+      {% if sig.is_little_endian %}
+        {% set b1 = sig.start_bit %}
+      {% else %}
+        {% set b1 = (sig.start_bit//8)*8  + (-sig.start_bit-1) % 8 %}
+      {% endif %}
       .name = "{{sig.name}}",
       .b1 = {{b1}},
       .b2 = {{sig.size}},
       .bo = {{64 - (b1 + sig.size)}},
       .is_signed = {{"true" if sig.is_signed else "false"}},
       .factor = {{sig.factor}},
       .offset = {{sig.offset}},
+      .is_little_endian = {{"true" if sig.is_little_endian else "false"}},
       {% if checksum_type == "honda" and sig.name == "CHECKSUM" %}
       .type = SignalType::HONDA_CHECKSUM,
       {% elif checksum_type == "honda" and sig.name == "COUNTER" %}

selfdrive/can/parser.cc

@@ -64,6 +64,17 @@ uint64_t read_u64_be(const uint8_t* v) {
           | (uint64_t)v[7]);
 }
 
+uint64_t read_u64_le(const uint8_t* v) {
+  return ((uint64_t)v[0] 
+          | ((uint64_t)v[1] << 8)
+          | ((uint64_t)v[2] << 16)
+          | ((uint64_t)v[3] << 24)
+          | ((uint64_t)v[4] << 32)
+          | ((uint64_t)v[5] << 40)
+          | ((uint64_t)v[6] << 48)
+          | ((uint64_t)v[7] << 56));
+}
+
 
 struct MessageState {
   uint32_t address;
@@ -82,8 +93,14 @@ struct MessageState {
   bool parse(uint64_t sec, uint16_t ts_, uint64_t dat) {
     for (int i=0; i < parse_sigs.size(); i++) {
       auto& sig = parse_sigs[i];
+      int64_t tmp;
 
-      int64_t tmp = (dat >> sig.bo) & ((1ULL << sig.b2)-1);
+      if (sig.is_little_endian){
+        tmp = (dat >> sig.b1) & ((1ULL << sig.b2)-1);  
+      } else {
+        tmp = (dat >> sig.bo) & ((1ULL << sig.b2)-1);
+      }
+
       if (sig.is_signed) {
         tmp -= (tmp >> (sig.b2-1)) ? (1ULL << sig.b2) : 0; //signed
       }
@@ -220,6 +237,7 @@ class CANParser {
 
   void UpdateCans(uint64_t sec, const capnp::List<cereal::CanData>::Reader& cans) {
       int msg_count = cans.size();
+      uint64_t p;
 
       DEBUG("got %d messages\n", msg_count);
 
@@ -240,7 +258,13 @@ class CANParser {
         uint8_t dat[8] = {0};
         memcpy(dat, cmsg.getDat().begin(), cmsg.getDat().size());
 
-        uint64_t p = read_u64_be(dat);
+        // Assumes all signals in the message are of the same type (little or big endian)
+        auto& sig = message_states[cmsg.getAddress()].parse_sigs[0];
+        if (sig.is_little_endian) {
+            p = read_u64_le(dat);
+        } else {
+            p = read_u64_be(dat);
+        }
 
         DEBUG("  proc %X: %llx\n", cmsg.getAddress(), p);