GM pedal interceptor

board/safety/safety_gm.h

@@ -27,6 +27,11 @@ const LongitudinalLimits *gm_long_limits;
 
 const int GM_STANDSTILL_THRSLD = 10;  // 0.311kph
 
+// panda interceptor threshold needs to be equivalent to openpilot threshold to avoid controls mismatches
+// If thresholds are mismatched then it is possible for panda to see the gas fall and rise while openpilot is in the pre-enabled state
+const int GM_GAS_INTERCEPTOR_THRESHOLD = 515;
+#define GM_GET_INTERCEPTOR(msg) (((GET_BYTE((msg), 0) << 8) + GET_BYTE((msg), 1) + (GET_BYTE((msg), 2) << 8) + GET_BYTE((msg), 3)) / 2U) // avg between 2 tracks
+
 const CanMsg GM_ASCM_TX_MSGS[] = {{0x180, 0, 4}, {0x409, 0, 7}, {0x40A, 0, 7}, {0x2CB, 0, 8}, {0x370, 0, 6},  // pt bus
                                   {0xA1, 1, 7}, {0x306, 1, 8}, {0x308, 1, 7}, {0x310, 1, 2},   // obs bus
                                   {0x315, 2, 5},  // ch bus
@@ -38,6 +43,9 @@ const CanMsg GM_CAM_TX_MSGS[] = {{0x180, 0, 4},  // pt bus
 const CanMsg GM_CAM_LONG_TX_MSGS[] = {{0x180, 0, 4}, {0x315, 0, 5}, {0x2CB, 0, 8}, {0x370, 0, 6},  // pt bus
                                       {0x184, 2, 8}};  // camera bus
 
+const CanMsg GM_CAM_INTERCEPTOR_TX_MSGS[] = {{0x180, 0, 4}, {0x315, 0, 5}, {0x2CB, 0, 8}, {0x370, 0, 6}, {0x200, 0, 6},  // pt bus
+                                             {0x184, 2, 8}, {0x1E1, 2, 7}};  // camera bus
+
 // TODO: do checksum and counter checks. Add correct timestep, 0.1s for now.
 RxCheck gm_rx_checks[] = {
   {.msg = {{0x184, 0, 8, .frequency = 10U}, { 0 }, { 0 }}},
@@ -52,6 +60,7 @@ RxCheck gm_rx_checks[] = {
 
 const uint16_t GM_PARAM_HW_CAM = 1;
 const uint16_t GM_PARAM_HW_CAM_LONG = 2;
+const uint16_t GM_PARAM_GAS_INTERCEPTOR = 4;
 
 enum {
   GM_BTN_UNPRESS = 1,
@@ -112,7 +121,9 @@ static void gm_rx_hook(CANPacket_t *to_push) {
     }
 
     if (addr == 0x1C4) {
-      gas_pressed = GET_BYTE(to_push, 5) != 0U;
+      if (!enable_gas_interceptor) {
+        gas_pressed = GET_BYTE(to_push, 5) != 0U;
+      }
 
       // enter controls on rising edge of ACC, exit controls when ACC off
       if (gm_pcm_cruise) {
@@ -125,6 +136,13 @@ static void gm_rx_hook(CANPacket_t *to_push) {
       regen_braking = (GET_BYTE(to_push, 0) >> 4) != 0U;
     }
 
+    // Pedal Interceptor
+    if ((addr == 0x201) && enable_gas_interceptor) {
+      int gas_interceptor = GM_GET_INTERCEPTOR(to_push);
+      gas_pressed = gas_interceptor > GM_GAS_INTERCEPTOR_THRESHOLD;
+      gas_interceptor_prev = gas_interceptor;
+    }
+
     bool stock_ecu_detected = (addr == 0x180);  // ASCMLKASteeringCmd
 
     // Check ASCMGasRegenCmd only if we're blocking it
@@ -160,6 +178,13 @@ static bool gm_tx_hook(CANPacket_t *to_send) {
     }
   }
 
+  // GAS: safety check (interceptor)
+  if (addr == 0x200) {
+    if (longitudinal_interceptor_checks(to_send)) {
+      tx = 0;
+    }
+  }
+
   // GAS/REGEN: safety check
   if (addr == 0x2CB) {
     bool apply = GET_BIT(to_send, 0U) != 0U;
@@ -176,10 +201,10 @@ static bool gm_tx_hook(CANPacket_t *to_send) {
   }
 
   // BUTTONS: used for resume spamming and cruise cancellation with stock longitudinal
-  if ((addr == 0x1E1) && gm_pcm_cruise) {
+  if ((addr == 0x1E1) && (gm_pcm_cruise || enable_gas_interceptor)) {
     int button = (GET_BYTE(to_send, 5) >> 4) & 0x7U;
 
-    bool allowed_cancel = (button == 6) && cruise_engaged_prev;
+    bool allowed_cancel = (button == GM_BTN_CANCEL) && cruise_engaged_prev;
     if (!allowed_cancel) {
       tx = false;
     }
@@ -224,14 +249,21 @@ static safety_config gm_init(uint16_t param) {
   } else {
   }
 
+  enable_gas_interceptor = GET_FLAG(param, GM_PARAM_GAS_INTERCEPTOR);
 #ifdef ALLOW_DEBUG
   gm_cam_long = GET_FLAG(param, GM_PARAM_HW_CAM_LONG);
 #endif
   gm_pcm_cruise = (gm_hw == GM_CAM) && !gm_cam_long;
 
   safety_config ret = BUILD_SAFETY_CFG(gm_rx_checks, GM_ASCM_TX_MSGS);
   if (gm_hw == GM_CAM) {
-    ret = gm_cam_long ? BUILD_SAFETY_CFG(gm_rx_checks, GM_CAM_LONG_TX_MSGS) : BUILD_SAFETY_CFG(gm_rx_checks, GM_CAM_TX_MSGS);
+    if (enable_gas_interceptor) {
+      ret = BUILD_SAFETY_CFG(gm_rx_checks, GM_CAM_INTERCEPTOR_TX_MSGS);
+    } else if (gm_cam_long) {
+      ret = BUILD_SAFETY_CFG(gm_rx_checks, GM_CAM_LONG_TX_MSGS);
+    } else {
+      ret = BUILD_SAFETY_CFG(gm_rx_checks, GM_CAM_TX_MSGS);
+    }
   }
   return ret;
 }

python/__init__.py

@@ -227,6 +227,7 @@ class Panda:
 
   FLAG_GM_HW_CAM = 1
   FLAG_GM_HW_CAM_LONG = 2
+  FLAG_GM_GAS_INTERCEPTOR = 4
 
   FLAG_FORD_LONG_CONTROL = 1
   FLAG_FORD_CANFD = 2

tests/safety/common.py

@@ -849,7 +849,7 @@ def test_tx_hook_on_wrong_safety_mode(self):
               continue
             if {attr, current_test}.issubset({'TestVolkswagenPqSafety', 'TestVolkswagenPqStockSafety', 'TestVolkswagenPqLongSafety'}):
               continue
-            if {attr, current_test}.issubset({'TestGmCameraSafety', 'TestGmCameraLongitudinalSafety'}):
+            if {attr, current_test}.issubset({'TestGmCameraSafety', 'TestGmCameraLongitudinalSafety', 'TestGmCameraGasInterceptorSafety'}):
               continue
             if attr.startswith('TestFord') and current_test.startswith('TestFord'):
               continue

tests/safety/test_gm.py

@@ -225,5 +225,25 @@ def setUp(self):
     self.safety.init_tests()
 
 
+class TestGmCameraGasInterceptorSafety(common.GasInterceptorSafetyTest, TestGmCameraLongitudinalSafety):
+  INTERCEPTOR_THRESHOLD = 515
+
+  def setUp(self):
+    self.packer = CANPackerPanda("gm_global_a_powertrain_generated")
+    self.packer_chassis = CANPackerPanda("gm_global_a_chassis")
+    self.safety = libpanda_py.libpanda
+    self.safety.set_safety_hooks(Panda.SAFETY_GM, Panda.FLAG_GM_HW_CAM | Panda.FLAG_GM_HW_CAM_LONG | Panda.FLAG_GM_GAS_INTERCEPTOR)
+    self.safety.init_tests()
+
+  def _interceptor_user_gas(self, gas):
+    # GM DBC file scales the GAS_SENSOR values
+    to_send = common.make_msg(0, 0x201, 6)
+    to_send[0].data[0] = (gas & 0xFF00) >> 8
+    to_send[0].data[1] = gas & 0xFF
+    to_send[0].data[2] = (gas & 0xFF00) >> 8
+    to_send[0].data[3] = gas & 0xFF
+    return to_send
+
+
 if __name__ == "__main__":
   unittest.main()