hyundai canfd: bump steer max 270->324 (~+20%), rate_up 2->3, rate_down 3->5

Tucson (and other Hyundai CAN-FD HDA2 cars) get pinned to comma's
conservative steer ceiling of 270 in the CAN-FD branch of
selfdrive/car/hyundai/values.py and the matching panda safety limit
HYUNDAI_CANFD_STEERING_LIMITS. Comma's non-CAN-FD HKG default is 384;
PR commaai/openpilot#25723 merged 384 for HDA1 EV6/Ioniq 5 with
operator quote "max steer needed to be 384 to make basic turns."

Bumping to 324 (~+20%) keeps a safe margin under the proven 384
ceiling while giving enough headroom for moderate clover-style on-ramps
without the controller hitting the limit. Rate limits also nudged up
(2->3 up, 3->5 down) to match the slightly higher ceiling and reduce
ramp time / release lag; chose 5 instead of comma's 7 for delta_down to
keep release smoother. max_rt_delta scaled proportionally (112->134) so
the 250ms real-time check tracks the new ceiling.

Both files MUST stay in lockstep — panda safety enforces independently
and would reject larger commands if only one side was bumped. Panda
firmware re-flashes automatically on next pandad start because the
safety code hash changed.

References:
  https://github.com/commaai/openpilot/pull/25723   (HDA1 270->384)
  https://github.com/commaai/openpilot/issues/24122 (HKG torque blacklist)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

panda/board/safety/safety_hyundai_canfd.h

@@ -1,11 +1,16 @@
 #include "safety_hyundai_common.h"
 
 const SteeringLimits HYUNDAI_CANFD_STEERING_LIMITS = {
-  .max_steer = 270,
+  // CLEARPILOT: bumped from comma defaults (270/2/3/112) by ~20% so this Tucson HDA2
-  .max_rt_delta = 112,
+  // can hold modest curvature in place. Mirrors the rate-limit shape comma uses for
+  // its non-CAN-FD high-torque HKG default (384/3/7). Must stay in lockstep with
+  // STEER_MAX in selfdrive/car/hyundai/values.py — panda enforces independently and
+  // will reject larger commands if openpilot's value exceeds this.
+  .max_steer = 324,
+  .max_rt_delta = 134,
   .max_rt_interval = 250000,
-  .max_rate_up = 2,
+  .max_rate_up = 3,
-  .max_rate_down = 3,
+  .max_rate_down = 5,
   .driver_torque_allowance = 250,
   .driver_torque_factor = 2,
   .type = TorqueDriverLimited,

selfdrive/car/hyundai/values.py

@@ -27,12 +27,14 @@ class CarControllerParams:
     self.STEER_STEP = 1  # 100 Hz
 
     if CP.carFingerprint in CANFD_CAR:
-      self.STEER_MAX = 270
+      # CLEARPILOT: bumped from comma defaults (270/2/3) by ~20% — must stay in
+      # lockstep with HYUNDAI_CANFD_STEERING_LIMITS in panda/board/safety/safety_hyundai_canfd.h.
+      self.STEER_MAX = 324
       self.STEER_DRIVER_ALLOWANCE = 250
       self.STEER_DRIVER_MULTIPLIER = 2
       self.STEER_THRESHOLD = 250
-      self.STEER_DELTA_UP = 2
+      self.STEER_DELTA_UP = 3
-      self.STEER_DELTA_DOWN = 3
+      self.STEER_DELTA_DOWN = 5
 
     # To determine the limit for your car, find the maximum value that the stock LKAS will request.
     # If the max stock LKAS request is <384, add your car to this list.