Revert "autodetect tg backend (#37778)"

This reverts commit 21538e5a09.

selfdrive/modeld/SConscript

@@ -1,9 +1,6 @@
-import glob
-import json
 import os
-from SCons.Script import Value
+import glob
 from openpilot.common.file_chunker import chunk_file, get_chunk_paths
-from tinygrad import Device
 
 Import('env', 'arch')
 chunker_file = File("#common/file_chunker.py")
@@ -16,51 +13,31 @@ tinygrad_files = ["#"+x for x in glob.glob(env.Dir("#tinygrad_repo").relpath + "
 def estimate_pickle_max_size(onnx_size):
   return 1.2 * onnx_size  + 10 * 1024 * 1024  # 20% + 10MB is plenty
 
+# compile warp
 # THREADS=0 is need to prevent bug: https://github.com/tinygrad/tinygrad/issues/14689
-# get fastest TG config
-available = set(Device.get_available_devices())
-if 'CUDA' in available:
-  tg_backend = 'CUDA'
-  tg_flags = f'DEV={tg_backend}'
-elif 'QCOM' in available:
-  tg_backend = 'QCOM'
-  tg_flags = f'DEV={tg_backend} FLOAT16=1 NOLOCALS=1 JIT_BATCH_SIZE=0'
-else:
-  tg_backend = 'CPU'
-  tg_flags = f'DEV={tg_backend} THREADS=0'
-
-def write_tg_compiled_flags(target, source, env):
-  with open(str(target[0]), "w") as f:
-    json.dump({"DEV": tg_backend}, f)
-    f.write("\n")
-
-compiled_flags_node = lenv.Command(
-  File("models/tg_compiled_flags.json").abspath,
-  tinygrad_files + [Value(tg_backend)],
-  write_tg_compiled_flags,
-)
-
-# tinygrad calls brew which needs a $HOME in the env
-mac_brew_string = f'HOME={os.path.expanduser("~")}' if arch == 'Darwin' else ''
+tg_flags = {
+    'larch64': 'DEV=QCOM FLOAT16=1 NOLOCALS=1 JIT_BATCH_SIZE=0',
+    'Darwin': f'DEV=CPU THREADS=0 HOME={os.path.expanduser("~")}', # tinygrad calls brew which needs a $HOME in the env
+}.get(arch, 'DEV=CPU:LLVM THREADS=0')
 
 # Get model metadata
 for model_name in ['driving_vision', 'driving_off_policy', 'driving_on_policy', 'dmonitoring_model']:
   fn = File(f"models/{model_name}").abspath
   script_files = [File(Dir("#selfdrive/modeld").File("get_model_metadata.py").abspath)]
-  cmd = f'{tg_flags} {mac_brew_string} python3 {Dir("#selfdrive/modeld").abspath}/get_model_metadata.py {fn}.onnx'
-  lenv.Command(fn + "_metadata.pkl", [fn + ".onnx"] + tinygrad_files + script_files + [compiled_flags_node], cmd)
+  cmd = f'{tg_flags} python3 {Dir("#selfdrive/modeld").abspath}/get_model_metadata.py {fn}.onnx'
+  lenv.Command(fn + "_metadata.pkl", [fn + ".onnx"] + tinygrad_files + script_files, cmd)
 
 image_flag = {
      'larch64': 'IMAGE=2',
 }.get(arch, 'IMAGE=0')
 script_files = [File(Dir("#selfdrive/modeld").File("compile_warp.py").abspath)]
-compile_warp_cmd = f'{tg_flags} {mac_brew_string} python3 {Dir("#selfdrive/modeld").abspath}/compile_warp.py '
+compile_warp_cmd = f'{tg_flags} python3 {Dir("#selfdrive/modeld").abspath}/compile_warp.py '
 from openpilot.common.transformations.camera import _ar_ox_fisheye, _os_fisheye
 warp_targets = []
 for cam in [_ar_ox_fisheye, _os_fisheye]:
   w, h = cam.width, cam.height
   warp_targets += [File(f"models/warp_{w}x{h}_tinygrad.pkl").abspath, File(f"models/dm_warp_{w}x{h}_tinygrad.pkl").abspath]
-lenv.Command(warp_targets, tinygrad_files + script_files + [compiled_flags_node], compile_warp_cmd)
+lenv.Command(warp_targets, tinygrad_files + script_files, compile_warp_cmd)
 
 def tg_compile(flags, model_name):
   pythonpath_string = 'PYTHONPATH="${PYTHONPATH}:' + env.Dir("#tinygrad_repo").abspath + '"'
@@ -70,7 +47,7 @@ def tg_compile(flags, model_name):
   chunk_targets = get_chunk_paths(pkl, estimate_pickle_max_size(os.path.getsize(onnx_path)))
   compile_node = lenv.Command(
     pkl,
-    [onnx_path] + tinygrad_files + [chunker_file, compiled_flags_node],
+    [onnx_path] + tinygrad_files + [chunker_file],
     f'{pythonpath_string} {flags} {image_flag} python3 {Dir("#tinygrad_repo").abspath}/examples/openpilot/compile3.py {fn}.onnx {pkl}',
   )
   def do_chunk(target, source, env):