T3K Falcon40b perplexity tests (tenstorrent#12313)

#0: Skip decode seqlen>128 perplexity tests due to hangs

models/demos/t3000/falcon40b/tests/test_perplexity_falcon.py

@@ -263,7 +263,7 @@ def test_perplexity_huggingface(
         ("prefill", 1, 2048, "BFLOAT8_B-DRAM", 64, 6.55, 0.56, 0.80),
         ("decode", 32, 128, "BFLOAT8_B-SHARDED", 64, 13.91, 0.46, 0.71),
         ("decode", 32, 1024, "BFLOAT8_B-SHARDED", 64, 7.79, 0.54, 0.78),
-        ("decode", 32, 2048, "BFLOAT8_B-SHARDED", 64, 6.96, 0.55, 0.79),
+        ("decode", 32, 2048, "BFLOAT8_B-SHARDED", 64, 6.96, 0.55, 0.79),  # TODO: Hangs on CI
     ),
     ids=[
         "prefill_seq128",
@@ -290,6 +290,9 @@ def test_perplexity(
 ):
     assert is_wormhole_b0(), "This test is only for Wormhole B0"
 
+    if llm_mode == "decode" and max_seq_len > 128:
+        pytest.skip("Decode mode is hanging for seqlen > 128")
+
     run_test_perplexity(
         llm_mode,
         batch_size,