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+# Copyright (C) 2020 Arm Limited or its affiliates. All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the License); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an AS IS BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+# Description:
+# Serialises and packs an NPU subgraph into tensors.
+
+from .nn_graph import PassPlacement
+from .tensor import MemArea, Tensor, TensorPurpose, TensorFormat
+from .operation import Operation
+from .data_type import DataType
+import numpy as np
+from . import driver_actions
+import struct
+
+
+def make_memory_tensor(name, mem_area, sz, want_values, arch):
+ tens = Tensor([sz], DataType.uint8, name)
+ tens.mem_area = mem_area
+ tens.purpose = TensorPurpose.FeatureMap
+ tens.set_format(TensorFormat.NHWC, arch)
+ if want_values:
+ tens.values = np.zeros(tens.shape, np.uint8)
+ return tens
+
+
+def copy_compressed_values_to_memory_tensor(memory_tensor, src_tensor):
+ start_addr = src_tensor.address
+ for compressed_values in src_tensor.compressed_values:
+ end_addr = start_addr + len(compressed_values)
+ memory_tensor.values[start_addr:end_addr] = compressed_values
+ start_addr = end_addr
+
+
+def serialise_npu_subgraph_into_tensors(nng, sg, arch, scratch_tens, flash_tens):
+ if sg.placement != PassPlacement.Npu:
+ return scratch_tens, flash_tens
+
+ flash_area = arch.permanent_storage_mem_area
+ scratch_area = MemArea.Sram
+
+ flash_size = sg.memory_used.get(flash_area, 0)
+ scratch_size = sg.memory_used.get(scratch_area, 0)
+
+ # Prepare driver actions for this command tensor
+ da_list = []
+ driver_actions.emit_fourcc(da_list, "COP1")
+ driver_actions.emit_config(da_list, 0, 1, arch)
+ driver_actions.emit_cmd_stream_header(da_list, len(sg.register_command_stream))
+
+ # Append command stream words
+ da_list.extend(sg.register_command_stream)
+
+ # Convert to bytes
+ payload_bytes = struct.pack("<{0}I".format(len(da_list)), *da_list)
+
+ command_stream_size_bytes = len(payload_bytes)
+
+ # Adjust the bits per element calculation to exclude metadata generated by Vela
+ nng.total_size[flash_area] = nng.total_size.get(flash_area, 0) - flash_size - command_stream_size_bytes
+ nng.total_elements[flash_area] = nng.total_elements.get(flash_area, 0) - flash_size - command_stream_size_bytes
+ nng.total_size[scratch_area] = nng.total_size.get(scratch_area, 0) - scratch_size
+ nng.total_elements[scratch_area] = nng.total_elements.get(scratch_area, 0) - scratch_size
+
+ if flash_tens == scratch_tens == None:
+ # First Npu subgraph, create scratch and flash tensors
+ sg.scratch_tensor = make_memory_tensor(sg.name + "_scratch", scratch_area, scratch_size, False, arch)
+ sg.scratch_tensor.purpose = TensorPurpose.Scratch
+ sg.flash_tensor = make_memory_tensor(sg.name + "_flash", flash_area, flash_size, True, arch)
+ else:
+ sg.scratch_tensor = scratch_tens
+ sg.scratch_tensor.shape[0] += scratch_size
+ sg.flash_tensor = flash_tens
+ sg.flash_tensor.shape[0] += flash_size
+
+ for cps in sg.cascaded_passes:
+ for ps in cps.passes:
+ if ps.placement == PassPlacement.Npu and ps.weight_tensor != None:
+ # For DMA ops, ps.weight_tensor is referring to the SRAM weight tensor and therefore the address
+ # is pointing at the destination address of where the weights should be placed in SRAM.
+ # This ensures that the Flash weight tensor is used instead and thus gets the correct address.
+ if ps.weight_tensor.ops[0].type == "DMA":
+ copy_compressed_values_to_memory_tensor(sg.flash_tensor, ps.weight_tensor.ops[0].inputs[0])
+ else:
+ copy_compressed_values_to_memory_tensor(sg.flash_tensor, ps.weight_tensor)
+
+ copy_compressed_values_to_memory_tensor(sg.flash_tensor, ps.scale_tensor)
+
+ sg.command_stream_tensor = make_memory_tensor(
+ sg.name + "_command_stream", flash_area, command_stream_size_bytes, True, arch
+ )
+ sg.command_stream_tensor.values = np.frombuffer(payload_bytes, dtype=np.uint8)
+
+ return sg.scratch_tensor, sg.flash_tensor
+
+
+def add_const_tens_to_startup_cascaded_pass(startup_cps, tens):
+ op = Operation("Const", tens.name + "_const")
+ op.outputs = [tens]
+ tens.ops = [op]
+ startup_cps.passes[0].ops.insert(0, op)
+ startup_cps.passes[0].outputs.insert(0, tens)
+ startup_cps.outputs.insert(0, tens)
+
+
+def rewrite_npu_call_ops(nng, sg, arch):
+ if sg.placement != PassPlacement.Cpu:
+ return
+
+ startup_cps = sg.cascaded_passes[0]
+
+ for idx, cps in enumerate(sg.cascaded_passes):
+ for ps in cps.passes:
+ for op in ps.ops:
+ if op.type == "NpuOp":
+ callee = op.attrs["subgraph"]
+ op.attrs["custom_options"] = {"type": op.type}
+
+ sz = 0
+ for tens in [callee.scratch_tensor, callee.flash_tensor, callee.command_stream_tensor]:
+ op.inputs.insert(0, tens)
+ ps.inputs.insert(0, tens)
+ cps.inputs.insert(0, tens)
+ if tens != callee.scratch_tensor:
+ add_const_tens_to_startup_cascaded_pass(startup_cps, tens)
+ sz += tens.storage_size()
+
+ for prev_cps in sg.cascaded_passes[: idx + 1]:
+ prev_cps.sram_used += sz
+
+ if callee.scratch_tensor is not None:
+ cps.sram_used += callee.scratch_tensor.storage_size()