Files
PeakRDL-regblock/peakrdl/regblock/scan_design.py
2021-12-15 22:03:57 -08:00

102 lines
3.9 KiB
Python

from typing import TYPE_CHECKING
from collections import OrderedDict
from systemrdl.walker import RDLListener, RDLWalker
from systemrdl.node import AddrmapNode, SignalNode
if TYPE_CHECKING:
from systemrdl.node import Node, RegNode, MemNode, FieldNode
from .exporter import RegblockExporter
class DesignScanner(RDLListener):
"""
Scans through the register model and validates that any unsupported features
are not present.
Also collects any information that is required prior to the start of the export process.
"""
def __init__(self, exp:'RegblockExporter'):
self.exp = exp
self.cpuif_data_width = 0
self.msg = exp.top_node.env.msg
# Collections of signals that were actually referenced by the design
self.in_hier_signal_paths = set()
self.out_of_hier_signals = OrderedDict()
def _get_out_of_hier_field_reset(self):
current_node = self.exp.top_node.parent
while current_node is not None:
for signal in current_node.signals():
if signal.get_property('field_reset'):
path = signal.get_path()
self.out_of_hier_signals[path] = signal
return
current_node = current_node.parent
def do_scan(self):
# Collect cpuif reset, if any.
cpuif_reset = self.exp.top_node.cpuif_reset
if cpuif_reset is not None:
path = cpuif_reset.get_path()
rel_path = cpuif_reset.get_rel_path(self.exp.top_node)
if rel_path.startswith("^"):
self.out_of_hier_signals[path] = cpuif_reset
else:
self.in_hier_signal_paths.add(path)
# collect out-of-hier field_reset, if any
self._get_out_of_hier_field_reset()
RDLWalker().walk(self.exp.top_node, self)
if self.msg.had_error:
self.msg.fatal(
"Unable to export due to previous errors"
)
raise ValueError
def enter_Reg(self, node: 'RegNode') -> None:
# The CPUIF's bus width is sized according to the largest register in the design
self.cpuif_data_width = max(self.cpuif_data_width, node.get_property('regwidth'))
def enter_Component(self, node: 'Node') -> None:
if not isinstance(node, AddrmapNode) and node.external:
self.msg.error(
"Exporter does not support external components",
node.inst.inst_src_ref
)
def enter_Signal(self, node: 'SignalNode') -> None:
# If encountering a CPUIF reset that is nested within the register model,
# warn that it will be ignored.
# Only cpuif resets in the top-level node or above will be honored
if node.get_property('cpuif_reset') and (node.parent != self.exp.top_node):
self.msg.warning(
"Only cpuif_reset signals that are instantiated in the top-level "
+ "addrmap or above will be honored. Any cpuif_reset signals nested "
+ "within children of the addrmap being exported will be ignored.",
node.inst.inst_src_ref
)
if node.get_property('field_reset'):
path = node.get_path()
self.in_hier_signal_paths.add(path)
def enter_Field(self, node: 'FieldNode') -> None:
for prop_name in node.list_properties():
value = node.get_property(prop_name)
if isinstance(value, SignalNode):
path = value.get_path()
rel_path = value.get_rel_path(self.exp.top_node)
if rel_path.startswith("^"):
self.out_of_hier_signals[path] = value
else:
self.in_hier_signal_paths.add(path)
def enter_Mem(self, node: 'MemNode') -> None:
self.msg.error(
"Cannot export a register block that contains a memory",
node.inst.inst_src_ref
)