Source code for hwtLib.handshaked.streamNode

from typing import List, Optional, Tuple, Union, Dict

from hwt.code import And, Or
from hwt.hdl.statements.assignmentContainer import HdlAssignmentContainer
from hwt.hdl.types.defs import BIT
from hwt.hdl.value import HValue
from hwt.synthesizer.interface import Interface
from hwt.synthesizer.rtlLevel.constants import NOT_SPECIFIED
from hwt.synthesizer.rtlLevel.rtlSignal import RtlSignal


[docs]def _get_ready_signal(intf: Union[Interface, Tuple[RtlSignal, RtlSignal]]) -> RtlSignal: try: return intf.rd except AttributeError: pass if isinstance(intf, Tuple): _, rd = intf return rd return intf.ready
[docs]def _get_valid_signal(intf: Union[Interface, Tuple[RtlSignal, RtlSignal]]) -> RtlSignal: try: return intf.vld except AttributeError: pass if isinstance(intf, Tuple): vld, _ = intf return vld return intf.valid
[docs]def _exStreamMemberAck(m) -> RtlSignal: c, n = m return c & n.ack()
[docs]class ExclusiveStreamGroups(list): """ list of tuples (cond, StreamNode instance) Only one stream from this group can be activated at the time """
[docs] def __hash__(self): return id(self)
[docs] def sync(self, enSig=None) -> List[HdlAssignmentContainer]: """ Create synchronization logic between streams (generate valid/ready synchronization logic for interfaces) :param enSig: optional signal to enable this group of nodes :return: list of assignments which are responsible for synchronization of streams """ expression = [] for cond, node in self: if enSig is not None: cond = cond & enSig expression.extend(node.sync(cond)) return expression
[docs] def ack(self) -> RtlSignal: """ :return: expression which's value is high when transaction can be made over at least on child streaming node """ return Or(*(_exStreamMemberAck(m) for m in self))
INTERFACE_OR_VLD_RD_TUPLE = Union[Interface, Tuple[Union[RtlSignal, int], Union[RtlSignal, int]]]
[docs]class StreamNode(): """ Group of stream master and slave interfaces to synchronize them to each other :ivar ~.masters: interfaces which are inputs into this node :ivar ~.slaves: interfaces which are outputs of this node :ivar ~.extraConds: {dict interface : extraConditionSignal} where extra conditions will be added to expression for channel enable. For master it means it will obtain ready=1 only if extraConditionSignal is 1. For slave it means it will obtain valid=1 only if extraConditionSignal is 1. All interfaces have to wait on each other so if an extraCond!=1 it causes blocking on all interfaces if not overridden by skipWhen. :note: instead of interface it is possilble to use tuple (valid, ready) signal :ivar ~.skipWhen: dict interface : skipSignal where if skipSignal is high interface is disconnected from stream sync node and others does not have to wait on it (master does not need to have valid and slave ready) :attention: skipWhen has higher priority """
[docs] def __init__(self, masters: Optional[List[INTERFACE_OR_VLD_RD_TUPLE]]=None, slaves: Optional[List[INTERFACE_OR_VLD_RD_TUPLE]]=None, extraConds: Optional[Dict[INTERFACE_OR_VLD_RD_TUPLE, RtlSignal]]=None, skipWhen: Optional[Dict[INTERFACE_OR_VLD_RD_TUPLE, RtlSignal]]=None): if masters is None: masters = [] if slaves is None: slaves = [] if extraConds is None: extraConds = {} if skipWhen is None: skipWhen = {} self.masters = masters self.slaves = slaves self.extraConds = extraConds self.skipWhen = skipWhen
[docs] def sync(self, enSig: Optional[RtlSignal]=None) -> List[HdlAssignmentContainer]: """ Create synchronization logic between streams (generate valid/ready synchronization logic for interfaces) :param enSig: optional signal to enable this node :return: list of assignements which are responsible for synchronization of streams """ masters = self.masters slaves = self.slaves if not masters and not slaves: # node is empty assert not self.extraConds assert not self.skipWhen return [] # check if there is not not any mess in extraConds/skipWhen for i in self.extraConds.keys(): assert i in masters or i in slaves, i for i in self.skipWhen.keys(): assert i in masters or i in slaves, i # this expression container is there to allow usage of this function # in usual hdl containers like If, Switch etc... expression = [] for m in masters: r = self.ackForMaster(m) if enSig is not None: r = r & enSig if isinstance(m, ExclusiveStreamGroups): a = m.sync(r) else: rd = _get_ready_signal(m) if isinstance(rd, int): assert rd == 1 a = [] else: a = [rd(r), ] expression.extend(a) for s in slaves: v = self.ackForSlave(s) if enSig is not None: v = v & enSig if isinstance(s, ExclusiveStreamGroups): a = s.sync(v) else: vld = _get_valid_signal(s) if isinstance(vld, int): assert vld == 1 a = [] else: a = [vld(v), ] expression.extend(a) return expression
[docs] def ack(self) -> RtlSignal: """ :return: expression which's value is high when transaction can be made over interfaces """ # every interface has to have skip flag or it has to be ready/valid # and extraCond has to be True if present acks = [] for m in self.masters: extra, skip = self.getExtraAndSkip(m) if isinstance(m, ExclusiveStreamGroups): a = m.ack() else: a = _get_valid_signal(m) if isinstance(a, (int, HValue)): assert int(a) == 1, (m, a) a = BIT.from_py(1) else: if extra: a = And(a, *extra) if skip is not None: a = Or(a, skip) acks.append(a) for s in self.slaves: extra, skip = self.getExtraAndSkip(s) if isinstance(s, ExclusiveStreamGroups): a = s.ack() else: a = _get_ready_signal(s) if isinstance(a, (int, HValue)): assert int(a) == 1, (s, a) a = BIT.from_py(1) else: if extra: a = And(a, *extra) if skip is not None: a = Or(a, skip) acks.append(a) if not acks: return True return And(*acks)
[docs] def getExtraAndSkip(self, intf: INTERFACE_OR_VLD_RD_TUPLE) -> Tuple[Optional[RtlSignal], Optional[RtlSignal]]: """ :return: optional extraCond and skip flags for interface """ try: extra = [self.extraConds[intf], ] except KeyError: extra = [] try: skip = self.skipWhen[intf] except KeyError: skip = None return extra, skip
[docs] def vld(self, intf: INTERFACE_OR_VLD_RD_TUPLE) -> RtlSignal: """ :return: valid signal of master interface for synchronization of othres """ try: s = self.skipWhen[intf] assert s is not None except KeyError: s = None if isinstance(intf, ExclusiveStreamGroups): v = intf.ack() else: v = _get_valid_signal(intf) if isinstance(v, int): assert v == 1, v return BIT.from_py(1) if s is None: return v else: return v | s
[docs] def rd(self, intf: INTERFACE_OR_VLD_RD_TUPLE) -> RtlSignal: """ :return: ready signal of slave interface for synchronization of othres """ try: s = self.skipWhen[intf] assert s is not None except KeyError: s = None if isinstance(intf, ExclusiveStreamGroups): r = intf.ack() else: r = _get_ready_signal(intf) if isinstance(r, int): assert r == 1, r return BIT.from_py(1) if s is None: return r else: return r | s
[docs] def ackForMaster(self, master: INTERFACE_OR_VLD_RD_TUPLE) -> RtlSignal: """ :return: driver of ready signal for master """ extra, skip = self.getExtraAndSkip(master) rd = self.rd vld = self.vld conds = [*(vld(m) for m in self.masters if m is not master), *(rd(s) for s in self.slaves), *extra] if conds: r = And(*conds) else: r = BIT.from_py(1) if skip is not None: r = r & ~skip return r
[docs] def ackForSlave(self, slave: INTERFACE_OR_VLD_RD_TUPLE) -> RtlSignal: """ :return: driver of valid signal for slave """ extra, skip = self.getExtraAndSkip(slave) rd = self.rd vld = self.vld conds = [*(vld(m) for m in self.masters), *(rd(s) for s in self.slaves if s is not slave), *extra] if conds: v = And(*conds) else: v = BIT.from_py(1) if skip is not None: v = v & ~skip return v
def __repr__format_intf_list(self, intf_list): res = [] for i in intf_list: extraCond = self.extraConds.get(i, NOT_SPECIFIED) skipWhen = self.skipWhen.get(i, NOT_SPECIFIED) if extraCond is not NOT_SPECIFIED and skipWhen is not NOT_SPECIFIED: res.append(f"({i},\n extraCond={extraCond},\n skipWhen={skipWhen})") elif extraCond is not NOT_SPECIFIED: res.append(f"({i},\n extraCond={extraCond})") elif skipWhen is not NOT_SPECIFIED: res.append(f"({i},\n skipWhen={skipWhen})") else: res.append(f"{i}") return ',\n '.join(res)
[docs] def __repr__(self): masters = self.__repr__format_intf_list(self.masters) slaves = self.__repr__format_intf_list(self.slaves) return f"""<{self.__class__.__name__} masters=[ {masters:s}], slaves=[ {slaves:s}], >"""