Files
PeakRDL-BusDecoder/src/peakrdl_regblock/field_logic/sw_onwrite.py

130 lines
4.3 KiB
Python

from typing import TYPE_CHECKING, List, Optional
from systemrdl.rdltypes import OnWriteType
from .bases import NextStateConditional
if TYPE_CHECKING:
from systemrdl.node import FieldNode
# TODO: implement sw=w1 "write once" fields
class _OnWrite(NextStateConditional):
onwritetype: Optional[OnWriteType] = None
def is_match(self, field: 'FieldNode') -> bool:
return field.is_sw_writable and field.get_property('onwrite') == self.onwritetype
def get_predicate(self, field: 'FieldNode') -> str:
if field.parent.get_property('buffer_writes'):
# Is buffered write. Use alternate strobe
wstrb = self.exp.write_buffering.get_write_strobe(field)
if field.get_property('swwe') or field.get_property('swwel'):
# dereferencer will wrap swwel complement if necessary
qualifier = self.exp.dereferencer.get_field_propref_value(field, 'swwe')
return f"{wstrb} && {qualifier}"
return wstrb
else:
# is regular register
strb = self.exp.dereferencer.get_access_strobe(field)
if field.get_property('swwe') or field.get_property('swwel'):
# dereferencer will wrap swwel complement if necessary
qualifier = self.exp.dereferencer.get_field_propref_value(field, 'swwe')
return f"{strb} && decoded_req_is_wr && {qualifier}"
return f"{strb} && decoded_req_is_wr"
def get_assignments(self, field: 'FieldNode') -> List[str]:
accesswidth = field.parent.get_property("accesswidth")
# Due to 10.6.1-f, it is impossible for a field with an onwrite action to
# be split across subwords.
# Therefore it is ok to get the subword idx from only one of the bit offsets
sidx = field.low // accesswidth
# field does not get split between subwords
R = self.exp.field_logic.get_storage_identifier(field)
D = self.exp.field_logic.get_wr_data(field, sidx)
S = self.exp.field_logic.get_wr_biten(field, sidx)
lines = [
f"next_c = {self.get_onwrite_rhs(R, D, S)};",
"load_next_c = '1;",
]
return lines
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
raise NotImplementedError
#-------------------------------------------------------------------------------
class WriteOneSet(_OnWrite):
comment = "SW write 1 set"
onwritetype = OnWriteType.woset
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} | ({data} & {strb})"
class WriteOneClear(_OnWrite):
comment = "SW write 1 clear"
onwritetype = OnWriteType.woclr
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} & ~({data} & {strb})"
class WriteOneToggle(_OnWrite):
comment = "SW write 1 toggle"
onwritetype = OnWriteType.wot
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} ^ ({data} & {strb})"
class WriteZeroSet(_OnWrite):
comment = "SW write 0 set"
onwritetype = OnWriteType.wzs
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} | (~{data} & {strb})"
class WriteZeroClear(_OnWrite):
comment = "SW write 0 clear"
onwritetype = OnWriteType.wzc
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} & ({data} | ~{strb})"
class WriteZeroToggle(_OnWrite):
comment = "SW write 0 toggle"
onwritetype = OnWriteType.wzt
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"{reg} ^ (~{data} & {strb})"
class WriteClear(_OnWrite):
comment = "SW write clear"
onwritetype = OnWriteType.wclr
def get_assignments(self, field: 'FieldNode') -> List[str]:
return [
"next_c = '0;",
"load_next_c = '1;",
]
class WriteSet(_OnWrite):
comment = "SW write set"
onwritetype = OnWriteType.wset
def get_assignments(self, field: 'FieldNode') -> List[str]:
return [
"next_c = '1;",
"load_next_c = '1;",
]
class Write(_OnWrite):
comment = "SW write"
onwritetype = None
def get_onwrite_rhs(self, reg: str, data: str, strb: str) -> str:
return f"({reg} & ~{strb}) | ({data} & {strb})"