pytholite/io: support memory

This commit is contained in:
Sebastien Bourdeauducq 2012-11-23 20:36:09 +01:00
parent f42683b71e
commit 95122bb778
2 changed files with 30 additions and 2 deletions

View File

@ -10,6 +10,11 @@ from migen.pytholite.fsm import *
from migen.pytholite.expr import ExprCompiler
class Pytholite(UnifiedIOObject):
def __init__(self, dataflow=None, buses={}):
super().__init__(dataflow, buses)
self.memory_ports = dict((mem, mem.get_port(write_capable=True, we_granularity=8))
for mem in self._memories)
def get_fragment(self):
return super().get_fragment() + self.fragment
@ -107,7 +112,6 @@ def _gen_wishbone_io(compiler, modelname, model, to_model, from_model, bus):
else:
state.append(bus.sel.eq(compiler.ec.visit_expr(sel)))
else:
state.append(bus.we.eq(0))
ec = _BusReadExprCompiler(compiler.symdict, modelname, bus.dat_r)
for target_regs, expr in from_model:
cexpr = ec.visit_expr(expr)
@ -115,6 +119,28 @@ def _gen_wishbone_io(compiler, modelname, model, to_model, from_model, bus):
state.append(If(~bus.ack, AbstractNextState(state)))
return [state], [state]
def _gen_memory_io(compiler, modelname, model, to_model, from_model, port):
s1 = [port.adr.eq(compiler.ec.visit_expr(to_model["address"]))]
if model == TWrite:
if from_model:
raise TypeError("Attempted to read from write transaction")
s1.append(port.dat_w.eq(compiler.ec.visit_expr(to_model["data"])))
sel = to_model["sel"]
if isinstance(sel, ast.Name) and sel.id == "None":
nbytes = (len(port.dat_w) + 7)//8
s1.append(port.we.eq(2**nbytes-1))
else:
s1.append(port.we.eq(compiler.ec.visit_expr(sel)))
return [s1], [s1]
else:
s2 = []
s1.append(AbstractNextState(s2))
ec = _BusReadExprCompiler(compiler.symdict, modelname, port.dat_r)
for target_regs, expr in from_model:
cexpr = ec.visit_expr(expr)
s2 += [reg.load(cexpr) for reg in target_regs]
return [s1, s2], [s2]
def _gen_bus_io(compiler, modelname, model, to_model, from_model):
busname = ast.literal_eval(to_model["busname"])
if busname is None:
@ -125,6 +151,9 @@ def _gen_bus_io(compiler, modelname, model, to_model, from_model):
bus = compiler.ioo.buses[busname]
if isinstance(bus, wishbone.Interface):
return _gen_wishbone_io(compiler, modelname, model, to_model, from_model, bus)
elif isinstance(bus, Memory):
port = compiler.ioo.memory_ports[bus]
return _gen_memory_io(compiler, modelname, model, to_model, from_model, port)
else:
raise NotImplementedError("Unsupported bus")

View File

@ -10,7 +10,6 @@ class UnifiedIOObject(Actor):
if dataflow is not None:
super().__init__(*dataflow)
self.buses = buses
self._memories = set(v for v in self.buses.values() if isinstance(v, Memory))
def get_fragment(self):