flow: actor busy signal

diff --git a/migen/flow/actor.py b/migen/flow/actor.py
index 344243147a054fcabfc7021bc0b9b849cd127916..a1f57e4fae0a46b8d147b6bd8daa65ded71b883c 100644 (file)
--- a/migen/flow/actor.py
+++ b/migen/flow/actor.py
@@ -1,4 +1,5 @@
 from migen.fhdl.structure import *
+from migen.corelogic.misc import optree
 
 class SchedulingModel:
        COMBINATORIAL, SEQUENTIAL, PIPELINE, DYNAMIC = range(4)
@@ -49,10 +50,10 @@ class Source(Endpoint):
        def __repr__(self):
                return "<Source " + str(self.token) + ">"
 
-def _control_fragment_comb(stb_i, ack_o, stb_o, ack_i):
-       return Fragment([stb_o.eq(stb_i), ack_o.eq(ack_i)])
+def _control_fragment_comb(stb_i, ack_o, stb_o, ack_i, busy):
+       return Fragment([stb_o.eq(stb_i), ack_o.eq(ack_i), busy.eq(0)])
 
-def _control_fragment_seq(latency, stb_i, ack_o, stb_o, ack_i, trigger):
+def _control_fragment_seq(latency, stb_i, ack_o, stb_o, ack_i, busy, trigger):
        ready = Signal()
        timer = Signal(BV(bits_for(latency)))
        comb = [ready.eq(timer == 0)]
@@ -69,6 +70,7 @@ def _control_fragment_seq(latency, stb_i, ack_o, stb_o, ack_i, trigger):
                stb_o.eq(ready & mask),
                trigger.eq(stb_i & (ack_i | ~mask) & ready),
                ack_o.eq(trigger),
+               busy.eq(~ready)
        ]
        sync += [
                If(trigger, mask.eq(1)),
@@ -77,7 +79,7 @@ def _control_fragment_seq(latency, stb_i, ack_o, stb_o, ack_i, trigger):
 
        return Fragment(comb, sync)
 
-def _control_fragment_pipe(latency, stb_i, ack_o, stb_o, ack_i, pipe_ce):
+def _control_fragment_pipe(latency, stb_i, ack_o, stb_o, ack_i, busy, pipe_ce):
        valid = Signal(BV(latency))
        if latency > 1:
                sync = [If(pipe_ce, valid.eq(Cat(stb_i, valid[:latency-1])))]
@@ -88,7 +90,8 @@ def _control_fragment_pipe(latency, stb_i, ack_o, stb_o, ack_i, pipe_ce):
        comb = [
                pipe_ce.eq(ack_i | ~last_valid),
                ack_o.eq(pipe_ce),
-               stb_o.eq(last_valid)
+               stb_o.eq(last_valid),
+               busy.eq(optree('|', [valid[i] for i in range(latency)]))
        ]
        
        return Fragment(comb, sync)
@@ -107,6 +110,7 @@ class Actor:
                                self.endpoints.append(Source(sources))
                else:
                        self.endpoints = endpoints
+               self.busy = Signal()
                if self.scheduling_model.model == SchedulingModel.SEQUENTIAL:
                        self.trigger = Signal()
                elif self.scheduling_model.model == SchedulingModel.PIPELINE:
@@ -136,11 +140,11 @@ class Actor:
                stb_o = source.stb
                ack_i = source.ack
                if self.scheduling_model.model == SchedulingModel.COMBINATORIAL:
-                       return _control_fragment_comb(stb_i, ack_o, stb_o, ack_i)
+                       return _control_fragment_comb(stb_i, ack_o, stb_o, ack_i, self.busy)
                elif self.scheduling_model.model == SchedulingModel.SEQUENTIAL:
-                       return _control_fragment_seq(self.scheduling_model.latency, stb_i, ack_o, stb_o, ack_i, self.trigger)
+                       return _control_fragment_seq(self.scheduling_model.latency, stb_i, ack_o, stb_o, ack_i, self.busy, self.trigger)
                elif self.scheduling_model.model == SchedulingModel.PIPELINE:
-                       return _control_fragment_pipe(self.scheduling_model.latency, stb_i, ack_o, stb_o, ack_i, self.pipe_ce)
+                       return _control_fragment_pipe(self.scheduling_model.latency, stb_i, ack_o, stb_o, ack_i, self.busy, self.pipe_ce)
                elif self.scheduling_model.model == SchedulingModel.DYNAMIC:
                        raise NotImplementedError("Actor classes with dynamic scheduling must overload get_control_fragment")
        

diff --git a/migen/flow/network.py b/migen/flow/network.py
index e46cd4d4422f47776192fcd89b672aa316231e62..409e32c2699d4d12e95deb21eb34ce26d53c5b68 100644 (file)
--- a/migen/flow/network.py
+++ b/migen/flow/network.py
@@ -1,6 +1,8 @@
 import networkx as nx
 
+from migen.fhdl.structure import *
 from migen.flow.actor import *
+from migen.corelogic.misc import optree
 
 class CompositeActor(Actor):
        def __init__(self, dfg):
@@ -22,7 +24,8 @@ class CompositeActor(Actor):
                this = sum([get_conn_control_fragment(x[2]['source'], x[2]['sink'])
                        for x in self.dfg.edges(data=True)], Fragment())
                others = sum([node.get_control_fragment() for node in self.dfg], Fragment())
-               return this + others
+               busy = Fragment([self.busy.eq(optree('|', [node.busy for node in self.dfg]))])
+               return this + others + busy
        
        def get_process_fragment(self):
                this = sum([get_conn_process_fragment(x[2]['source'], x[2]['sink'])