corelogic: convert timeline to function and move to misc

migen/bus/wishbone2csr.py

@@ -1,16 +1,12 @@
 from migen.bus import wishbone
 from migen.bus import csr
 from migen.fhdl.structure import *
-from migen.corelogic import timeline
+from migen.corelogic.misc import timeline
 
 class WB2CSR:
 	def __init__(self):
 		self.wishbone = wishbone.Interface()
 		self.csr = csr.Interface()
-		self.timeline = timeline.Timeline(self.wishbone.cyc & self.wishbone.stb,
-			[(1, [self.csr.we.eq(self.wishbone.we)]),
-			(2, [self.wishbone.ack.eq(1)]),
-			(3, [self.wishbone.ack.eq(0)])])
 	
 	def get_fragment(self):
 		sync = [
@@ -19,4 +15,9 @@ class WB2CSR:
 			self.csr.adr.eq(self.wishbone.adr[:14]),
 			self.wishbone.dat_r.eq(self.csr.dat_r)
 		]
-		return Fragment(sync=sync) + self.timeline.get_fragment()
+		sync += timeline(self.wishbone.cyc & self.wishbone.stb, [
+			(1, [self.csr.we.eq(self.wishbone.we)]),
+			(2, [self.wishbone.ack.eq(1)]),
+			(3, [self.wishbone.ack.eq(0)])
+		])
+		return Fragment(sync=sync)

migen/corelogic/misc.py

@@ -64,3 +64,30 @@ def chooser(signal, shift, output, n=None, reverse=False):
 		cases.append([Constant(i, shift.bv), output.eq(signal[s*w:(s+1)*w])])
 	cases[n-1][0] = Default()
 	return Case(shift, *cases)
+
+def timeline(trigger, events):
+	lastevent = max([e[0] for e in events])
+	counter = Signal(BV(bits_for(lastevent)))
+	
+	counterlogic = If(counter != Constant(0, counter.bv),
+		counter.eq(counter + Constant(1, counter.bv))
+	).Elif(trigger,
+		counter.eq(Constant(1, counter.bv))
+	)
+	# insert counter reset if it doesn't naturally overflow
+	# (test if lastevent+1 is a power of 2)
+	if (lastevent & (lastevent + 1)) != 0:
+		counterlogic = If(counter == lastevent,
+			counter.eq(Constant(0, counter.bv))
+		).Else(
+			counterlogic
+		)
+	
+	def get_cond(e):
+		if e[0] == 0:
+			return trigger & (counter == Constant(0, counter.bv))
+		else:
+			return counter == Constant(e[0], counter.bv)
+	sync = [If(get_cond(e), *e[1]) for e in events]
+	sync.append(counterlogic)
+	return sync

migen/corelogic/timeline.py

@@ -1,32 +0,0 @@
-from migen.fhdl.structure import *
-
-class Timeline:
-	def __init__(self, trigger, events):
-		self.trigger = trigger
-		self.events = events
-		self.lastevent = max([e[0] for e in events])
-	
-	def get_fragment(self):
-		counter = Signal(BV(bits_for(self.lastevent)))
-		
-		counterlogic = If(counter != Constant(0, counter.bv),
-			counter.eq(counter + Constant(1, counter.bv))
-		).Elif(self.trigger,
-			counter.eq(Constant(1, counter.bv))
-		)
-		# insert counter reset if it doesn't automatically overflow
-		# (test if self.lastevent+1 is a power of 2)
-		if (self.lastevent & (self.lastevent + 1)) != 0:
-			counterlogic = If(counter == self.lastevent,
-				counter.eq(Constant(0, counter.bv))
-			).Else(
-				counterlogic
-			)
-		def get_cond(e):
-			if e[0] == 0:
-				return self.trigger & (counter == Constant(0, counter.bv))
-			else:
-				return counter == Constant(e[0], counter.bv)
-		sync = [If(get_cond(e), *e[1]) for e in self.events]
-		sync.append(counterlogic)
-		return Fragment(sync=sync)