link: test HOLD on RX path

lib/sata/link/__init__.py

@@ -1,14 +1,12 @@
 from migen.fhdl.std import *
 from migen.genlib.fsm import FSM, NextState
+from migen.actorlib.fifo import SyncFIFO
 
 from lib.sata.std import *
 from lib.sata.link.crc import SATACRCInserter, SATACRCChecker
 from lib.sata.link.scrambler import SATAScrambler
 from lib.sata.link.cont import SATACONTInserter, SATACONTRemover
 
-#TODO:
-# -Test HOLD on RX path
-
 from_rx = [
 	("idle", 1),
 	("insert", 32),
@@ -152,6 +150,9 @@ class SATALinkLayerRX(Module):
 				sop.eq(0)
 			)
 
+		# small fifo to manage HOLD
+		self.submodules.fifo = SyncFIFO(link_layout(32), 32)
+
 		# graph
 		self.sync += \
 			If(fsm.ongoing("COPY") & (det == 0),
@@ -165,7 +166,8 @@ class SATALinkLayerRX(Module):
 			scrambler.sink.eop.eq(det == primitives["EOF"]),
 			cont.source.ack.eq(1),
 			Record.connect(scrambler.source, crc.sink),
-			Record.connect(crc.source, self.source)
+			Record.connect(crc.source, self.fifo.sink),
+			Record.connect(self.fifo.source, self.source)
 		]
 
 		# FSM
@@ -187,6 +189,8 @@ class SATALinkLayerRX(Module):
 				insert.eq(primitives["HOLDA"])
 			).Elif(det == primitives["EOF"],
 				NextState("WTRM")
+			).Elif(self.fifo.fifo.level > 8,
+				insert.eq(primitives["HOLD"])
 			)
 		)
 		fsm.act("EOF",

lib/sata/test/bfm.py

@@ -143,6 +143,8 @@ class LinkLayer(Module):
 		self.tx_packet = LinkTXPacket()
 		self.rx_packet = LinkRXPacket()
 		self.rx_cont = False
+		self.tx_cont = False
+		self.tx_cont_primitive = 0
 
 		self.transport_callback = None
 
@@ -186,6 +188,14 @@ class LinkLayer(Module):
 			self.rx_packet.ongoing = True
 
 	def send(self, dword):
+		if dword == primitives["CONT"]:
+			self.tx_cont = True
+		elif is_primitive(dword):
+			self.tx_cont = False
+			self.tx_cont_primitive = dword
+		if self.tx_cont:
+			dword = self.tx_cont_primitive
+
 		if self.send_state == "RDY":
 			self.phy.send(primitives["X_RDY"])
 			if dword == primitives["R_RDY"]:
@@ -194,9 +204,12 @@ class LinkLayer(Module):
 			self.phy.send(primitives["SOF"])
 			self.send_state = "DATA"
 		elif self.send_state == "DATA":
-			self.phy.send(self.tx_packet.pop(0))
+			if dword == primitives["HOLD"]:
-			if len(self.tx_packet) == 0:
+				self.phy.send(primitives["HOLDA"])
-				self.send_state = "EOF"
+			else:
+				self.phy.send(self.tx_packet.pop(0))
+				if len(self.tx_packet) == 0:
+					self.send_state = "EOF"
 		elif self.send_state == "EOF":
 			self.phy.send(primitives["EOF"])
 			self.send_state = "WTRM"
@@ -209,6 +222,7 @@ class LinkLayer(Module):
 
 	def gen_simulation(self, selfp):
 		self.tx_packet.done = True
+		self.phy.send(primitives["SYNC"])
 		while True:
 			yield from self.phy.receive()
 			self.phy.send(primitives["SYNC"])

lib/sata/test/link_tb.py

@@ -57,7 +57,6 @@ class LinkLogger(Module):
 		selfp.sink.ack = 1
 		if selfp.sink.stb == 1 and selfp.sink.sop == 1:
 			self.packet = LinkRXPacket()
-			print("rx : %08x" %selfp.sink.d)
 			self.packet.append(selfp.sink.d)
 		elif selfp.sink.stb:
 			self.packet.append(selfp.sink.d)
@@ -66,25 +65,28 @@ class LinkLogger(Module):
 
 class TB(Module):
 	def __init__(self):
-		self.submodules.bfm = BFM(phy_debug=False,
+		self.submodules.bfm = BFM(phy_debug=True,
-				link_random_level=50, transport_debug=False, transport_loopback=True)
+				link_random_level=50, transport_debug=True, transport_loopback=True)
 		self.submodules.link_layer = SATALinkLayer(self.bfm.phy)
 
 		self.submodules.streamer = LinkStreamer()
 		streamer_ack_randomizer = AckRandomizer(link_layout(32), level=50)
 		self.submodules += streamer_ack_randomizer
 		self.submodules.logger = LinkLogger()
+		logger_ack_randomizer = AckRandomizer(link_layout(32), level=80)
+		self.submodules += logger_ack_randomizer
 		self.comb += [
 			Record.connect(self.streamer.source, streamer_ack_randomizer.sink),
 			Record.connect(streamer_ack_randomizer.source, self.link_layer.sink),
-			Record.connect(self.link_layer.source, self.logger.sink)
+			Record.connect(self.link_layer.source, logger_ack_randomizer.sink),
+			Record.connect(logger_ack_randomizer.source, self.logger.sink)
 		]
 
 	def gen_simulation(self, selfp):
 		for i in range(24):
 			yield
 		for i in range(8):
-			yield from self.streamer.send(LinkTXPacket([i for i in range(16)]))
+			yield from self.streamer.send(LinkTXPacket([i for i in range(64)]))
 			yield from self.logger.receive()
 			print("Logger:")
 			print("-------")
@@ -93,4 +95,4 @@ class TB(Module):
 
 
 if __name__ == "__main__":
-	run_simulation(TB(), ncycles=512, vcd_name="my.vcd", keep_files=True)
+	run_simulation(TB(), ncycles=2048, vcd_name="my.vcd", keep_files=True)