From 6620a91a224b7a9fbc4cf4089c80be39763eb9b8 Mon Sep 17 00:00:00 2001
From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Tue, 14 Aug 2018 15:30:24 +0200
Subject: [PATCH] core/refresher: synchronize valid

---
 litedram/core/multiplexer.py | 2 +-
 litedram/core/refresher.py   | 9 +++++----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/litedram/core/multiplexer.py b/litedram/core/multiplexer.py
index b019304..70c3738 100644
--- a/litedram/core/multiplexer.py
+++ b/litedram/core/multiplexer.py
@@ -325,7 +325,7 @@ class Multiplexer(Module, AutoCSR):
         fsm.act("REFRESH",
             steerer.sel[0].eq(STEER_REFRESH),
             refresher.cmd.ready.eq(1),
-            If(refresher.cmd.last,
+            If(~refresher.cmd.valid,
                 NextState("READ")
             )
         )
diff --git a/litedram/core/refresher.py b/litedram/core/refresher.py
index 904d671..be58b2c 100644
--- a/litedram/core/refresher.py
+++ b/litedram/core/refresher.py
@@ -45,14 +45,16 @@ class Refresher(Module):
         self.comb += self.timer.wait.eq(settings.with_refresh & ~self.timer.done)
 
         # Control FSM
+        cmd_valid = Signal()
         self.submodules.fsm = fsm = FSM()
         fsm.act("IDLE",
             If(self.timer.done,
+                cmd_valid.eq(1),
                 NextState("WAIT_GRANT")
             )
         )
         fsm.act("WAIT_GRANT",
-            cmd.valid.eq(1),
+            cmd_valid.eq(1),
             If(cmd.ready,
                 seq_start.eq(1),
                 NextState("WAIT_SEQ")
@@ -60,9 +62,8 @@ class Refresher(Module):
         )
         fsm.act("WAIT_SEQ",
             If(seq_done,
-                cmd.last.eq(1),
+                cmd_valid.eq(0),
                 NextState("IDLE")
-            ).Else(
-                cmd.valid.eq(1)
             )
         )
+        self.sync += cmd.valid.eq(cmd_valid)