From a026dd89468e0c995bc69b6d7ef1a40b5718e06a Mon Sep 17 00:00:00 2001
From: Franck Jullien <franck.jullien@gmail.com>
Date: Mon, 20 Sep 2021 10:41:59 +0200
Subject: [PATCH] efinix: add AsyncResetSynchronizer

---
 litex/build/efinix/common.py | 37 +++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/litex/build/efinix/common.py b/litex/build/efinix/common.py
index 9c104ab69..9a4ef0c2b 100644
--- a/litex/build/efinix/common.py
+++ b/litex/build/efinix/common.py
@@ -5,4 +5,39 @@
 # Copyright (c) 2015-2018 Florent Kermarrec <florent@enjoy-digital.fr>
 # SPDX-License-Identifier: BSD-2-Clause
 
-efinix_special_overrides = {}
\ No newline at end of file
+from migen.fhdl.module import Module
+from migen.genlib.resetsync import AsyncResetSynchronizer
+
+from litex.build.io import *
+
+# Efinix AsyncResetSynchronizer ---------------------------------------------------------------------
+
+class EfinixAsyncResetSynchronizerImpl(Module):
+    def __init__(self, cd, async_reset):
+        rst1 = Signal()
+        self.specials += [
+            Instance("EFX_FF",
+                i_D      = 0,
+                i_SR     = async_reset,
+                i_CLK    = cd.clk,
+                i_CE     = 1,
+                o_Q      = rst1),
+            Instance("EFX_FF",
+                i_D      = rst1,
+                i_SR     = async_reset,
+                i_CLK    = cd.clk,
+                i_CE     = 1,
+                o_Q      = cd.rst)
+        ]
+
+
+class EfinixAsyncResetSynchronizer:
+    @staticmethod
+    def lower(dr):
+        return EfinixAsyncResetSynchronizerImpl(dr.cd, dr.async_reset)
+
+# Gowin Special Overrides --------------------------------------------------------------------------
+
+efinix_special_overrides = {
+    AsyncResetSynchronizer: EfinixAsyncResetSynchronizer
+}