From 8eeec0bae8af9ce5cb7b5822af5f3e24707362d8 Mon Sep 17 00:00:00 2001
From: morgan <mc@m-labs.hk>
Date: Wed, 27 Mar 2024 12:44:03 +0800
Subject: [PATCH] fix freq counter need long delay to work

---
 src/gateware/wrpll.py | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/gateware/wrpll.py b/src/gateware/wrpll.py
index 268bda1..404d41c 100644
--- a/src/gateware/wrpll.py
+++ b/src/gateware/wrpll.py
@@ -14,9 +14,17 @@ class FrequencyCounter(Module, AutoCSR):
             setattr(self, name, counter)
         self.update_en = CSRStorage()
 
+        # # #
+
         timer = Signal(counter_width)
         timer_tick = Signal()
-        self.sync += Cat(timer, timer_tick).eq(timer + 1)
+        self.sync +=[
+            If(self.update_en.storage, 
+                Cat(timer, timer_tick).eq(timer + 1)
+            ).Else(
+                Cat(timer, timer_tick).eq(0)
+            )
+        ]
 
         for domain in domains:
             sync_domain = getattr(self.sync, domain)
@@ -30,18 +38,17 @@ class FrequencyCounter(Module, AutoCSR):
 
             divided_sys_r = Signal()
             divided_tick = Signal()
-            self.sync += divided_sys_r.eq(divided_sys)
-            self.comb += divided_tick.eq(divided_sys & ~divided_sys_r)
+            self.sync += [
+                divided_sys_r.eq(divided_sys),
+                divided_tick.eq(divided_sys & ~divided_sys_r)
+            ]
 
             counter = Signal(counter_width)
             counter_csr = getattr(self, "counter_" + domain)
             self.sync += [
-                If(timer_tick,
-                    If(self.update_en.storage, counter_csr.status.eq(counter)),
-                    counter.eq(0),
-                ).Else(
-                    If(divided_tick, counter.eq(counter + 1))
-                )
+                If(timer_tick, counter_csr.status.eq(counter)),
+                If(divided_tick, counter.eq(counter + 1)),
+                If(~self.update_en.storage, counter.eq(0)),
             ]
 
 class SkewTester(Module, AutoCSR):