From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Mon, 29 Nov 2021 10:26:35 +0000 (+0000)
Subject: disallow overlap in core on LDST, Branch, and Trap.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a320531e88165ae7f5074d583854c5907b6f4429;p=soc.git

disallow overlap in core on LDST, Branch, and Trap.
these are all the ones that could cause exceptions or mess with ordering
---

diff --git a/src/soc/simple/core.py b/src/soc/simple/core.py
index c6c35b66..f8c3c245 100644
--- a/src/soc/simple/core.py
+++ b/src/soc/simple/core.py
@@ -427,6 +427,14 @@ class NonProductionCore(ControlBase):
             # and resolved
             with m.If(self.issue_conflict):
                 comb += busy_o.eq(1)
+            # make sure that LDST, Branch and Trap all say "busy"
+            # and do not allow overlap
+            for funame, fu in fus.items():
+                if (funame.lower().startswith('ldst') or
+                    funame.lower().startswith('branch') or
+                    funame.lower().startswith('trap')):
+                    with m.If(fu.busy_o):
+                        comb += busy_o.eq(1)
 
         # return both the function unit "enable" dict as well as the "busy".
         # the "busy-or-issued" can be passed in to the Read/Write port