From 54dd4e591365e1d9ca718d2772edfb933b976451 Mon Sep 17 00:00:00 2001
From: Jaklyy <102590697+Jaklyy@users.noreply.github.com>
Date: Mon, 21 Oct 2024 13:15:15 -0400
Subject: [PATCH] git hates me

---
 src/CP15.cpp | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/CP15.cpp b/src/CP15.cpp
index 9a87e620..19bc1339 100644
--- a/src/CP15.cpp
+++ b/src/CP15.cpp
@@ -332,9 +332,26 @@ void ARMv5::UpdateRegionTimings(u32 addrstart, u32 addrend)
 
         // checkme: should these be (bus timings shifted) - 1 or ((bustimings - 1) shifted) + 1
         // should the last cycle be halved...?
-        MemTimings[i][0] = ((bustimings[0] - 1) << NDS.ARM9ClockShift) + 1;
-        MemTimings[i][1] = ((bustimings[2] - 1) << NDS.ARM9ClockShift) + 1;
-        MemTimings[i][2] = ((bustimings[3] - 1) << NDS.ARM9ClockShift) + 1;
+        if (NDS.ARM9ClockShift == 1)
+        {
+            MemTimings[i][0] = (bustimings[0] << NDS.ARM9ClockShift) - 1;
+            MemTimings[i][1] = (bustimings[2] << NDS.ARM9ClockShift) - 1;
+            MemTimings[i][2] = (bustimings[3] << NDS.ARM9ClockShift) - 1;
+        }
+        else
+        {
+            if (NDS.ARM9Regions[i] != Mem9_MainRAM)
+            {
+                MemTimings[i][0] = ((bustimings[0] - 1) << NDS.ARM9ClockShift) - 1;
+                MemTimings[i][1] = ((bustimings[2] - 1) << NDS.ARM9ClockShift) - 1;
+            }
+            else
+            {
+                MemTimings[i][0] = (bustimings[0] << NDS.ARM9ClockShift) - 1;
+                MemTimings[i][1] = (bustimings[2] << NDS.ARM9ClockShift) - 1;
+            }
+            MemTimings[i][2] = (bustimings[3] << NDS.ARM9ClockShift) - 1;
+        }
     }
 }