From 1edf83b3c518a37b7823800824fef79bc6aebb21 Mon Sep 17 00:00:00 2001
From: Luke Usher <luke.usher@outlook.com>
Date: Sat, 11 Jan 2025 03:15:50 +0000
Subject: [PATCH] Apply suggestions from code review

Co-authored-by: Darren Thompson <me@dtho.mp>
---
 ares/n64/aleck64/aleck64.hpp |  2 ++
 ares/n64/aleck64/io.cpp      | 19 ++++++++++++++++---
 ares/n64/memory/bus.hpp      | 12 +++++++++---
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/ares/n64/aleck64/aleck64.hpp b/ares/n64/aleck64/aleck64.hpp
index f632c8d1f..55ed29bfc 100644
--- a/ares/n64/aleck64/aleck64.hpp
+++ b/ares/n64/aleck64/aleck64.hpp
@@ -8,6 +8,7 @@ struct Aleck64 : Memory::RCP<Aleck64> {
 
     template<u32 Size>
     auto writeBurst(u32 address, u32 *value, const char *peripheral) -> void {
+      address = address & 0x00ff'ffff;
       if (address >= size) return;
       Memory::Writable::write<Word>(address | 0x00, value[0]);
       Memory::Writable::write<Word>(address | 0x04, value[1]);
@@ -23,6 +24,7 @@ struct Aleck64 : Memory::RCP<Aleck64> {
 
     template<u32 Size>
     auto readBurst(u32 address, u32 *value, const char *peripheral) -> void {
+      address = address & 0x00ff'ffff
       if (address >= size) {
         value[0] = value[1] = value[2] = value[3] = 0;
         if (Size == ICache)
diff --git a/ares/n64/aleck64/io.cpp b/ares/n64/aleck64/io.cpp
index 6c4f66eb4..40708d617 100644
--- a/ares/n64/aleck64/io.cpp
+++ b/ares/n64/aleck64/io.cpp
@@ -1,6 +1,6 @@
 auto Aleck64::readWord(u32 address, Thread& thread) -> u32 {
   if(address <= 0xc07f'ffff) {
-    return sdram.read<Word>(address);
+    return sdram.read<Word>(address & 0x00ff'ffff);
   }
 
   controls.poll();
@@ -9,6 +9,7 @@ auto Aleck64::readWord(u32 address, Thread& thread) -> u32 {
       case 0xc080'0000: return readPort1();
       case 0xc080'0004: return readPort2();
       case 0xc080'0008: return readPort3();
+      case 0xc080'0100: return readPort4(); // can just be a stub for now, game is happy without it
     }
   }
 
@@ -18,12 +19,13 @@ auto Aleck64::readWord(u32 address, Thread& thread) -> u32 {
 
 auto Aleck64::writeWord(u32 address, u32 data, Thread& thread) -> void {
   if(address <= 0xc07f'ffff) {
-    return sdram.write<Word>(address, data);
+    return sdram.write<Word>(address & 0x00ff'ffff, data);
   }
 
   if(address <= 0xc080'0fff) {
     switch (address & 0xffff'fffc) {
       case 0xc080'0008: return writePort3(data);
+      case 0xc080'0100: return writePort4(data);
     }
   }
 
@@ -56,4 +58,15 @@ auto Aleck64::writePort3(n32 data) -> void {
   if(gameConfig) return gameConfig->writeExpansionPort(data);
   //debug(unusual, "[Aleck64::writePort3] ", hex(data, 8L));
   print("[Aleck64::writePort3] ", hex(data, 8L), "\n");
-}
\ No newline at end of file
+}
+
+auto Aleck64::readPort4() -> u32 {
+  //debug(unimplemented, "[Aleck64::readPort4]");
+  print("[Aleck64::readPort4]\n");
+  return 0x0;
+}
+
+auto Aleck64::writePort4(n32 data) -> void {
+  // debug(unimplemented, "[Aleck64::writePort3] ", hex(data, 8L));
+  print("[Aleck64::writePort4] ", hex(data, 8L), "\n");
+}
diff --git a/ares/n64/memory/bus.hpp b/ares/n64/memory/bus.hpp
index d09fdf263..7d44126ac 100644
--- a/ares/n64/memory/bus.hpp
+++ b/ares/n64/memory/bus.hpp
@@ -20,7 +20,10 @@ inline auto Bus::read(u32 address, Thread& thread, const char *peripheral) -> u6
   if(address <= 0x1fbf'ffff) return pi.read<Size>(address, thread);
   if(address <= 0x1fcf'ffff) return si.read<Size>(address, thread);
   if(address <= 0x7fff'ffff) return pi.read<Size>(address, thread);
-  if(Model::Aleck64())       return aleck64.read<Size>(address, thread);
+  if(Model::Aleck64()) {
+    if(address <= 0xbfff'ffff) return freezeUnmapped(address), 0;
+    if(address <= 0xc0800'fff) return aleck64.read<Size>(address, thread);
+  }
   return freezeUnmapped(address), 0;
 }
 
@@ -46,7 +49,7 @@ inline auto Bus::readBurst(u32 address, u32 *data, Thread& thread) -> void {
 
   if(Model::Aleck64()) {
     if(address <= 0xbfff'ffff) return freezeUncached(address);
-    if(address <= 0xc07f'ffff) return aleck64.sdram.writeBurst<Size>(address, data, "CPU");
+    if(address <= 0xc07f'ffff) return aleck64.sdram.readBurst<Size>(address, data, "CPU");
   }
 
   return freezeUncached(address);
@@ -77,7 +80,10 @@ inline auto Bus::write(u32 address, u64 data, Thread& thread, const char *periph
   if(address <= 0x1fbf'ffff) return pi.write<Size>(address, data, thread);
   if(address <= 0x1fcf'ffff) return si.write<Size>(address, data, thread);
   if(address <= 0x7fff'ffff) return pi.write<Size>(address, data, thread);
-  if(Model::Aleck64())       return aleck64.write<Size>(address, data, thread);
+  if(Model::Aleck64()) {
+    if(address <= 0xbfff'ffff) return freezeUnmapped(address);
+    if(address <= 0xc0800'fff) return aleck64.write<Size>(address, data, thread);
+  }
   return freezeUnmapped(address);
 }