Memory: Correct Normal Memory Protections and only use accelerated read on fastmem.

src/core/memory.cpp

@@ -322,7 +322,7 @@ struct Memory::Impl {
         }
 
         if (Settings::IsFastmemEnabled()) {
-            const bool is_read_enable = Settings::IsGPULevelHigh() || !cached;
+            const bool is_read_enable = !Settings::IsGPULevelExtreme() || !cached;
             system.DeviceMemory().buffer.Protect(vaddr, size, is_read_enable, !cached);
         }
 

src/video_core/engines/maxwell_3d.cpp

@@ -30,6 +30,7 @@ Maxwell3D::Maxwell3D(Core::System& system_, MemoryManager& memory_manager_)
       upload_state{memory_manager, regs.upload} {
     dirty.flags.flip();
     InitializeRegisterDefaults();
+    accelerated_reads = Settings::IsFastmemEnabled();
 }
 
 Maxwell3D::~Maxwell3D() = default;
@@ -696,7 +697,7 @@ void Maxwell3D::RecalculateVertexArrayLimit() {
 
     auto maybe_ptr = memory_manager.GpuToHostPointer(start_address + offset);
     u8* ptr;
-    if (maybe_ptr) {
+    if (accelerated_reads && maybe_ptr) {
         ptr = *maybe_ptr;
     } else {
         vn_state.index_buffer_cache.resize(Common::DivideUp(expected_size, sizeof(u32)));

src/video_core/engines/maxwell_3d.h

@@ -1506,6 +1506,8 @@ public:
         std::vector<u32> index_buffer_cache;
     } vertex_num_approx_state;
 
+    bool accelerated_reads{};
+
 private:
     void InitializeRegisterDefaults();