5 files changed, 118 insertions, 1 deletions
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 1ea243283..26e1636ee 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -35,6 +35,8 @@ add_library(core STATIC
     crypto/ctr_encryption_layer.h
     crypto/xts_encryption_layer.cpp
     crypto/xts_encryption_layer.h
+    device_memory.cpp
+    device_memory.h
     file_sys/bis_factory.cpp
     file_sys/bis_factory.h
     file_sys/card_image.cpp
diff --git a/src/core/core.cpp b/src/core/core.cpp
index 87b147f63..4bc71c7a7 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -14,6 +14,7 @@
 #include "core/core_manager.h"
 #include "core/core_timing.h"
 #include "core/cpu_manager.h"
+#include "core/device_memory.h"
 #include "core/file_sys/bis_factory.h"
 #include "core/file_sys/card_image.h"
 #include "core/file_sys/mode.h"
@@ -113,7 +114,7 @@ FileSys::VirtualFile GetGameFileFromPath(const FileSys::VirtualFilesystem& vfs,
 }
 struct System::Impl {
     explicit Impl(System& system)
-        : kernel{system}, fs_controller{system}, memory{system},
+        : kernel{system}, device_memory{system}, fs_controller{system}, memory{system},
           cpu_manager{system}, reporter{system}, applet_manager{system} {}
 
     CoreManager& CurrentCoreManager() {
@@ -337,6 +338,7 @@ struct System::Impl {
 
     Timing::CoreTiming core_timing;
     Kernel::KernelCore kernel;
+    DeviceMemory device_memory;
     /// RealVfsFilesystem instance
     FileSys::VirtualFilesystem virtual_filesystem;
     /// ContentProviderUnion instance
@@ -472,6 +474,14 @@ Kernel::Process* System::CurrentProcess() {
     return impl->kernel.CurrentProcess();
 }
 
+DeviceMemory& System::GetDeviceMemory() {
+    return impl->device_memory;
+}
+
+const DeviceMemory& System::GetDeviceMemory() const {
+    return impl->device_memory;
+}
+
 const Kernel::Process* System::CurrentProcess() const {
     return impl->kernel.CurrentProcess();
 }
diff --git a/src/core/core.h b/src/core/core.h
index c2bdef07e..6cd93000a 100644
--- a/src/core/core.h
+++ b/src/core/core.h
@@ -91,6 +91,7 @@ namespace Core {
 
 class ARM_Interface;
 class CoreManager;
+class DeviceMemory;
 class ExclusiveMonitor;
 class FrameLimiter;
 class PerfStats;
@@ -256,6 +257,12 @@ public:
     /// Gets the global scheduler
     const Kernel::GlobalScheduler& GlobalScheduler() const;
 
+    /// Gets the manager for the guest device memory
+    DeviceMemory& GetDeviceMemory();
+
+    /// Gets the manager for the guest device memory
+    const DeviceMemory& GetDeviceMemory() const;
+
     /// Provides a pointer to the current process
     Kernel::Process* CurrentProcess();
 
diff --git a/src/core/device_memory.cpp b/src/core/device_memory.cpp
new file mode 100644
index 000000000..1e4187546
--- /dev/null
+++ b/src/core/device_memory.cpp
@@ -0,0 +1,50 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+#include "common/assert.h"
+#include "core/core.h"
+#include "core/device_memory.h"
+#include "core/memory.h"
+
+namespace Core {
+
+constexpr u64 DramSize{4ULL * 1024 * 1024 * 1024};
+
+DeviceMemory::DeviceMemory(System& system) : system{system} {
+#ifdef _WIN32
+    base = static_cast<u8*>(
+        VirtualAlloc(nullptr,                                    // System selects address
+                     DramSize,                                   // Size of allocation
+                     MEM_RESERVE | MEM_COMMIT | MEM_WRITE_WATCH, // Allocate reserved pages
+                     PAGE_READWRITE));                           // Protection = no access
+#else
+    physical_memory.resize(DramSize);
+    base = physical_memory.data();
+#endif
+}
+
+DeviceMemory::~DeviceMemory() {
+#ifdef _WIN32
+    ASSERT(VirtualFree(base, DramSize, MEM_RELEASE));
+#endif
+}
+
+PAddr DeviceMemory::GetPhysicalAddr(VAddr addr) {
+    u8* pointer{system.Memory().GetPointer(addr)};
+    ASSERT(pointer);
+    const uintptr_t offset{static_cast<uintptr_t>(pointer - GetPointer(DramMemoryMap::Base))};
+    return DramMemoryMap::Base + offset;
+}
+
+u8* DeviceMemory::GetPointer(PAddr addr) {
+    ASSERT(addr >= DramMemoryMap::Base);
+    ASSERT(addr < DramMemoryMap::Base + DramSize);
+    return base + (addr - DramMemoryMap::Base);
+}
+
+} // namespace Core
diff --git a/src/core/device_memory.h b/src/core/device_memory.h
new file mode 100644
index 000000000..a60a7238a
--- /dev/null
+++ b/src/core/device_memory.h
@@ -0,0 +1,48 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/assert.h"
+#include "common/common_funcs.h"
+#include "core/hle/kernel/physical_memory.h"
+
+namespace Core {
+
+class System;
+
+namespace DramMemoryMap {
+constexpr u64 Base = 0x80000000ULL;
+constexpr u64 Size = 0x100000000ULL;
+constexpr u64 End = Base + Size;
+constexpr u64 KernelReserveBase = Base + 0x60000;
+constexpr u64 SlabHeapBase = KernelReserveBase + 0x85000;
+constexpr u64 SlapHeapSize = 0xa21000;
+constexpr u64 SlabHeapEnd = SlabHeapBase + SlapHeapSize;
+}; // namespace DramMemoryMap
+
+class DeviceMemory : NonCopyable {
+public:
+    DeviceMemory(Core::System& system);
+    ~DeviceMemory();
+
+    template <typename T>
+    PAddr GetPhysicalAddr(T* ptr) {
+        const auto ptr_addr{reinterpret_cast<uintptr_t>(ptr)};
+        const auto base_addr{reinterpret_cast<uintptr_t>(base)};
+        ASSERT(ptr_addr >= base_addr);
+        return ptr_addr - base_addr + DramMemoryMap::Base;
+    }
+
+    PAddr GetPhysicalAddr(VAddr addr);
+
+    u8* GetPointer(PAddr addr);
+
+private:
+    u8* base{};
+    Kernel::PhysicalMemory physical_memory;
+    Core::System& system;
+};
+
+} // namespace Core