Kernel: Map special regions according to ExHeader

This replaces the hardcoded VRAM/DSP mappings with ones made based on
the ExHeader ARM11 Kernel caps list. While this has no visible effect
for most applications (since they use a standard set of mappings) it
does improve support for system modules and n3DS exclusives.

src/core/core.cpp

@@ -13,11 +13,11 @@
 #include "core/core_timing.h"
 #include "core/gdbstub/gdbstub.h"
 #include "core/hle/kernel/kernel.h"
-#include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/thread.h"
 #include "core/hle/service/service.h"
 #include "core/hw/hw.h"
 #include "core/loader/loader.h"
+#include "core/memory_setup.h"
 #include "core/settings.h"
 #include "video_core/video_core.h"
 
@@ -123,7 +123,8 @@ void System::Reschedule() {
 }
 
 System::ResultStatus System::Init(EmuWindow* emu_window, u32 system_mode) {
-    Memory::Init();
+    Memory::InitMemoryMap();
+    LOG_DEBUG(HW_Memory, "initialized OK");
 
     if (Settings::values.use_cpu_jit) {
         cpu_core = std::make_unique<ARM_Dynarmic>(USER32MODE);

src/core/hle/kernel/memory.cpp

@@ -2,11 +2,13 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <cinttypes>
 #include <map>
 #include <memory>
 #include <utility>
 #include <vector>
 #include "audio_core/audio_core.h"
+#include "common/assert.h"
 #include "common/common_types.h"
 #include "common/logging/log.h"
 #include "core/hle/config_mem.h"
@@ -92,57 +94,96 @@ MemoryRegionInfo* GetMemoryRegion(MemoryRegion region) {
         UNREACHABLE();
     }
 }
-}
 
-namespace Memory {
+std::array<u8, Memory::VRAM_SIZE> vram;
+std::array<u8, Memory::N3DS_EXTRA_RAM_SIZE> n3ds_extra_ram;
 
-namespace {
+void HandleSpecialMapping(VMManager& address_space, const AddressMapping& mapping) {
+    using namespace Memory;
 
-struct MemoryArea {
-    u32 base;
-    u32 size;
-    const char* name;
-};
+    struct MemoryArea {
+        VAddr vaddr_base;
+        PAddr paddr_base;
+        u32 size;
+    };
 
-// We don't declare the IO regions in here since its handled by other means.
-static MemoryArea memory_areas[] = {
-    {VRAM_VADDR, VRAM_SIZE, "VRAM"}, // Video memory (VRAM)
-};
-}
+    // The order of entries in this array is important. The VRAM and IO VAddr ranges overlap, and
+    // VRAM must be tried first.
+    static constexpr MemoryArea memory_areas[] = {
+        {VRAM_VADDR, VRAM_PADDR, VRAM_SIZE},
+        {IO_AREA_VADDR, IO_AREA_PADDR, IO_AREA_SIZE},
+        {DSP_RAM_VADDR, DSP_RAM_PADDR, DSP_RAM_SIZE},
+        {N3DS_EXTRA_RAM_VADDR, N3DS_EXTRA_RAM_PADDR, N3DS_EXTRA_RAM_SIZE - 0x20000},
+    };
 
-void Init() {
-    InitMemoryMap();
-    LOG_DEBUG(HW_Memory, "initialized OK");
-}
-
-void InitLegacyAddressSpace(Kernel::VMManager& address_space) {
-    using namespace Kernel;
-
-    for (MemoryArea& area : memory_areas) {
-        auto block = std::make_shared<std::vector<u8>>(area.size);
-        address_space
-            .MapMemoryBlock(area.base, std::move(block), 0, area.size, MemoryState::Private)
-            .Unwrap();
+    VAddr mapping_limit = mapping.address + mapping.size;
+    if (mapping_limit < mapping.address) {
+        LOG_CRITICAL(Loader, "Mapping size overflowed: address=0x%08" PRIX32 " size=0x%" PRIX32,
+                     mapping.address, mapping.size);
+        return;
     }
 
+    auto area =
+        std::find_if(std::begin(memory_areas), std::end(memory_areas), [&](const auto& area) {
+            return mapping.address >= area.vaddr_base &&
+                   mapping_limit <= area.vaddr_base + area.size;
+        });
+    if (area == std::end(memory_areas)) {
+        LOG_ERROR(Loader, "Unhandled special mapping: address=0x%08" PRIX32 " size=0x%" PRIX32
+                          " read_only=%d unk_flag=%d",
+                  mapping.address, mapping.size, mapping.read_only, mapping.unk_flag);
+        return;
+    }
+
+    u32 offset_into_region = mapping.address - area->vaddr_base;
+    if (area->paddr_base == IO_AREA_PADDR) {
+        LOG_ERROR(Loader, "MMIO mappings are not supported yet. phys_addr=0x%08" PRIX32,
+                  area->paddr_base + offset_into_region);
+        return;
+    }
+
+    // TODO(yuriks): Use GetPhysicalPointer when that becomes independent of the virtual
+    // mappings.
+    u8* target_pointer = nullptr;
+    switch (area->paddr_base) {
+    case VRAM_PADDR:
+        target_pointer = vram.data();
+        break;
+    case DSP_RAM_PADDR:
+        target_pointer = AudioCore::GetDspMemory().data();
+        break;
+    case N3DS_EXTRA_RAM_PADDR:
+        target_pointer = n3ds_extra_ram.data();
+        break;
+    default:
+        UNREACHABLE();
+    }
+
+    // TODO(yuriks): This flag seems to have some other effect, but it's unknown what
+    MemoryState memory_state = mapping.unk_flag ? MemoryState::Static : MemoryState::IO;
+
+    auto vma = address_space
+                   .MapBackingMemory(mapping.address, target_pointer + offset_into_region,
+                                     mapping.size, memory_state)
+                   .MoveFrom();
+    address_space.Reprotect(vma,
+                            mapping.read_only ? VMAPermission::Read : VMAPermission::ReadWrite);
+}
+
+void MapSharedPages(VMManager& address_space) {
     auto cfg_mem_vma = address_space
-                           .MapBackingMemory(CONFIG_MEMORY_VADDR, (u8*)&ConfigMem::config_mem,
-                                             CONFIG_MEMORY_SIZE, MemoryState::Shared)
+                           .MapBackingMemory(Memory::CONFIG_MEMORY_VADDR,
+                                             reinterpret_cast<u8*>(&ConfigMem::config_mem),
+                                             Memory::CONFIG_MEMORY_SIZE, MemoryState::Shared)
                            .MoveFrom();
     address_space.Reprotect(cfg_mem_vma, VMAPermission::Read);
 
     auto shared_page_vma = address_space
-                               .MapBackingMemory(SHARED_PAGE_VADDR, (u8*)&SharedPage::shared_page,
-                                                 SHARED_PAGE_SIZE, MemoryState::Shared)
+                               .MapBackingMemory(Memory::SHARED_PAGE_VADDR,
+                                                 reinterpret_cast<u8*>(&SharedPage::shared_page),
+                                                 Memory::SHARED_PAGE_SIZE, MemoryState::Shared)
                                .MoveFrom();
     address_space.Reprotect(shared_page_vma, VMAPermission::Read);
-
-    auto& dsp_ram = AudioCore::GetDspMemory();
-    auto dsp_vma = address_space
-                       .MapBackingMemory(DSP_RAM_VADDR, dsp_ram.data(), dsp_ram.size(),
-                                         Kernel::MemoryState::IO)
-                       .MoveFrom();
-    address_space.Reprotect(dsp_vma, Kernel::VMAPermission::ReadWrite);
 }
 
-} // namespace
+} // namespace Kernel

src/core/hle/kernel/memory.h

@@ -23,11 +23,7 @@ struct MemoryRegionInfo {
 void MemoryInit(u32 mem_type);
 void MemoryShutdown();
 MemoryRegionInfo* GetMemoryRegion(MemoryRegion region);
-}
 
-namespace Memory {
-
-void Init();
-void InitLegacyAddressSpace(Kernel::VMManager& address_space);
-
-} // namespace
+void HandleSpecialMapping(VMManager& address_space, const AddressMapping& mapping);
+void MapSharedPages(VMManager& address_space);
+} // namespace Kernel

src/core/hle/kernel/process.cpp

@@ -35,7 +35,6 @@ SharedPtr<Process> Process::Create(SharedPtr<CodeSet> code_set) {
     process->codeset = std::move(code_set);
     process->flags.raw = 0;
     process->flags.memory_region.Assign(MemoryRegion::APPLICATION);
-    Memory::InitLegacyAddressSpace(process->vm_manager);
 
     return process;
 }
@@ -78,8 +77,15 @@ void Process::ParseKernelCaps(const u32* kernel_caps, size_t len) {
 
             AddressMapping mapping;
             mapping.address = descriptor << 12;
-            mapping.size = (end_desc << 12) - mapping.address;
-            mapping.writable = (descriptor & (1 << 20)) != 0;
+            VAddr end_address = end_desc << 12;
+
+            if (mapping.address < end_address) {
+                mapping.size = end_address - mapping.address;
+            } else {
+                mapping.size = 0;
+            }
+
+            mapping.read_only = (descriptor & (1 << 20)) != 0;
             mapping.unk_flag = (end_desc & (1 << 20)) != 0;
 
             address_mappings.push_back(mapping);
@@ -88,8 +94,10 @@ void Process::ParseKernelCaps(const u32* kernel_caps, size_t len) {
             AddressMapping mapping;
             mapping.address = descriptor << 12;
             mapping.size = Memory::PAGE_SIZE;
-            mapping.writable = true; // TODO: Not sure if correct
+            mapping.read_only = false;
             mapping.unk_flag = false;
+
+            address_mappings.push_back(mapping);
         } else if ((type & 0xFE0) == 0xFC0) { // 0x01FF
             // Kernel version
             kernel_version = descriptor & 0xFFFF;
@@ -131,6 +139,12 @@ void Process::Run(s32 main_thread_priority, u32 stack_size) {
     misc_memory_used += stack_size;
     memory_region->used += stack_size;
 
+    // Map special address mappings
+    MapSharedPages(vm_manager);
+    for (const auto& mapping : address_mappings) {
+        HandleSpecialMapping(vm_manager, mapping);
+    }
+
     vm_manager.LogLayout(Log::Level::Debug);
     Kernel::SetupMainThread(codeset->entrypoint, main_thread_priority);
 }
@@ -138,6 +152,7 @@ void Process::Run(s32 main_thread_priority, u32 stack_size) {
 VAddr Process::GetLinearHeapAreaAddress() const {
     return kernel_version < 0x22C ? Memory::LINEAR_HEAP_VADDR : Memory::NEW_LINEAR_HEAP_VADDR;
 }
+
 VAddr Process::GetLinearHeapBase() const {
     return GetLinearHeapAreaAddress() + memory_region->base;
 }

src/core/hle/kernel/process.h

@@ -20,7 +20,7 @@ struct AddressMapping {
     // Address and size must be page-aligned
     VAddr address;
     u32 size;
-    bool writable;
+    bool read_only;
     bool unk_flag;
 };