[service, nvhost] added machinery to allow microsleep between nvdec read requests to avoid guest panic in some games (#4316)

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------
This one deserves a long story, but imma try to resume:

During investigating Absolum 1.2 black screen of death upon loading intro video, i've discovered guest was aborting for failing to allocate room for the video.

By logging everything prior to crash and decoding guest side instructions managed to confirm its media allocator was reading data faster than it was updating free available bucket list.

Since the IStorage::Read was happening 247 times before the crash, i've decided to add a very small sleep there, and boom, not only Absolum but some other titles got the same issue fixed.

But i was unsatisfied with the sleep and kept tracking guest instructions upstream in order to find a sync point for the read worker and the memory allocation update. But unfortunately the media allocator helpers live in guest, accessing memory directly via MMU, so any sync signaling would need to come from some dynarmic hack.

It's been 6 days now, so i've decided to polish the sleep: Moved it upstream to where i could have access for proper predicate, and added machinery to service and nvhost to support that. Now the sleep is restricted only for nvdec istorage reads. Any other reads will flow normally.

TL;DR: currently our code is so blazing async that guest is capable to request reads before its very self refresh it have freed room to do so. The sleep accepted as broadly stable was 600 us (MICROseconds), and it affects ONLY nvdec chunk reading.
Reports confirm that now videos are smoother now.

Code was polished at my knowledge limits.
Mostly machinery to track when a request comes from a process with nvdec active, and is istorage read.
I can provide more details if it comes to be needed.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4316
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: Samuel <lizzie@eden-emu.dev>

docs/Settings.md

@@ -43,7 +43,6 @@ This guide will walk you through adding a new boolean toggle setting to Eden's c
 Firstly add your desired toggle:
 
 Example: `src/common/setting.h`
-
 ```cpp
 SwitchableSetting<bool> your_setting_name{linkage, false, "your_setting_name", Category::RendererExtensions};
 ```
@@ -68,7 +67,6 @@ Common Categories:
 Add the toggle to the Qt UI, where you wish for it to appear and place it there.
 
 Example: `src/qt_common/config/shared_translation.cpp`
-
 ```cpp
 INSERT(Settings,
        your_setting_name,
@@ -93,7 +91,6 @@ INSERT(Settings,
 Add where it should be in the settings.
 
 Example: `src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/BooleanSetting.kt`
-
 ```kts
 RENDERER_YOUR_SETTING_NAME("your_setting_name"),
 ```
@@ -109,7 +106,6 @@ RENDERER_YOUR_SETTING_NAME("your_setting_name"),
 Add the toggle to the Kotlin (Android) UI
 
 Example: `src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/view/SettingsItem.kt`
-
 ```kts
 put(
     SwitchSetting(
@@ -127,7 +123,6 @@ put(
 Add your setting within the right category.
 
 Example: `src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/ui/SettingsFragmentPresenter.kt`
-
 ```kts
 add(BooleanSetting.RENDERER_YOUR_SETTING_NAME.key)
 ```
@@ -142,7 +137,6 @@ add(BooleanSetting.RENDERER_YOUR_SETTING_NAME.key)
 Add your setting and description in the appropriate place.
 
 Example: `src/android/app/src/main/res/values/strings.xml`
-
 ```xml
 <string name="your_setting_name">Your Setting Display Name</string>
 <string name="your_setting_name_description">Detailed description of what this setting does. Explain any caveats, requirements, or warnings here.</string>
@@ -156,7 +150,6 @@ Now the UI part is done find a place in the code for the toggle,
 And use it to your heart's desire!
 
 Example:
-
 ```cpp
 const bool your_value = Settings::values.your_setting_name.GetValue();
 
@@ -203,31 +196,25 @@ Common advantages recap:
 
 #### Accessing Debug Knobs (dev side)
 
-Use the `Settings::GetDebugKnobAt(u8 i)` function to check if a specific bit is set:
+Use the `Settings::getDebugKnobAt(u8 i)` function to check if a specific bit is set:
 
 ```cpp
 //cpp side
 #include "common/settings.h"
 
-//To use it as a general purpose uint var:
-unsigned int debug_knobs = Settings::values.debug_knobs.GetValue();
-
 // Check if bit 0 is set
-bool feature_enabled = Settings::GetDebugKnobAt(0);
+bool feature_enabled = Settings::getDebugKnobAt(0);
 
 // Check if bit 15 is set
-bool another_feature = Settings::GetDebugKnobAt(15);
+bool another_feature = Settings::getDebugKnobAt(15);
 ```
 
 ```kts
 //kotlin side
 import org.yuzu.yuzu_emu.features.settings.model.Settings
 
-//To use it as a general purpose uint var
-val debug_knobs: Int = UShortSetting.DEBUG_KNOBS.getInt()
-
 // Check if bit x is set
-bool feature_enabled = Settings.GetDebugKnobAt(x); //x as integer from 0 to 15
+bool feature_enabled = Settings.getDebugKnobAt(x); //x as integer from 0 to 15
 ```
 
 The function returns `true` if the specified bit (0-15) is set in the `debug_knobs` value, `false` otherwise.
@@ -260,7 +247,6 @@ There are two main confusions when talking about knobs:
 Sometimes when an user reports: knobs 1 and 2 gets better performance, dev may get confuse whether he means the knobs 1 and 2 literally, or the 1st and 2nd knobs (knobs 0 and 1).
 
 Debug knobs are **zero-based**, which means:
-
 * The first knob is the knob(0) (or knob0 henceforth), and the last one is the 15 (knob15, likewise)
 * You can talk: "knob0 is enabled/disabled", "In this video i was using only knobs 0 and 2", etc.
 
@@ -273,7 +259,6 @@ Whenever you're instructing tests or reporting results, be precise about whether
 
 ALWAYS use the word in PLURAL (knobs), without mentioning which one, to refer to the setting, aka multiple knobs at once:
 Examples:
-
 - **knobs=0**: no knobs enabled
 - **knobs=1**: knob0 enabled, others disabled
 - **knobs=2**: knob1 enabled, others disabled
@@ -285,7 +270,6 @@ Examples:
 
 Use the word in SINGULAR (knob), or in plural but referring which ones, when meaning multiple knobs at once:
 Examples:
-
 - **knob0**: knob 0 enabled, others disabled
 - **knob1**: knob 1 enabled, others disabled
 - **knobs 0 and 1**: knobs 0 and 1 enabled, others disabled
@@ -298,12 +282,12 @@ Examples:
 
 ```cpp
 void SomeFunction() {
-    if (Settings::GetDebugKnobAt(0)) {
+    if (Settings::getDebugKnobAt(0)) {
         LOG_DEBUG(Common, "Debug feature 0 is enabled");
         // Additional debug code here
     }
-  
+    
-    if (Settings::GetDebugKnobAt(1)) {
+    if (Settings::getDebugKnobAt(1)) {
         LOG_DEBUG(Common, "Debug feature 1 is enabled");
         // Different debug behavior
     }
@@ -315,7 +299,7 @@ void SomeFunction() {
 ```cpp
 bool UseOptimizedPath() {
     // Skip optimization if debug bit 2 is set for testing
-    return !Settings::GetDebugKnobAt(2);
+    return !Settings::getDebugKnobAt(2);
 }
 ```
 
@@ -324,13 +308,13 @@ bool UseOptimizedPath() {
 ```cpp
 void ExperimentalFeature() {
     static constexpr u8 EXPERIMENTAL_FEATURE_BIT = 3;
-  
+    
-    if (!Settings::GetDebugKnobAt(EXPERIMENTAL_FEATURE_BIT)) {
+    if (!Settings::getDebugKnobAt(EXPERIMENTAL_FEATURE_BIT)) {
         // Fallback to stable implementation
         StableImplementation();
         return;
     }
-  
+    
     // Experimental implementation
     ExperimentalImplementation();
 }

src/android/app/src/main/java/org/yuzu/yuzu_emu/NativeLibrary.kt

@@ -220,7 +220,7 @@ object NativeLibrary {
 
     external fun refreshThreadPolicies()
 
-    external fun GetDebugKnobAt(index: Int): Boolean
+    external fun getDebugKnobAt(index: Int): Boolean
 
     /**
      * Set the current speed limit to the configured turbo speed.

src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/Settings.kt

@@ -35,8 +35,8 @@ object Settings {
     fun getPlayerString(player: Int): String =
         YuzuApplication.appContext.getString(R.string.preferences_player, player)
 
-    fun GetDebugKnobAt(index: Int): Boolean {
+    fun getDebugKnobAt(index: Int): Boolean {
-        return org.yuzu.yuzu_emu.NativeLibrary.GetDebugKnobAt(index)
+        return org.yuzu.yuzu_emu.NativeLibrary.getDebugKnobAt(index)
     }
 
     const val PREF_FIRST_APP_LAUNCH = "FirstApplicationLaunch"

src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/ShortSetting.kt

@@ -11,7 +11,8 @@ import org.yuzu.yuzu_emu.utils.NativeConfig
 enum class ShortSetting(override val key: String) : AbstractShortSetting {
     RENDERER_SPEED_LIMIT("speed_limit"),
     RENDERER_TURBO_SPEED_LIMIT("turbo_speed_limit"),
-    RENDERER_SLOW_SPEED_LIMIT("slow_speed_limit")
+    RENDERER_SLOW_SPEED_LIMIT("slow_speed_limit"),
+    DEBUG_KNOBS("debug_knobs")
     ;
 
     override fun getShort(needsGlobal: Boolean): Short = NativeConfig.getShort(key, needsGlobal)
@@ -28,4 +29,4 @@ enum class ShortSetting(override val key: String) : AbstractShortSetting {
     override fun getValueAsString(needsGlobal: Boolean): String = getShort(needsGlobal).toString()
 
     override fun reset() = NativeConfig.setShort(key, defaultValue)
-}
+}

src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/UShortSetting.kt

@@ -1,30 +0,0 @@
-// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
-// SPDX-License-Identifier: GPL-3.0-or-later
-
-// SPDX-FileCopyrightText: 2023 yuzu Emulator Project
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-package org.yuzu.yuzu_emu.features.settings.model
-
-import org.yuzu.yuzu_emu.utils.NativeConfig
-
-enum class UShortSetting(override val key: String) : AbstractIntSetting {
-    DEBUG_KNOBS("debug_knobs")
-    ;
-
-    override fun getInt(needsGlobal: Boolean): Int =
-        NativeConfig.getUnsignedShort(key, needsGlobal)
-
-    override fun setInt(value: Int) {
-        if (NativeConfig.isPerGameConfigLoaded()) {
-            global = false
-        }
-        NativeConfig.setUnsignedShort(key, value)
-    }
-
-    override val defaultValue: Int by lazy { NativeConfig.getDefaultToString(key).toInt() }
-
-    override fun getValueAsString(needsGlobal: Boolean): String = getInt(needsGlobal).toString()
-
-    override fun reset() = NativeConfig.setUnsignedShort(key, defaultValue)
-}

src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/model/view/SettingsItem.kt

@@ -20,7 +20,6 @@ import org.yuzu.yuzu_emu.features.settings.model.IntSetting
 import org.yuzu.yuzu_emu.features.settings.model.LongSetting
 import org.yuzu.yuzu_emu.features.settings.model.ShortSetting
 import org.yuzu.yuzu_emu.features.settings.model.StringSetting
-import org.yuzu.yuzu_emu.features.settings.model.UShortSetting
 import org.yuzu.yuzu_emu.network.NetDataValidators
 import org.yuzu.yuzu_emu.utils.LosslessScalingHelper
 import org.yuzu.yuzu_emu.utils.NativeConfig
@@ -1035,7 +1034,7 @@ abstract class SettingsItem(
             )
             put(
                 SpinBoxSetting(
-                    UShortSetting.DEBUG_KNOBS,
+                    ShortSetting.DEBUG_KNOBS,
                     titleId = R.string.debug_knobs,
                     descriptionId = R.string.debug_knobs_description,
                     valueHint = R.string.debug_knobs_hint,

src/android/app/src/main/java/org/yuzu/yuzu_emu/features/settings/ui/SettingsFragmentPresenter.kt

@@ -25,7 +25,6 @@ import org.yuzu.yuzu_emu.features.settings.model.Settings
 import org.yuzu.yuzu_emu.features.settings.model.Settings.MenuTag
 import org.yuzu.yuzu_emu.features.settings.model.ShortSetting
 import org.yuzu.yuzu_emu.features.settings.model.StringSetting
-import org.yuzu.yuzu_emu.features.settings.model.UShortSetting
 import org.yuzu.yuzu_emu.features.settings.model.view.*
 import org.yuzu.yuzu_emu.utils.InputHandler
 import org.yuzu.yuzu_emu.utils.LosslessScalingHelper
@@ -1327,7 +1326,7 @@ class SettingsFragmentPresenter(
 
             add(HeaderSetting(R.string.general))
 
-            add(UShortSetting.DEBUG_KNOBS.key)
+            add(ShortSetting.DEBUG_KNOBS.key)
             add(StringSetting.PROGRAM_ARGS.key)
 
             if (!NativeConfig.isPerGameConfigLoaded()) {

src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/NativeConfig.kt

@@ -80,12 +80,6 @@ object NativeConfig {
     @Synchronized
     external fun setShort(key: String, value: Short)
 
-    @Synchronized
-    external fun getUnsignedShort(key: String, needsGlobal: Boolean): Int
-
-    @Synchronized
-    external fun setUnsignedShort(key: String, value: Int)
-
     @Synchronized
     external fun getInt(key: String, needsGlobal: Boolean): Int
 

src/android/app/src/main/jni/native.cpp

@@ -1300,8 +1300,8 @@ void Java_org_yuzu_yuzu_1emu_NativeLibrary_refreshThreadPolicies(JNIEnv* env, jo
     Common::RefreshThreadPolicies();
 }
 
-jboolean Java_org_yuzu_yuzu_1emu_NativeLibrary_GetDebugKnobAt(JNIEnv* env, jobject jobj, jint index) {
+jboolean Java_org_yuzu_yuzu_1emu_NativeLibrary_getDebugKnobAt(JNIEnv* env, jobject jobj, jint index) {
-    return static_cast<jboolean>(Settings::GetDebugKnobAt(static_cast<u8>(index)));
+    return static_cast<jboolean>(Settings::getDebugKnobAt(static_cast<u8>(index)));
 }
 
 void Java_org_yuzu_yuzu_1emu_NativeLibrary_setTurboSpeedLimit(JNIEnv *env, jobject jobj, jboolean enabled) {

src/android/app/src/main/jni/native_config.cpp

@@ -130,25 +130,6 @@ void Java_org_yuzu_yuzu_1emu_utils_NativeConfig_setShort(JNIEnv* env, jobject ob
     setting->SetValue(value);
 }
 
-jint Java_org_yuzu_yuzu_1emu_utils_NativeConfig_getUnsignedShort(JNIEnv* env, jobject obj,
-                                                                 jstring jkey,
-                                                                 jboolean needGlobal) {
-    auto setting = getSetting<u16>(env, jkey);
-    if (setting == nullptr) {
-        return -1;
-    }
-    return static_cast<jint>(setting->GetValue(static_cast<bool>(needGlobal)));
-}
-
-void Java_org_yuzu_yuzu_1emu_utils_NativeConfig_setUnsignedShort(JNIEnv* env, jobject obj,
-                                                                  jstring jkey, jint value) {
-    auto setting = getSetting<u16>(env, jkey);
-    if (setting == nullptr) {
-        return;
-    }
-    setting->SetValue(static_cast<u16>(value));
-}
-
 jint Java_org_yuzu_yuzu_1emu_utils_NativeConfig_getInt(JNIEnv* env, jobject obj, jstring jkey,
                                                        jboolean needGlobal) {
     auto setting = getSetting<int>(env, jkey);

src/common/settings.cpp

@@ -146,7 +146,7 @@ void LogSettings() {
 #undef LOG_PATH
 }
 
-bool GetDebugKnobAt(u8 i) {
+bool getDebugKnobAt(u8 i) {
     return (values.debug_knobs.GetValue() & (1 << (i & 0xF))) != 0;
 }
 

src/common/settings.h

@@ -904,7 +904,7 @@ struct Values {
                                            0,
                                            65535,
                                            "debug_knobs",
-                                           Category::System,
+                                           Category::Debugging,
                                            Specialization::Countable,
                                            true,
                                            true};
@@ -947,7 +947,7 @@ constexpr u32 MAX_FRAME_GEN_MULTIPLIER = 4;
 
 [[nodiscard]] size_t FrameGenMaxGenerations();
 
-bool GetDebugKnobAt(u8 i);
+bool getDebugKnobAt(u8 i);
 
 void UpdateGPUAccuracy();
 bool IsGPULevelHigh();

src/core/core.cpp

@@ -4,6 +4,7 @@
 #include <array>
 #include <atomic>
 #include <memory>
+#include <unordered_map>
 #include <utility>
 
 #include "game_settings.h"
@@ -248,12 +249,30 @@ struct System::Impl {
         }
     }
 
-    void SetNVDECActive(bool is_nvdec_active) {
+    void NotifyNVDECChannelOpen(u64 process_id) {
-        nvdec_active = is_nvdec_active;
+        std::scoped_lock lock{nvdec_active_mutex};
+        ++nvdec_active_channels[process_id];
+    }
+
+    void NotifyNVDECChannelClose(u64 process_id) {
+        std::scoped_lock lock{nvdec_active_mutex};
+        const auto it = nvdec_active_channels.find(process_id);
+        if (it == nvdec_active_channels.end()) {
+            return;
+        }
+        if (--it->second == 0) {
+            nvdec_active_channels.erase(it);
+        }
     }
 
     bool GetNVDECActive() {
-        return nvdec_active;
+        std::scoped_lock lock{nvdec_active_mutex};
+        return !nvdec_active_channels.empty();
+    }
+
+    bool IsNVDECActiveForProcess(u64 process_id) {
+        std::scoped_lock lock{nvdec_active_mutex};
+        return nvdec_active_channels.contains(process_id);
     }
 
     void InitializeDebugger(System& system, u16 port) {
@@ -505,6 +524,8 @@ struct System::Impl {
 
     mutable std::mutex suspend_guard;
     std::mutex general_channel_mutex;
+    std::mutex nvdec_active_mutex;
+    std::unordered_map<u64, u32> nvdec_active_channels;
     std::atomic_bool is_paused{};
     std::atomic_bool is_shutting_down{};
     std::atomic_bool is_powered_on{};
@@ -512,7 +533,6 @@ struct System::Impl {
     bool extended_memory_layout : 1 = false;
     bool exit_locked : 1 = false;
     bool exit_requested : 1 = false;
-    bool nvdec_active : 1 = false;
 
     void EnsureGeneralChannelInitialized(System& system) {
         if (!general_channel_event) {
@@ -576,14 +596,22 @@ void System::UnstallApplication() {
     impl->UnstallApplication();
 }
 
-void System::SetNVDECActive(bool is_nvdec_active) {
+void System::NotifyNVDECChannelOpen(u64 process_id) {
-    impl->SetNVDECActive(is_nvdec_active);
+    impl->NotifyNVDECChannelOpen(process_id);
+}
+
+void System::NotifyNVDECChannelClose(u64 process_id) {
+    impl->NotifyNVDECChannelClose(process_id);
 }
 
 bool System::GetNVDECActive() {
     return impl->GetNVDECActive();
 }
 
+bool System::IsNVDECActiveForProcess(u64 process_id) {
+    return impl->IsNVDECActiveForProcess(process_id);
+}
+
 void System::InitializeDebugger() {
     impl->InitializeDebugger(*this, Settings::values.gdbstub_port.GetValue());
 }

src/core/core.h

@@ -191,8 +191,10 @@ public:
     std::unique_lock<std::mutex> StallApplication();
     void UnstallApplication();
 
-    void SetNVDECActive(bool is_nvdec_active);
+    void NotifyNVDECChannelOpen(u64 process_id);
+    void NotifyNVDECChannelClose(u64 process_id);
     [[nodiscard]] bool GetNVDECActive();
+    [[nodiscard]] bool IsNVDECActiveForProcess(u64 process_id);
 
     /**
      * Initialize the debugger.

src/core/hle/service/nvdrv/devices/nvhost_nvdec.cpp

@@ -8,6 +8,7 @@
 #include "common/assert.h"
 #include "common/logging.h"
 #include "core/core.h"
+#include "core/hle/kernel/k_process.h"
 #include "core/hle/service/nvdrv/core/container.h"
 #include "core/hle/service/nvdrv/devices/ioctl_serialization.h"
 #include "core/hle/service/nvdrv/devices/nvhost_nvdec.h"
@@ -71,17 +72,23 @@ NvResult nvhost_nvdec::Ioctl3(DeviceFD fd, Ioctl command, std::span<const u8> in
 
 void nvhost_nvdec::OnOpen(NvCore::SessionId session_id, DeviceFD fd) {
     LOG_INFO(Service_NVDRV, "NVDEC video stream started");
-    system.SetNVDECActive(true);
     sessions[fd] = session_id;
+    if (const auto* session = core.GetSession(session_id);
+        session != nullptr && session->process != nullptr) {
+        system.NotifyNVDECChannelOpen(session->process->GetId());
+    }
     host1x.StartDevice(fd, Tegra::Host1x::ChannelType::NvDec, channel_syncpoint);
 }
 
 void nvhost_nvdec::OnClose(DeviceFD fd) {
     LOG_INFO(Service_NVDRV, "NVDEC video stream ended");
     host1x.StopDevice(fd, Tegra::Host1x::ChannelType::NvDec);
-    system.SetNVDECActive(false);
     auto it = sessions.find(fd);
     if (it != sessions.end()) {
+        if (const auto* session = core.GetSession(it->second);
+            session != nullptr && session->process != nullptr) {
+            system.NotifyNVDECChannelClose(session->process->GetId());
+        }
         sessions.erase(it);
     }
 }

src/core/hle/service/service.cpp

@@ -4,12 +4,16 @@
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
+#include <chrono>
 #include <fmt/ranges.h>
+#include <string_view>
+#include <thread>
 #include "common/assert.h"
 #include "common/logging.h"
 #include "common/settings.h"
 #include "core/core.h"
 #include "core/hle/ipc.h"
+#include "core/hle/kernel/k_process.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/service/ipc_helpers.h"
 #include "core/hle/service/service.h"
@@ -33,6 +37,7 @@ ServiceFrameworkBase::ServiceFrameworkBase(Core::System& system_, const char* se
     : SessionRequestHandler(system_.Kernel(), service_name_)
     , system{system_}
     , service_name{service_name_}
+    , is_i_storage{std::string_view{service_name_} == "IStorage"}
     , handler_invoker{handler_invoker_}
     , max_sessions{max_sessions_}
 {}
@@ -77,13 +82,22 @@ void ServiceFrameworkBase::ReportUnimplementedFunction(HLERequestContext& ctx,
 }
 
 void ServiceFrameworkBase::InvokeRequest(HLERequestContext& ctx) {
-    auto it = handlers.find(ctx.GetCommand());
+    const auto command = ctx.GetCommand();
+    auto it = handlers.find(command);
+    const bool is_cmd_read = command == 0;
     FunctionInfoBase const* info = it == handlers.end() ? nullptr : &it->second;
     if (info == nullptr || info->handler_callback == nullptr)
         return ReportUnimplementedFunction(ctx, info);
 
     LOG_TRACE(Service, "{}", MakeFunctionString(info->name, GetServiceName(), ctx.CommandBuffer()));
     handler_invoker(this, info->handler_callback, ctx);
+
+    if (is_i_storage && is_cmd_read) {
+        const auto* const process = ctx.GetThread().GetOwnerProcess();
+        if (process != nullptr && system.IsNVDECActiveForProcess(process->GetId())) {
+            std::this_thread::sleep_for(std::chrono::microseconds{600});
+        }
+    }
 }
 
 void ServiceFrameworkBase::InvokeRequestTipc(HLERequestContext& ctx) {

src/core/hle/service/service.h

@@ -107,6 +107,8 @@ protected:
     Core::System& system;
     /// Identifier string used to connect to the service.
     const char* service_name;
+    /// Whether this is the IStorage service.
+    const bool is_i_storage;
     /// Function used to safely up-cast pointers to the derived class before invoking a handler.
     InvokerFn* handler_invoker;
     /// Maximum number of concurrent sessions that this service can handle.