nvnflinger: allow locking framerate during video playback

src/core/core.cpp

@@ -216,6 +216,14 @@ struct System::Impl {
         }
     }
 
+    void SetNVDECActive(bool is_nvdec_active) {
+        nvdec_active = is_nvdec_active;
+    }
+
+    bool GetNVDECActive() {
+        return nvdec_active;
+    }
+
     void InitializeDebugger(System& system, u16 port) {
         debugger = std::make_unique<Debugger>(system, port);
     }
@@ -485,6 +493,8 @@ struct System::Impl {
     std::atomic_bool is_powered_on{};
     bool exit_lock = false;
 
+    bool nvdec_active{};
+
     Reporter reporter;
     std::unique_ptr<Memory::CheatEngine> cheat_engine;
     std::unique_ptr<Tools::Freezer> memory_freezer;
@@ -594,6 +604,14 @@ void System::UnstallApplication() {
     impl->UnstallApplication();
 }
 
+void System::SetNVDECActive(bool is_nvdec_active) {
+    impl->SetNVDECActive(is_nvdec_active);
+}
+
+bool System::GetNVDECActive() {
+    return impl->GetNVDECActive();
+}
+
 void System::InitializeDebugger() {
     impl->InitializeDebugger(*this, Settings::values.gdbstub_port.GetValue());
 }

src/core/core.h

@@ -189,6 +189,9 @@ public:
     std::unique_lock<std::mutex> StallApplication();
     void UnstallApplication();
 
+    void SetNVDECActive(bool is_nvdec_active);
+    [[nodiscard]] bool GetNVDECActive();
+
     /**
      * Initialize the debugger.
      */

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

@@ -69,7 +69,7 @@ NvResult nvhost_nvdec::Ioctl3(DeviceFD fd, Ioctl command, std::span<const u8> in
 
 void nvhost_nvdec::OnOpen(DeviceFD fd) {
     LOG_INFO(Service_NVDRV, "NVDEC video stream started");
-    system.AudioCore().SetNVDECActive(true);
+    system.SetNVDECActive(true);
 }
 
 void nvhost_nvdec::OnClose(DeviceFD fd) {
@@ -79,7 +79,7 @@ void nvhost_nvdec::OnClose(DeviceFD fd) {
     if (iter != host1x_file.fd_to_id.end()) {
         system.GPU().ClearCdmaInstance(iter->second);
     }
-    system.AudioCore().SetNVDECActive(false);
+    system.SetNVDECActive(false);
 }
 
 } // namespace Service::Nvidia::Devices

src/core/hle/service/nvnflinger/nvnflinger.cpp

@@ -324,6 +324,10 @@ s64 Nvnflinger::GetNextTicks() const {
             speed_scale = 0.01f;
         }
     }
+    if (system.GetNVDECActive() && settings.use_video_framerate.GetValue()) {
+        // Run at intended presentation rate during video playback.
+        speed_scale = 1.f;
+    }
 
     // As an extension, treat nonpositive swap interval as framerate multiplier.
     const f32 effective_fps = swap_interval <= 0 ? 120.f * static_cast<f32>(1 - swap_interval)