nvnflinger/gpu: implement layer stack composition

1 files changed, 59 insertions, 0 deletions

diff --git a/src/core/hle/service/nvnflinger/hardware_composer.h b/src/core/hle/service/nvnflinger/hardware_composer.h
new file mode 100644
index 000000000..611afc169
--- /dev/null
+++ b/src/core/hle/service/nvnflinger/hardware_composer.h
@@ -0,0 +1,59 @@
+// SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <memory>
+#include <boost/container/flat_map.hpp>
+
+#include "core/hle/service/nvnflinger/buffer_item.h"
+
+namespace Service::Nvidia::Devices {
+class nvdisp_disp0;
+}
+
+namespace Service::VI {
+class Display;
+class Layer;
+} // namespace Service::VI
+
+namespace Service::Nvnflinger {
+
+using LayerId = u64;
+
+class HardwareComposer {
+public:
+    explicit HardwareComposer();
+    ~HardwareComposer();
+
+    u32 ComposeLocked(VI::Display& display, Nvidia::Devices::nvdisp_disp0& nvdisp,
+                      u32 frame_advance);
+    void RemoveLayerLocked(VI::Display& display, LayerId layer_id);
+
+private:
+    // TODO: do we want to track frame number in vi instead?
+    u64 m_frame_number{0};
+
+private:
+    using ReleaseFrameNumber = u64;
+
+    struct Framebuffer {
+        android::BufferItem item{};
+        ReleaseFrameNumber release_frame_number{};
+        bool is_acquired{false};
+    };
+
+    enum class CacheStatus : u32 {
+        NoBufferAvailable,
+        BufferAcquired,
+        CachedBufferReused,
+    };
+
+    boost::container::flat_map<LayerId, Framebuffer> m_framebuffers{};
+
+private:
+    bool TryAcquireFramebufferLocked(VI::Layer& layer, Framebuffer& framebuffer);
+    CacheStatus CacheFramebufferLocked(VI::Layer& layer, LayerId layer_id);
+};
+
+} // namespace Service::Nvnflinger