Texture Cache: Implement async texture downloads.

src/video_core/renderer_opengl/gl_texture_cache.h

@@ -354,6 +354,7 @@ struct TextureCacheParams {
     static constexpr bool FRAMEBUFFER_BLITS = true;
     static constexpr bool HAS_EMULATED_COPIES = true;
     static constexpr bool HAS_DEVICE_MEMORY_INFO = true;
+    static constexpr bool IMPLEMENTS_ASYNC_DOWNLOADS = false;
 
     using Runtime = OpenGL::TextureCacheRuntime;
     using Image = OpenGL::Image;
@@ -361,6 +362,7 @@ struct TextureCacheParams {
     using ImageView = OpenGL::ImageView;
     using Sampler = OpenGL::Sampler;
     using Framebuffer = OpenGL::Framebuffer;
+    using AsyncBuffer = u32;
 };
 
 using TextureCache = VideoCommon::TextureCache<TextureCacheParams>;

src/video_core/renderer_vulkan/vk_texture_cache.cpp

@@ -812,8 +812,12 @@ StagingBufferRef TextureCacheRuntime::UploadStagingBuffer(size_t size) {
     return staging_buffer_pool.Request(size, MemoryUsage::Upload);
 }
 
-StagingBufferRef TextureCacheRuntime::DownloadStagingBuffer(size_t size) {
-    return staging_buffer_pool.Request(size, MemoryUsage::Download);
+StagingBufferRef TextureCacheRuntime::DownloadStagingBuffer(size_t size, bool deferred) {
+    return staging_buffer_pool.Request(size, MemoryUsage::Download, deferred);
+}
+
+void TextureCacheRuntime::FreeDeferredStagingBuffer(StagingBufferRef& ref) {
+    staging_buffer_pool.FreeDeferred(ref);
 }
 
 bool TextureCacheRuntime::ShouldReinterpret(Image& dst, Image& src) {

src/video_core/renderer_vulkan/vk_texture_cache.h

@@ -51,7 +51,9 @@ public:
 
     StagingBufferRef UploadStagingBuffer(size_t size);
 
-    StagingBufferRef DownloadStagingBuffer(size_t size);
+    StagingBufferRef DownloadStagingBuffer(size_t size, bool deferred = false);
+
+    void FreeDeferredStagingBuffer(StagingBufferRef& ref);
 
     void TickFrame();
 
@@ -347,6 +349,7 @@ struct TextureCacheParams {
     static constexpr bool FRAMEBUFFER_BLITS = false;
     static constexpr bool HAS_EMULATED_COPIES = false;
     static constexpr bool HAS_DEVICE_MEMORY_INFO = true;
+    static constexpr bool IMPLEMENTS_ASYNC_DOWNLOADS = true;
 
     using Runtime = Vulkan::TextureCacheRuntime;
     using Image = Vulkan::Image;
@@ -354,6 +357,7 @@ struct TextureCacheParams {
     using ImageView = Vulkan::ImageView;
     using Sampler = Vulkan::Sampler;
     using Framebuffer = Vulkan::Framebuffer;
+    using AsyncBuffer = Vulkan::StagingBufferRef;
 };
 
 using TextureCache = VideoCommon::TextureCache<TextureCacheParams>;

src/video_core/texture_cache/texture_cache.h

@@ -646,7 +646,28 @@ bool TextureCache<P>::ShouldWaitAsyncFlushes() const noexcept {
 template <class P>
 void TextureCache<P>::CommitAsyncFlushes() {
     // This is intentionally passing the value by copy
-    committed_downloads.push(uncommitted_downloads);
+    if constexpr (IMPLEMENTS_ASYNC_DOWNLOADS) {
+        const std::span<const ImageId> download_ids = uncommitted_downloads;
+        if (download_ids.empty()) {
+            committed_downloads.emplace_back(std::move(uncommitted_downloads));
+            uncommitted_downloads.clear();
+            async_buffers.emplace_back(std::optional<AsyncBuffer>{});
+            return;
+        }
+        size_t total_size_bytes = 0;
+        for (const ImageId image_id : download_ids) {
+            total_size_bytes += slot_images[image_id].unswizzled_size_bytes;
+        }
+        auto download_map = runtime.DownloadStagingBuffer(total_size_bytes, true);
+        for (const ImageId image_id : download_ids) {
+            Image& image = slot_images[image_id];
+            const auto copies = FullDownloadCopies(image.info);
+            image.DownloadMemory(download_map, copies);
+            download_map.offset += Common::AlignUp(image.unswizzled_size_bytes, 64);
+        }
+        async_buffers.emplace_back(download_map);
+    }
+    committed_downloads.emplace_back(std::move(uncommitted_downloads));
     uncommitted_downloads.clear();
 }
 
@@ -655,9 +676,30 @@ void TextureCache<P>::PopAsyncFlushes() {
     if (committed_downloads.empty()) {
         return;
     }
+    if constexpr (IMPLEMENTS_ASYNC_DOWNLOADS) {
         const std::span<const ImageId> download_ids = committed_downloads.front();
         if (download_ids.empty()) {
-        committed_downloads.pop();
+            committed_downloads.pop_front();
+            async_buffers.pop_front();
+            return;
+        }
+        auto download_map = *async_buffers.front();
+        std::span<u8> download_span = download_map.mapped_span;
+        for (size_t i = download_ids.size(); i > 0; i--) {
+            const ImageBase& image = slot_images[download_ids[i - 1]];
+            const auto copies = FullDownloadCopies(image.info);
+            download_map.offset -= Common::AlignUp(image.unswizzled_size_bytes, 64);
+            std::span<u8> download_span_alt = download_span.subspan(download_map.offset);
+            SwizzleImage(*gpu_memory, image.gpu_addr, image.info, copies, download_span_alt,
+                         swizzle_data_buffer);
+        }
+        runtime.FreeDeferredStagingBuffer(download_map);
+        committed_downloads.pop_front();
+        async_buffers.pop_front();
+    } else {
+        const std::span<const ImageId> download_ids = committed_downloads.front();
+        if (download_ids.empty()) {
+            committed_downloads.pop_front();
             return;
         }
         size_t total_size_bytes = 0;
@@ -674,7 +716,6 @@ void TextureCache<P>::PopAsyncFlushes() {
         }
         // Wait for downloads to finish
         runtime.Finish();
-
         download_map.offset = original_offset;
         std::span<u8> download_span = download_map.mapped_span;
         for (const ImageId image_id : download_ids) {
@@ -685,7 +726,8 @@ void TextureCache<P>::PopAsyncFlushes() {
             download_map.offset += image.unswizzled_size_bytes;
             download_span = download_span.subspan(image.unswizzled_size_bytes);
         }
-    committed_downloads.pop();
+        committed_downloads.pop_front();
+    }
 }
 
 template <class P>

src/video_core/texture_cache/texture_cache_base.h

@@ -92,6 +92,8 @@ class TextureCache : public VideoCommon::ChannelSetupCaches<TextureCacheChannelI
     static constexpr bool HAS_EMULATED_COPIES = P::HAS_EMULATED_COPIES;
     /// True when the API can provide info about the memory of the device.
     static constexpr bool HAS_DEVICE_MEMORY_INFO = P::HAS_DEVICE_MEMORY_INFO;
+    /// True when the API can do asynchronous texture downloads.
+    static constexpr bool IMPLEMENTS_ASYNC_DOWNLOADS = P::IMPLEMENTS_ASYNC_DOWNLOADS;
 
     static constexpr size_t UNSET_CHANNEL{std::numeric_limits<size_t>::max()};
 
@@ -106,6 +108,7 @@ class TextureCache : public VideoCommon::ChannelSetupCaches<TextureCacheChannelI
     using ImageView = typename P::ImageView;
     using Sampler = typename P::Sampler;
     using Framebuffer = typename P::Framebuffer;
+    using AsyncBuffer = typename P::AsyncBuffer;
 
     struct BlitImages {
         ImageId dst_id;
@@ -403,7 +406,8 @@ private:
 
     // TODO: This data structure is not optimal and it should be reworked
     std::vector<ImageId> uncommitted_downloads;
-    std::queue<std::vector<ImageId>> committed_downloads;
+    std::deque<std::vector<ImageId>> committed_downloads;
+    std::deque<std::optional<AsyncBuffer>> async_buffers;
 
     struct LRUItemParams {
         using ObjectType = ImageId;