From 60092ce849174e7541ea94a263d29ba32c8bb38f Mon Sep 17 00:00:00 2001
From: squidbus <175574877+squidbus@users.noreply.github.com>
Date: Sat, 5 Oct 2024 16:25:12 -0700
Subject: [PATCH] vulkan: Use view of null buffer for texel buffers if
 nullDescriptor not supported. (#1231)

---
 src/video_core/buffer_cache/buffer_cache.cpp          | 11 +++++++++++
 src/video_core/buffer_cache/buffer_cache.h            |  5 +++++
 .../renderer_vulkan/vk_compute_pipeline.cpp           |  4 +++-
 .../renderer_vulkan/vk_graphics_pipeline.cpp          |  4 +++-
 4 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/video_core/buffer_cache/buffer_cache.cpp b/src/video_core/buffer_cache/buffer_cache.cpp
index e806705d..c2993f3d 100644
--- a/src/video_core/buffer_cache/buffer_cache.cpp
+++ b/src/video_core/buffer_cache/buffer_cache.cpp
@@ -36,6 +36,17 @@ BufferCache::BufferCache(const Vulkan::Instance& instance_, Vulkan::Scheduler& s
     ASSERT(null_id.index == 0);
     const vk::Buffer& null_buffer = slot_buffers[null_id].buffer;
     Vulkan::SetObjectName(instance.GetDevice(), null_buffer, "Null Buffer");
+
+    const vk::BufferViewCreateInfo null_view_ci = {
+        .buffer = null_buffer,
+        .format = vk::Format::eR8Unorm,
+        .offset = 0,
+        .range = VK_WHOLE_SIZE,
+    };
+    const auto [null_view_result, null_view] = instance.GetDevice().createBufferView(null_view_ci);
+    ASSERT_MSG(null_view_result == vk::Result::eSuccess, "Failed to create null buffer view.");
+    null_buffer_view = null_view;
+    Vulkan::SetObjectName(instance.GetDevice(), null_buffer_view, "Null Buffer View");
 }
 
 BufferCache::~BufferCache() = default;
diff --git a/src/video_core/buffer_cache/buffer_cache.h b/src/video_core/buffer_cache/buffer_cache.h
index 8927083c..76309363 100644
--- a/src/video_core/buffer_cache/buffer_cache.h
+++ b/src/video_core/buffer_cache/buffer_cache.h
@@ -67,6 +67,10 @@ public:
         return slot_buffers[id];
     }
 
+    [[nodiscard]] vk::BufferView& NullBufferView() {
+        return null_buffer_view;
+    }
+
     /// Invalidates any buffer in the logical page range.
     void InvalidateMemory(VAddr device_addr, u64 size);
 
@@ -146,6 +150,7 @@ private:
     Buffer gds_buffer;
     std::mutex mutex;
     Common::SlotVector<Buffer> slot_buffers;
+    vk::BufferView null_buffer_view;
     MemoryTracker memory_tracker;
     PageTable page_table;
 };
diff --git a/src/video_core/renderer_vulkan/vk_compute_pipeline.cpp b/src/video_core/renderer_vulkan/vk_compute_pipeline.cpp
index cbce85cc..37a44dda 100644
--- a/src/video_core/renderer_vulkan/vk_compute_pipeline.cpp
+++ b/src/video_core/renderer_vulkan/vk_compute_pipeline.cpp
@@ -170,9 +170,11 @@ bool ComputePipeline::BindResources(VideoCore::BufferCache& buffer_cache,
         ++binding.buffer;
     }
 
+    const auto null_buffer_view =
+        instance.IsNullDescriptorSupported() ? VK_NULL_HANDLE : buffer_cache.NullBufferView();
     for (const auto& desc : info->texture_buffers) {
         const auto vsharp = desc.GetSharp(*info);
-        vk::BufferView& buffer_view = buffer_views.emplace_back(VK_NULL_HANDLE);
+        vk::BufferView& buffer_view = buffer_views.emplace_back(null_buffer_view);
         const u32 size = vsharp.GetSize();
         if (vsharp.GetDataFmt() != AmdGpu::DataFormat::FormatInvalid && size != 0) {
             const VAddr address = vsharp.base_address;
diff --git a/src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp b/src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp
index 9de551ba..cbc0fc5e 100644
--- a/src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp
+++ b/src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp
@@ -438,9 +438,11 @@ void GraphicsPipeline::BindResources(const Liverpool::Regs& regs,
             ++binding.buffer;
         }
 
+        const auto null_buffer_view =
+            instance.IsNullDescriptorSupported() ? VK_NULL_HANDLE : buffer_cache.NullBufferView();
         for (const auto& desc : stage->texture_buffers) {
             const auto vsharp = desc.GetSharp(*stage);
-            vk::BufferView& buffer_view = buffer_views.emplace_back(VK_NULL_HANDLE);
+            vk::BufferView& buffer_view = buffer_views.emplace_back(null_buffer_view);
             const u32 size = vsharp.GetSize();
             if (vsharp.GetDataFmt() != AmdGpu::DataFormat::FormatInvalid && size != 0) {
                 const VAddr address = vsharp.base_address;