GPU: Partially implemented the Fermi2D surface copy operation.

The hardware allows for some rather complicated operations to be performed on the data during the copy, this is not implemented.
Only same-format same-size raw copies are implemented for now.

src/video_core/engines/fermi_2d.cpp

@@ -2,7 +2,9 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include "core/memory.h"
 #include "video_core/engines/fermi_2d.h"
+#include "video_core/textures/decoders.h"
 
 namespace Tegra {
 namespace Engines {
@@ -12,6 +14,58 @@ Fermi2D::Fermi2D(MemoryManager& memory_manager) : memory_manager(memory_manager)
 void Fermi2D::WriteReg(u32 method, u32 value) {
     ASSERT_MSG(method < Regs::NUM_REGS,
                "Invalid Fermi2D register, increase the size of the Regs structure");
+
+    regs.reg_array[method] = value;
+
+    switch (method) {
+    case FERMI2D_REG_INDEX(trigger): {
+        HandleSurfaceCopy();
+        break;
+    }
+    }
+}
+
+void Fermi2D::HandleSurfaceCopy() {
+    NGLOG_WARNING(HW_GPU, "Requested a surface copy with operation {}",
+                  static_cast<u32>(regs.operation));
+
+    const GPUVAddr source = regs.src.Address();
+    const GPUVAddr dest = regs.dst.Address();
+
+    // TODO(Subv): Only same-format and same-size copies are allowed for now.
+    ASSERT(regs.src.format == regs.dst.format);
+    ASSERT(regs.src.width * regs.src.height == regs.dst.width * regs.dst.height);
+
+    // TODO(Subv): Only raw copies are implemented.
+    ASSERT(regs.operation == Regs::Operation::SrcCopy);
+
+    const VAddr source_cpu = *memory_manager.GpuToCpuAddress(source);
+    const VAddr dest_cpu = *memory_manager.GpuToCpuAddress(dest);
+
+    u32 src_bytes_per_pixel = RenderTargetBytesPerPixel(regs.src.format);
+    u32 dst_bytes_per_pixel = RenderTargetBytesPerPixel(regs.dst.format);
+
+    if (regs.src.linear == regs.dst.linear) {
+        // If the input layout and the output layout are the same, just perform a raw copy.
+        Memory::CopyBlock(dest_cpu, source_cpu,
+                          src_bytes_per_pixel * regs.dst.width * regs.dst.height);
+        return;
+    }
+
+    u8* src_buffer = Memory::GetPointer(source_cpu);
+    u8* dst_buffer = Memory::GetPointer(dest_cpu);
+
+    if (!regs.src.linear && regs.dst.linear) {
+        // If the input is tiled and the output is linear, deswizzle the input and copy it over.
+        Texture::CopySwizzledData(regs.src.width, regs.src.height, src_bytes_per_pixel,
+                                  dst_bytes_per_pixel, src_buffer, dst_buffer, true,
+                                  regs.src.block_height);
+    } else {
+        // If the input is linear and the output is tiled, swizzle the input and copy it over.
+        Texture::CopySwizzledData(regs.src.width, regs.src.height, src_bytes_per_pixel,
+                                  dst_bytes_per_pixel, dst_buffer, src_buffer, false,
+                                  regs.dst.block_height);
+    }
 }
 
 } // namespace Engines

src/video_core/engines/fermi_2d.h

@@ -88,6 +88,11 @@ public:
     } regs{};
 
     MemoryManager& memory_manager;
+
+private:
+    /// Performs the copy from the source surface to the destination surface as configured in the
+    /// registers.
+    void HandleSurfaceCopy();
 };
 
 #define ASSERT_REG_POSITION(field_name, position)                                                  \