nx2: leave unwritten sparse blocks without memory when they get zeros

Title 1 clears about 1 GB of its sparse regions at boot through the GPU
memory manager. Every block the clear touched got 4 MiB of guest memory,
which the clear itself then committed on the host, and counted as written,
so the texture cache gave the images over it device memory too. A block
nobody wrote reads zero already: when the part of a write that lands on
it is all zero, leave it as it is.

(cherry picked from commit 0d7ff63fd1a373cecff6ba91022c9027e801e53f)

1 files changed, 2 insertions, 2 deletions

diff --git a/src/video_core/memory_manager.cpp b/src/video_core/memory_manager.cpp
index a7d8aec382..ddfd2529fd 100644
--- a/src/video_core/memory_manager.cpp
+++ b/src/video_core/memory_manager.cpp
@@ -302,7 +302,7 @@ void MemoryManager::Write(GPUVAddr addr, T data) {
         return;
     }
     // A Switch 2 sparse block nobody wrote yet gets its memory now.
-    Tegra::Nx2BackSparseWrite(addr, sizeof(T));
+    Tegra::Nx2BackSparseWrite(addr, sizeof(T), &data);
     if (auto page_pointer{GetPointer(addr)}; page_pointer) {
         std::memcpy(page_pointer, &data, sizeof(T));
         return;
@@ -469,7 +469,7 @@ void MemoryManager::ReadBlockUnsafe(GPUVAddr gpu_src_addr, void* dest_buffer, co
 
 void MemoryManager::WriteBlockImpl(GPUVAddr gpu_dest_addr, const void* src_buffer, std::size_t size, [[maybe_unused]] VideoCommon::CacheType which, bool unsafe) {
     // Give Switch 2 sparse pages the write lands on their memory first (otherwise it is dropped).
-    Tegra::Nx2BackSparseWrite(gpu_dest_addr, size);
+    Tegra::Nx2BackSparseWrite(gpu_dest_addr, size, src_buffer);
     auto just_advance = [&]([[maybe_unused]] std::size_t page_index, [[maybe_unused]] std::size_t offset, std::size_t copy_amount) {
         src_buffer = static_cast<const u8*>(src_buffer) + copy_amount;
     };