From c2a6da64311c35670e7cbf4c8f1700263537fe7f Mon Sep 17 00:00:00 2001
From: PixelyIon <pixelyion@protonmail.com>
Date: Tue, 16 Nov 2021 16:12:30 +0530
Subject: [PATCH] Implement Maxwell3D Vertex Buffer Limit

Sets the end of VBOs based on the `vertexArrayLimits` register array which provides an IOVA to the end of the VBO.
---
 .../gpu/interconnect/graphics_context.h       | 21 ++++++++++++++-----
 .../skyline/soc/gm20b/engines/maxwell_3d.cpp  | 10 +++++++--
 .../skyline/soc/gm20b/engines/maxwell_3d.h    |  2 ++
 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h b/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
index 73ea4173..37ccb322 100644
--- a/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
+++ b/app/src/main/cpp/skyline/gpu/interconnect/graphics_context.h
@@ -766,7 +766,10 @@ namespace skyline::gpu::interconnect {
 
         /* Vertex Buffers */
       private:
-        std::array<IOVA, maxwell3d::VertexBufferCount> vertexBindingIovas{};
+        struct VertexBuffer {
+            IOVA start{}, end{}; //!< IOVAs covering a contiguous region in GPU AS with the vertex buffer
+        };
+        std::array<VertexBuffer, maxwell3d::VertexBufferCount> vertexBuffers{};
         std::array<vk::VertexInputBindingDescription, maxwell3d::VertexBufferCount> vertexBindings{};
         std::array<vk::VertexInputBindingDivisorDescriptionEXT, maxwell3d::VertexBufferCount> vertexBindingDivisors{};
         vk::StructureChain<vk::PipelineVertexInputStateCreateInfo, vk::PipelineVertexInputDivisorStateCreateInfoEXT> vertexState{
@@ -788,12 +791,20 @@ namespace skyline::gpu::interconnect {
             vertexBindings[index].inputRate = isPerInstance ? vk::VertexInputRate::eInstance : vk::VertexInputRate::eVertex;
         }
 
-        void SetVertexBufferIovaHigh(u32 index, u32 high) {
-            vertexBindingIovas[index].high = high;
+        void SetVertexBufferStartIovaHigh(u32 index, u32 high) {
+            vertexBuffers[index].start.high = high;
         }
 
-        void SetVertexBufferIovaLow(u32 index, u32 low) {
-            vertexBindingIovas[index].low = low;
+        void SetVertexBufferStartIovaLow(u32 index, u32 low) {
+            vertexBuffers[index].start.low = low;
+        }
+
+        void SetVertexBufferEndIovaHigh(u32 index, u32 high) {
+            vertexBuffers[index].end.high = high;
+        }
+
+        void SetVertexBufferEndIovaLow(u32 index, u32 low) {
+            vertexBuffers[index].end.low = low;
         }
 
         void SetVertexBufferDivisor(u32 index, u32 divisor) {
diff --git a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
index 7c950fe7..270dca15 100644
--- a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
+++ b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.cpp
@@ -329,16 +329,22 @@ namespace skyline::soc::gm20b::engine::maxwell3d {
                     context.SetVertexBufferStride(index, config.stride);                   \
                 })                                                                         \
                 MAXWELL3D_ARRAY_STRUCT_STRUCT_CASE(vertexBuffers, index, iova, high, {     \
-                    context.SetVertexBufferIovaHigh(index, high);                          \
+                    context.SetVertexBufferStartIovaHigh(index, high);                     \
                 })                                                                         \
                 MAXWELL3D_ARRAY_STRUCT_STRUCT_CASE(vertexBuffers, index, iova, low, {      \
-                    context.SetVertexBufferIovaLow(index, low);                            \
+                    context.SetVertexBufferStartIovaLow(index, low);                       \
                 })                                                                         \
                 MAXWELL3D_ARRAY_STRUCT_CASE(vertexBuffers, index, divisor, {               \
                     context.SetVertexBufferDivisor(index, divisor);                        \
                 })                                                                         \
                 MAXWELL3D_ARRAY_CASE(isVertexInputRatePerInstance, index, {                \
                     context.SetVertexBufferInputRate(index, isVertexInputRatePerInstance); \
+                })                                                                         \
+                MAXWELL3D_ARRAY_STRUCT_CASE(vertexBufferLimits, index, high, {             \
+                    context.SetVertexBufferEndIovaHigh(index, high);                       \
+                })                                                                         \
+                MAXWELL3D_ARRAY_STRUCT_CASE(vertexBufferLimits, index, low, {              \
+                    context.SetVertexBufferEndIovaLow(index, low);                         \
                 })
 
                 BOOST_PP_REPEAT(16, VERTEX_BUFFER_CALLBACKS, 0)
diff --git a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.h b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.h
index 3b15399c..42f41f88 100644
--- a/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.h
+++ b/app/src/main/cpp/skyline/soc/gm20b/engines/maxwell_3d.h
@@ -258,6 +258,8 @@ namespace skyline::soc::gm20b::engine::maxwell3d {
             };
             Register<0x780, std::array<IndependentBlend, type::RenderTargetCount>> independentBlend;
 
+            Register<0x7C0, std::array<type::Address, type::VertexBufferCount>> vertexBufferLimits; //!< A per-VBO IOVA denoting the end of the vertex buffer
+
             Register<0x800, std::array<type::SetProgramInfo, type::StageCount>> setProgram;
 
             Register<0x8C0, u32[0x20]> firmwareCall;