From 22ce531e6f379f73bf23e634a37481e993968fb2 Mon Sep 17 00:00:00 2001
From: PixelyIon <pixelyion@protonmail.com>
Date: Sat, 22 Jan 2022 05:43:18 +0530
Subject: [PATCH] Force Memory Barrier at `VkRenderPass` Start

We depend on past commands to have completed execution in a renderpass, a subpass dependency on all graphics stages from `VK_SUBPASS_EXTERNAL` to subpass #0 is used to enforce this. Nvidia and Adreno proprietary drivers implicitly do this but Turnip or Mali drivers require this or they execute out of order.
---
 .../cpp/skyline/gpu/interconnect/command_nodes.cpp | 14 ++++++++++++++
 .../cpp/skyline/gpu/interconnect/command_nodes.h   |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.cpp b/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.cpp
index 5e2cd77c..b5066908 100644
--- a/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.cpp
+++ b/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.cpp
@@ -4,6 +4,20 @@
 #include "command_nodes.h"
 
 namespace skyline::gpu::interconnect::node {
+    RenderPassNode::RenderPassNode(vk::Rect2D renderArea) : subpassDependencies(
+        {
+            // We assume all past commands have been executed when this RP starts
+            vk::SubpassDependency{
+                .srcSubpass = VK_SUBPASS_EXTERNAL,
+                .dstSubpass = 0,
+                .srcStageMask = vk::PipelineStageFlagBits::eAllGraphics,
+                .dstStageMask = vk::PipelineStageFlagBits::eAllGraphics,
+                .srcAccessMask = vk::AccessFlagBits::eMemoryRead | vk::AccessFlagBits::eMemoryWrite,
+                .dstAccessMask = vk::AccessFlagBits::eMemoryRead | vk::AccessFlagBits::eMemoryWrite,
+            }
+        }
+    ), storage(std::make_shared<Storage>()), renderArea(renderArea) {}
+
     RenderPassNode::Storage::~Storage() {
         if (device) {
             if (framebuffer)
diff --git a/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.h b/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.h
index 95da0c00..75061594 100644
--- a/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.h
+++ b/app/src/main/cpp/skyline/gpu/interconnect/command_nodes.h
@@ -64,7 +64,7 @@ namespace skyline::gpu::interconnect::node {
         vk::Rect2D renderArea;
         std::vector<vk::ClearValue> clearValues;
 
-        RenderPassNode(vk::Rect2D renderArea) : storage(std::make_shared<Storage>()), renderArea(renderArea) {}
+        RenderPassNode(vk::Rect2D renderArea);
 
         /**
          * @note Any preservation of attachments from previous subpasses is automatically handled by this