From db6cc41b9db871ade06c6d14753af7efa1ca5f2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Thu, 22 Oct 2026 18:31:13 +0200
Subject: [PATCH 1/2] Vulkan: Ask for portability drivers on Mac

Through the Khronos loader (like the Vulkan SDK's, needed for the
validation layers), MoltenVK is only listed if the instance enables
VK_KHR_portability_enumeration. Without it, instance creation failed with
VK_ERROR_INCOMPATIBLE_DRIVER and we fell back to OpenGL. Loading MoltenVK
directly, as the app normally does, works as before.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
---
 Common/GPU/Vulkan/VulkanContext.cpp |  9 +++++++++
 Common/GPU/Vulkan/VulkanLoader.cpp  | 10 ++++++++++
 2 files changed, 19 insertions(+)

diff --git a/Common/GPU/Vulkan/VulkanContext.cpp b/Common/GPU/Vulkan/VulkanContext.cpp
index 08e7398961..8bcec8cb35 100644
--- a/Common/GPU/Vulkan/VulkanContext.cpp
+++ b/Common/GPU/Vulkan/VulkanContext.cpp
@@ -239,6 +239,15 @@ VkResult VulkanContext::CreateInstance(const CreateInfo &info) {
 
 #if PPSSPP_VK_STATIC
 	inst_info.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+#elif PPSSPP_PLATFORM(MAC)
+	// Through the Khronos loader (like the SDK's, for the validation layers), MoltenVK is only
+	// listed if we ask for portability drivers.
+	if (IsInstanceExtensionAvailable(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME)) {
+		instance_extensions_enabled_.push_back(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME);
+		inst_info.enabledExtensionCount = (uint32_t)instance_extensions_enabled_.size();
+		inst_info.ppEnabledExtensionNames = instance_extensions_enabled_.data();
+		inst_info.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+	}
 #endif
 
 #if SIMULATE_VULKAN_FAILURE == 2
diff --git a/Common/GPU/Vulkan/VulkanLoader.cpp b/Common/GPU/Vulkan/VulkanLoader.cpp
index 86ec0b6d9e..5733dae1fe 100644
--- a/Common/GPU/Vulkan/VulkanLoader.cpp
+++ b/Common/GPU/Vulkan/VulkanLoader.cpp
@@ -494,6 +494,7 @@ bool VulkanMayBeAvailable() {
 	std::vector<VkPhysicalDevice> devices;
 	bool anyGood = false;
 	const char *instanceExtensions[10]{};
+	bool portabilityFound = false;
 	VkInstance instance = VK_NULL_HANDLE;
 	VkResult res = VK_SUCCESS;
 	uint32_t physicalDeviceCount = 0;
@@ -544,6 +545,11 @@ bool VulkanMayBeAvailable() {
 			platformSurfaceExtensionFound = true;
 			// Note: Can't stop here - the enumeration order isn't specified anywhere, so VK_KHR_surface
 			// may well come after the platform one, and we need both.
+#if PPSSPP_PLATFORM(MAC)
+		} else if (!strcmp(iter.extensionName, VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME)) {
+			// See VulkanContext::CreateInstance.
+			portabilityFound = true;
+#endif
 		} else if (!strcmp(iter.extensionName, VK_KHR_SURFACE_EXTENSION_NAME)) {
 			instanceExtensions[ci.enabledExtensionCount++] = VK_KHR_SURFACE_EXTENSION_NAME;
 			surfaceExtensionFound = true;
@@ -576,6 +582,10 @@ bool VulkanMayBeAvailable() {
 	info.pEngineName = "VulkanCheckerEngine";
 	ci.pApplicationInfo = &info;
 	ci.flags = 0;
+	if (portabilityFound) {
+		instanceExtensions[ci.enabledExtensionCount++] = VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME;
+		ci.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+	}
 	INFO_LOG(Log::G3D, "VulkanMayBeAvailable: Calling vkCreateInstance");
 	res = localCreateInstance(&ci, nullptr, &instance);
 	if (res != VK_SUCCESS) {

From b46e386f12220e3fbfa3152d168fc07f79879832 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Thu, 22 Oct 2026 18:33:16 +0200
Subject: [PATCH 2/2] Vulkan: Enable the portability subset features MoltenVK
 has

We queried VkPhysicalDevicePortabilitySubsetFeaturesKHR but never enabled
it at device creation, so to the validation layers we were using image
view swizzles (and sampler LOD bias) without having them. Enable whatever
the device offers.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
---
 Common/GPU/Vulkan/VulkanContext.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Common/GPU/Vulkan/VulkanContext.cpp b/Common/GPU/Vulkan/VulkanContext.cpp
index 8bcec8cb35..827737b195 100644
--- a/Common/GPU/Vulkan/VulkanContext.cpp
+++ b/Common/GPU/Vulkan/VulkanContext.cpp
@@ -889,6 +889,13 @@ VkResult VulkanContext::CreateDevice(int physical_device, const std::vector<cons
 		deviceFeatures_.enabled.scalarBlockLayout.scalarBlockLayout = deviceFeatures_.available.scalarBlockLayout.scalarBlockLayout;
 	}
 
+	// What MoltenVK can do of what full Vulkan can (like image view swizzles). Using any of it needs it enabled.
+	deviceFeatures_.enabled.portabilitySubset = { VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_PORTABILITY_SUBSET_FEATURES_KHR };
+	if (extensionsLookup_.KHR_portability_subset) {
+		deviceFeatures_.enabled.portabilitySubset = deviceFeatures_.available.portabilitySubset;
+		deviceFeatures_.enabled.portabilitySubset.pNext = nullptr;
+	}
+
 	// deviceFeatures_.enabled.multiview.multiviewGeometryShader = deviceFeatures_.available.multiview.multiviewGeometryShader;
 
 	VkPhysicalDeviceFeatures2 features2{ VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FEATURES_2 };
@@ -920,6 +927,9 @@ VkResult VulkanContext::CreateDevice(int physical_device, const std::vector<cons
 		if (extensionsLookup_.KHR_present_mode_fifo_latest_ready) {
 			ChainStruct(features2, &deviceFeatures_.enabled.presentModeFifoProps);
 		}
+		if (extensionsLookup_.KHR_portability_subset) {
+			ChainStruct(features2, &deviceFeatures_.enabled.portabilitySubset);
+		}
 	} else {
 		device_info.pEnabledFeatures = &deviceFeatures_.enabled.standard;
 	}