From c4c52fc4b65badbc91a2971d8557b95ff306186e Mon Sep 17 00:00:00 2001
From: Dzmitry Malyshau <dmalyshau@mozilla.com>
Date: Wed, 8 Dec 2021 15:54:26 +0000
Subject: [PATCH] WIP: Bug 1622846 - Support WebGPU adapter isFallbackAdapter
 r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D133208
---
 dom/webgpu/Adapter.cpp           | 3 +--
 dom/webgpu/Adapter.h             | 4 ++--
 dom/webgpu/ipc/WebGPUParent.cpp  | 1 +
 dom/webgpu/ipc/WebGPUSerialize.h | 2 +-
 dom/webidl/WebGPU.webidl         | 3 ++-
 5 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/dom/webgpu/Adapter.cpp b/dom/webgpu/Adapter.cpp
index 29f7e5fa1f44..6a3653fb0caa 100644
--- a/dom/webgpu/Adapter.cpp
+++ b/dom/webgpu/Adapter.cpp
@@ -26,7 +26,7 @@ Adapter::Adapter(Instance* const aParent,
       mId(aInfo.id),
       mFeatures(new AdapterFeatures(this)),
       mLimits(new SupportedLimits(this, aInfo.limits)),
-      mIsSoftware(aInfo.ty == ffi::WGPUDeviceType_Cpu) {}
+      mIsFallbackAdapter(aInfo.ty == ffi::WGPUDeviceType_Cpu) {}
 
 Adapter::~Adapter() { Cleanup(); }
 
@@ -39,7 +39,6 @@ void Adapter::Cleanup() {
 
 const RefPtr<AdapterFeatures>& Adapter::Features() const { return mFeatures; }
 const RefPtr<SupportedLimits>& Adapter::Limits() const { return mLimits; }
-bool Adapter::IsSoftware() const { return mIsSoftware; }
 
 already_AddRefed<dom::Promise> Adapter::RequestDevice(
     const dom::GPUDeviceDescriptor& aDesc, ErrorResult& aRv) {
diff --git a/dom/webgpu/Adapter.h b/dom/webgpu/Adapter.h
index 8cee1d451e64..bcd14d79f9c2 100644
--- a/dom/webgpu/Adapter.h
+++ b/dom/webgpu/Adapter.h
@@ -47,14 +47,14 @@ class Adapter final : public ObjectBase, public ChildOf<Instance> {
   // to unlink them in CC unlink.
   RefPtr<AdapterFeatures> mFeatures;
   RefPtr<SupportedLimits> mLimits;
-  const bool mIsSoftware = false;
+  const bool mIsFallbackAdapter = false;
 
  public:
   Adapter(Instance* const aParent, const ffi::WGPUAdapterInformation& aInfo);
   void GetName(nsString& out) const { out = mName; }
   const RefPtr<AdapterFeatures>& Features() const;
   const RefPtr<SupportedLimits>& Limits() const;
-  bool IsSoftware() const;
+  bool IsFallbackAdapter() const { return mIsFallbackAdapter; }
 
   already_AddRefed<dom::Promise> RequestDevice(
       const dom::GPUDeviceDescriptor& aDesc, ErrorResult& aRv);
diff --git a/dom/webgpu/ipc/WebGPUParent.cpp b/dom/webgpu/ipc/WebGPUParent.cpp
index 4aae3d14d8fc..8327b4ad2533 100644
--- a/dom/webgpu/ipc/WebGPUParent.cpp
+++ b/dom/webgpu/ipc/WebGPUParent.cpp
@@ -235,6 +235,7 @@ ipc::IPCResult WebGPUParent::RecvInstanceRequestAdapter(
     options.power_preference = static_cast<ffi::WGPUPowerPreference>(
         aOptions.mPowerPreference.Value());
   }
+  options.force_fallback_adapter = aOptions.mForceFallbackAdapter;
   // TODO: make available backends configurable by prefs
 
   ErrorBuffer error;
diff --git a/dom/webgpu/ipc/WebGPUSerialize.h b/dom/webgpu/ipc/WebGPUSerialize.h
index 4eff8e43f1f8..18ed6f885369 100644
--- a/dom/webgpu/ipc/WebGPUSerialize.h
+++ b/dom/webgpu/ipc/WebGPUSerialize.h
@@ -31,7 +31,7 @@ DEFINE_IPC_SERIALIZER_FFI_ENUM(mozilla::webgpu::ffi::WGPUHostMap);
 DEFINE_IPC_SERIALIZER_WITHOUT_FIELDS(mozilla::dom::GPUCommandBufferDescriptor);
 
 DEFINE_IPC_SERIALIZER_WITH_FIELDS(mozilla::dom::GPURequestAdapterOptions,
-                                  mPowerPreference);
+                                  mPowerPreference, mForceFallbackAdapter);
 
 DEFINE_IPC_SERIALIZER_WITH_FIELDS(mozilla::webgpu::ScopedError, operationError,
                                   validationMessage);
diff --git a/dom/webidl/WebGPU.webidl b/dom/webidl/WebGPU.webidl
index 094a454af348..1bb84cfbfdf8 100644
--- a/dom/webidl/WebGPU.webidl
+++ b/dom/webidl/WebGPU.webidl
@@ -82,6 +82,7 @@ enum GPUPowerPreference {
 
 dictionary GPURequestAdapterOptions {
     GPUPowerPreference powerPreference;
+    boolean forceFallbackAdapter = false;
 };
 
 [Pref="dom.webgpu.enabled",
@@ -132,7 +133,7 @@ interface GPUAdapter {
     readonly attribute DOMString name;
     [SameObject] readonly attribute GPUAdapterFeatures features;
     [SameObject] readonly attribute GPUSupportedLimits limits;
-    readonly attribute boolean isSoftware;
+    readonly attribute boolean isFallbackAdapter;
 
     [NewObject]
     Promise<GPUDevice> requestDevice(optional GPUDeviceDescriptor descriptor = {});