Disable Render Buffer Compression on external displays.

When Getting format modifiers, exclude I915_FORMAT_MOD_Y*_TILED_CCS
(Intel color control surface (CCS) for render compression) if it's not
an internal display.
This solves the bandwidth issue when driving more than 1 4K monitor with
rbc enabled.

BUG=996011,996036,994341,979736
TEST=External display doesn't pick I915...CSS modifier

Change-Id: I9d7aa06f5f9331d232a3cbd7e74bd41771bc4030
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1912460
Commit-Queue: Mark Yacoub <markyacoub@google.com>
Reviewed-by: Michael Spang <spang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715332}

ui/ozone/platform/drm/common/drm_util.cc

@@ -108,28 +108,6 @@ float GetRefreshRate(const drmModeModeInfo& mode) {
   return (clock * 1000.0f) / (htotal * vtotal);
 }
 
-display::DisplayConnectionType GetDisplayType(drmModeConnector* connector) {
-  switch (connector->connector_type) {
-    case DRM_MODE_CONNECTOR_VGA:
-      return display::DISPLAY_CONNECTION_TYPE_VGA;
-    case DRM_MODE_CONNECTOR_DVII:
-    case DRM_MODE_CONNECTOR_DVID:
-    case DRM_MODE_CONNECTOR_DVIA:
-      return display::DISPLAY_CONNECTION_TYPE_DVI;
-    case DRM_MODE_CONNECTOR_LVDS:
-    case DRM_MODE_CONNECTOR_eDP:
-    case DRM_MODE_CONNECTOR_DSI:
-      return display::DISPLAY_CONNECTION_TYPE_INTERNAL;
-    case DRM_MODE_CONNECTOR_DisplayPort:
-      return display::DISPLAY_CONNECTION_TYPE_DISPLAYPORT;
-    case DRM_MODE_CONNECTOR_HDMIA:
-    case DRM_MODE_CONNECTOR_HDMIB:
-      return display::DISPLAY_CONNECTION_TYPE_HDMI;
-    default:
-      return display::DISPLAY_CONNECTION_TYPE_UNKNOWN;
-  }
-}
-
 int GetDrmProperty(int fd,
                    drmModeConnector* connector,
                    const std::string& name,
@@ -425,6 +403,29 @@ display::DisplaySnapshot::DisplayModeList ExtractDisplayModes(
   return modes;
 }
 
+display::DisplayConnectionType GetDisplayType(
+    const drmModeConnector* connector) {
+  switch (connector->connector_type) {
+    case DRM_MODE_CONNECTOR_VGA:
+      return display::DISPLAY_CONNECTION_TYPE_VGA;
+    case DRM_MODE_CONNECTOR_DVII:
+    case DRM_MODE_CONNECTOR_DVID:
+    case DRM_MODE_CONNECTOR_DVIA:
+      return display::DISPLAY_CONNECTION_TYPE_DVI;
+    case DRM_MODE_CONNECTOR_LVDS:
+    case DRM_MODE_CONNECTOR_eDP:
+    case DRM_MODE_CONNECTOR_DSI:
+      return display::DISPLAY_CONNECTION_TYPE_INTERNAL;
+    case DRM_MODE_CONNECTOR_DisplayPort:
+      return display::DISPLAY_CONNECTION_TYPE_DISPLAYPORT;
+    case DRM_MODE_CONNECTOR_HDMIA:
+    case DRM_MODE_CONNECTOR_HDMIB:
+      return display::DISPLAY_CONNECTION_TYPE_HDMI;
+    default:
+      return display::DISPLAY_CONNECTION_TYPE_UNKNOWN;
+  }
+}
+
 std::unique_ptr<display::DisplaySnapshot> CreateDisplaySnapshot(
     HardwareDisplayControllerInfo* info,
     int fd,

ui/ozone/platform/drm/common/drm_util.h

@@ -71,6 +71,9 @@ display::DisplaySnapshot::DisplayModeList ExtractDisplayModes(
     const display::DisplayMode** out_current_mode,
     const display::DisplayMode** out_native_mode);
 
+display::DisplayConnectionType GetDisplayType(
+    const drmModeConnector* connector);
+
 // |info| provides the DRM information related to the display, |fd| is the
 // connection to the DRM device.
 std::unique_ptr<display::DisplaySnapshot> CreateDisplaySnapshot(

ui/ozone/platform/drm/gpu/crtc_controller.cc

@@ -8,7 +8,9 @@
 
 #include "base/logging.h"
 #include "base/time/time.h"
+#include "ui/display/types/display_constants.h"
 #include "ui/gfx/presentation_feedback.h"
+#include "ui/ozone/platform/drm/common/drm_util.h"
 #include "ui/ozone/platform/drm/gpu/drm_device.h"
 #include "ui/ozone/platform/drm/gpu/drm_dumb_buffer.h"
 #include "ui/ozone/platform/drm/gpu/drm_framebuffer.h"
@@ -22,7 +24,9 @@ CrtcController::CrtcController(const scoped_refptr<DrmDevice>& drm,
                                uint32_t connector)
     : drm_(drm),
       crtc_(crtc),
-      connector_(connector) {}
+      connector_(connector),
+      internal_diplay_only_modifiers_(
+          {I915_FORMAT_MOD_Y_TILED_CCS, I915_FORMAT_MOD_Yf_TILED_CCS}) {}
 
 CrtcController::~CrtcController() {
   if (!is_disabled_) {
@@ -96,7 +100,21 @@ bool CrtcController::AssignOverlayPlanes(HardwareDisplayPlaneList* plane_list,
 }
 
 std::vector<uint64_t> CrtcController::GetFormatModifiers(uint32_t format) {
-  return drm_->plane_manager()->GetFormatModifiers(crtc_, format);
+  std::vector<uint64_t> modifiers =
+      drm_->plane_manager()->GetFormatModifiers(crtc_, format);
+
+  display::DisplayConnectionType display_type =
+      ui::GetDisplayType(drm_->GetConnector(connector_).get());
+  // If this is an external display, remove the modifiers applicable to internal
+  // displays only.
+  if (display_type != display::DISPLAY_CONNECTION_TYPE_INTERNAL) {
+    for (auto modifier : internal_diplay_only_modifiers_) {
+      modifiers.erase(std::remove(modifiers.begin(), modifiers.end(), modifier),
+                      modifiers.end());
+    }
+  }
+
+  return modifiers;
 }
 
 void CrtcController::SetCursor(uint32_t handle, const gfx::Size& size) {

ui/ozone/platform/drm/gpu/crtc_controller.h

@@ -75,6 +75,8 @@ class CrtcController {
   // TODO(dnicoara) Add support for hardware mirroring (multiple connectors).
   const uint32_t connector_;
 
+  const std::vector<uint64_t> internal_diplay_only_modifiers_;
+
   drmModeModeInfo mode_ = {};
 
   scoped_refptr<DrmFramebuffer> modeset_framebuffer_;

ui/ozone/platform/drm/gpu/hardware_display_controller_unittest.cc

@@ -47,7 +47,7 @@ const gfx::SizeF kDefaultModeSizeF(1.0, 1.0);
 class HardwareDisplayControllerTest : public testing::Test {
  public:
   HardwareDisplayControllerTest() : page_flips_(0) {}
-  ~HardwareDisplayControllerTest() override {}
+  ~HardwareDisplayControllerTest() override = default;
 
   void SetUp() override;
   void TearDown() override;
@@ -147,8 +147,17 @@ void HardwareDisplayControllerTest::InitializeDrmDevice(bool use_atomic) {
             {/* .id = */ pair.first, /*.value = */ value});
       };
 
+      drm_format_modifier y_css = {.formats = 1UL,
+                                   .modifier = I915_FORMAT_MOD_Y_TILED_CCS};
+      drm_format_modifier yf_css = {.formats = 1UL,
+                                    .modifier = I915_FORMAT_MOD_Yf_TILED_CCS};
+      drm_format_modifier x = {.formats = 1UL,
+                               .modifier = I915_FORMAT_MOD_X_TILED};
+      drm_format_modifier linear = {.formats = 1UL,
+                                    .modifier = DRM_FORMAT_MOD_LINEAR};
       drm_->SetPropertyBlob(ui::MockDrmDevice::AllocateInFormatsBlob(
-          kInFormatsBlobPropId, {DRM_FORMAT_XRGB8888}, {}));
+          kInFormatsBlobPropId, {DRM_FORMAT_XRGB8888},
+          {y_css, yf_css, x, linear}));
 
       plane_properties.emplace_back(std::move(plane));
     }
@@ -198,6 +207,52 @@ TEST_F(HardwareDisplayControllerTest, CheckModesettingResult) {
   EXPECT_FALSE(plane.buffer->HasOneRef());
 }
 
+TEST_F(HardwareDisplayControllerTest, ModifiersWithConnectorType) {
+  ui::DrmOverlayPlane plane(CreateBuffer(), nullptr);
+
+  // With internal displays, all modifiers including compressed (css) should be
+  // there.
+  drm_->set_connector_type(DRM_MODE_CONNECTOR_eDP);
+
+  std::vector<uint64_t> internal_modifiers =
+      controller_->GetFormatModifiers(DRM_FORMAT_XRGB8888);
+  ASSERT_FALSE(internal_modifiers.empty());
+
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      I915_FORMAT_MOD_Y_TILED_CCS),
+            internal_modifiers.end());
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      I915_FORMAT_MOD_Yf_TILED_CCS),
+            internal_modifiers.end());
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      I915_FORMAT_MOD_X_TILED),
+            internal_modifiers.end());
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      DRM_FORMAT_MOD_LINEAR),
+            internal_modifiers.end());
+
+  // With external displays, *_CSS modifiers (2 of them) should not exist.
+  drm_->set_connector_type(DRM_MODE_CONNECTOR_DisplayPort);
+
+  std::vector<uint64_t> external_modifiers =
+      controller_->GetFormatModifiers(DRM_FORMAT_XRGB8888);
+  ASSERT_FALSE(external_modifiers.empty());
+  EXPECT_EQ(external_modifiers.size(), internal_modifiers.size() - 2);
+
+  EXPECT_EQ(std::find(external_modifiers.begin(), external_modifiers.end(),
+                      I915_FORMAT_MOD_Y_TILED_CCS),
+            external_modifiers.end());
+  EXPECT_EQ(std::find(external_modifiers.begin(), external_modifiers.end(),
+                      I915_FORMAT_MOD_Yf_TILED_CCS),
+            external_modifiers.end());
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      I915_FORMAT_MOD_X_TILED),
+            internal_modifiers.end());
+  EXPECT_NE(std::find(internal_modifiers.begin(), internal_modifiers.end(),
+                      DRM_FORMAT_MOD_LINEAR),
+            internal_modifiers.end());
+}
+
 TEST_F(HardwareDisplayControllerTest, CheckStateAfterPageFlip) {
   ui::DrmOverlayPlane plane1(CreateBuffer(), nullptr);
 

ui/ozone/platform/drm/gpu/mock_drm_device.cc

@@ -217,7 +217,11 @@ bool MockDrmDevice::DisableCrtc(uint32_t crtc_id) {
 }
 
 ScopedDrmConnectorPtr MockDrmDevice::GetConnector(uint32_t connector_id) {
-  return ScopedDrmConnectorPtr(DrmAllocator<drmModeConnector>());
+  ScopedDrmConnectorPtr connector =
+      ScopedDrmConnectorPtr(DrmAllocator<drmModeConnector>());
+  connector->connector_id = connector_id;
+  connector->connector_type = connector_type_;
+  return connector;
 }
 
 bool MockDrmDevice::AddFramebuffer2(uint32_t width,

ui/ozone/platform/drm/gpu/mock_drm_device.h

@@ -89,6 +89,8 @@ class MockDrmDevice : public DrmDevice {
     return it != crtc_cursor_map_.end() ? it->second : 0;
   }
 
+  void set_connector_type(uint32_t type) { connector_type_ = type; }
+
   void InitializeState(const std::vector<CrtcProperties>& crtc_properties,
                        const std::vector<PlaneProperties>& plane_properties,
                        const std::map<uint32_t, std::string>& property_names,
@@ -223,6 +225,8 @@ class MockDrmDevice : public DrmDevice {
 
   std::set<uint32_t> allocated_property_blobs_;
 
+  uint32_t connector_type_;
+
   DISALLOW_COPY_AND_ASSIGN(MockDrmDevice);
 };