hardware_composer.h revision 2251d822dac2a96aad4184a6fdc2690f0a58af7c
1#ifndef ANDROID_DVR_SERVICES_DISPLAYD_HARDWARE_COMPOSER_H_ 2#define ANDROID_DVR_SERVICES_DISPLAYD_HARDWARE_COMPOSER_H_ 3 4#include <ui/GraphicBuffer.h> 5#include "DisplayHardware/ComposerHal.h" 6#include "hwc_types.h" 7 8#include <hardware/gralloc.h> 9#include <log/log.h> 10 11#include <array> 12#include <condition_variable> 13#include <memory> 14#include <mutex> 15#include <thread> 16#include <tuple> 17#include <vector> 18 19#include <dvr/pose_client.h> 20#include <pdx/file_handle.h> 21#include <pdx/rpc/variant.h> 22#include <private/dvr/buffer_hub_client.h> 23#include <private/dvr/frame_time_history.h> 24#include <private/dvr/sync_util.h> 25 26#include "acquired_buffer.h" 27#include "display_surface.h" 28 29// Hardware composer HAL doesn't define HWC_TRANSFORM_NONE as of this writing. 30#ifndef HWC_TRANSFORM_NONE 31#define HWC_TRANSFORM_NONE static_cast<hwc_transform_t>(0) 32#endif 33 34namespace android { 35namespace dvr { 36 37// Basic display metrics for physical displays. Dimensions and densities are 38// relative to the physical display orientation, which may be different from the 39// logical display orientation exposed to applications. 40struct HWCDisplayMetrics { 41 int width; 42 int height; 43 struct { 44 int x; 45 int y; 46 } dpi; 47 int vsync_period_ns; 48}; 49 50// Layer represents the connection between a hardware composer layer and the 51// source supplying buffers for the layer's contents. 52class Layer { 53 public: 54 Layer() {} 55 56 // Sets up the global state used by all Layer instances. This must be called 57 // before using any Layer methods. 58 static void InitializeGlobals(Hwc2::Composer* hwc2_hidl, 59 const HWCDisplayMetrics* metrics); 60 61 // Releases any shared pointers and fence handles held by this instance. 62 void Reset(); 63 64 // Sets up the layer to use a display surface as its content source. The Layer 65 // automatically handles ACQUIRE/RELEASE phases for the surface's buffer train 66 // every frame. 67 // 68 // |blending| receives HWC_BLENDING_* values. 69 // |transform| receives HWC_TRANSFORM_* values. 70 // |composition_type| receives either HWC_FRAMEBUFFER for most layers or 71 // HWC_FRAMEBUFFER_TARGET (unless you know what you are doing). 72 // |index| is the index of this surface in the DirectDisplaySurface array. 73 void Setup(const std::shared_ptr<DirectDisplaySurface>& surface, 74 HWC::BlendMode blending, HWC::Transform transform, 75 HWC::Composition composition_type, size_t z_roder); 76 77 // Sets up the layer to use a direct buffer as its content source. No special 78 // handling of the buffer is performed; responsibility for updating or 79 // changing the buffer each frame is on the caller. 80 // 81 // |blending| receives HWC_BLENDING_* values. 82 // |transform| receives HWC_TRANSFORM_* values. 83 // |composition_type| receives either HWC_FRAMEBUFFER for most layers or 84 // HWC_FRAMEBUFFER_TARGET (unless you know what you are doing). 85 void Setup(const std::shared_ptr<IonBuffer>& buffer, HWC::BlendMode blending, 86 HWC::Transform transform, HWC::Composition composition_type, 87 size_t z_order); 88 89 // Layers that use a direct IonBuffer should call this each frame to update 90 // which buffer will be used for the next PostLayers. 91 void UpdateBuffer(const std::shared_ptr<IonBuffer>& buffer); 92 93 // Sets up the hardware composer layer for the next frame. When the layer is 94 // associated with a display surface, this method automatically ACQUIRES a new 95 // buffer if one is available. 96 void Prepare(); 97 98 // After calling prepare, if this frame is to be dropped instead of passing 99 // along to the HWC, call Drop to close the contained fence(s). 100 void Drop(); 101 102 // Performs fence bookkeeping after the frame has been posted to hardware 103 // composer. 104 void Finish(int release_fence_fd); 105 106 // Sets the blending for the layer. |blending| receives HWC_BLENDING_* values. 107 void SetBlending(HWC::BlendMode blending); 108 109 // Sets the z-order of this layer 110 void SetZOrder(size_t z_order); 111 112 // Gets the current IonBuffer associated with this layer. Ownership of the 113 // buffer DOES NOT pass to the caller and the pointer is not guaranteed to 114 // remain valid across calls to Layer::Setup(), Layer::Prepare(), or 115 // Layer::Reset(). YOU HAVE BEEN WARNED. 116 IonBuffer* GetBuffer(); 117 118 HWC::Composition GetCompositionType() const { return composition_type_; } 119 HWC::Layer GetLayerHandle() const { return hardware_composer_layer_; } 120 bool IsLayerSetup() const { return !source_.empty(); } 121 122 // Applies all of the settings to this layer using the hwc functions 123 void UpdateLayerSettings(); 124 125 int GetSurfaceId() const { 126 int surface_id = -1; 127 pdx::rpc::IfAnyOf<SourceSurface>::Call( 128 &source_, [&surface_id](const SourceSurface& surface_source) { 129 surface_id = surface_source.surface->surface_id(); 130 }); 131 return surface_id; 132 } 133 134 private: 135 void CommonLayerSetup(); 136 137 static Hwc2::Composer* hwc2_hidl_; 138 static const HWCDisplayMetrics* display_metrics_; 139 140 // The hardware composer layer and metrics to use during the prepare cycle. 141 hwc2_layer_t hardware_composer_layer_ = 0; 142 143 // Layer properties used to setup the hardware composer layer during the 144 // Prepare phase. 145 size_t z_order_ = 0; 146 HWC::BlendMode blending_ = HWC::BlendMode::None; 147 HWC::Transform transform_ = HWC::Transform::None; 148 HWC::Composition composition_type_ = HWC::Composition::Invalid; 149 HWC::Composition target_composition_type_ = HWC::Composition::Device; 150 151 // State when the layer is connected to a surface. Provides the same interface 152 // as SourceBuffer to simplify internal use by Layer. 153 struct SourceSurface { 154 std::shared_ptr<DirectDisplaySurface> surface; 155 AcquiredBuffer acquired_buffer; 156 pdx::LocalHandle release_fence; 157 158 SourceSurface(const std::shared_ptr<DirectDisplaySurface>& surface) 159 : surface(surface) {} 160 161 // Attempts to acquire a new buffer from the surface and return a tuple with 162 // width, height, buffer handle, and fence. If a new buffer is not available 163 // the previous buffer is returned or an empty value if no buffer has ever 164 // been posted. When a new buffer is acquired the previous buffer's release 165 // fence is passed out automatically. 166 std::tuple<int, int, sp<GraphicBuffer>, pdx::LocalHandle> Acquire() { 167 if (surface->IsBufferAvailable()) { 168 acquired_buffer.Release(std::move(release_fence)); 169 acquired_buffer = surface->AcquireCurrentBuffer(); 170 ATRACE_ASYNC_END("BufferPost", acquired_buffer.buffer()->id()); 171 } 172 if (!acquired_buffer.IsEmpty()) { 173 return std::make_tuple(acquired_buffer.buffer()->width(), 174 acquired_buffer.buffer()->height(), 175 acquired_buffer.buffer()->buffer()->buffer(), 176 acquired_buffer.ClaimAcquireFence()); 177 } else { 178 return std::make_tuple(0, 0, nullptr, pdx::LocalHandle{}); 179 } 180 } 181 182 void Finish(pdx::LocalHandle fence) { release_fence = std::move(fence); } 183 184 // Gets a pointer to the current acquired buffer or returns nullptr if there 185 // isn't one. 186 IonBuffer* GetBuffer() { 187 if (acquired_buffer.IsAvailable()) 188 return acquired_buffer.buffer()->buffer(); 189 else 190 return nullptr; 191 } 192 193 // Returns the surface id of the surface. 194 int GetSurfaceId() { return surface->surface_id(); } 195 }; 196 197 // State when the layer is connected to a buffer. Provides the same interface 198 // as SourceSurface to simplify internal use by Layer. 199 struct SourceBuffer { 200 std::shared_ptr<IonBuffer> buffer; 201 202 std::tuple<int, int, sp<GraphicBuffer>, pdx::LocalHandle> Acquire() { 203 if (buffer) 204 return std::make_tuple(buffer->width(), buffer->height(), 205 buffer->buffer(), pdx::LocalHandle{}); 206 else 207 return std::make_tuple(0, 0, nullptr, pdx::LocalHandle{}); 208 } 209 210 void Finish(pdx::LocalHandle /*fence*/) {} 211 212 IonBuffer* GetBuffer() { return buffer.get(); } 213 214 int GetSurfaceId() const { return -1; } 215 }; 216 217 // The underlying hardware composer layer is supplied buffers either from a 218 // surface buffer train or from a buffer directly. 219 pdx::rpc::Variant<SourceSurface, SourceBuffer> source_; 220 221 pdx::LocalHandle acquire_fence_; 222 bool surface_rect_functions_applied_ = false; 223 224 Layer(const Layer&) = delete; 225 void operator=(const Layer&) = delete; 226}; 227 228// HardwareComposer encapsulates the hardware composer HAL, exposing a 229// simplified API to post buffers to the display. 230// 231// HardwareComposer is accessed by both the vr flinger dispatcher thread and the 232// surface flinger main thread, in addition to internally running a separate 233// thread for compositing/EDS and posting layers to the HAL. When changing how 234// variables are used or adding new state think carefully about which threads 235// will access the state and whether it needs to be synchronized. 236class HardwareComposer { 237 public: 238 // Type for vsync callback. 239 using VSyncCallback = std::function<void(int, int64_t, int64_t, uint32_t)>; 240 using RequestDisplayCallback = std::function<void(bool)>; 241 242 // Since there is no universal way to query the number of hardware layers, 243 // just set it to 4 for now. 244 static constexpr size_t kMaxHardwareLayers = 4; 245 246 HardwareComposer(); 247 HardwareComposer(Hwc2::Composer* hidl, 248 RequestDisplayCallback request_display_callback); 249 ~HardwareComposer(); 250 251 bool Initialize(); 252 253 bool IsInitialized() const { return initialized_; } 254 255 // Start the post thread if there's work to do (i.e. visible layers). This 256 // should only be called from surface flinger's main thread. 257 void Enable(); 258 // Pause the post thread, blocking until the post thread has signaled that 259 // it's paused. This should only be called from surface flinger's main thread. 260 void Disable(); 261 262 // Get the HMD display metrics for the current display. 263 display::Metrics GetHmdDisplayMetrics() const; 264 265 HWC::Error GetDisplayAttribute(hwc2_display_t display, hwc2_config_t config, 266 hwc2_attribute_t attributes, 267 int32_t* out_value) const; 268 HWC::Error GetDisplayMetrics(hwc2_display_t display, hwc2_config_t config, 269 HWCDisplayMetrics* out_metrics) const; 270 std::string Dump(); 271 272 void SetVSyncCallback(VSyncCallback callback); 273 274 // Metrics of the logical display, which is always landscape. 275 int DisplayWidth() const { return display_metrics_.width; } 276 int DisplayHeight() const { return display_metrics_.height; } 277 HWCDisplayMetrics display_metrics() const { return display_metrics_; } 278 279 // Metrics of the native display, which depends on the specific hardware 280 // implementation of the display. 281 HWCDisplayMetrics native_display_metrics() const { 282 return native_display_metrics_; 283 } 284 285 // Sets the display surfaces to compose the hardware layer stack. 286 void SetDisplaySurfaces( 287 std::vector<std::shared_ptr<DirectDisplaySurface>> surfaces); 288 289 void OnHardwareComposerRefresh(); 290 291 private: 292 int32_t EnableVsync(bool enabled); 293 294 class ComposerCallback : public Hwc2::IComposerCallback { 295 public: 296 ComposerCallback() {} 297 298 hardware::Return<void> onHotplug(Hwc2::Display /*display*/, 299 Connection /*connected*/) override { 300 // TODO(skiazyk): depending on how the server is implemented, we might 301 // have to set it up to synchronize with receiving this event, as it can 302 // potentially be a critical event for setting up state within the 303 // hwc2 module. That is, we (technically) should not call any other hwc 304 // methods until this method has been called after registering the 305 // callbacks. 306 return hardware::Void(); 307 } 308 309 hardware::Return<void> onRefresh(Hwc2::Display /*display*/) override { 310 return hardware::Void(); 311 } 312 313 hardware::Return<void> onVsync(Hwc2::Display /*display*/, 314 int64_t /*timestamp*/) override { 315 return hardware::Void(); 316 } 317 }; 318 319 HWC::Error Validate(hwc2_display_t display); 320 HWC::Error Present(hwc2_display_t display); 321 322 void SetBacklightBrightness(int brightness); 323 324 void PostLayers(); 325 void PostThread(); 326 327 // The post thread has two controlling states: 328 // 1. Idle: no work to do (no visible surfaces). 329 // 2. Suspended: explicitly halted (system is not in VR mode). 330 // When either #1 or #2 is true then the post thread is quiescent, otherwise 331 // it is active. 332 using PostThreadStateType = uint32_t; 333 struct PostThreadState { 334 enum : PostThreadStateType { 335 Active = 0, 336 Idle = (1 << 0), 337 Suspended = (1 << 1), 338 Quit = (1 << 2), 339 }; 340 }; 341 342 void UpdatePostThreadState(uint32_t state, bool suspend); 343 344 // Blocks until either event_fd becomes readable, or we're interrupted by a 345 // control thread. Any errors are returned as negative errno values. If we're 346 // interrupted, kPostThreadInterrupted will be returned. 347 int PostThreadPollInterruptible(const pdx::LocalHandle& event_fd, 348 int requested_events); 349 350 // BlockUntilVSync, WaitForVSync, and SleepUntil are all blocking calls made 351 // on the post thread that can be interrupted by a control thread. If 352 // interrupted, these calls return kPostThreadInterrupted. 353 int ReadWaitPPState(); 354 int BlockUntilVSync(); 355 int ReadVSyncTimestamp(int64_t* timestamp); 356 int WaitForVSync(int64_t* timestamp); 357 int SleepUntil(int64_t wakeup_timestamp); 358 359 bool IsFramePendingInDriver() { return ReadWaitPPState() == 1; } 360 361 // Reconfigures the layer stack if the display surfaces changed since the last 362 // frame. Called only from the post thread. 363 bool UpdateLayerConfig(); 364 365 // Called on the post thread when the post thread is resumed. 366 void OnPostThreadResumed(); 367 // Called on the post thread when the post thread is paused or quits. 368 void OnPostThreadPaused(); 369 370 bool initialized_; 371 372 // Hardware composer HAL device from SurfaceFlinger. VrFlinger does not own 373 // this pointer. 374 Hwc2::Composer* hwc2_hidl_; 375 RequestDisplayCallback request_display_callback_; 376 sp<ComposerCallback> callbacks_; 377 378 // Display metrics of the physical display. 379 HWCDisplayMetrics native_display_metrics_; 380 // Display metrics of the logical display, adjusted so that orientation is 381 // landscape. 382 HWCDisplayMetrics display_metrics_; 383 // Transform required to get from native to logical display orientation. 384 HWC::Transform display_transform_ = HWC::Transform::None; 385 386 // Buffer for the background layer required by hardware composer. 387 std::shared_ptr<IonBuffer> framebuffer_target_; 388 389 // Pending surface list. Set by the display service when DirectSurfaces are 390 // added, removed, or change visibility. Written by the message dispatch 391 // thread and read by the post thread. 392 std::vector<std::shared_ptr<DirectDisplaySurface>> pending_surfaces_; 393 394 // The surfaces displayed by the post thread. Used exclusively by the post 395 // thread. 396 std::vector<std::shared_ptr<DirectDisplaySurface>> display_surfaces_; 397 398 // Layer array for handling buffer flow into hardware composer layers. 399 std::array<Layer, kMaxHardwareLayers> layers_; 400 size_t active_layer_count_ = 0; 401 402 // Handler to hook vsync events outside of this class. 403 VSyncCallback vsync_callback_; 404 405 // The layer posting thread. This thread wakes up a short time before vsync to 406 // hand buffers to hardware composer. 407 std::thread post_thread_; 408 409 // Post thread state machine and synchronization primitives. 410 PostThreadStateType post_thread_state_{PostThreadState::Idle}; 411 std::atomic<bool> post_thread_quiescent_{true}; 412 bool post_thread_resumed_{false}; 413 pdx::LocalHandle post_thread_event_fd_; 414 std::mutex post_thread_mutex_; 415 std::condition_variable post_thread_wait_; 416 std::condition_variable post_thread_ready_; 417 418 // Backlight LED brightness sysfs node. 419 pdx::LocalHandle backlight_brightness_fd_; 420 421 // Primary display vsync event sysfs node. 422 pdx::LocalHandle primary_display_vsync_event_fd_; 423 424 // Primary display wait_pingpong state sysfs node. 425 pdx::LocalHandle primary_display_wait_pp_fd_; 426 427 // VSync sleep timerfd. 428 pdx::LocalHandle vsync_sleep_timer_fd_; 429 430 // The timestamp of the last vsync. 431 int64_t last_vsync_timestamp_ = 0; 432 433 // Vsync count since display on. 434 uint32_t vsync_count_ = 0; 435 436 // Counter tracking the number of skipped frames. 437 int frame_skip_count_ = 0; 438 439 // Fd array for tracking retire fences that are returned by hwc. This allows 440 // us to detect when the display driver begins queuing frames. 441 std::vector<pdx::LocalHandle> retire_fence_fds_; 442 443 // Pose client for frame count notifications. Pose client predicts poses 444 // out to display frame boundaries, so we need to tell it about vsyncs. 445 DvrPose* pose_client_ = nullptr; 446 447 static constexpr int kPostThreadInterrupted = 1; 448 449 static void HwcRefresh(hwc2_callback_data_t data, hwc2_display_t display); 450 static void HwcVSync(hwc2_callback_data_t data, hwc2_display_t display, 451 int64_t timestamp); 452 static void HwcHotplug(hwc2_callback_data_t callbackData, 453 hwc2_display_t display, hwc2_connection_t connected); 454 455 HardwareComposer(const HardwareComposer&) = delete; 456 void operator=(const HardwareComposer&) = delete; 457}; 458 459} // namespace dvr 460} // namespace android 461 462#endif // ANDROID_DVR_SERVICES_DISPLAYD_HARDWARE_COMPOSER_H_ 463