1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef UI_GFX_OZONE_DRI_HARDWARE_DISPLAY_CONTROLLER_H_ 6 #define UI_GFX_OZONE_DRI_HARDWARE_DISPLAY_CONTROLLER_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 #include <xf86drmMode.h> 11 #include <vector> 12 13 #include "base/basictypes.h" 14 #include "base/memory/scoped_ptr.h" 15 #include "ui/gfx/gfx_export.h" 16 #include "ui/gfx/ozone/dri/dri_wrapper.h" 17 18 namespace gfx { 19 20 class DriSurface; 21 22 // The HDCOz will handle modesettings and scannout operations for hardware 23 // devices. 24 // 25 // In the DRM world there are 3 components that need to be paired up to be able 26 // to display an image to the monitor: CRTC (cathode ray tube controller), 27 // encoder and connector. The CRTC determines which framebuffer to read, when 28 // to scanout and where to scanout. Encoders converts the stream from the CRTC 29 // to the appropriate format for the connector. The connector is the physical 30 // connection that monitors connect to. 31 // 32 // There is no 1:1:1 pairing for these components. It is possible for an encoder 33 // to be compatible to multiple CRTCs and each connector can be used with 34 // multiple encoders. In addition, it is possible to use one CRTC with multiple 35 // connectors such that we can display the same image on multiple monitors. 36 // 37 // For example, the following configuration shows 2 different screens being 38 // initialized separately. 39 // ------------- ------------- 40 // | Connector | | Connector | 41 // | HDMI | | VGA | 42 // ------------- ------------- 43 // ^ ^ 44 // | | 45 // ------------- ------------- 46 // | Encoder1 | | Encoder2 | 47 // ------------- ------------- 48 // ^ ^ 49 // | | 50 // ------------- ------------- 51 // | CRTC1 | | CRTC2 | 52 // ------------- ------------- 53 // 54 // In the following configuration 2 different screens are associated with the 55 // same CRTC, so on scanout the same framebuffer will be displayed on both 56 // monitors. 57 // ------------- ------------- 58 // | Connector | | Connector | 59 // | HDMI | | VGA | 60 // ------------- ------------- 61 // ^ ^ 62 // | | 63 // ------------- ------------- 64 // | Encoder1 | | Encoder2 | 65 // ------------- ------------- 66 // ^ ^ 67 // | | 68 // ---------------------- 69 // | CRTC1 | 70 // ---------------------- 71 // 72 // Note that it is possible to have more connectors than CRTCs which means that 73 // only a subset of connectors can be active independently, showing different 74 // framebuffers. Though, in this case, it would be possible to have all 75 // connectors active if some use the same CRTC to mirror the display. 76 // 77 // TODO(dnicoara) Need to have a way to detect events (such as monitor 78 // connected or disconnected). 79 class GFX_EXPORT HardwareDisplayController { 80 public: 81 // Controller states. The state transitions will happen from top to bottom. 82 enum State { 83 // When we allocate a HDCO as a stub. At this point there is no connector 84 // and CRTC associated with this device. 85 UNASSOCIATED, 86 87 // When |SetControllerInfo| is called and the HDCO has the information of 88 // the hardware it will control. At this point it knows everything it needs 89 // to control the hardware but doesn't have a surface. 90 UNINITIALIZED, 91 92 // A surface is associated with the HDCO. This means that the controller can 93 // potentially display the backing surface to the display. Though the 94 // surface framebuffer still needs to be registered with the CRTC. 95 SURFACE_INITIALIZED, 96 97 // The CRTC now knows about the surface attributes. 98 INITIALIZED, 99 100 // Error state if any of the initialization steps fail. 101 FAILED, 102 }; 103 104 HardwareDisplayController(); 105 106 ~HardwareDisplayController(); 107 108 // Set the hardware configuration for this HDCO. Once this is set, the HDCO is 109 // responsible for keeping track of the connector and CRTC and cleaning up 110 // when it is destroyed. 111 void SetControllerInfo(DriWrapper* drm, 112 uint32_t connector_id, 113 uint32_t crtc_id, 114 uint32_t dpms_property_id, 115 drmModeModeInfo mode); 116 117 // Associate the HDCO with a surface implementation and initialize it. 118 bool BindSurfaceToController(scoped_ptr<DriSurface> surface); 119 120 // Schedules the |surface_|'s framebuffer to be displayed on the next vsync 121 // event. The event will be posted on the graphics card file descriptor |fd_| 122 // and it can be read and processed by |drmHandleEvent|. That function can 123 // define the callback for the page flip event. A generic data argument will 124 // be presented to the callback. We use that argument to pass in the HDCO 125 // object the event belongs to. 126 // 127 // Between this call and the callback, the framebuffer used in this call 128 // should not be modified in any way as it would cause screen tearing if the 129 // hardware performed the flip. Note that the frontbuffer should also not 130 // be modified as it could still be displayed. 131 // 132 // Note that this function does not block. Also, this function should not be 133 // called again before the page flip occurrs. 134 // 135 // Returns true if the page flip was successfully registered, false otherwise. 136 bool SchedulePageFlip(); 137 138 // Called when the page flip event occurred. The event is provided by the 139 // kernel when a VBlank event finished. This allows the controller to 140 // update internal state and propagate the update to the surface. 141 // The tuple (seconds, useconds) represents the event timestamp. |seconds| 142 // represents the number of seconds while |useconds| represents the 143 // microseconds (< 1 second) in the timestamp. 144 void OnPageFlipEvent(unsigned int frame, 145 unsigned int seconds, 146 unsigned int useconds); 147 148 State get_state() const { return state_; }; 149 150 int get_fd() const { return drm_->get_fd(); }; 151 152 const drmModeModeInfo& get_mode() const { return mode_; }; 153 154 DriSurface* get_surface() const { return surface_.get(); }; 155 156 uint64_t get_time_of_last_flip() const { 157 return time_of_last_flip_; 158 }; 159 160 private: 161 // Object containing the connection to the graphics device and wraps the API 162 // calls to control it. 163 DriWrapper* drm_; 164 165 // TODO(dnicoara) Need to allow a CRTC to have multiple connectors. 166 uint32_t connector_id_; 167 168 uint32_t crtc_id_; 169 170 uint32_t dpms_property_id_; 171 172 // TODO(dnicoara) Need to store all the modes. 173 drmModeModeInfo mode_; 174 175 // Saved CRTC state from before we used it. Need it to restore state once we 176 // are finished using this device. 177 drmModeCrtc* saved_crtc_; 178 179 State state_; 180 181 scoped_ptr<DriSurface> surface_; 182 183 uint64_t time_of_last_flip_; 184 185 DISALLOW_COPY_AND_ASSIGN(HardwareDisplayController); 186 }; 187 188 } // namespace gfx 189 190 #endif // UI_GFX_OZONE_DRI_HARDWARE_DISPLAY_CONTROLLER_H_ 191
