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drm hwc 的知识点分析/记录

时间：2023-03-04 16:35:26浏览次数：43  
标签：case 知识点 ALOGD FORMAT -- hwc break drm DRM

基本的目录结构

.
|-- Android.bp
|-- backend
|   |-- Backend.cpp
|   |-- Backend.h
|   |-- BackendClient.cpp
|   |-- BackendClient.h
|   |-- BackendManager.cpp
|   `-- BackendManager.h
|-- bufferinfo
|   |-- BufferInfo.h
|   |-- BufferInfoGetter.cpp
|   |-- BufferInfoGetter.h
|   |-- BufferInfoMapperMetadata.cpp
|   `-- BufferInfoMapperMetadata.h
|-- compositor
|   |-- DrmKmsPlan.cpp
|   |-- DrmKmsPlan.h
|   |-- FlatteningController.cpp
|   |-- FlatteningController.h
|   `-- LayerData.h
|-- drm
|   |-- DrmAtomicStateManager.cpp
|   |-- DrmAtomicStateManager.h
|   |-- DrmConnector.cpp
|   |-- DrmConnector.h
|   |-- DrmCrtc.cpp
|   |-- DrmCrtc.h
|   |-- DrmDevice.cpp
|   |-- DrmDevice.h
|   |-- DrmDisplayPipeline.cpp
|   |-- DrmDisplayPipeline.h
|   |-- DrmEncoder.cpp
|   |-- DrmEncoder.h
|   |-- DrmFbImporter.cpp
|   |-- DrmFbImporter.h
|   |-- DrmMode.cpp
|   |-- DrmMode.h
|   |-- DrmPlane.cpp
|   |-- DrmPlane.h
|   |-- DrmProperty.cpp
|   |-- DrmProperty.h
|   |-- DrmUnique.h
|   |-- ResourceManager.cpp
|   |-- ResourceManager.h
|   |-- UEventListener.cpp
|   |-- UEventListener.h
|   |-- VSyncWorker.cpp
|   `-- VSyncWorker.h
|-- hwc2_device
|   |-- DrmHwcTwo.cpp
|   |-- DrmHwcTwo.h
|   |-- HwcDisplay.cpp
|   |-- HwcDisplay.h
|   |-- HwcDisplayConfigs.cpp
|   |-- HwcDisplayConfigs.h
|   |-- HwcLayer.cpp
|   |-- HwcLayer.h
|   `-- hwc2_device.cpp
`-- utils
    |-- UEvent.h
    |-- fd.cpp
    |-- fd.h
    |-- log.h
    `-- properties.h

 

HwcDisplay中定义的变量：

std::map<hwc2_layer_t, HwcLayer> layers_;map数组，把SF的layer 与 HWC layer 一一映射，用于对应用图层和合成图层进行管理，看定义 hwc2_layer_t 就是一个 uint64_t的数值

typedef uint64_t hwc2_layer_t;


HwcLayer client_layer_;专用于GPU合成的特殊图层 HWC layer

CreateLayer / DestroyLayer 时会去更新 layers_ ; 还有一个单调递增的计数器 uint32_t layer_idx_ 代表了下一个要创建的hwc layer的index

HWC2::Error HwcDisplay::CreateLayer(hwc2_layer_t *layer) {
    layers_.emplace(static_cast<hwc2_layer_t>(layer_idx_), HwcLayer(this));
    *layer = static_cast<hwc2_layer_t>(layer_idx_);
    ++layer_idx_;
    return HWC2::Error::None;
}

HWC2::Error HwcDisplay::DestroyLayer(hwc2_layer_t layer) {
    if (!get_layer(layer)) {
        return HWC2::Error::BadLayer;
    }

    layers_.erase(layer);
    return HWC2::Error::None;
}

 

Backend::HardwareSupportsLayerType 判断是否是硬件支持的合成类型，这里应根据硬件能力适配调整

bool Backend::HardwareSupportsLayerType(HWC2::Composition comp_type) {
  return comp_type == HWC2::Composition::Device ||
         comp_type == HWC2::Composition::Cursor;
}

 

bi_get_failed_  get buffer information failed or not

fb_import_failed_ import frame buffer failed or not

buffer_handle_ layer通过SetLayerBuffer设置下来的buffer handle

 

 

ResourceManager::Init() 初始化时有几个属性值

"vendor.hwc.drm.device" ==> DRM 设备路径

"vendor.hwc.drm.scale_with_gpu" ==> 比例缩放是否由GPU做

"vendor.hwc.drm.ctm" ==> 取值 kDrmOrGpu or kDrmOrIgnore  解释看定义

enum class CtmHandling {
  kDrmOrGpu,    /* Handled by DRM is possible, otherwise by GPU */
  kDrmOrIgnore, /* Handled by DRM is possible, otherwise displayed as is */
};

 

 

 

 

那么一个Layer的合成方式是怎么确定的那？大致流程如下所示：

 

  1. 当VSync信号到来时，SurfaceFlinger被唤醒，处理Layer的新建，销毁和更新，并且为相应Layer设置期望的合成方式。
  2. 所有Layer更新后，SurfaceFlinger调用validateDisplay，让HWC决定每个Layer的合成方式。
  3. SurfaceFlinger调用getChangedCompositionTypes检查HWC是否对任何Layer的合成方式做出了改变，若是，那么SurfaceFlinger则调整对应Layer的合成方式，并且调用acceptDisplayChanges通知HWC。
  4. SurfaceFlinger把所有Client类型的Layer合成到Target图形缓冲区，然后调用setClientTarget把Target Buffer设置给HWC。（如果没有Client类型的Layer，则可以跳过该方法）
  5. 最后，SurfaceFlinger调用presentDisplay，让HWC完成剩余Layer的合成，并且在显示屏上展示出最终的合成结果。

 

 

 

switch (layer_data_.bi->format) {
    ALOGD("format 0x%08x\n",  layer_data_.bi->format);
	case DRM_FORMAT_C8: ALOGD("DRM_FORMAT_C8");break;
	case DRM_FORMAT_NV12: ALOGD("DRM_FORMAT_NV12");break;
	case DRM_FORMAT_NV21: ALOGD("DRM_FORMAT_NV21");break;
	case DRM_FORMAT_NV16: ALOGD("DRM_FORMAT_NV16");break;
	case DRM_FORMAT_NV61: ALOGD("DRM_FORMAT_NV61");break;
	case DRM_FORMAT_YUV420: ALOGD("DRM_FORMAT_YUV420");break;
	case DRM_FORMAT_YVU420: ALOGD("DRM_FORMAT_YVU420");break;
	case DRM_FORMAT_ARGB4444: ALOGD("DRM_FORMAT_ARGB4444");break;
	case DRM_FORMAT_XRGB4444: ALOGD("DRM_FORMAT_XRGB4444");break;
	case DRM_FORMAT_ABGR4444: ALOGD("DRM_FORMAT_ABGR4444");break;
	case DRM_FORMAT_XBGR4444: ALOGD("DRM_FORMAT_XBGR4444");break;
	case DRM_FORMAT_RGBA4444: ALOGD("DRM_FORMAT_RGBA4444");break;
	case DRM_FORMAT_RGBX4444: ALOGD("DRM_FORMAT_RGBX4444");break;
	case DRM_FORMAT_BGRA4444: ALOGD("DRM_FORMAT_BGRA4444");break;
	case DRM_FORMAT_BGRX4444: ALOGD("DRM_FORMAT_BGRX4444");break;
	case DRM_FORMAT_ARGB1555: ALOGD("DRM_FORMAT_ARGB1555");break;
	case DRM_FORMAT_XRGB1555: ALOGD("DRM_FORMAT_XRGB1555");break;
	case DRM_FORMAT_ABGR1555: ALOGD("DRM_FORMAT_ABGR1555");break;
	case DRM_FORMAT_XBGR1555: ALOGD("DRM_FORMAT_XBGR1555");break;
	case DRM_FORMAT_RGBA5551: ALOGD("DRM_FORMAT_RGBA5551");break;
	case DRM_FORMAT_RGBX5551: ALOGD("DRM_FORMAT_RGBX5551");break;
	case DRM_FORMAT_BGRA5551: ALOGD("DRM_FORMAT_BGRA5551");break;
	case DRM_FORMAT_BGRX5551: ALOGD("DRM_FORMAT_BGRX5551");break;
	case DRM_FORMAT_RGB565: ALOGD("DRM_FORMAT_RGB565");break;
	case DRM_FORMAT_BGR565: ALOGD("DRM_FORMAT_BGR565");break;
	case DRM_FORMAT_UYVY: ALOGD("DRM_FORMAT_UYVY");break;
	case DRM_FORMAT_VYUY: ALOGD("DRM_FORMAT_VYUY");break;
	case DRM_FORMAT_YUYV: ALOGD("DRM_FORMAT_YUYV");break;
	case DRM_FORMAT_YVYU: ALOGD("DRM_FORMAT_YVYU");break;
	case DRM_FORMAT_BGR888: ALOGD("DRM_FORMAT_BGR888");break;
	case DRM_FORMAT_RGB888: ALOGD("DRM_FORMAT_RGB888");break;
	case DRM_FORMAT_ARGB8888: ALOGD("DRM_FORMAT_ARGB8888");break;
	case DRM_FORMAT_XRGB8888: ALOGD("DRM_FORMAT_XRGB8888");break;
	case DRM_FORMAT_ABGR8888: ALOGD("DRM_FORMAT_ABGR8888");break;
	case DRM_FORMAT_XBGR8888: ALOGD("DRM_FORMAT_XBGR8888");break;
	case DRM_FORMAT_RGBA8888: ALOGD("DRM_FORMAT_RGBA8888");break;
	case DRM_FORMAT_RGBX8888: ALOGD("DRM_FORMAT_RGBX8888");break;
	case DRM_FORMAT_BGRA8888: ALOGD("DRM_FORMAT_BGRA8888");break;
	case DRM_FORMAT_BGRX8888: ALOGD("DRM_FORMAT_BGRX8888");break;
	case DRM_FORMAT_ARGB2101010: ALOGD("DRM_FORMAT_ARGB2101010");break;
	case DRM_FORMAT_XRGB2101010: ALOGD("DRM_FORMAT_XRGB2101010");break;
	case DRM_FORMAT_ABGR2101010: ALOGD("DRM_FORMAT_ABGR2101010");break;
	case DRM_FORMAT_XBGR2101010: ALOGD("DRM_FORMAT_XBGR2101010");break;
	case DRM_FORMAT_RGBA1010102: ALOGD("DRM_FORMAT_RGBA1010102");break;
	case DRM_FORMAT_RGBX1010102: ALOGD("DRM_FORMAT_RGBX1010102");break;
	case DRM_FORMAT_BGRA1010102: ALOGD("DRM_FORMAT_BGRA1010102");break;
	case DRM_FORMAT_BGRX1010102: ALOGD("DRM_FORMAT_BGRX1010102");break;
	case DRM_FORMAT_XRGB16161616F: ALOGD("DRM_FORMAT_XRGB16161616F");break;
	case DRM_FORMAT_XBGR16161616F: ALOGD("DRM_FORMAT_XBGR16161616F");break;
	case DRM_FORMAT_ARGB16161616F: ALOGD("DRM_FORMAT_ARGB16161616F");break;
	case DRM_FORMAT_ABGR16161616F: ALOGD("DRM_FORMAT_ABGR16161616F");break;
	default: break;
}

 

 

 

 

02-14 18:41:17.833 22358 22358 D drm_render: yuv-YV12 address: y = 0xecc16000, cr = 0xece32000, cb = 0xeceb9000
02-14 18:41:17.833 22358 22358 D drm_render: yuv-YV12 address offset: cr-b=2211840, cb-y =2764800
02-14 18:41:17.833 22358 22358 D drm_render: yuv-YV12 ystride = 2048, cstride = 1024
02-14 18:41:17.994 22358 22358 D drm_render: buffer_handle_t ==> i=0, fd=9
02-14 18:41:17.994 22358 22358 D drm_render: buffer_handle_t ==> i=1, fd=10
02-14 18:41:17.994 22358 22358 D drm_render: width=1920, height=1080, format=842094169, hal_format=842094169, usage=4912
02-14 18:41:17.995 22358 22358 D drm_render: pitches[0]=2048, offsets[0]=0, gem_handles[0]=1, prime_fds[0]=9
02-14 18:41:17.995 22358 22358 D drm_render: pitches[1]=1024, offsets[1]=2211840, gem_handles[1]=1, prime_fds[1]=9
02-14 18:41:17.995 22358 22358 D drm_render: pitches[2]=1024, offsets[2]=2764800, gem_handles[2]=1, prime_fds[2]=9
02-14 18:41:17.995 22358 22358 D drm_render: pitches[3]=0, offsets[3]=0, gem_handles[3]=0, prime_fds[3]=0
    
    
    
02-14 18:41:20.832 22371 22371 D drm_render: yuv-NV12 address: y = 0xed048000, cr = 0xed242401, cb = 0xed242400
02-14 18:41:20.832 22371 22371 D drm_render: yuv-NV12 address offset: cr-b=2073601, cb-y =2073600
02-14 18:41:20.832 22371 22371 D drm_render: yuv-NV12 ystride = 1920, cstride = 1920
02-14 18:41:20.994 22371 22371 D drm_render: buffer_handle_t ==> i=0, fd=9
02-14 18:41:20.995 22371 22371 D drm_render: buffer_handle_t ==> i=1, fd=10
02-14 18:41:20.995 22371 22371 D drm_render: width=1920, height=1080, format=842094158, hal_format=114, usage=4912
02-14 18:41:20.995 22371 22371 D drm_render: pitches[0]=1920, offsets[0]=0, gem_handles[0]=1, prime_fds[0]=9
02-14 18:41:20.995 22371 22371 D drm_render: pitches[1]=1920, offsets[1]=2073600, gem_handles[1]=1, prime_fds[1]=9
02-14 18:41:20.995 22371 22371 D drm_render: pitches[2]=0, offsets[2]=0, gem_handles[2]=1, prime_fds[2]=9
02-14 18:41:20.995 22371 22371 D drm_render: pitches[3]=0, offsets[3]=0, gem_handles[3]=0, prime_fds[3]=0

 

 

--

 

uevent_listener_ = UEventListener::CreateInstance(); UEventListener是如何检测及处理hotplug事件的？

  uevent_listener_->RegisterHotplugHandler([this] {
    const std::unique_lock lock(GetMainLock());
    UpdateFrontendDisplays();
  });

 

 

 

Drmhwc2Device 有一个成员 DrmHwcTwo drmhwctwo；

DrmHwcTwo 有一个成员 ResourceManager resource_manager_;

ResourceManager 有一个成员 std::vector<std::unique_ptr<DrmDevice>> drms_; 这是一个数组

DrmDevice 有一系列成员，代表DRM相关的资源

  std::vector<std::unique_ptr<DrmConnector>> connectors_;
  std::vector<std::unique_ptr<DrmConnector>> writeback_connectors_;
  std::vector<std::unique_ptr<DrmEncoder>> encoders_;
  std::vector<std::unique_ptr<DrmCrtc>> crtcs_;
  std::vector<std::unique_ptr<DrmPlane>> planes_;

DrmDevice 有一个成员 std::unique_ptr<DrmFbImporter> drm_fb_importer_;

 

 

 

 

 

 

 

 

 

Encoders:
id      crtc    type    possible crtcs  possible clones
38      35      TMDS    0x00000001      0x00000000

Connectors:
id      encoder status          name            size (mm)       modes   encoders
39      38      connected       HDMI-A-1        530x300         9       38
  modes:
        index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot
  #0 1920x1080 60.00 1920 2008 2052 2200 1080 1084 1089 1125 148500 flags: phsync, pvsync; type: preferred, driver
  #1 1920x1080 59.94 1920 2008 2052 2200 1080 1084 1089 1125 148352 flags: phsync, pvsync; type: driver
  #2 1920x1080 50.00 1920 2448 2492 2640 1080 1084 1089 1125 148500 flags: phsync, pvsync; type: driver
  #3 1280x720 60.00 1280 1390 1430 1650 720 725 730 750 74250 flags: phsync, pvsync; type: driver
  #4 1280x720 59.94 1280 1390 1430 1650 720 725 730 750 74176 flags: phsync, pvsync; type: driver
  #5 1280x720 50.00 1280 1720 1760 1980 720 725 730 750 74250 flags: phsync, pvsync; type: driver
  #6 720x576 50.00 720 732 796 864 576 581 586 625 27000 flags: nhsync, nvsync; type: driver
  #7 720x480 60.00 720 736 798 858 480 489 495 525 27027 flags: nhsync, nvsync; type: driver
  #8 720x480 59.94 720 736 798 858 480 489 495 525 27000 flags: nhsync, nvsync; type: driver
  props:
        1 EDID:
                flags: immutable blob
                blobs:

                value:
                        00ffffffffffff00410c100001010101
                        0019010380351e782a4789a357479f22
                        11484cbfef80b300950081808140714f
                        010101010101023a801871382d40582c
                        450009252100001e662150b051001b30
                        4070360009252100001e000000fd0037
                        4c1e5211000a202020202020000000fc
                        003234504646333535352f54330a016c
                        020322f24f9f14131211161590050403
                        02070601230907018301000065030c00
                        1000023a80d072382d40102c45800925
                        2100001e011d80d0721c1620102c2500
                        09252100009e011d00bc52d01e20b828
                        55400925210000188c0ad09020403120
                        0c405500092521000018023a80187138
                        2d40582c450009252100001e00000026
        2 DPMS:
                flags: enum
                enums: On=0 Standby=1 Suspend=2 Off=3
                value: 0
        5 link-status:
                flags: enum
                enums: Good=0 Bad=1
                value: 0
        6 non-desktop:
                flags: immutable range
                values: 0 1
                value: 0
        4 TILE:
                flags: immutable blob
                blobs:

                value:
        40 RGB or YCbCr:
                flags: enum
                enums: RGB=0 Y422=1 Y444=2 Y420=3
                value: 0
        41 HDR mode:
                flags: enum
                enums: AUTO=0 DV_ON=1 SDR=2 HDR_GAMMA=3 PQHDR=4 FUTURE=5 INPUT=6 DV_LL_12b_Y422=7 DV_LL_10b_Y444=8 DV_LL_10b_RGB=9 DV_LL_12b_Y444=10 DV_LL_12b_RGB=11 DV_ON_INPUT=12 DV_LL_12b422_INPUT=13 INPUT_BT2020=14
                value: 2
        42 fractional fps:
                flags: enum
                enums: Disable=0 Enable=1
                value: 0
        43 allm:
                flags: enum
                enums: Unsupported=0 Disable=1 Enable=2
                value: 0
        44 qms_vrr:
                flags: enum
                enums: Unsupported=255 Disable=0 Enable_VRR=1 Enable_QMS=2
                value: 255
        45 vrr_rate:
                flags: enum
                enums: UNSPECIFIED=255 RATE_23HZ=9 RATE_24HZ=3 RATE_25HZ=8 RATE_29HZ=7 RATE_30HZ=6 RATE_47HZ=5 RATE_48HZ=2 RATE_50HZ=1 RATE_59HZ=4 RATE_60HZ=0 RATE_BASE=254
                value: 255
        46 max bpc:
                flags: range
                values: 8 12
                value: 0
        47 Content Protection:
                flags: enum
                enums: Undesired=0 Desired=1 Enabled=2
                value: 0
        48 HDCP Content Type:
                flags: enum
                enums: HDCP Type0=0 HDCP Type1=1
                value: 0
        49 hdcp14_timout:
                flags: range
                values: 0 300
                value: 5

CRTCs:
id      fb      pos     size
35      51      (0,0)   (1920x1080)
  #0 1920x1080 60.00 1920 2008 2052 2200 1080 1084 1089 1125 148500 flags: phsync, pvsync; type: preferred, driver
  props:
        24 VRR_ENABLED:
                flags: range
                values: 0 1
                value: 0

Planes:
id      crtc    fb      CRTC x,y        x,y     gamma size      possible crtcs
31      35      53      0,0             0,0     0               0x00000001
  formats: XR24 AR24 RG16 RG24 BG24 UYVY YUYV YU16 YU12 YV12 NV12 NV21
  props:
        8 type:
                flags: immutable enum
                enums: Overlay=0 Primary=1 Cursor=2
                value: 1
        30 IN_FORMATS:
                flags: immutable blob
                blobs:

                value:
                        01000000000000000c00000018000000
                        00000000480000005852323441523234
                        52473136524732344247323455595659
                        59555956595531365955313259563132
                        4e5631324e563231
                in_formats blob decoded:
                         XR24:
                         AR24:
                         RG16:
                         RG24:
                         BG24:
                         UYVY:
                         YUYV:
                         YU16:
                         YU12:
                         YV12:
                         NV12:
                         NV21:
33      0       0       0,0             0,0     0               0x00000001
  formats: XR24 AR24 RG16 RG24 BG24 UYVY YUYV YU16 YU12 YV12 NV12 NV21
  props:
        8 type:
                flags: immutable enum
                enums: Overlay=0 Primary=1 Cursor=2
                value: 2
        30 IN_FORMATS:
                flags: immutable blob
                blobs:

                value:
                        01000000000000000c00000018000000
                        00000000480000005852323441523234
                        52473136524732344247323455595659
                        59555956595531365955313259563132
                        4e5631324e563231
                in_formats blob decoded:
                         XR24:
                         AR24:
                         RG16:
                         RG24:
                         BG24:
                         UYVY:
                         YUYV:
                         YU16:
                         YU12:
                         YV12:
                         NV12:
                         NV21:
36      0       0       0,0             0,0     0               0x00000001
  formats: XR24 AR24 RG16 RG24 BG24 UYVY YUYV YU16 YU12 YV12 NV12 NV21
  props:
        8 type:
                flags: immutable enum
                enums: Overlay=0 Primary=1 Cursor=2
                value: 0
        30 IN_FORMATS:
                flags: immutable blob
                blobs:

                value:
                        01000000000000000c00000018000000
                        00000000480000005852323441523234
                        52473136524732344247323455595659
                        59555956595531365955313259563132
                        4e5631324e563231
                in_formats blob decoded:
                         XR24:
                         AR24:
                         RG16:
                         RG24:
                         BG24:
                         UYVY:
                         YUYV:
                         YU16:
                         YU12:
                         YV12:
                         NV12:
                         NV21:

Frame buffers:
id      size    pitch

 

 

 

 

 

 

 

 

标签：case,知识点,ALOGD,FORMAT,--,hwc,break,drm,DRM
From： https://www.cnblogs.com/roger-yu/p/17152637.html

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