FramebufferSurface.cpp

/*
 ** Copyright (C) 2020 KAI OS TECHNOLOGIES (HONG KONG) LIMITED. All rights reserved.
 ** Copyright 2012 The Android Open Source Project
 **
 ** Licensed under the Apache License Version 2.0(the "License");
 ** you may not use this file except in compliance with the License.
 ** You may obtain a copy of the License at
 **
 **     http://www.apache.org/licenses/LICENSE-2.0
 **
 ** Unless required by applicable law or agreed to in writing software
 ** distributed under the License is distributed on an "AS IS" BASIS
 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND either express or implied.
 ** See the License for the specific language governing permissions and
 ** limitations under the License.
 */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <cutils/log.h>
#include <EGL/egl.h>
#include <gui/BufferItem.h>
#include <gui/BufferQueue.h>
#include <gui/Surface.h>
#include <hardware/hardware.h>
#include <ui/GraphicBuffer.h>
#include <ui/Rect.h>
#include <utils/String8.h>
#include <vndk/hardware_buffer.h>

#include "GonkDisplayWorkThread.h"

#include "FramebufferSurface.h"
#include "ComposerHal_stub.h"

#ifndef NUM_FRAMEBUFFER_SURFACE_BUFFERS
#define NUM_FRAMEBUFFER_SURFACE_BUFFERS (3)
#endif

#ifdef LOG_TAG
#undef LOG_TAG
#define LOG_TAG "FramebufferSurface"
#endif

// ----------------------------------------------------------------------------
namespace android {
// ----------------------------------------------------------------------------

/*
 * This implements the (main) framebuffer management. This class
 * was adapted from the version in SurfaceFlinger
 */
FramebufferSurface::FramebufferSurface(
    uint32_t width, uint32_t height, uint32_t format,
    const sp<IGraphicBufferConsumer>& consumer,
    HWC2::Display *aHwcDisplay, HWC2::Layer *aLayer,
    NativeFramebufferDevice *ExtFBDevice)
    : DisplaySurface(consumer)
    , mCurrentSlot(BufferQueue::INVALID_BUFFER_SLOT)
    , mCurrentBuffer()
    , mPrevFBAcquireFence(Fence::NO_FENCE)
    , mHasPendingRelease(false)
    , mPreviousBufferSlot(BufferQueue::INVALID_BUFFER_SLOT)
    , mPreviousBuffer()
    , hwcDisplay(aHwcDisplay)
    , layer(aLayer)
    , mExtFBDevice(ExtFBDevice)
    , mLastPresentFence(Fence::NO_FENCE)
{
    mName = "FramebufferSurface";

    mConsumer->setConsumerName(mName);
    mConsumer->setConsumerUsageBits(
#if ANDROID_EMULATOR
                                    GRALLOC_USAGE_HW_FB |
#endif
                                    GRALLOC_USAGE_HW_RENDER |
                                    GRALLOC_USAGE_HW_COMPOSER);
    mConsumer->setDefaultBufferFormat(format);
    mConsumer->setDefaultBufferSize(width, height);
    mConsumer->setMaxAcquiredBufferCount(NUM_FRAMEBUFFER_SURFACE_BUFFERS);
}

void FramebufferSurface::resizeBuffers(const uint32_t width,
    const uint32_t height)
{
    mConsumer->setDefaultBufferSize(width, height);
}

status_t FramebufferSurface::beginFrame(bool /*mustRecompose*/)
{
    return NO_ERROR;
}

status_t FramebufferSurface::prepareFrame(CompositionType /*compositionType*/)
{
    return NO_ERROR;
}

status_t FramebufferSurface::advanceFrame()
{
    sp<GraphicBuffer> buf;
    sp<Fence> acquireFence;
    status_t result = nextBuffer(buf, acquireFence);
    if (result != NO_ERROR) {
        ALOGE("error latching next FramebufferSurface buffer: %s (%d)",
                strerror(-result), result);
    }

    if (acquireFence.get() && acquireFence->isValid()) {
        mPrevFBAcquireFence = new Fence(acquireFence->dup());
    } else {
        mPrevFBAcquireFence = Fence::NO_FENCE;
    }

    lastHandle = buf->handle;

	return result;
}

status_t FramebufferSurface::nextBuffer(sp<GraphicBuffer>& outBuffer,
    sp<Fence>& outFence)
{
    Mutex::Autolock lock(mMutex);
    BufferItem item;
    status_t err = acquireBufferLocked(&item, 0);

    if (err == BufferQueue::NO_BUFFER_AVAILABLE) {
        outBuffer = mCurrentBuffer;
        return NO_ERROR;
    } else if (err != NO_ERROR) {
        ALOGE("error acquiring buffer: %s (%d)", strerror(-err), err);
        return err;
    }

    const auto slot = item.mSlot;
    const auto buffer = mSlots[item.mSlot].mGraphicBuffer;
    const auto acquireFence = item.mFence;
    presentLocked(slot, buffer, acquireFence);

    // If the BufferQueue has freed and reallocated a buffer in mCurrentSlot
    // then we may have acquired the slot we already own.  If we had released
    // our current buffer before we call acquireBuffer then that release call
    // would have returned STALE_BUFFER_SLOT, and we would have called
    // freeBufferLocked on that slot.  Because the buffer slot has already
    // been overwritten with the new buffer all we have to do is skip the
    // releaseBuffer call and we should be in the same state we'd be in if we
    // had released the old buffer first.
    if (mCurrentSlot != BufferQueue::INVALID_BUFFER_SLOT && slot != mCurrentSlot) {
        mHasPendingRelease = true;
        mPreviousBufferSlot = mCurrentSlot;
        mPreviousBuffer = mCurrentBuffer;
    }

    mCurrentSlot = slot;
    outBuffer = mCurrentBuffer = buffer;
    outFence = acquireFence;
    return NO_ERROR;
}

// Overrides ConsumerBase::onFrameAvailable(), does not call base class impl.
void FramebufferSurface::onFrameAvailable(const BufferItem &item) {
    (void)item;
    carthage::GonkDisplayWorkThread::Get()->Post([=] {
        sp<GraphicBuffer> buf;
        sp<Fence> acquireFence;
        status_t err = nextBuffer(buf, acquireFence);
        if (err != NO_ERROR) {
            ALOGE("error latching nnext FramebufferSurface buffer: %s (%d)",
                    strerror(-err), err);
            return;
        }

        if (acquireFence.get() && acquireFence->isValid()) {
            mPrevFBAcquireFence = acquireFence;
        } else {
            mPrevFBAcquireFence = Fence::NO_FENCE;
        }

        lastHandle = buf->handle;
    });
}

void FramebufferSurface::presentLocked(const int slot,
                                 const sp<GraphicBuffer>& buffer,
                                 const sp<Fence>& acquireFence)
{
    uint32_t numTypes = 0;
    uint32_t numRequests = 0;
    HWC2::Error error = HWC2::Error::None;
    ui::Dataspace dataspace = ui::Dataspace::UNKNOWN;

    // TODO user HWC::Device path:
    //layer->setCompositionType(HWC2::Composition::Device);
    //layer->setBuffer(slot, buffer, acquireFence);
    // this line is used to avoid unused variable layer warning.
    (void)layer;
    if (mExtFBDevice) {
        if (acquireFence.get() && acquireFence->isValid()) {
            android::sp<Fence> fenceObj = new Fence(acquireFence->dup());
            fenceObj->waitForever("FramebufferSurface::Post");
        }
        mExtFBDevice->Post(buffer->handle);
    } else {
        error = hwcDisplay->validate(&numTypes, &numRequests);
        if (error != HWC2::Error::None && error != HWC2::Error::HasChanges) {
            ALOGE("prepare: validate failed : %s (%d)",
                to_string(error).c_str(), static_cast<int32_t>(error));
            goto FrameCommitted;
        }

        if (numTypes || numRequests) {
            ALOGE("prepare: validate required changes : %s (%d)",
                to_string(error).c_str(), static_cast<int32_t>(error));
            goto FrameCommitted;
        }

        error = hwcDisplay->acceptChanges();
        if (error != HWC2::Error::None) {
            ALOGE("prepare: acceptChanges failed: %s", to_string(error).c_str());
            goto FrameCommitted;
        }

        (void)hwcDisplay->setClientTarget(slot, buffer, acquireFence, dataspace);

        error = hwcDisplay->present(&mLastPresentFence);
        if (error != HWC2::Error::None) {
            ALOGE("present: failed : %s (%d)",
                to_string(error).c_str(), static_cast<int32_t>(error));
        }

    }

    FrameCommitted:
        onFrameCommitted();
}

void FramebufferSurface::freeBufferLocked(int slotIndex)
{
    ConsumerBase::freeBufferLocked(slotIndex);
    if (slotIndex == mCurrentSlot) {
        mCurrentSlot = BufferQueue::INVALID_BUFFER_SLOT;
    }
}

status_t FramebufferSurface::setReleaseFenceFd(int fenceFd)
{
    status_t err = NO_ERROR;
    if (fenceFd >= 0) {
        sp<Fence> fence(new Fence(fenceFd));
        if (mCurrentSlot != BufferQueue::INVALID_BUFFER_SLOT) {
            status_t err = addReleaseFence(mCurrentSlot,
			      mCurrentBuffer,  fence);
            ALOGE_IF(err, "setReleaseFenceFd: failed to add the fence: %s (%d)",
                    strerror(-err), err);
        }
    }
    return err;
}

int FramebufferSurface::GetPrevDispAcquireFd()
{
    if (mPrevFBAcquireFence.get() && mPrevFBAcquireFence->isValid()) {
        return mPrevFBAcquireFence->dup();
    }
    return -1;
}

void FramebufferSurface::onFrameCommitted()
{
    if (mHasPendingRelease) {
        addReleaseFenceLocked(mPreviousBufferSlot, mPreviousBuffer, mLastPresentFence);
        releaseBufferLocked(mPreviousBufferSlot, mPreviousBuffer);
        mHasPendingRelease = false;
    }
}

// ----------------------------------------------------------------------------
}; // namespace android
// ----------------------------------------------------------------------------