path: root/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmscreen.cpp

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Copyright (C) 2015 Pier Luigi Fiorini <pierluigi.fiorini@gmail.com>
** Copyright (C) 2016 Pelagicore AG
** Contact: https://www.qt.io/licensing/
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#include "qeglfskmsgbmscreen.h"
#include "qeglfskmsgbmdevice.h"
#include "qeglfskmsgbmcursor.h"
#include "qeglfsintegration_p.h"

#include <QtCore/QLoggingCategory>

#include <QtGui/private/qguiapplication_p.h>
#include <QtFbSupport/private/qfbvthandler_p.h>

#include <errno.h>

QT_BEGIN_NAMESPACE

Q_DECLARE_LOGGING_CATEGORY(qLcEglfsKmsDebug)

static inline uint32_t drmFormatToGbmFormat(uint32_t drmFormat)
{
    Q_ASSERT(DRM_FORMAT_XRGB8888 == GBM_FORMAT_XRGB8888);
    return drmFormat;
}

static inline uint32_t gbmFormatToDrmFormat(uint32_t gbmFormat)
{
    Q_ASSERT(DRM_FORMAT_XRGB8888 == GBM_FORMAT_XRGB8888);
    return gbmFormat;
}

void QEglFSKmsGbmScreen::bufferDestroyedHandler(gbm_bo *bo, void *data)
{
    FrameBuffer *fb = static_cast<FrameBuffer *>(data);

    if (fb->fb) {
        gbm_device *device = gbm_bo_get_device(bo);
        drmModeRmFB(gbm_device_get_fd(device), fb->fb);
    }

    delete fb;
}

QEglFSKmsGbmScreen::FrameBuffer *QEglFSKmsGbmScreen::framebufferForBufferObject(gbm_bo *bo)
{
    {
        FrameBuffer *fb = static_cast<FrameBuffer *>(gbm_bo_get_user_data(bo));
        if (fb)
            return fb;
    }

    uint32_t width = gbm_bo_get_width(bo);
    uint32_t height = gbm_bo_get_height(bo);
    uint32_t handles[4] = { gbm_bo_get_handle(bo).u32 };
    uint32_t strides[4] = { gbm_bo_get_stride(bo) };
    uint32_t offsets[4] = { 0 };
    uint32_t pixelFormat = gbmFormatToDrmFormat(gbm_bo_get_format(bo));

    QScopedPointer<FrameBuffer> fb(new FrameBuffer);
    qCDebug(qLcEglfsKmsDebug, "Adding FB, size %ux%u, DRM format 0x%x", width, height, pixelFormat);

    int ret = drmModeAddFB2(device()->fd(), width, height, pixelFormat,
                            handles, strides, offsets, &fb->fb, 0);

    if (ret) {
        qWarning("Failed to create KMS FB!");
        return Q_NULLPTR;
    }

    gbm_bo_set_user_data(bo, fb.data(), bufferDestroyedHandler);
    return fb.take();
}

QEglFSKmsGbmScreen::QEglFSKmsGbmScreen(QKmsDevice *device, const QKmsOutput &output)
    : QEglFSKmsScreen(device, output)
    , m_gbm_surface(Q_NULLPTR)
    , m_gbm_bo_current(Q_NULLPTR)
    , m_gbm_bo_next(Q_NULLPTR)
    , m_flipPending(false)
    , m_cursor(Q_NULLPTR)
    , m_cloneSource(Q_NULLPTR)
{
}

QEglFSKmsGbmScreen::~QEglFSKmsGbmScreen()
{
    const int remainingScreenCount = qGuiApp->screens().count();
    qCDebug(qLcEglfsKmsDebug, "Screen dtor. Remaining screens: %d", remainingScreenCount);
    if (!remainingScreenCount && !device()->screenConfig()->separateScreens())
        static_cast<QEglFSKmsGbmDevice *>(device())->destroyGlobalCursor();
}

QPlatformCursor *QEglFSKmsGbmScreen::cursor() const
{
    QKmsScreenConfig *config = device()->screenConfig();
    if (config->hwCursor()) {
        if (!config->separateScreens())
            return static_cast<QEglFSKmsGbmDevice *>(device())->globalCursor();

        if (m_cursor.isNull()) {
            QEglFSKmsGbmScreen *that = const_cast<QEglFSKmsGbmScreen *>(this);
            that->m_cursor.reset(new QEglFSKmsGbmCursor(that));
        }

        return m_cursor.data();
    } else {
        return QEglFSScreen::cursor();
    }
}

gbm_surface *QEglFSKmsGbmScreen::createSurface()
{
    if (!m_gbm_surface) {
        uint32_t gbmFormat = drmFormatToGbmFormat(m_output.drm_format);
        qCDebug(qLcEglfsKmsDebug, "Creating gbm_surface for screen %s with format 0x%x", qPrintable(name()), gbmFormat);
        m_gbm_surface = gbm_surface_create(static_cast<QEglFSKmsGbmDevice *>(device())->gbmDevice(),
                                           rawGeometry().width(),
                                           rawGeometry().height(),
                                           gbmFormat,
                                           GBM_BO_USE_SCANOUT | GBM_BO_USE_RENDERING);
    }
    return m_gbm_surface; // not owned, gets destroyed in QEglFSKmsGbmIntegration::destroyNativeWindow() via QEglFSKmsGbmWindow::invalidateSurface()
}

void QEglFSKmsGbmScreen::resetSurface()
{
    m_gbm_surface = nullptr;
}

void QEglFSKmsGbmScreen::initCloning(QPlatformScreen *screenThisScreenClones,
                                     const QVector<QPlatformScreen *> &screensCloningThisScreen)
{
    // clone destinations need to know the clone source
    const bool clonesAnother = screenThisScreenClones != nullptr;
    if (clonesAnother && !screensCloningThisScreen.isEmpty()) {
        qWarning("QEglFSKmsGbmScreen %s cannot be clone source and destination at the same time", qPrintable(name()));
        return;
    }
    if (clonesAnother)
        m_cloneSource = static_cast<QEglFSKmsGbmScreen *>(screenThisScreenClones);

    // clone sources need to know their additional destinations
    for (QPlatformScreen *s : screensCloningThisScreen) {
        CloneDestination d;
        d.screen = static_cast<QEglFSKmsGbmScreen *>(s);
        m_cloneDests.append(d);
    }
}

void QEglFSKmsGbmScreen::ensureModeSet(uint32_t fb)
{
    QKmsOutput &op(output());
    const int fd = device()->fd();
    const uint32_t w = op.modes[op.mode].hdisplay;
    const uint32_t h = op.modes[op.mode].vdisplay;

    if (!op.mode_set) {
        op.mode_set = true;

        bool doModeSet = true;
        drmModeCrtcPtr currentMode = drmModeGetCrtc(fd, op.crtc_id);
        const bool alreadySet = currentMode && !memcmp(&currentMode->mode, &op.modes[op.mode], sizeof(drmModeModeInfo));
        if (currentMode)
            drmModeFreeCrtc(currentMode);
        if (alreadySet) {
            static bool alwaysDoSet = qEnvironmentVariableIntValue("QT_QPA_EGLFS_ALWAYS_SET_MODE");
            if (!alwaysDoSet) {
                qCDebug(qLcEglfsKmsDebug, "Mode already set, skipping modesetting for screen %s", qPrintable(name()));
                doModeSet = false;
            }
        }

        if (doModeSet) {
            qCDebug(qLcEglfsKmsDebug, "Setting mode for screen %s", qPrintable(name()));
            int ret = drmModeSetCrtc(fd,
                                     op.crtc_id,
                                     fb,
                                     0, 0,
                                     &op.connector_id, 1,
                                     &op.modes[op.mode]);

            if (ret == 0)
                setPowerState(PowerStateOn);
            else
                qErrnoWarning(errno, "Could not set DRM mode for screen %s", qPrintable(name()));
        }
    }

    if (!op.plane_set) {
        op.plane_set = true;
        if (op.wants_plane) {
            qCDebug(qLcEglfsKmsDebug, "Setting plane %u", op.plane_id);
            int ret = drmModeSetPlane(fd, op.plane_id, op.crtc_id,
                                      uint32_t(-1), 0,
                                      0, 0, w, h,
                                      0 << 16, 0 << 16, w << 16, h << 16);
            if (ret)
                qErrnoWarning(errno, "drmModeSetPlane failed");
        }
    }
}

void QEglFSKmsGbmScreen::waitForFlip()
{
    if (m_cloneSource) {
        qWarning("Screen %s clones another screen. swapBuffers() not allowed.", qPrintable(name()));
        return;
    }

    // Don't lock the mutex unless we actually need to
    if (!m_gbm_bo_next)
        return;

    QMutexLocker lock(&m_waitForFlipMutex);
    while (m_gbm_bo_next)
        static_cast<QEglFSKmsGbmDevice *>(device())->handleDrmEvent();
}

void QEglFSKmsGbmScreen::flip()
{
    if (m_cloneSource) {
        qWarning("Screen %s clones another screen. swapBuffers() not allowed.", qPrintable(name()));
        return;
    }

    if (!m_gbm_surface) {
        qWarning("Cannot sync before platform init!");
        return;
    }

    m_gbm_bo_next = gbm_surface_lock_front_buffer(m_gbm_surface);
    if (!m_gbm_bo_next) {
        qWarning("Could not lock GBM surface front buffer!");
        return;
    }

    FrameBuffer *fb = framebufferForBufferObject(m_gbm_bo_next);
    ensureModeSet(fb->fb);

    QKmsOutput &op(output());
    const int fd = device()->fd();
    m_flipPending = true;
    int ret = drmModePageFlip(fd,
                              op.crtc_id,
                              fb->fb,
                              DRM_MODE_PAGE_FLIP_EVENT,
                              this);
    if (ret) {
        qErrnoWarning("Could not queue DRM page flip on screen %s", qPrintable(name()));
        m_flipPending = false;
        gbm_surface_release_buffer(m_gbm_surface, m_gbm_bo_next);
        m_gbm_bo_next = Q_NULLPTR;
        return;
    }

    for (CloneDestination &d : m_cloneDests) {
        if (d.screen != this) {
            d.screen->ensureModeSet(fb->fb);
            d.cloneFlipPending = true;
            int ret = drmModePageFlip(fd,
                                      d.screen->output().crtc_id,
                                      fb->fb,
                                      DRM_MODE_PAGE_FLIP_EVENT,
                                      d.screen);
            if (ret) {
                qErrnoWarning("Could not queue DRM page flip for clone screen %s", qPrintable(name()));
                d.cloneFlipPending = false;
            }
        }
    }
}

void QEglFSKmsGbmScreen::flipFinished()
{
    if (m_cloneSource) {
        m_cloneSource->cloneDestFlipFinished(this);
        return;
    }

    m_flipPending = false;
    updateFlipStatus();
}

void QEglFSKmsGbmScreen::cloneDestFlipFinished(QEglFSKmsGbmScreen *cloneDestScreen)
{
    for (CloneDestination &d : m_cloneDests) {
        if (d.screen == cloneDestScreen) {
            d.cloneFlipPending = false;
            break;
        }
    }
    updateFlipStatus();
}

void QEglFSKmsGbmScreen::updateFlipStatus()
{
    Q_ASSERT(!m_cloneSource);

    if (m_flipPending)
        return;

    for (const CloneDestination &d : m_cloneDests) {
        if (d.cloneFlipPending)
            return;
    }

    if (m_gbm_bo_current)
        gbm_surface_release_buffer(m_gbm_surface,
                                   m_gbm_bo_current);

    m_gbm_bo_current = m_gbm_bo_next;
    m_gbm_bo_next = Q_NULLPTR;
}

QT_END_NAMESPACE