/*
 * Copyright © 2014 Intel Corporation
 * Copyright © 2015 Advanced Micro Devices, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "radeon.h"

#ifdef HAVE_PRESENT_H

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
#include <poll.h>
#include <sys/time.h>
#include <time.h>
#include <errno.h>

#include "radeon_bo_helper.h"
#include "radeon_glamor.h"
#include "radeon_video.h"

#include "present.h"

static present_screen_info_rec radeon_present_screen_info;

struct radeon_present_vblank_event {
    uint64_t event_id;
    Bool vblank_for_flip;
    Bool unflip;
};

static RRCrtcPtr
radeon_present_get_crtc(WindowPtr window)
{
    ScreenPtr screen = window->drawable.pScreen;
    ScrnInfoPtr pScrn = xf86ScreenToScrn(screen);
    xf86CrtcPtr crtc;
    RRCrtcPtr randr_crtc = NULL;

    crtc = radeon_pick_best_crtc(pScrn, FALSE,
				 window->drawable.x,
				 window->drawable.x + window->drawable.width,
				 window->drawable.y,
				 window->drawable.y + window->drawable.height);

    if (crtc)
	randr_crtc = crtc->randr_crtc;

    return randr_crtc;
}

static int
radeon_present_get_ust_msc(RRCrtcPtr crtc, CARD64 *ust, CARD64 *msc)
{
    xf86CrtcPtr xf86_crtc = crtc->devPrivate;
    drmmode_crtc_private_ptr drmmode_crtc = xf86_crtc->driver_private;

    if (drmmode_crtc->dpms_mode != DPMSModeOn)
	return BadAlloc;

    return drmmode_crtc_get_ust_msc(xf86_crtc, ust, msc);
}

/*
 * Flush the DRM event queue when full; this
 * makes space for new requests
 */
static Bool
radeon_present_flush_drm_events(ScreenPtr screen)
{
    ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
    RADEONEntPtr pRADEONEnt = RADEONEntPriv(scrn);
    xf86CrtcConfigPtr xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
    drmmode_crtc_private_ptr drmmode_crtc = xf86_config->crtc[0]->driver_private;
    drmmode_ptr drmmode = drmmode_crtc->drmmode;
    struct pollfd p = { .fd = pRADEONEnt->fd, .events = POLLIN };
    int r;

    do {
	r = poll(&p, 1, 0);
    } while (r == -1 && (errno == EINTR || errno == EAGAIN));

    if (r <= 0)
	return 0;

    return drmHandleEvent(pRADEONEnt->fd, &drmmode->event_context) >= 0;
}

/*
 * Called when the queued vblank event has occurred
 */
static void
radeon_present_vblank_handler(xf86CrtcPtr crtc, unsigned int msc,
			      uint64_t usec, void *data)
{
    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
    struct radeon_present_vblank_event *event = data;

    if (event->vblank_for_flip &&
	drmmode_crtc->tear_free &&
	drmmode_crtc->scanout_update_pending) {
	if (drmmode_crtc->present_vblank_event_id != 0) {
	    xf86DrvMsg(crtc->scrn->scrnIndex, X_WARNING,
		       "Need to handle previously deferred vblank event\n");
	    present_event_notify(drmmode_crtc->present_vblank_event_id,
				 drmmode_crtc->present_vblank_usec,
				 drmmode_crtc->present_vblank_msc);
	}

	drmmode_crtc->present_vblank_event_id = event->event_id;
	drmmode_crtc->present_vblank_msc = msc;
	drmmode_crtc->present_vblank_usec = usec;
    } else
	present_event_notify(event->event_id, usec, msc);

    free(event);
}

/*
 * Called when the queued vblank is aborted
 */
static void
radeon_present_vblank_abort(xf86CrtcPtr crtc, void *data)
{
    struct radeon_present_vblank_event *event = data;

    free(event);
}

/*
 * Queue an event to report back to the Present extension when the specified
 * MSC has past
 */
static int
radeon_present_queue_vblank(RRCrtcPtr crtc, uint64_t event_id, uint64_t msc)
{
    xf86CrtcPtr xf86_crtc = crtc->devPrivate;
    drmmode_crtc_private_ptr drmmode_crtc = xf86_crtc->driver_private;
    ScreenPtr screen = crtc->pScreen;
    struct radeon_present_vblank_event *event;
    uintptr_t drm_queue_seq;

    event = calloc(sizeof(struct radeon_present_vblank_event), 1);
    if (!event)
	return BadAlloc;
    event->event_id = event_id;
    event->vblank_for_flip = drmmode_crtc->present_flip_expected;
    drmmode_crtc->present_flip_expected = FALSE;

    drm_queue_seq = radeon_drm_queue_alloc(xf86_crtc,
					   RADEON_DRM_QUEUE_CLIENT_DEFAULT,
					   event_id, event,
					   radeon_present_vblank_handler,
					   radeon_present_vblank_abort);
    if (drm_queue_seq == RADEON_DRM_QUEUE_ERROR) {
	free(event);
	return BadAlloc;
    }

    for (;;) {
	if (drmmode_wait_vblank(xf86_crtc,
				DRM_VBLANK_ABSOLUTE | DRM_VBLANK_EVENT, msc,
				drm_queue_seq, NULL, NULL))
	    break;
	if (errno != EBUSY || !radeon_present_flush_drm_events(screen)) {
	    radeon_drm_abort_entry(drm_queue_seq);
	    return BadAlloc;
	}
    }

    return Success;
}

/*
 * Remove a pending vblank event from the DRM queue so that it is not reported
 * to the extension
 */
static void
radeon_present_abort_vblank(RRCrtcPtr crtc, uint64_t event_id, uint64_t msc)
{
    radeon_drm_abort_id(event_id);
}

/*
 * Flush our batch buffer when requested by the Present extension.
 */
static void
radeon_present_flush(WindowPtr window)
{
    radeon_cs_flush_indirect(xf86ScreenToScrn(window->drawable.pScreen));
}

static uint32_t
radeon_present_get_pixmap_tiling_flags(RADEONInfoPtr info, PixmapPtr pixmap)
{
    uint32_t tiling_flags = radeon_get_pixmap_tiling_flags(pixmap);

    /* Micro tiling is always enabled with macro tiling on >= R600, so we
     * can ignore the micro tiling bit in that case
     */
    if ((tiling_flags & RADEON_TILING_MACRO) &&
	info->ChipFamily >= CHIP_FAMILY_R600)
	tiling_flags &= ~RADEON_TILING_MICRO;

    return tiling_flags;
}

/*
 * Test to see if unflipping is possible
 *
 * These tests have to pass for flips as well
 */
static Bool
radeon_present_check_unflip(ScrnInfoPtr scrn)
{
    xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
    int num_crtcs_on;
    int i;

    if (!scrn->vtSema)
	return FALSE;

    for (i = 0, num_crtcs_on = 0; i < config->num_crtc; i++) {
	xf86CrtcPtr crtc = config->crtc[i];

	if (drmmode_crtc_can_flip(crtc)) {
	    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;

	    if (drmmode_crtc->flip_pending)
		return FALSE;

	    if (!drmmode_crtc->tear_free)
		num_crtcs_on++;
	}
    }

    return num_crtcs_on > 0;
}

/*
 * Test to see if page flipping is possible on the target crtc
 */
static Bool
radeon_present_check_flip(RRCrtcPtr crtc, WindowPtr window, PixmapPtr pixmap,
	      Bool sync_flip)
{
    xf86CrtcPtr xf86_crtc = crtc->devPrivate;
    drmmode_crtc_private_ptr drmmode_crtc = xf86_crtc->driver_private;
    ScreenPtr screen = window->drawable.pScreen;
    ScrnInfoPtr scrn = xf86_crtc->scrn;
    xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
    RADEONInfoPtr info = RADEONPTR(scrn);
    PixmapPtr screen_pixmap;
    int num_crtcs_on;
    int i;

    drmmode_crtc->present_flip_expected = FALSE;

    if (!scrn->vtSema)
	return FALSE;

    if (!info->allowPageFlip)
	return FALSE;

    if (info->sprites_visible > 0)
	return FALSE;

    if (info->drmmode.dri2_flipping)
	return FALSE;

    /* The kernel driver doesn't handle flipping between BOs with different
     * tiling parameters correctly yet
     */
    screen_pixmap = screen->GetScreenPixmap(screen);
    if (radeon_present_get_pixmap_tiling_flags(info, pixmap) !=
	radeon_present_get_pixmap_tiling_flags(info, screen_pixmap))
	return FALSE;

    for (i = 0, num_crtcs_on = 0; i < config->num_crtc; i++) {
	if (drmmode_crtc_can_flip(config->crtc[i]))
	    num_crtcs_on++;
	else if (config->crtc[i] == crtc->devPrivate)
	    return FALSE;
    }

    if (num_crtcs_on == 0)
	return FALSE;

    drmmode_crtc->present_flip_expected = TRUE;
    return TRUE;
}

/*
 * Once the flip has been completed on all CRTCs, notify the
 * extension code telling it when that happened
 */
static void
radeon_present_flip_event(xf86CrtcPtr crtc, uint32_t msc, uint64_t ust, void *pageflip_data)
{
    RADEONInfoPtr info = RADEONPTR(crtc->scrn);
    struct radeon_present_vblank_event *event = pageflip_data;

    if (event->unflip)
	info->drmmode.present_flipping = FALSE;

    present_event_notify(event->event_id, ust, msc);
    free(event);
}

/*
 * The flip has been aborted, free the structure
 */
static void
radeon_present_flip_abort(xf86CrtcPtr crtc, void *pageflip_data)
{
    struct radeon_present_vblank_event *event = pageflip_data;

    free(event);
}

/*
 * Queue a flip on 'crtc' to 'pixmap' at 'target_msc'. If 'sync_flip' is true,
 * then wait for vblank. Otherwise, flip immediately
 */
static Bool
radeon_present_flip(RRCrtcPtr crtc, uint64_t event_id, uint64_t target_msc,
                   PixmapPtr pixmap, Bool sync_flip)
{
    xf86CrtcPtr xf86_crtc = crtc->devPrivate;
    drmmode_crtc_private_ptr drmmode_crtc = xf86_crtc->driver_private;
    ScreenPtr screen = crtc->pScreen;
    ScrnInfoPtr scrn = xf86_crtc->scrn;
    RADEONInfoPtr info = RADEONPTR(scrn);
    struct radeon_present_vblank_event *event;
    Bool ret = FALSE;

    if (!radeon_present_check_flip(crtc, screen->root, pixmap, sync_flip))
	goto out;

    event = calloc(1, sizeof(struct radeon_present_vblank_event));
    if (!event)
	goto out;

    event->event_id = event_id;

    radeon_cs_flush_indirect(scrn);

    ret = radeon_do_pageflip(scrn, RADEON_DRM_QUEUE_CLIENT_DEFAULT, pixmap,
			     event_id, event, crtc->devPrivate,
			     radeon_present_flip_event,
			     radeon_present_flip_abort,
			     sync_flip ? FLIP_VSYNC : FLIP_ASYNC,
			     target_msc);
    if (!ret)
	xf86DrvMsg(scrn->scrnIndex, X_ERROR, "present flip failed\n");
    else
	info->drmmode.present_flipping = TRUE;

 out:
    drmmode_crtc->present_flip_expected = FALSE;
    return ret;
}

/*
 * Queue a flip back to the normal frame buffer
 */
static void
radeon_present_unflip(ScreenPtr screen, uint64_t event_id)
{
    ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
    RADEONInfoPtr info = RADEONPTR(scrn);
    xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
    struct radeon_present_vblank_event *event;
    PixmapPtr pixmap = screen->GetScreenPixmap(screen);
    enum drmmode_flip_sync flip_sync =
	(radeon_present_screen_info.capabilities & PresentCapabilityAsync) ?
	FLIP_ASYNC : FLIP_VSYNC;
    int i;

    radeon_cs_flush_indirect(scrn);

    if (!radeon_present_check_unflip(scrn))
	goto modeset;

    event = calloc(1, sizeof(struct radeon_present_vblank_event));
    if (!event) {
	ErrorF("%s: calloc failed, display might freeze\n", __func__);
	goto modeset;
    }

    event->event_id = event_id;
    event->unflip = TRUE;

    if (radeon_do_pageflip(scrn, RADEON_DRM_QUEUE_CLIENT_DEFAULT, pixmap,
			   event_id, event, NULL, radeon_present_flip_event,
			   radeon_present_flip_abort, flip_sync, 0))
	return;

modeset:
    radeon_bo_wait(info->front_bo);
    for (i = 0; i < config->num_crtc; i++) {
	xf86CrtcPtr crtc = config->crtc[i];
	drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;

	if (!crtc->enabled || drmmode_crtc->tear_free)
	    continue;

	if (drmmode_crtc->dpms_mode == DPMSModeOn)
	    crtc->funcs->set_mode_major(crtc, &crtc->mode, crtc->rotation,
					crtc->x, crtc->y);
	else
	    drmmode_crtc->need_modeset = TRUE;
    }

    present_event_notify(event_id, 0, 0);

    info->drmmode.present_flipping = FALSE;
}

static present_screen_info_rec radeon_present_screen_info = {
    .version = 0,

    .get_crtc = radeon_present_get_crtc,
    .get_ust_msc = radeon_present_get_ust_msc,
    .queue_vblank = radeon_present_queue_vblank,
    .abort_vblank = radeon_present_abort_vblank,
    .flush = radeon_present_flush,

    .capabilities = PresentCapabilityNone,
    .check_flip = radeon_present_check_flip,
    .flip = radeon_present_flip,
    .unflip = radeon_present_unflip,
};

static Bool
radeon_present_has_async_flip(ScreenPtr screen)
{
#ifdef DRM_CAP_ASYNC_PAGE_FLIP
    ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
    RADEONEntPtr pRADEONEnt = RADEONEntPriv(scrn);
    int ret;
    uint64_t value;

    ret = drmGetCap(pRADEONEnt->fd, DRM_CAP_ASYNC_PAGE_FLIP, &value);
    if (ret == 0)
	return value == 1;
#endif
    return FALSE;
}

Bool
radeon_present_screen_init(ScreenPtr screen)
{
    if (radeon_present_has_async_flip(screen))
	radeon_present_screen_info.capabilities |= PresentCapabilityAsync;

    if (!present_screen_init(screen, &radeon_present_screen_info)) {
	xf86DrvMsg(xf86ScreenToScrn(screen)->scrnIndex, X_WARNING,
		   "Present extension disabled because present_screen_init failed\n");
	return FALSE;
    }

    xf86DrvMsg(xf86ScreenToScrn(screen)->scrnIndex, X_INFO,
	       "Present extension enabled\n");

    return TRUE;
}

#else /* !HAVE_PRESENT_H */

Bool
radeon_present_screen_init(ScreenPtr screen)
{
    xf86DrvMsg(xf86ScreenToScrn(screen)->scrnIndex, X_INFO,
	       "Present extension disabled because present.h not available at "
	       "build time\n");

    return FALSE;
}

#endif