/*
 * Copyright 2007-8 Advanced Micro Devices, Inc.
 * Copyright 2008 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Dave Airlie
 *          Alex Deucher
 */
#include <drm/drmP.h>
#include <drm/radeon_drm.h>
#include "radeon.h"

#include "atom.h"
#include <asm/div64.h>

#include <linux/pm_runtime.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_edid.h>

#include <linux/gcd.h>

static void avivo_crtc_load_lut(struct drm_crtc *crtc)
{
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        u16 *r, *g, *b;
        int i;

        DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
        WREG32(AVIVO_DC_LUTA_CONTROL + radeon_crtc->crtc_offset, 0);

        WREG32(AVIVO_DC_LUTA_BLACK_OFFSET_BLUE + radeon_crtc->crtc_offset, 0);
        WREG32(AVIVO_DC_LUTA_BLACK_OFFSET_GREEN + radeon_crtc->crtc_offset, 0);
        WREG32(AVIVO_DC_LUTA_BLACK_OFFSET_RED + radeon_crtc->crtc_offset, 0);

        WREG32(AVIVO_DC_LUTA_WHITE_OFFSET_BLUE + radeon_crtc->crtc_offset, 0xffff);
        WREG32(AVIVO_DC_LUTA_WHITE_OFFSET_GREEN + radeon_crtc->crtc_offset, 0xffff);
        WREG32(AVIVO_DC_LUTA_WHITE_OFFSET_RED + radeon_crtc->crtc_offset, 0xffff);

        WREG32(AVIVO_DC_LUT_RW_SELECT, radeon_crtc->crtc_id);
        WREG32(AVIVO_DC_LUT_RW_MODE, 0);
        WREG32(AVIVO_DC_LUT_WRITE_EN_MASK, 0x0000003f);

        WREG8(AVIVO_DC_LUT_RW_INDEX, 0);
        r = crtc->gamma_store;
        g = r + crtc->gamma_size;
        b = g + crtc->gamma_size;
        for (i = 0; i < 256; i++) {
                WREG32(AVIVO_DC_LUT_30_COLOR,
                       ((*r++ & 0xffc0) << 14) |
                       ((*g++ & 0xffc0) << 4) |
                       (*b++ >> 6));
        }

        /* Only change bit 0 of LUT_SEL, other bits are set elsewhere */
        WREG32_P(AVIVO_D1GRPH_LUT_SEL + radeon_crtc->crtc_offset, radeon_crtc->crtc_id, ~1);
}

static void dce4_crtc_load_lut(struct drm_crtc *crtc)
{
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        u16 *r, *g, *b;
        int i;

        DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
        WREG32(EVERGREEN_DC_LUT_CONTROL + radeon_crtc->crtc_offset, 0);

        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_BLUE + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_GREEN + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_RED + radeon_crtc->crtc_offset, 0);

        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_BLUE + radeon_crtc->crtc_offset, 0xffff);
        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_GREEN + radeon_crtc->crtc_offset, 0xffff);
        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_RED + radeon_crtc->crtc_offset, 0xffff);

        WREG32(EVERGREEN_DC_LUT_RW_MODE + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_WRITE_EN_MASK + radeon_crtc->crtc_offset, 0x00000007);

        WREG32(EVERGREEN_DC_LUT_RW_INDEX + radeon_crtc->crtc_offset, 0);
        r = crtc->gamma_store;
        g = r + crtc->gamma_size;
        b = g + crtc->gamma_size;
        for (i = 0; i < 256; i++) {
                WREG32(EVERGREEN_DC_LUT_30_COLOR + radeon_crtc->crtc_offset,
                       ((*r++ & 0xffc0) << 14) |
                       ((*g++ & 0xffc0) << 4) |
                       (*b++ >> 6));
        }
}

static void dce5_crtc_load_lut(struct drm_crtc *crtc)
{
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        u16 *r, *g, *b;
        int i;

        DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);

        WREG32(NI_INPUT_CSC_CONTROL + radeon_crtc->crtc_offset,
               (NI_INPUT_CSC_GRPH_MODE(NI_INPUT_CSC_BYPASS) |
                NI_INPUT_CSC_OVL_MODE(NI_INPUT_CSC_BYPASS)));
        WREG32(NI_PRESCALE_GRPH_CONTROL + radeon_crtc->crtc_offset,
               NI_GRPH_PRESCALE_BYPASS);
        WREG32(NI_PRESCALE_OVL_CONTROL + radeon_crtc->crtc_offset,
               NI_OVL_PRESCALE_BYPASS);
        WREG32(NI_INPUT_GAMMA_CONTROL + radeon_crtc->crtc_offset,
               (NI_GRPH_INPUT_GAMMA_MODE(NI_INPUT_GAMMA_USE_LUT) |
                NI_OVL_INPUT_GAMMA_MODE(NI_INPUT_GAMMA_USE_LUT)));

        WREG32(EVERGREEN_DC_LUT_CONTROL + radeon_crtc->crtc_offset, 0);

        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_BLUE + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_GREEN + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_BLACK_OFFSET_RED + radeon_crtc->crtc_offset, 0);

        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_BLUE + radeon_crtc->crtc_offset, 0xffff);
        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_GREEN + radeon_crtc->crtc_offset, 0xffff);
        WREG32(EVERGREEN_DC_LUT_WHITE_OFFSET_RED + radeon_crtc->crtc_offset, 0xffff);

        WREG32(EVERGREEN_DC_LUT_RW_MODE + radeon_crtc->crtc_offset, 0);
        WREG32(EVERGREEN_DC_LUT_WRITE_EN_MASK + radeon_crtc->crtc_offset, 0x00000007);

        WREG32(EVERGREEN_DC_LUT_RW_INDEX + radeon_crtc->crtc_offset, 0);
        r = crtc->gamma_store;
        g = r + crtc->gamma_size;
        b = g + crtc->gamma_size;
        for (i = 0; i < 256; i++) {
                WREG32(EVERGREEN_DC_LUT_30_COLOR + radeon_crtc->crtc_offset,
                       ((*r++ & 0xffc0) << 14) |
                       ((*g++ & 0xffc0) << 4) |
                       (*b++ >> 6));
        }

        WREG32(NI_DEGAMMA_CONTROL + radeon_crtc->crtc_offset,
               (NI_GRPH_DEGAMMA_MODE(NI_DEGAMMA_BYPASS) |
                NI_OVL_DEGAMMA_MODE(NI_DEGAMMA_BYPASS) |
                NI_ICON_DEGAMMA_MODE(NI_DEGAMMA_BYPASS) |
                NI_CURSOR_DEGAMMA_MODE(NI_DEGAMMA_BYPASS)));
        WREG32(NI_GAMUT_REMAP_CONTROL + radeon_crtc->crtc_offset,
               (NI_GRPH_GAMUT_REMAP_MODE(NI_GAMUT_REMAP_BYPASS) |
                NI_OVL_GAMUT_REMAP_MODE(NI_GAMUT_REMAP_BYPASS)));
        WREG32(NI_REGAMMA_CONTROL + radeon_crtc->crtc_offset,
               (NI_GRPH_REGAMMA_MODE(NI_REGAMMA_BYPASS) |
                NI_OVL_REGAMMA_MODE(NI_REGAMMA_BYPASS)));
        WREG32(NI_OUTPUT_CSC_CONTROL + radeon_crtc->crtc_offset,
               (NI_OUTPUT_CSC_GRPH_MODE(radeon_crtc->output_csc) |
                NI_OUTPUT_CSC_OVL_MODE(NI_OUTPUT_CSC_BYPASS)));
        /* XXX match this to the depth of the crtc fmt block, move to modeset? */
        WREG32(0x6940 + radeon_crtc->crtc_offset, 0);
        if (ASIC_IS_DCE8(rdev)) {
                /* XXX this only needs to be programmed once per crtc at startup,
                 * not sure where the best place for it is
                 */
                WREG32(CIK_ALPHA_CONTROL + radeon_crtc->crtc_offset,
                       CIK_CURSOR_ALPHA_BLND_ENA);
        }
}

static void legacy_crtc_load_lut(struct drm_crtc *crtc)
{
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        u16 *r, *g, *b;
        int i;
        uint32_t dac2_cntl;

        dac2_cntl = RREG32(RADEON_DAC_CNTL2);
        if (radeon_crtc->crtc_id == 0)
                dac2_cntl &= (uint32_t)~RADEON_DAC2_PALETTE_ACC_CTL;
        else
                dac2_cntl |= RADEON_DAC2_PALETTE_ACC_CTL;
        WREG32(RADEON_DAC_CNTL2, dac2_cntl);

        WREG8(RADEON_PALETTE_INDEX, 0);
        r = crtc->gamma_store;
        g = r + crtc->gamma_size;
        b = g + crtc->gamma_size;
        for (i = 0; i < 256; i++) {
                WREG32(RADEON_PALETTE_30_DATA,
                       ((*r++ & 0xffc0) << 14) |
                       ((*g++ & 0xffc0) << 4) |
                       (*b++ >> 6));
        }
}

void radeon_crtc_load_lut(struct drm_crtc *crtc)
{
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;

        if (!crtc->enabled)
                return;

        if (ASIC_IS_DCE5(rdev))
                dce5_crtc_load_lut(crtc);
        else if (ASIC_IS_DCE4(rdev))
                dce4_crtc_load_lut(crtc);
        else if (ASIC_IS_AVIVO(rdev))
                avivo_crtc_load_lut(crtc);
        else
                legacy_crtc_load_lut(crtc);
}

static int radeon_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
                                 u16 *blue, uint32_t size,
                                 struct drm_modeset_acquire_ctx *ctx)
{
        radeon_crtc_load_lut(crtc);

        return 0;
}

static void radeon_crtc_destroy(struct drm_crtc *crtc)
{
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);

        drm_crtc_cleanup(crtc);
        destroy_workqueue(radeon_crtc->flip_queue);
        kfree(radeon_crtc);
}

/**
 * radeon_unpin_work_func - unpin old buffer object
 *
 * @__work - kernel work item
 *
 * Unpin the old frame buffer object outside of the interrupt handler
 */
static void radeon_unpin_work_func(struct work_struct *__work)
{
        struct radeon_flip_work *work =
                container_of(__work, struct radeon_flip_work, unpin_work);
        int r;

        /* unpin of the old buffer */
        r = radeon_bo_reserve(work->old_rbo, false);
        if (likely(r == 0)) {
                r = radeon_bo_unpin(work->old_rbo);
                if (unlikely(r != 0)) {
                        DRM_ERROR("failed to unpin buffer after flip\n");
                }
                radeon_bo_unreserve(work->old_rbo);
        } else
                DRM_ERROR("failed to reserve buffer after flip\n");

        drm_gem_object_put_unlocked(&work->old_rbo->gem_base);
        kfree(work);
}

void radeon_crtc_handle_vblank(struct radeon_device *rdev, int crtc_id)
{
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        unsigned long flags;
        u32 update_pending;
        int vpos, hpos;

        /* can happen during initialization */
        if (radeon_crtc == NULL)
                return;

        /* Skip the pageflip completion check below (based on polling) on
         * asics which reliably support hw pageflip completion irqs. pflip
         * irqs are a reliable and race-free method of handling pageflip
         * completion detection. A use_pflipirq module parameter < 2 allows
         * to override this in case of asics with faulty pflip irqs.
         * A module parameter of 0 would only use this polling based path,
         * a parameter of 1 would use pflip irq only as a backup to this
         * path, as in Linux 3.16.
         */
        if ((radeon_use_pflipirq == 2) && ASIC_IS_DCE4(rdev))
                return;

        spin_lock_irqsave(&rdev->ddev->event_lock, flags);
        if (radeon_crtc->flip_status != RADEON_FLIP_SUBMITTED) {
                DRM_DEBUG_DRIVER("radeon_crtc->flip_status = %d != "
                                 "RADEON_FLIP_SUBMITTED(%d)\n",
                                 radeon_crtc->flip_status,
                                 RADEON_FLIP_SUBMITTED);
                spin_unlock_irqrestore(&rdev->ddev->event_lock, flags);
                return;
        }

        update_pending = radeon_page_flip_pending(rdev, crtc_id);

        /* Has the pageflip already completed in crtc, or is it certain
         * to complete in this vblank? GET_DISTANCE_TO_VBLANKSTART provides
         * distance to start of "fudged earlier" vblank in vpos, distance to
         * start of real vblank in hpos. vpos >= 0 && hpos < 0 means we are in
         * the last few scanlines before start of real vblank, where the vblank
         * irq can fire, so we have sampled update_pending a bit too early and
         * know the flip will complete at leading edge of the upcoming real
         * vblank. On pre-AVIVO hardware, flips also complete inside the real
         * vblank, not only at leading edge, so if update_pending for hpos >= 0
         *  == inside real vblank, the flip will complete almost immediately.
         * Note that this method of completion handling is still not 100% race
         * free, as we could execute before the radeon_flip_work_func managed
         * to run and set the RADEON_FLIP_SUBMITTED status, thereby we no-op,
         * but the flip still gets programmed into hw and completed during
         * vblank, leading to a delayed emission of the flip completion event.
         * This applies at least to pre-AVIVO hardware, where flips are always
         * completing inside vblank, not only at leading edge of vblank.
         */
        if (update_pending &&
            (DRM_SCANOUTPOS_VALID &
             radeon_get_crtc_scanoutpos(rdev->ddev, crtc_id,
                                        GET_DISTANCE_TO_VBLANKSTART,
                                        &vpos, &hpos, NULL, NULL,
                                        &rdev->mode_info.crtcs[crtc_id]->base.hwmode)) &&
            ((vpos >= 0 && hpos < 0) || (hpos >= 0 && !ASIC_IS_AVIVO(rdev)))) {
                /* crtc didn't flip in this target vblank interval,
                 * but flip is pending in crtc. Based on the current
                 * scanout position we know that the current frame is
                 * (nearly) complete and the flip will (likely)
                 * complete before the start of the next frame.
                 */
                update_pending = 0;
        }
        spin_unlock_irqrestore(&rdev->ddev->event_lock, flags);
        if (!update_pending)
                radeon_crtc_handle_flip(rdev, crtc_id);
}

/**
 * radeon_crtc_handle_flip - page flip completed
 *
 * @rdev: radeon device pointer
 * @crtc_id: crtc number this event is for
 *
 * Called when we are sure that a page flip for this crtc is completed.
 */
void radeon_crtc_handle_flip(struct radeon_device *rdev, int crtc_id)
{
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        struct radeon_flip_work *work;
        unsigned long flags;

        /* this can happen at init */
        if (radeon_crtc == NULL)
                return;

        spin_lock_irqsave(&rdev->ddev->event_lock, flags);
        work = radeon_crtc->flip_work;
        if (radeon_crtc->flip_status != RADEON_FLIP_SUBMITTED) {
                DRM_DEBUG_DRIVER("radeon_crtc->flip_status = %d != "
                                 "RADEON_FLIP_SUBMITTED(%d)\n",
                                 radeon_crtc->flip_status,
                                 RADEON_FLIP_SUBMITTED);
                spin_unlock_irqrestore(&rdev->ddev->event_lock, flags);
                return;
        }

        /* Pageflip completed. Clean up. */
        radeon_crtc->flip_status = RADEON_FLIP_NONE;
        radeon_crtc->flip_work = NULL;

        /* wakeup userspace */
        if (work->event)
                drm_crtc_send_vblank_event(&radeon_crtc->base, work->event);

        spin_unlock_irqrestore(&rdev->ddev->event_lock, flags);

        drm_crtc_vblank_put(&radeon_crtc->base);
        radeon_irq_kms_pflip_irq_put(rdev, work->crtc_id);
        queue_work(radeon_crtc->flip_queue, &work->unpin_work);
}

/**
 * radeon_flip_work_func - page flip framebuffer
 *
 * @work - kernel work item
 *
 * Wait for the buffer object to become idle and do the actual page flip
 */
static void radeon_flip_work_func(struct work_struct *__work)
{
        struct radeon_flip_work *work =
                container_of(__work, struct radeon_flip_work, flip_work);
        struct radeon_device *rdev = work->rdev;
        struct drm_device *dev = rdev->ddev;
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[work->crtc_id];

        struct drm_crtc *crtc = &radeon_crtc->base;
        unsigned long flags;
        int r;
        int vpos, hpos;

        down_read(&rdev->exclusive_lock);
        if (work->fence) {
                struct radeon_fence *fence;

                fence = to_radeon_fence(work->fence);
                if (fence && fence->rdev == rdev) {
                        r = radeon_fence_wait(fence, false);
                        if (r == -EDEADLK) {
                                up_read(&rdev->exclusive_lock);
                                do {
                                        r = radeon_gpu_reset(rdev);
                                } while (r == -EAGAIN);
                                down_read(&rdev->exclusive_lock);
                        }
                } else
                        r = dma_fence_wait(work->fence, false);

                if (r)
                        DRM_ERROR("failed to wait on page flip fence (%d)!\n", r);

                /* We continue with the page flip even if we failed to wait on
                 * the fence, otherwise the DRM core and userspace will be
                 * confused about which BO the CRTC is scanning out
                 */

                dma_fence_put(work->fence);
                work->fence = NULL;
        }

        /* Wait until we're out of the vertical blank period before the one
         * targeted by the flip. Always wait on pre DCE4 to avoid races with
         * flip completion handling from vblank irq, as these old asics don't
         * have reliable pageflip completion interrupts.
         */
        while (radeon_crtc->enabled &&
                (radeon_get_crtc_scanoutpos(dev, work->crtc_id, 0,
                                            &vpos, &hpos, NULL, NULL,
                                            &crtc->hwmode)
                & (DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_IN_VBLANK)) ==
                (DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_IN_VBLANK) &&
                (!ASIC_IS_AVIVO(rdev) ||
                ((int) (work->target_vblank -
                dev->driver->get_vblank_counter(dev, work->crtc_id)) > 0)))
                usleep_range(1000, 2000);

        /* We borrow the event spin lock for protecting flip_status */
        spin_lock_irqsave(&crtc->dev->event_lock, flags);

        /* set the proper interrupt */
        radeon_irq_kms_pflip_irq_get(rdev, radeon_crtc->crtc_id);

        /* do the flip (mmio) */
        radeon_page_flip(rdev, radeon_crtc->crtc_id, work->base, work->async);

        radeon_crtc->flip_status = RADEON_FLIP_SUBMITTED;
        spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
        up_read(&rdev->exclusive_lock);
}

static int radeon_crtc_page_flip_target(struct drm_crtc *crtc,
                                        struct drm_framebuffer *fb,
                                        struct drm_pending_vblank_event *event,
                                        uint32_t page_flip_flags,
                                        uint32_t target,
                                        struct drm_modeset_acquire_ctx *ctx)
{
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct drm_gem_object *obj;
        struct radeon_flip_work *work;
        struct radeon_bo *new_rbo;
        uint32_t tiling_flags, pitch_pixels;
        uint64_t base;
        unsigned long flags;
        int r;

        work = kzalloc(sizeof *work, GFP_KERNEL);
        if (work == NULL)
                return -ENOMEM;

        INIT_WORK(&work->flip_work, radeon_flip_work_func);
        INIT_WORK(&work->unpin_work, radeon_unpin_work_func);

        work->rdev = rdev;
        work->crtc_id = radeon_crtc->crtc_id;
        work->event = event;
        work->async = (page_flip_flags & DRM_MODE_PAGE_FLIP_ASYNC) != 0;

        /* schedule unpin of the old buffer */
        obj = crtc->primary->fb->obj[0];

        /* take a reference to the old object */
        drm_gem_object_get(obj);
        work->old_rbo = gem_to_radeon_bo(obj);

        obj = fb->obj[0];
        new_rbo = gem_to_radeon_bo(obj);

        /* pin the new buffer */
        DRM_DEBUG_DRIVER("flip-ioctl() cur_rbo = %p, new_rbo = %p\n",
                         work->old_rbo, new_rbo);

        r = radeon_bo_reserve(new_rbo, false);
        if (unlikely(r != 0)) {
                DRM_ERROR("failed to reserve new rbo buffer before flip\n");
                goto cleanup;
        }
        /* Only 27 bit offset for legacy CRTC */
        r = radeon_bo_pin_restricted(new_rbo, RADEON_GEM_DOMAIN_VRAM,
                                     ASIC_IS_AVIVO(rdev) ? 0 : 1 << 27, &base);
        if (unlikely(r != 0)) {
                radeon_bo_unreserve(new_rbo);
                r = -EINVAL;
                DRM_ERROR("failed to pin new rbo buffer before flip\n");
                goto cleanup;
        }
        work->fence = dma_fence_get(reservation_object_get_excl(new_rbo->tbo.resv));
        radeon_bo_get_tiling_flags(new_rbo, &tiling_flags, NULL);
        radeon_bo_unreserve(new_rbo);

        if (!ASIC_IS_AVIVO(rdev)) {
                /* crtc offset is from display base addr not FB location */
                base -= radeon_crtc->legacy_display_base_addr;
                pitch_pixels = fb->pitches[0] / fb->format->cpp[0];

                if (tiling_flags & RADEON_TILING_MACRO) {
                        if (ASIC_IS_R300(rdev)) {
                                base &= ~0x7ff;
                        } else {
                                int byteshift = fb->format->cpp[0] * 8 >> 4;
                                int tile_addr = (((crtc->y >> 3) * pitch_pixels +  crtc->x) >> (8 - byteshift)) << 11;
                                base += tile_addr + ((crtc->x << byteshift) % 256) + ((crtc->y % 8) << 8);
                        }
                } else {
                        int offset = crtc->y * pitch_pixels + crtc->x;
                        switch (fb->format->cpp[0] * 8) {
                        case 8:
                        default:
                                offset *= 1;
                                break;
                        case 15:
                        case 16:
                                offset *= 2;
                                break;
                        case 24:
                                offset *= 3;
                                break;
                        case 32:
                                offset *= 4;
                                break;
                        }
                        base += offset;
                }
                base &= ~7;
        }
        work->base = base;
        work->target_vblank = target - (uint32_t)drm_crtc_vblank_count(crtc) +
                dev->driver->get_vblank_counter(dev, work->crtc_id);

        /* We borrow the event spin lock for protecting flip_work */
        spin_lock_irqsave(&crtc->dev->event_lock, flags);

        if (radeon_crtc->flip_status != RADEON_FLIP_NONE) {
                DRM_DEBUG_DRIVER("flip queue: crtc already busy\n");
                spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
                r = -EBUSY;
                goto pflip_cleanup;
        }
        radeon_crtc->flip_status = RADEON_FLIP_PENDING;
        radeon_crtc->flip_work = work;

        /* update crtc fb */
        crtc->primary->fb = fb;

        spin_unlock_irqrestore(&crtc->dev->event_lock, flags);

        queue_work(radeon_crtc->flip_queue, &work->flip_work);
        return 0;

pflip_cleanup:
        if (unlikely(radeon_bo_reserve(new_rbo, false) != 0)) {
                DRM_ERROR("failed to reserve new rbo in error path\n");
                goto cleanup;
        }
        if (unlikely(radeon_bo_unpin(new_rbo) != 0)) {
                DRM_ERROR("failed to unpin new rbo in error path\n");
        }
        radeon_bo_unreserve(new_rbo);

cleanup:
        drm_gem_object_put_unlocked(&work->old_rbo->gem_base);
        dma_fence_put(work->fence);
        kfree(work);
        return r;
}

static int
radeon_crtc_set_config(struct drm_mode_set *set,
                       struct drm_modeset_acquire_ctx *ctx)
{
        struct drm_device *dev;
        struct radeon_device *rdev;
        struct drm_crtc *crtc;
        bool active = false;
        int ret;

        if (!set || !set->crtc)
                return -EINVAL;

        dev = set->crtc->dev;

        ret = pm_runtime_get_sync(dev->dev);
        if (ret < 0)
                return ret;

        ret = drm_crtc_helper_set_config(set, ctx);

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                if (crtc->enabled)
                        active = true;

        pm_runtime_mark_last_busy(dev->dev);

        rdev = dev->dev_private;
        /* if we have active crtcs and we don't have a power ref,
           take the current one */
        if (active && !rdev->have_disp_power_ref) {
                rdev->have_disp_power_ref = true;
                return ret;
        }
        /* if we have no active crtcs, then drop the power ref
           we got before */
        if (!active && rdev->have_disp_power_ref) {
                pm_runtime_put_autosuspend(dev->dev);
                rdev->have_disp_power_ref = false;
        }

        /* drop the power reference we got coming in here */
        pm_runtime_put_autosuspend(dev->dev);
        return ret;
}

static const struct drm_crtc_funcs radeon_crtc_funcs = {
        .cursor_set2 = radeon_crtc_cursor_set2,
        .cursor_move = radeon_crtc_cursor_move,
        .gamma_set = radeon_crtc_gamma_set,
        .set_config = radeon_crtc_set_config,
        .destroy = radeon_crtc_destroy,
        .page_flip_target = radeon_crtc_page_flip_target,
};

static void radeon_crtc_init(struct drm_device *dev, int index)
{
        struct radeon_device *rdev = dev->dev_private;
        struct radeon_crtc *radeon_crtc;
        int i;

        radeon_crtc = kzalloc(sizeof(struct radeon_crtc) + (RADEONFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
        if (radeon_crtc == NULL)
                return;

        drm_crtc_init(dev, &radeon_crtc->base, &radeon_crtc_funcs);

        drm_mode_crtc_set_gamma_size(&radeon_crtc->base, 256);
        radeon_crtc->crtc_id = index;
        radeon_crtc->flip_queue = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0);
        rdev->mode_info.crtcs[index] = radeon_crtc;

        if (rdev->family >= CHIP_BONAIRE) {
                radeon_crtc->max_cursor_width = CIK_CURSOR_WIDTH;
                radeon_crtc->max_cursor_height = CIK_CURSOR_HEIGHT;
        } else {
                radeon_crtc->max_cursor_width = CURSOR_WIDTH;
                radeon_crtc->max_cursor_height = CURSOR_HEIGHT;
        }
        dev->mode_config.cursor_width = radeon_crtc->max_cursor_width;
        dev->mode_config.cursor_height = radeon_crtc->max_cursor_height;

#if 0
        radeon_crtc->mode_set.crtc = &radeon_crtc->base;
        radeon_crtc->mode_set.connectors = (struct drm_connector **)(radeon_crtc + 1);
        radeon_crtc->mode_set.num_connectors = 0;
#endif

        for (i = 0; i < 256; i++) {
                radeon_crtc->lut_r[i] = i << 2;
                radeon_crtc->lut_g[i] = i << 2;
                radeon_crtc->lut_b[i] = i << 2;
        }

        if (rdev->is_atom_bios && (ASIC_IS_AVIVO(rdev) || radeon_r4xx_atom))
                radeon_atombios_init_crtc(dev, radeon_crtc);
        else
                radeon_legacy_init_crtc(dev, radeon_crtc);
}

static const char *encoder_names[38] = {
        "NONE",
        "INTERNAL_LVDS",
        "INTERNAL_TMDS1",
        "INTERNAL_TMDS2",
        "INTERNAL_DAC1",
        "INTERNAL_DAC2",
        "INTERNAL_SDVOA",
        "INTERNAL_SDVOB",
        "SI170B",
        "CH7303",
        "CH7301",
        "INTERNAL_DVO1",
        "EXTERNAL_SDVOA",
        "EXTERNAL_SDVOB",
        "TITFP513",
        "INTERNAL_LVTM1",
        "VT1623",
        "HDMI_SI1930",
        "HDMI_INTERNAL",
        "INTERNAL_KLDSCP_TMDS1",
        "INTERNAL_KLDSCP_DVO1",
        "INTERNAL_KLDSCP_DAC1",
        "INTERNAL_KLDSCP_DAC2",
        "SI178",
        "MVPU_FPGA",
        "INTERNAL_DDI",
        "VT1625",
        "HDMI_SI1932",
        "DP_AN9801",
        "DP_DP501",
        "INTERNAL_UNIPHY",
        "INTERNAL_KLDSCP_LVTMA",
        "INTERNAL_UNIPHY1",
        "INTERNAL_UNIPHY2",
        "NUTMEG",
        "TRAVIS",
        "INTERNAL_VCE",
        "INTERNAL_UNIPHY3",
};

static const char *hpd_names[6] = {
        "HPD1",
        "HPD2",
        "HPD3",
        "HPD4",
        "HPD5",
        "HPD6",
};

static void radeon_print_display_setup(struct drm_device *dev)
{
        struct drm_connector *connector;
        struct radeon_connector *radeon_connector;
        struct drm_encoder *encoder;
        struct radeon_encoder *radeon_encoder;
        uint32_t devices;
        int i = 0;

        DRM_INFO("Radeon Display Connectors\n");
        list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
                radeon_connector = to_radeon_connector(connector);
                DRM_INFO("Connector %d:\n", i);
                DRM_INFO("  %s\n", connector->name);
                if (radeon_connector->hpd.hpd != RADEON_HPD_NONE)
                        DRM_INFO("  %s\n", hpd_names[radeon_connector->hpd.hpd]);
                if (radeon_connector->ddc_bus) {
                        DRM_INFO("  DDC: 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
                                 radeon_connector->ddc_bus->rec.mask_clk_reg,
                                 radeon_connector->ddc_bus->rec.mask_data_reg,
                                 radeon_connector->ddc_bus->rec.a_clk_reg,
                                 radeon_connector->ddc_bus->rec.a_data_reg,
                                 radeon_connector->ddc_bus->rec.en_clk_reg,
                                 radeon_connector->ddc_bus->rec.en_data_reg,
                                 radeon_connector->ddc_bus->rec.y_clk_reg,
                                 radeon_connector->ddc_bus->rec.y_data_reg);
                        if (radeon_connector->router.ddc_valid)
                                DRM_INFO("  DDC Router 0x%x/0x%x\n",
                                         radeon_connector->router.ddc_mux_control_pin,
                                         radeon_connector->router.ddc_mux_state);
                        if (radeon_connector->router.cd_valid)
                                DRM_INFO("  Clock/Data Router 0x%x/0x%x\n",
                                         radeon_connector->router.cd_mux_control_pin,
                                         radeon_connector->router.cd_mux_state);
                } else {
                        if (connector->connector_type == DRM_MODE_CONNECTOR_VGA ||
                            connector->connector_type == DRM_MODE_CONNECTOR_DVII ||
                            connector->connector_type == DRM_MODE_CONNECTOR_DVID ||
                            connector->connector_type == DRM_MODE_CONNECTOR_DVIA ||
                            connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
                            connector->connector_type == DRM_MODE_CONNECTOR_HDMIB)
                                DRM_INFO("  DDC: no ddc bus - possible BIOS bug - please report to xorg-driver-ati@lists.x.org\n");
                }
                DRM_INFO("  Encoders:\n");
                list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
                        radeon_encoder = to_radeon_encoder(encoder);
                        devices = radeon_encoder->devices & radeon_connector->devices;
                        if (devices) {
                                if (devices & ATOM_DEVICE_CRT1_SUPPORT)
                                        DRM_INFO("    CRT1: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_CRT2_SUPPORT)
                                        DRM_INFO("    CRT2: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_LCD1_SUPPORT)
                                        DRM_INFO("    LCD1: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP1_SUPPORT)
                                        DRM_INFO("    DFP1: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP2_SUPPORT)
                                        DRM_INFO("    DFP2: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP3_SUPPORT)
                                        DRM_INFO("    DFP3: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP4_SUPPORT)
                                        DRM_INFO("    DFP4: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP5_SUPPORT)
                                        DRM_INFO("    DFP5: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_DFP6_SUPPORT)
                                        DRM_INFO("    DFP6: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_TV1_SUPPORT)
                                        DRM_INFO("    TV1: %s\n", encoder_names[radeon_encoder->encoder_id]);
                                if (devices & ATOM_DEVICE_CV_SUPPORT)
                                        DRM_INFO("    CV: %s\n", encoder_names[radeon_encoder->encoder_id]);
                        }
                }
                i++;
        }
}

static bool radeon_setup_enc_conn(struct drm_device *dev)
{
        struct radeon_device *rdev = dev->dev_private;
        bool ret = false;

        if (rdev->bios) {
                if (rdev->is_atom_bios) {
                        ret = radeon_get_atom_connector_info_from_supported_devices_table(dev);
                        if (ret == false)
                                ret = radeon_get_atom_connector_info_from_object_table(dev);
                } else {
                        ret = radeon_get_legacy_connector_info_from_bios(dev);
                        if (ret == false)
                                ret = radeon_get_legacy_connector_info_from_table(dev);
                }
        } else {
                if (!ASIC_IS_AVIVO(rdev))
                        ret = radeon_get_legacy_connector_info_from_table(dev);
        }
        if (ret) {
                radeon_setup_encoder_clones(dev);
                radeon_print_display_setup(dev);
        }

        return ret;
}

/* avivo */

/**
 * avivo_reduce_ratio - fractional number reduction
 *
 * @nom: nominator
 * @den: denominator
 * @nom_min: minimum value for nominator
 * @den_min: minimum value for denominator
 *
 * Find the greatest common divisor and apply it on both nominator and
 * denominator, but make nominator and denominator are at least as large
 * as their minimum values.
 */
static void avivo_reduce_ratio(unsigned *nom, unsigned *den,
                               unsigned nom_min, unsigned den_min)
{
        unsigned tmp;

        /* reduce the numbers to a simpler ratio */
        tmp = gcd(*nom, *den);
        *nom /= tmp;
        *den /= tmp;

        /* make sure nominator is large enough */
        if (*nom < nom_min) {
                tmp = DIV_ROUND_UP(nom_min, *nom);
                *nom *= tmp;
                *den *= tmp;
        }

        /* make sure the denominator is large enough */
        if (*den < den_min) {
                tmp = DIV_ROUND_UP(den_min, *den);
                *nom *= tmp;
                *den *= tmp;
        }
}

/**
 * avivo_get_fb_ref_div - feedback and ref divider calculation
 *
 * @nom: nominator
 * @den: denominator
 * @post_div: post divider
 * @fb_div_max: feedback divider maximum
 * @ref_div_max: reference divider maximum
 * @fb_div: resulting feedback divider
 * @ref_div: resulting reference divider
 *
 * Calculate feedback and reference divider for a given post divider. Makes
 * sure we stay within the limits.
 */
static void avivo_get_fb_ref_div(unsigned nom, unsigned den, unsigned post_div,
                                 unsigned fb_div_max, unsigned ref_div_max,
                                 unsigned *fb_div, unsigned *ref_div)
{
        /* limit reference * post divider to a maximum */
        ref_div_max = max(min(100 / post_div, ref_div_max), 1u);

        /* get matching reference and feedback divider */
        *ref_div = min(max(den/post_div, 1u), ref_div_max);
        *fb_div = DIV_ROUND_CLOSEST(nom * *ref_div * post_div, den);

        /* limit fb divider to its maximum */
        if (*fb_div > fb_div_max) {
                *ref_div = (*ref_div * fb_div_max)/(*fb_div);
                *fb_div = fb_div_max;
        }
}

/**
 * radeon_compute_pll_avivo - compute PLL paramaters
 *
 * @pll: information about the PLL
 * @dot_clock_p: resulting pixel clock
 * fb_div_p: resulting feedback divider
 * frac_fb_div_p: fractional part of the feedback divider
 * ref_div_p: resulting reference divider
 * post_div_p: resulting reference divider
 *
 * Try to calculate the PLL parameters to generate the given frequency:
 * dot_clock = (ref_freq * feedback_div) / (ref_div * post_div)
 */
void radeon_compute_pll_avivo(struct radeon_pll *pll,
                              u32 freq,
                              u32 *dot_clock_p,
                              u32 *fb_div_p,
                              u32 *frac_fb_div_p,
                              u32 *ref_div_p,
                              u32 *post_div_p)
{
        unsigned target_clock = pll->flags & RADEON_PLL_USE_FRAC_FB_DIV ?
                freq : freq / 10;

        unsigned fb_div_min, fb_div_max, fb_div;
        unsigned post_div_min, post_div_max, post_div;
        unsigned ref_div_min, ref_div_max, ref_div;
        unsigned post_div_best, diff_best;
        unsigned nom, den;

        /* determine allowed feedback divider range */
        fb_div_min = pll->min_feedback_div;
        fb_div_max = pll->max_feedback_div;

        if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV) {
                fb_div_min *= 10;
                fb_div_max *= 10;
        }

        /* determine allowed ref divider range */
        if (pll->flags & RADEON_PLL_USE_REF_DIV)
                ref_div_min = pll->reference_div;
        else
                ref_div_min = pll->min_ref_div;

        if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV &&
            pll->flags & RADEON_PLL_USE_REF_DIV)
                ref_div_max = pll->reference_div;
        else if (pll->flags & RADEON_PLL_PREFER_MINM_OVER_MAXP)
                /* fix for problems on RS880 */
                ref_div_max = min(pll->max_ref_div, 7u);
        else
                ref_div_max = pll->max_ref_div;

        /* determine allowed post divider range */
        if (pll->flags & RADEON_PLL_USE_POST_DIV) {
                post_div_min = pll->post_div;
                post_div_max = pll->post_div;
        } else {
                unsigned vco_min, vco_max;

                if (pll->flags & RADEON_PLL_IS_LCD) {
                        vco_min = pll->lcd_pll_out_min;
                        vco_max = pll->lcd_pll_out_max;
                } else {
                        vco_min = pll->pll_out_min;

                        vco_max = pll->pll_out_max;
                }

                if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV) {
                        vco_min *= 10;
                        vco_max *= 10;
                }

                post_div_min = vco_min / target_clock;
                if ((target_clock * post_div_min) < vco_min)
                        ++post_div_min;
                if (post_div_min < pll->min_post_div)
                        post_div_min = pll->min_post_div;

                post_div_max = vco_max / target_clock;
                if ((target_clock * post_div_max) > vco_max)
                        --post_div_max;
                if (post_div_max > pll->max_post_div)
                        post_div_max = pll->max_post_div;
        }

        /* represent the searched ratio as fractional number */
        nom = target_clock;
        den = pll->reference_freq;

        /* reduce the numbers to a simpler ratio */
        avivo_reduce_ratio(&nom, &den, fb_div_min, post_div_min);

        /* now search for a post divider */
        if (pll->flags & RADEON_PLL_PREFER_MINM_OVER_MAXP)
                post_div_best = post_div_min;
        else
                post_div_best = post_div_max;
        diff_best = ~0;

        for (post_div = post_div_min; post_div <= post_div_max; ++post_div) {
                unsigned diff;
                avivo_get_fb_ref_div(nom, den, post_div, fb_div_max,
                                     ref_div_max, &fb_div, &ref_div);
                diff = abs(target_clock - (pll->reference_freq * fb_div) /
                        (ref_div * post_div));

                if (diff < diff_best || (diff == diff_best &&
                    !(pll->flags & RADEON_PLL_PREFER_MINM_OVER_MAXP))) {

                        post_div_best = post_div;
                        diff_best = diff;
                }
        }
        post_div = post_div_best;

        /* get the feedback and reference divider for the optimal value */
        avivo_get_fb_ref_div(nom, den, post_div, fb_div_max, ref_div_max,
                             &fb_div, &ref_div);

        /* reduce the numbers to a simpler ratio once more */
        /* this also makes sure that the reference divider is large enough */
        avivo_reduce_ratio(&fb_div, &ref_div, fb_div_min, ref_div_min);

        /* avoid high jitter with small fractional dividers */
        if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV && (fb_div % 10)) {
                fb_div_min = max(fb_div_min, (9 - (fb_div % 10)) * 20 + 50);
                if (fb_div < fb_div_min) {
                        unsigned tmp = DIV_ROUND_UP(fb_div_min, fb_div);
                        fb_div *= tmp;
                        ref_div *= tmp;
                }
        }

        /* and finally save the result */
        if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV) {
                *fb_div_p = fb_div / 10;
                *frac_fb_div_p = fb_div % 10;
        } else {
                *fb_div_p = fb_div;
                *frac_fb_div_p = 0;
        }

        *dot_clock_p = ((pll->reference_freq * *fb_div_p * 10) +
                        (pll->reference_freq * *frac_fb_div_p)) /
                       (ref_div * post_div * 10);
        *ref_div_p = ref_div;
        *post_div_p = post_div;

        DRM_DEBUG_KMS("%d - %d, pll dividers - fb: %d.%d ref: %d, post %d\n",
                      freq, *dot_clock_p * 10, *fb_div_p, *frac_fb_div_p,
                      ref_div, post_div);
}

/* pre-avivo */
static inline uint32_t radeon_div(uint64_t n, uint32_t d)
{
        uint64_t mod;

        n += d / 2;

        mod = do_div(n, d);
        return n;
}

void radeon_compute_pll_legacy(struct radeon_pll *pll,
                               uint64_t freq,
                               uint32_t *dot_clock_p,
                               uint32_t *fb_div_p,
                               uint32_t *frac_fb_div_p,
                               uint32_t *ref_div_p,
                               uint32_t *post_div_p)
{
        uint32_t min_ref_div = pll->min_ref_div;
        uint32_t max_ref_div = pll->max_ref_div;
        uint32_t min_post_div = pll->min_post_div;
        uint32_t max_post_div = pll->max_post_div;
        uint32_t min_fractional_feed_div = 0;
        uint32_t max_fractional_feed_div = 0;
        uint32_t best_vco = pll->best_vco;
        uint32_t best_post_div = 1;
        uint32_t best_ref_div = 1;
        uint32_t best_feedback_div = 1;
        uint32_t best_frac_feedback_div = 0;
        uint32_t best_freq = -1;
        uint32_t best_error = 0xffffffff;
        uint32_t best_vco_diff = 1;
        uint32_t post_div;
        u32 pll_out_min, pll_out_max;

        DRM_DEBUG_KMS("PLL freq %llu %u %u\n", freq, pll->min_ref_div, pll->max_ref_div);
        freq = freq * 1000;

        if (pll->flags & RADEON_PLL_IS_LCD) {
                pll_out_min = pll->lcd_pll_out_min;
                pll_out_max = pll->lcd_pll_out_max;
        } else {
                pll_out_min = pll->pll_out_min;
                pll_out_max = pll->pll_out_max;
        }

        if (pll_out_min > 64800)
                pll_out_min = 64800;

        if (pll->flags & RADEON_PLL_USE_REF_DIV)
                min_ref_div = max_ref_div = pll->reference_div;
        else {
                while (min_ref_div < max_ref_div-1) {
                        uint32_t mid = (min_ref_div + max_ref_div) / 2;
                        uint32_t pll_in = pll->reference_freq / mid;
                        if (pll_in < pll->pll_in_min)
                                max_ref_div = mid;
                        else if (pll_in > pll->pll_in_max)
                                min_ref_div = mid;
                        else
                                break;
                }
        }

        if (pll->flags & RADEON_PLL_USE_POST_DIV)
                min_post_div = max_post_div = pll->post_div;

        if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV) {
                min_fractional_feed_div = pll->min_frac_feedback_div;
                max_fractional_feed_div = pll->max_frac_feedback_div;
        }

        for (post_div = max_post_div; post_div >= min_post_div; --post_div) {
                uint32_t ref_div;

                if ((pll->flags & RADEON_PLL_NO_ODD_POST_DIV) && (post_div & 1))
                        continue;

                /* legacy radeons only have a few post_divs */
                if (pll->flags & RADEON_PLL_LEGACY) {
                        if ((post_div == 5) ||
                            (post_div == 7) ||
                            (post_div == 9) ||
                            (post_div == 10) ||
                            (post_div == 11) ||
                            (post_div == 13) ||
                            (post_div == 14) ||
                            (post_div == 15))
                                continue;
                }

                for (ref_div = min_ref_div; ref_div <= max_ref_div; ++ref_div) {
                        uint32_t feedback_div, current_freq = 0, error, vco_diff;
                        uint32_t pll_in = pll->reference_freq / ref_div;
                        uint32_t min_feed_div = pll->min_feedback_div;
                        uint32_t max_feed_div = pll->max_feedback_div + 1;

                        if (pll_in < pll->pll_in_min || pll_in > pll->pll_in_max)
                                continue;

                        while (min_feed_div < max_feed_div) {
                                uint32_t vco;
                                uint32_t min_frac_feed_div = min_fractional_feed_div;
                                uint32_t max_frac_feed_div = max_fractional_feed_div + 1;
                                uint32_t frac_feedback_div;
                                uint64_t tmp;

                                feedback_div = (min_feed_div + max_feed_div) / 2;

                                tmp = (uint64_t)pll->reference_freq * feedback_div;
                                vco = radeon_div(tmp, ref_div);

                                if (vco < pll_out_min) {
                                        min_feed_div = feedback_div + 1;
                                        continue;
                                } else if (vco > pll_out_max) {
                                        max_feed_div = feedback_div;
                                        continue;
                                }

                                while (min_frac_feed_div < max_frac_feed_div) {
                                        frac_feedback_div = (min_frac_feed_div + max_frac_feed_div) / 2;
                                        tmp = (uint64_t)pll->reference_freq * 10000 * feedback_div;
                                        tmp += (uint64_t)pll->reference_freq * 1000 * frac_feedback_div;
                                        current_freq = radeon_div(tmp, ref_div * post_div);

                                        if (pll->flags & RADEON_PLL_PREFER_CLOSEST_LOWER) {
                                                if (freq < current_freq)
                                                        error = 0xffffffff;
                                                else
                                                        error = freq - current_freq;
                                        } else
                                                error = abs(current_freq - freq);
                                        vco_diff = abs(vco - best_vco);

                                        if ((best_vco == 0 && error < best_error) ||
                                            (best_vco != 0 &&
                                             ((best_error > 100 && error < best_error - 100) ||
                                              (abs(error - best_error) < 100 && vco_diff < best_vco_diff)))) {
                                                best_post_div = post_div;
                                                best_ref_div = ref_div;
                                                best_feedback_div = feedback_div;
                                                best_frac_feedback_div = frac_feedback_div;
                                                best_freq = current_freq;
                                                best_error = error;
                                                best_vco_diff = vco_diff;
                                        } else if (current_freq == freq) {
                                                if (best_freq == -1) {
                                                        best_post_div = post_div;
                                                        best_ref_div = ref_div;
                                                        best_feedback_div = feedback_div;
                                                        best_frac_feedback_div = frac_feedback_div;
                                                        best_freq = current_freq;
                                                        best_error = error;
                                                        best_vco_diff = vco_diff;
                                                } else if (((pll->flags & RADEON_PLL_PREFER_LOW_REF_DIV) && (ref_div < best_ref_div)) ||
                                                           ((pll->flags & RADEON_PLL_PREFER_HIGH_REF_DIV) && (ref_div > best_ref_div)) ||
                                                           ((pll->flags & RADEON_PLL_PREFER_LOW_FB_DIV) && (feedback_div < best_feedback_div)) ||
                                                           ((pll->flags & RADEON_PLL_PREFER_HIGH_FB_DIV) && (feedback_div > best_feedback_div)) ||
                                                           ((pll->flags & RADEON_PLL_PREFER_LOW_POST_DIV) && (post_div < best_post_div)) ||
                                                           ((pll->flags & RADEON_PLL_PREFER_HIGH_POST_DIV) && (post_div > best_post_div))) {
                                                        best_post_div = post_div;
                                                        best_ref_div = ref_div;
                                                        best_feedback_div = feedback_div;
                                                        best_frac_feedback_div = frac_feedback_div;
                                                        best_freq = current_freq;
                                                        best_error = error;
                                                        best_vco_diff = vco_diff;
                                                }
                                        }
                                        if (current_freq < freq)
                                                min_frac_feed_div = frac_feedback_div + 1;
                                        else
                                                max_frac_feed_div = frac_feedback_div;
                                }
                                if (current_freq < freq)
                                        min_feed_div = feedback_div + 1;
                                else
                                        max_feed_div = feedback_div;
                        }
                }
        }

        *dot_clock_p = best_freq / 10000;
        *fb_div_p = best_feedback_div;
        *frac_fb_div_p = best_frac_feedback_div;
        *ref_div_p = best_ref_div;
        *post_div_p = best_post_div;
        DRM_DEBUG_KMS("%lld %d, pll dividers - fb: %d.%d ref: %d, post %d\n",
                      (long long)freq,
                      best_freq / 1000, best_feedback_div, best_frac_feedback_div,
                      best_ref_div, best_post_div);

}

static const struct drm_framebuffer_funcs radeon_fb_funcs = {
        .destroy = drm_gem_fb_destroy,
        .create_handle = drm_gem_fb_create_handle,
};

int
radeon_framebuffer_init(struct drm_device *dev,
                        struct drm_framebuffer *fb,
                        const struct drm_mode_fb_cmd2 *mode_cmd,
                        struct drm_gem_object *obj)
{
        int ret;
        fb->obj[0] = obj;
        drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
        ret = drm_framebuffer_init(dev, fb, &radeon_fb_funcs);
        if (ret) {
                fb->obj[0] = NULL;
                return ret;
        }
        return 0;
}

static struct drm_framebuffer *
radeon_user_framebuffer_create(struct drm_device *dev,
                               struct drm_file *file_priv,
                               const struct drm_mode_fb_cmd2 *mode_cmd)
{
        struct drm_gem_object *obj;
        struct drm_framebuffer *fb;
        int ret;

        obj = drm_gem_object_lookup(file_priv, mode_cmd->handles[0]);
        if (obj ==  NULL) {
                dev_err(&dev->pdev->dev, "No GEM object associated to handle 0x%08X, "
                        "can't create framebuffer\n", mode_cmd->handles[0]);
                return ERR_PTR(-ENOENT);
        }

        /* Handle is imported dma-buf, so cannot be migrated to VRAM for scanout */
        if (obj->import_attach) {
                DRM_DEBUG_KMS("Cannot create framebuffer from imported dma_buf\n");
                return ERR_PTR(-EINVAL);
        }

        fb = kzalloc(sizeof(*fb), GFP_KERNEL);
        if (fb == NULL) {
                drm_gem_object_put_unlocked(obj);
                return ERR_PTR(-ENOMEM);
        }

        ret = radeon_framebuffer_init(dev, fb, mode_cmd, obj);
        if (ret) {
                kfree(fb);
                drm_gem_object_put_unlocked(obj);
                return ERR_PTR(ret);
        }

        return fb;
}

static const struct drm_mode_config_funcs radeon_mode_funcs = {
        .fb_create = radeon_user_framebuffer_create,
        .output_poll_changed = drm_fb_helper_output_poll_changed,
};

static const struct drm_prop_enum_list radeon_tmds_pll_enum_list[] =
{       { 0, "driver" },
        { 1, "bios" },
};

static const struct drm_prop_enum_list radeon_tv_std_enum_list[] =
{       { TV_STD_NTSC, "ntsc" },
        { TV_STD_PAL, "pal" },
        { TV_STD_PAL_M, "pal-m" },
        { TV_STD_PAL_60, "pal-60" },
        { TV_STD_NTSC_J, "ntsc-j" },
        { TV_STD_SCART_PAL, "scart-pal" },
        { TV_STD_PAL_CN, "pal-cn" },
        { TV_STD_SECAM, "secam" },
};

static const struct drm_prop_enum_list radeon_underscan_enum_list[] =
{       { UNDERSCAN_OFF, "off" },
        { UNDERSCAN_ON, "on" },
        { UNDERSCAN_AUTO, "auto" },
};

static const struct drm_prop_enum_list radeon_audio_enum_list[] =
{       { RADEON_AUDIO_DISABLE, "off" },
        { RADEON_AUDIO_ENABLE, "on" },
        { RADEON_AUDIO_AUTO, "auto" },
};

/* XXX support different dither options? spatial, temporal, both, etc. */
static const struct drm_prop_enum_list radeon_dither_enum_list[] =
{       { RADEON_FMT_DITHER_DISABLE, "off" },
        { RADEON_FMT_DITHER_ENABLE, "on" },
};

static const struct drm_prop_enum_list radeon_output_csc_enum_list[] =
{       { RADEON_OUTPUT_CSC_BYPASS, "bypass" },
        { RADEON_OUTPUT_CSC_TVRGB, "tvrgb" },
        { RADEON_OUTPUT_CSC_YCBCR601, "ycbcr601" },
        { RADEON_OUTPUT_CSC_YCBCR709, "ycbcr709" },
};

static int radeon_modeset_create_props(struct radeon_device *rdev)
{
        int sz;

        if (rdev->is_atom_bios) {
                rdev->mode_info.coherent_mode_property =
                        drm_property_create_range(rdev->ddev, 0 , "coherent", 0, 1);
                if (!rdev->mode_info.coherent_mode_property)
                        return -ENOMEM;
        }

        if (!ASIC_IS_AVIVO(rdev)) {
                sz = ARRAY_SIZE(radeon_tmds_pll_enum_list);
                rdev->mode_info.tmds_pll_property =
                        drm_property_create_enum(rdev->ddev, 0,
                                            "tmds_pll",
                                            radeon_tmds_pll_enum_list, sz);
        }

        rdev->mode_info.load_detect_property =
                drm_property_create_range(rdev->ddev, 0, "load detection", 0, 1);
        if (!rdev->mode_info.load_detect_property)
                return -ENOMEM;

        drm_mode_create_scaling_mode_property(rdev->ddev);

        sz = ARRAY_SIZE(radeon_tv_std_enum_list);
        rdev->mode_info.tv_std_property =
                drm_property_create_enum(rdev->ddev, 0,
                                    "tv standard",
                                    radeon_tv_std_enum_list, sz);

        sz = ARRAY_SIZE(radeon_underscan_enum_list);
        rdev->mode_info.underscan_property =
                drm_property_create_enum(rdev->ddev, 0,
                                    "underscan",
                                    radeon_underscan_enum_list, sz);

        rdev->mode_info.underscan_hborder_property =
                drm_property_create_range(rdev->ddev, 0,
                                        "underscan hborder", 0, 128);
        if (!rdev->mode_info.underscan_hborder_property)
                return -ENOMEM;

        rdev->mode_info.underscan_vborder_property =
                drm_property_create_range(rdev->ddev, 0,
                                        "underscan vborder", 0, 128);
        if (!rdev->mode_info.underscan_vborder_property)
                return -ENOMEM;

        sz = ARRAY_SIZE(radeon_audio_enum_list);
        rdev->mode_info.audio_property =
                drm_property_create_enum(rdev->ddev, 0,
                                         "audio",
                                         radeon_audio_enum_list, sz);

        sz = ARRAY_SIZE(radeon_dither_enum_list);
        rdev->mode_info.dither_property =
                drm_property_create_enum(rdev->ddev, 0,
                                         "dither",
                                         radeon_dither_enum_list, sz);

        sz = ARRAY_SIZE(radeon_output_csc_enum_list);
        rdev->mode_info.output_csc_property =
                drm_property_create_enum(rdev->ddev, 0,
                                         "output_csc",
                                         radeon_output_csc_enum_list, sz);

        return 0;
}

void radeon_update_display_priority(struct radeon_device *rdev)
{
        /* adjustment options for the display watermarks */
        if ((radeon_disp_priority == 0) || (radeon_disp_priority > 2)) {
                /* set display priority to high for r3xx, rv515 chips
                 * this avoids flickering due to underflow to the
                 * display controllers during heavy acceleration.
                 * Don't force high on rs4xx igp chips as it seems to
                 * affect the sound card.  See kernel bug 15982.
                 */
                if ((ASIC_IS_R300(rdev) || (rdev->family == CHIP_RV515)) &&
                    !(rdev->flags & RADEON_IS_IGP))
                        rdev->disp_priority = 2;
                else
                        rdev->disp_priority = 0;
        } else
                rdev->disp_priority = radeon_disp_priority;

}

/*
 * Allocate hdmi structs and determine register offsets
 */
static void radeon_afmt_init(struct radeon_device *rdev)
{
        int i;

        for (i = 0; i < RADEON_MAX_AFMT_BLOCKS; i++)
                rdev->mode_info.afmt[i] = NULL;

        if (ASIC_IS_NODCE(rdev)) {
                /* nothing to do */
        } else if (ASIC_IS_DCE4(rdev)) {
                static uint32_t eg_offsets[] = {
                        EVERGREEN_CRTC0_REGISTER_OFFSET,
                        EVERGREEN_CRTC1_REGISTER_OFFSET,
                        EVERGREEN_CRTC2_REGISTER_OFFSET,
                        EVERGREEN_CRTC3_REGISTER_OFFSET,
                        EVERGREEN_CRTC4_REGISTER_OFFSET,
                        EVERGREEN_CRTC5_REGISTER_OFFSET,
                        0x13830 - 0x7030,
                };
                int num_afmt;

                /* DCE8 has 7 audio blocks tied to DIG encoders */
                /* DCE6 has 6 audio blocks tied to DIG encoders */
                /* DCE4/5 has 6 audio blocks tied to DIG encoders */
                /* DCE4.1 has 2 audio blocks tied to DIG encoders */
                if (ASIC_IS_DCE8(rdev))
                        num_afmt = 7;
                else if (ASIC_IS_DCE6(rdev))
                        num_afmt = 6;
                else if (ASIC_IS_DCE5(rdev))
                        num_afmt = 6;
                else if (ASIC_IS_DCE41(rdev))
                        num_afmt = 2;
                else /* DCE4 */
                        num_afmt = 6;

                BUG_ON(num_afmt > ARRAY_SIZE(eg_offsets));
                for (i = 0; i < num_afmt; i++) {
                        rdev->mode_info.afmt[i] = kzalloc(sizeof(struct radeon_afmt), GFP_KERNEL);
                        if (rdev->mode_info.afmt[i]) {
                                rdev->mode_info.afmt[i]->offset = eg_offsets[i];
                                rdev->mode_info.afmt[i]->id = i;
                        }
                }
        } else if (ASIC_IS_DCE3(rdev)) {
                /* DCE3.x has 2 audio blocks tied to DIG encoders */
                rdev->mode_info.afmt[0] = kzalloc(sizeof(struct radeon_afmt), GFP_KERNEL);
                if (rdev->mode_info.afmt[0]) {
                        rdev->mode_info.afmt[0]->offset = DCE3_HDMI_OFFSET0;
                        rdev->mode_info.afmt[0]->id = 0;
                }
                rdev->mode_info.afmt[1] = kzalloc(sizeof(struct radeon_afmt), GFP_KERNEL);
                if (rdev->mode_info.afmt[1]) {
                        rdev->mode_info.afmt[1]->offset = DCE3_HDMI_OFFSET1;
                        rdev->mode_info.afmt[1]->id = 1;
                }
        } else if (ASIC_IS_DCE2(rdev)) {
                /* DCE2 has at least 1 routable audio block */
                rdev->mode_info.afmt[0] = kzalloc(sizeof(struct radeon_afmt), GFP_KERNEL);
                if (rdev->mode_info.afmt[0]) {
                        rdev->mode_info.afmt[0]->offset = DCE2_HDMI_OFFSET0;
                        rdev->mode_info.afmt[0]->id = 0;
                }
                /* r6xx has 2 routable audio blocks */
                if (rdev->family >= CHIP_R600) {
                        rdev->mode_info.afmt[1] = kzalloc(sizeof(struct radeon_afmt), GFP_KERNEL);
                        if (rdev->mode_info.afmt[1]) {
                                rdev->mode_info.afmt[1]->offset = DCE2_HDMI_OFFSET1;
                                rdev->mode_info.afmt[1]->id = 1;
                        }
                }
        }
}

static void radeon_afmt_fini(struct radeon_device *rdev)
{
        int i;

        for (i = 0; i < RADEON_MAX_AFMT_BLOCKS; i++) {
                kfree(rdev->mode_info.afmt[i]);
                rdev->mode_info.afmt[i] = NULL;
        }
}

int radeon_modeset_init(struct radeon_device *rdev)
{
        int i;
        int ret;

        drm_mode_config_init(rdev->ddev);
        rdev->mode_info.mode_config_initialized = true;

        rdev->ddev->mode_config.funcs = &radeon_mode_funcs;

        if (radeon_use_pflipirq == 2 && rdev->family >= CHIP_R600)
                rdev->ddev->mode_config.async_page_flip = true;

        if (ASIC_IS_DCE5(rdev)) {
                rdev->ddev->mode_config.max_width = 16384;
                rdev->ddev->mode_config.max_height = 16384;
        } else if (ASIC_IS_AVIVO(rdev)) {
                rdev->ddev->mode_config.max_width = 8192;
                rdev->ddev->mode_config.max_height = 8192;
        } else {
                rdev->ddev->mode_config.max_width = 4096;
                rdev->ddev->mode_config.max_height = 4096;
        }

        rdev->ddev->mode_config.preferred_depth = 24;
        rdev->ddev->mode_config.prefer_shadow = 1;

        rdev->ddev->mode_config.fb_base = rdev->mc.aper_base;

        ret = radeon_modeset_create_props(rdev);
        if (ret) {
                return ret;
        }

        /* init i2c buses */
        radeon_i2c_init(rdev);

        /* check combios for a valid hardcoded EDID - Sun servers */
        if (!rdev->is_atom_bios) {
                /* check for hardcoded EDID in BIOS */
                radeon_combios_check_hardcoded_edid(rdev);
        }

        /* allocate crtcs */
        for (i = 0; i < rdev->num_crtc; i++) {
                radeon_crtc_init(rdev->ddev, i);
        }

        /* okay we should have all the bios connectors */
        ret = radeon_setup_enc_conn(rdev->ddev);
        if (!ret) {
                return ret;
        }

        /* init dig PHYs, disp eng pll */
        if (rdev->is_atom_bios) {
                radeon_atom_encoder_init(rdev);
                radeon_atom_disp_eng_pll_init(rdev);
        }

        /* initialize hpd */
        radeon_hpd_init(rdev);

        /* setup afmt */
        radeon_afmt_init(rdev);

        radeon_fbdev_init(rdev);
        drm_kms_helper_poll_init(rdev->ddev);

        /* do pm late init */
        ret = radeon_pm_late_init(rdev);

        return 0;
}

void radeon_modeset_fini(struct radeon_device *rdev)
{
        if (rdev->mode_info.mode_config_initialized) {
                drm_kms_helper_poll_fini(rdev->ddev);
                radeon_hpd_fini(rdev);
                drm_helper_force_disable_all(rdev->ddev);
                radeon_fbdev_fini(rdev);
                radeon_afmt_fini(rdev);
                drm_mode_config_cleanup(rdev->ddev);
                rdev->mode_info.mode_config_initialized = false;
        }

        kfree(rdev->mode_info.bios_hardcoded_edid);

        /* free i2c buses */
        radeon_i2c_fini(rdev);
}

static bool is_hdtv_mode(const struct drm_display_mode *mode)
{
        /* try and guess if this is a tv or a monitor */
        if ((mode->vdisplay == 480 && mode->hdisplay == 720) || /* 480p */
            (mode->vdisplay == 576) || /* 576p */
            (mode->vdisplay == 720) || /* 720p */
            (mode->vdisplay == 1080)) /* 1080p */
                return true;
        else
                return false;
}

bool radeon_crtc_scaling_mode_fixup(struct drm_crtc *crtc,
                                const struct drm_display_mode *mode,
                                struct drm_display_mode *adjusted_mode)
{
        struct drm_device *dev = crtc->dev;
        struct radeon_device *rdev = dev->dev_private;
        struct drm_encoder *encoder;
        struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
        struct radeon_encoder *radeon_encoder;
        struct drm_connector *connector;
        struct radeon_connector *radeon_connector;
        bool first = true;
        u32 src_v = 1, dst_v = 1;
        u32 src_h = 1, dst_h = 1;

        radeon_crtc->h_border = 0;
        radeon_crtc->v_border = 0;

        list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
                if (encoder->crtc != crtc)
                        continue;
                radeon_encoder = to_radeon_encoder(encoder);
                connector = radeon_get_connector_for_encoder(encoder);
                radeon_connector = to_radeon_connector(connector);

                if (first) {
                        /* set scaling */
                        if (radeon_encoder->rmx_type == RMX_OFF)
                                radeon_crtc->rmx_type = RMX_OFF;
                        else if (mode->hdisplay < radeon_encoder->native_mode.hdisplay ||
                                 mode->vdisplay < radeon_encoder->native_mode.vdisplay)
                                radeon_crtc->rmx_type = radeon_encoder->rmx_type;
                        else
                                radeon_crtc->rmx_type = RMX_OFF;
                        /* copy native mode */
                        memcpy(&radeon_crtc->native_mode,
                               &radeon_encoder->native_mode,
                                sizeof(struct drm_display_mode));
                        src_v = crtc->mode.vdisplay;
                        dst_v = radeon_crtc->native_mode.vdisplay;
                        src_h = crtc->mode.hdisplay;
                        dst_h = radeon_crtc->native_mode.hdisplay;

                        /* fix up for overscan on hdmi */
                        if (ASIC_IS_AVIVO(rdev) &&
                            (!(mode->flags & DRM_MODE_FLAG_INTERLACE)) &&
                            ((radeon_encoder->underscan_type == UNDERSCAN_ON) ||
                             ((radeon_encoder->underscan_type == UNDERSCAN_AUTO) &&
                              drm_detect_hdmi_monitor(radeon_connector_edid(connector)) &&
                              is_hdtv_mode(mode)))) {
                                if (radeon_encoder->underscan_hborder != 0)
                                        radeon_crtc->h_border = radeon_encoder->underscan_hborder;
                                else
                                        radeon_crtc->h_border = (mode->hdisplay >> 5) + 16;
                                if (radeon_encoder->underscan_vborder != 0)
                                        radeon_crtc->v_border = radeon_encoder->underscan_vborder;
                                else
                                        radeon_crtc->v_border = (mode->vdisplay >> 5) + 16;
                                radeon_crtc->rmx_type = RMX_FULL;
                                src_v = crtc->mode.vdisplay;
                                dst_v = crtc->mode.vdisplay - (radeon_crtc->v_border * 2);
                                src_h = crtc->mode.hdisplay;
                                dst_h = crtc->mode.hdisplay - (radeon_crtc->h_border * 2);
                        }
                        first = false;
                } else {
                        if (radeon_crtc->rmx_type != radeon_encoder->rmx_type) {
                                /* WARNING: Right now this can't happen but
                                 * in the future we need to check that scaling
                                 * are consistent across different encoder
                                 * (ie all encoder can work with the same
                                 *  scaling).
                                 */
                                DRM_ERROR("Scaling not consistent across encoder.\n");
                                return false;
                        }
                }
        }
        if (radeon_crtc->rmx_type != RMX_OFF) {
                fixed20_12 a, b;
                a.full = dfixed_const(src_v);
                b.full = dfixed_const(dst_v);
                radeon_crtc->vsc.full = dfixed_div(a, b);
                a.full = dfixed_const(src_h);
                b.full = dfixed_const(dst_h);
                radeon_crtc->hsc.full = dfixed_div(a, b);
        } else {
                radeon_crtc->vsc.full = dfixed_const(1);
                radeon_crtc->hsc.full = dfixed_const(1);
        }
        return true;
}

/*
 * Retrieve current video scanout position of crtc on a given gpu, and
 * an optional accurate timestamp of when query happened.
 *
 * \param dev Device to query.
 * \param crtc Crtc to query.
 * \param flags Flags from caller (DRM_CALLED_FROM_VBLIRQ or 0).
 *              For driver internal use only also supports these flags:
 *
 *              USE_REAL_VBLANKSTART to use the real start of vblank instead
 *              of a fudged earlier start of vblank.
 *
 *              GET_DISTANCE_TO_VBLANKSTART to return distance to the
 *              fudged earlier start of vblank in *vpos and the distance
 *              to true start of vblank in *hpos.
 *
 * \param *vpos Location where vertical scanout position should be stored.
 * \param *hpos Location where horizontal scanout position should go.
 * \param *stime Target location for timestamp taken immediately before
 *               scanout position query. Can be NULL to skip timestamp.
 * \param *etime Target location for timestamp taken immediately after
 *               scanout position query. Can be NULL to skip timestamp.
 *
 * Returns vpos as a positive number while in active scanout area.
 * Returns vpos as a negative number inside vblank, counting the number
 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
 * until start of active scanout / end of vblank."
 *
 * \return Flags, or'ed together as follows:
 *
 * DRM_SCANOUTPOS_VALID = Query successful.
 * DRM_SCANOUTPOS_INVBL = Inside vblank.
 * DRM_SCANOUTPOS_ACCURATE = Returned position is accurate. A lack of
 * this flag means that returned position may be offset by a constant but
 * unknown small number of scanlines wrt. real scanout position.
 *
 */
int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
                               unsigned int flags, int *vpos, int *hpos,
                               ktime_t *stime, ktime_t *etime,
                               const struct drm_display_mode *mode)
{
        u32 stat_crtc = 0, vbl = 0, position = 0;
        int vbl_start, vbl_end, vtotal, ret = 0;
        bool in_vbl = true;

        struct radeon_device *rdev = dev->dev_private;

        /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */

        /* Get optional system timestamp before query. */
        if (stime)
                *stime = ktime_get();

        if (ASIC_IS_DCE4(rdev)) {
                if (pipe == 0) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC0_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC0_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 1) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC1_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC1_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 2) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC2_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC2_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 3) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC3_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC3_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 4) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC4_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC4_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 5) {
                        vbl = RREG32(EVERGREEN_CRTC_V_BLANK_START_END +
                                     EVERGREEN_CRTC5_REGISTER_OFFSET);
                        position = RREG32(EVERGREEN_CRTC_STATUS_POSITION +
                                          EVERGREEN_CRTC5_REGISTER_OFFSET);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
        } else if (ASIC_IS_AVIVO(rdev)) {
                if (pipe == 0) {
                        vbl = RREG32(AVIVO_D1CRTC_V_BLANK_START_END);
                        position = RREG32(AVIVO_D1CRTC_STATUS_POSITION);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 1) {
                        vbl = RREG32(AVIVO_D2CRTC_V_BLANK_START_END);
                        position = RREG32(AVIVO_D2CRTC_STATUS_POSITION);
                        ret |= DRM_SCANOUTPOS_VALID;
                }
        } else {
                /* Pre-AVIVO: Different encoding of scanout pos and vblank interval. */
                if (pipe == 0) {
                        /* Assume vbl_end == 0, get vbl_start from
                         * upper 16 bits.
                         */
                        vbl = (RREG32(RADEON_CRTC_V_TOTAL_DISP) &
                                RADEON_CRTC_V_DISP) >> RADEON_CRTC_V_DISP_SHIFT;
                        /* Only retrieve vpos from upper 16 bits, set hpos == 0. */
                        position = (RREG32(RADEON_CRTC_VLINE_CRNT_VLINE) >> 16) & RADEON_CRTC_V_TOTAL;
                        stat_crtc = RREG32(RADEON_CRTC_STATUS);
                        if (!(stat_crtc & 1))
                                in_vbl = false;

                        ret |= DRM_SCANOUTPOS_VALID;
                }
                if (pipe == 1) {
                        vbl = (RREG32(RADEON_CRTC2_V_TOTAL_DISP) &
                                RADEON_CRTC_V_DISP) >> RADEON_CRTC_V_DISP_SHIFT;
                        position = (RREG32(RADEON_CRTC2_VLINE_CRNT_VLINE) >> 16) & RADEON_CRTC_V_TOTAL;
                        stat_crtc = RREG32(RADEON_CRTC2_STATUS);
                        if (!(stat_crtc & 1))
                                in_vbl = false;

                        ret |= DRM_SCANOUTPOS_VALID;
                }
        }

        /* Get optional system timestamp after query. */
        if (etime)
                *etime = ktime_get();

        /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */

        /* Decode into vertical and horizontal scanout position. */
        *vpos = position & 0x1fff;
        *hpos = (position >> 16) & 0x1fff;

        /* Valid vblank area boundaries from gpu retrieved? */
        if (vbl > 0) {
                /* Yes: Decode. */
                ret |= DRM_SCANOUTPOS_ACCURATE;
                vbl_start = vbl & 0x1fff;
                vbl_end = (vbl >> 16) & 0x1fff;
        }
        else {
                /* No: Fake something reasonable which gives at least ok results. */
                vbl_start = mode->crtc_vdisplay;
                vbl_end = 0;
        }

        /* Called from driver internal vblank counter query code? */
        if (flags & GET_DISTANCE_TO_VBLANKSTART) {
            /* Caller wants distance from real vbl_start in *hpos */
            *hpos = *vpos - vbl_start;
        }

        /* Fudge vblank to start a few scanlines earlier to handle the
         * problem that vblank irqs fire a few scanlines before start
         * of vblank. Some driver internal callers need the true vblank
         * start to be used and signal this via the USE_REAL_VBLANKSTART flag.
         *
         * The cause of the "early" vblank irq is that the irq is triggered
         * by the line buffer logic when the line buffer read position enters
         * the vblank, whereas our crtc scanout position naturally lags the
         * line buffer read position.
         */
        if (!(flags & USE_REAL_VBLANKSTART))
                vbl_start -= rdev->mode_info.crtcs[pipe]->lb_vblank_lead_lines;

        /* Test scanout position against vblank region. */
        if ((*vpos < vbl_start) && (*vpos >= vbl_end))
                in_vbl = false;

        /* In vblank? */
        if (in_vbl)
            ret |= DRM_SCANOUTPOS_IN_VBLANK;

        /* Called from driver internal vblank counter query code? */
        if (flags & GET_DISTANCE_TO_VBLANKSTART) {
                /* Caller wants distance from fudged earlier vbl_start */
                *vpos -= vbl_start;
                return ret;
        }

        /* Check if inside vblank area and apply corrective offsets:
         * vpos will then be >=0 in video scanout area, but negative
         * within vblank area, counting down the number of lines until
         * start of scanout.
         */

        /* Inside "upper part" of vblank area? Apply corrective offset if so: */
        if (in_vbl && (*vpos >= vbl_start)) {
                vtotal = mode->crtc_vtotal;
                *vpos = *vpos - vtotal;
        }

        /* Correct for shifted end of vbl at vbl_end. */
        *vpos = *vpos - vbl_end;

        return ret;
}