treewide: remove redundant IS_ERR() before error code check

[linux/fpc-iii.git] / drivers / gpu / drm / msm / disp / dpu1 / dpu_crtc.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014-2018 The Linux Foundation. All rights reserved.
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */

#define pr_fmt(fmt)     "[drm:%s:%d] " fmt, __func__, __LINE__
#include <linux/sort.h>
#include <linux/debugfs.h>
#include <linux/ktime.h>

#include <drm/drm_crtc.h>
#include <drm/drm_flip_work.h>
#include <drm/drm_mode.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_rect.h>
#include <drm/drm_vblank.h>

#include "dpu_kms.h"
#include "dpu_hw_lm.h"
#include "dpu_hw_ctl.h"
#include "dpu_crtc.h"
#include "dpu_plane.h"
#include "dpu_encoder.h"
#include "dpu_vbif.h"
#include "dpu_core_perf.h"
#include "dpu_trace.h"

#define DPU_DRM_BLEND_OP_NOT_DEFINED    0
#define DPU_DRM_BLEND_OP_OPAQUE         1
#define DPU_DRM_BLEND_OP_PREMULTIPLIED  2
#define DPU_DRM_BLEND_OP_COVERAGE       3
#define DPU_DRM_BLEND_OP_MAX            4

/* layer mixer index on dpu_crtc */
#define LEFT_MIXER 0
#define RIGHT_MIXER 1

/* timeout in ms waiting for frame done */
#define DPU_CRTC_FRAME_DONE_TIMEOUT_MS  60

static struct dpu_kms *_dpu_crtc_get_kms(struct drm_crtc *crtc)
{
        struct msm_drm_private *priv = crtc->dev->dev_private;

        return to_dpu_kms(priv->kms);
}

static void dpu_crtc_destroy(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);

        DPU_DEBUG("\n");

        if (!crtc)
                return;

        drm_crtc_cleanup(crtc);
        kfree(dpu_crtc);
}

static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,
                struct dpu_plane_state *pstate, struct dpu_format *format)
{
        struct dpu_hw_mixer *lm = mixer->hw_lm;
        uint32_t blend_op;
        struct drm_format_name_buf format_name;

        /* default to opaque blending */
        blend_op = DPU_BLEND_FG_ALPHA_FG_CONST |
                DPU_BLEND_BG_ALPHA_BG_CONST;

        if (format->alpha_enable) {
                /* coverage blending */
                blend_op = DPU_BLEND_FG_ALPHA_FG_PIXEL |
                        DPU_BLEND_BG_ALPHA_FG_PIXEL |
                        DPU_BLEND_BG_INV_ALPHA;
        }

        lm->ops.setup_blend_config(lm, pstate->stage,
                                0xFF, 0, blend_op);

        DPU_DEBUG("format:%s, alpha_en:%u blend_op:0x%x\n",
                drm_get_format_name(format->base.pixel_format, &format_name),
                format->alpha_enable, blend_op);
}

static void _dpu_crtc_program_lm_output_roi(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_crtc_state *crtc_state;
        int lm_idx, lm_horiz_position;

        dpu_crtc = to_dpu_crtc(crtc);
        crtc_state = to_dpu_crtc_state(crtc->state);

        lm_horiz_position = 0;
        for (lm_idx = 0; lm_idx < crtc_state->num_mixers; lm_idx++) {
                const struct drm_rect *lm_roi = &crtc_state->lm_bounds[lm_idx];
                struct dpu_hw_mixer *hw_lm = crtc_state->mixers[lm_idx].hw_lm;
                struct dpu_hw_mixer_cfg cfg;

                if (!lm_roi || !drm_rect_visible(lm_roi))
                        continue;

                cfg.out_width = drm_rect_width(lm_roi);
                cfg.out_height = drm_rect_height(lm_roi);
                cfg.right_mixer = lm_horiz_position++;
                cfg.flags = 0;
                hw_lm->ops.setup_mixer_out(hw_lm, &cfg);
        }
}

static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
        struct dpu_crtc *dpu_crtc, struct dpu_crtc_mixer *mixer)
{
        struct drm_plane *plane;
        struct drm_framebuffer *fb;
        struct drm_plane_state *state;
        struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc->state);
        struct dpu_plane_state *pstate = NULL;
        struct dpu_format *format;
        struct dpu_hw_ctl *ctl = mixer->lm_ctl;
        struct dpu_hw_stage_cfg *stage_cfg = &dpu_crtc->stage_cfg;

        u32 flush_mask;
        uint32_t stage_idx, lm_idx;
        int zpos_cnt[DPU_STAGE_MAX + 1] = { 0 };
        bool bg_alpha_enable = false;

        drm_atomic_crtc_for_each_plane(plane, crtc) {
                state = plane->state;
                if (!state)
                        continue;

                pstate = to_dpu_plane_state(state);
                fb = state->fb;

                dpu_plane_get_ctl_flush(plane, ctl, &flush_mask);

                DPU_DEBUG("crtc %d stage:%d - plane %d sspp %d fb %d\n",
                                crtc->base.id,
                                pstate->stage,
                                plane->base.id,
                                dpu_plane_pipe(plane) - SSPP_VIG0,
                                state->fb ? state->fb->base.id : -1);

                format = to_dpu_format(msm_framebuffer_format(pstate->base.fb));

                if (pstate->stage == DPU_STAGE_BASE && format->alpha_enable)
                        bg_alpha_enable = true;

                stage_idx = zpos_cnt[pstate->stage]++;
                stage_cfg->stage[pstate->stage][stage_idx] =
                                        dpu_plane_pipe(plane);
                stage_cfg->multirect_index[pstate->stage][stage_idx] =
                                        pstate->multirect_index;

                trace_dpu_crtc_setup_mixer(DRMID(crtc), DRMID(plane),
                                           state, pstate, stage_idx,
                                           dpu_plane_pipe(plane) - SSPP_VIG0,
                                           format->base.pixel_format,
                                           fb ? fb->modifier : 0);

                /* blend config update */
                for (lm_idx = 0; lm_idx < cstate->num_mixers; lm_idx++) {
                        _dpu_crtc_setup_blend_cfg(mixer + lm_idx,
                                                pstate, format);

                        mixer[lm_idx].flush_mask |= flush_mask;

                        if (bg_alpha_enable && !format->alpha_enable)
                                mixer[lm_idx].mixer_op_mode = 0;
                        else
                                mixer[lm_idx].mixer_op_mode |=
                                                1 << pstate->stage;
                }
        }

         _dpu_crtc_program_lm_output_roi(crtc);
}

/**
 * _dpu_crtc_blend_setup - configure crtc mixers
 * @crtc: Pointer to drm crtc structure
 */
static void _dpu_crtc_blend_setup(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc->state);
        struct dpu_crtc_mixer *mixer = cstate->mixers;
        struct dpu_hw_ctl *ctl;
        struct dpu_hw_mixer *lm;
        int i;

        DPU_DEBUG("%s\n", dpu_crtc->name);

        for (i = 0; i < cstate->num_mixers; i++) {
                mixer[i].mixer_op_mode = 0;
                mixer[i].flush_mask = 0;
                if (mixer[i].lm_ctl->ops.clear_all_blendstages)
                        mixer[i].lm_ctl->ops.clear_all_blendstages(
                                        mixer[i].lm_ctl);
        }

        /* initialize stage cfg */
        memset(&dpu_crtc->stage_cfg, 0, sizeof(struct dpu_hw_stage_cfg));

        _dpu_crtc_blend_setup_mixer(crtc, dpu_crtc, mixer);

        for (i = 0; i < cstate->num_mixers; i++) {
                ctl = mixer[i].lm_ctl;
                lm = mixer[i].hw_lm;

                lm->ops.setup_alpha_out(lm, mixer[i].mixer_op_mode);

                mixer[i].flush_mask |= ctl->ops.get_bitmask_mixer(ctl,
                        mixer[i].hw_lm->idx);

                /* stage config flush mask */
                ctl->ops.update_pending_flush(ctl, mixer[i].flush_mask);

                DPU_DEBUG("lm %d, op_mode 0x%X, ctl %d, flush mask 0x%x\n",
                        mixer[i].hw_lm->idx - LM_0,
                        mixer[i].mixer_op_mode,
                        ctl->idx - CTL_0,
                        mixer[i].flush_mask);

                ctl->ops.setup_blendstage(ctl, mixer[i].hw_lm->idx,
                        &dpu_crtc->stage_cfg);
        }
}

/**
 *  _dpu_crtc_complete_flip - signal pending page_flip events
 * Any pending vblank events are added to the vblank_event_list
 * so that the next vblank interrupt shall signal them.
 * However PAGE_FLIP events are not handled through the vblank_event_list.
 * This API signals any pending PAGE_FLIP events requested through
 * DRM_IOCTL_MODE_PAGE_FLIP and are cached in the dpu_crtc->event.
 * @crtc: Pointer to drm crtc structure
 */
static void _dpu_crtc_complete_flip(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        struct drm_device *dev = crtc->dev;
        unsigned long flags;

        spin_lock_irqsave(&dev->event_lock, flags);
        if (dpu_crtc->event) {
                DRM_DEBUG_VBL("%s: send event: %pK\n", dpu_crtc->name,
                              dpu_crtc->event);
                trace_dpu_crtc_complete_flip(DRMID(crtc));
                drm_crtc_send_vblank_event(crtc, dpu_crtc->event);
                dpu_crtc->event = NULL;
        }
        spin_unlock_irqrestore(&dev->event_lock, flags);
}

enum dpu_intf_mode dpu_crtc_get_intf_mode(struct drm_crtc *crtc)
{
        struct drm_encoder *encoder;

        if (!crtc) {
                DPU_ERROR("invalid crtc\n");
                return INTF_MODE_NONE;
        }

        /*
         * TODO: This function is called from dpu debugfs and as part of atomic
         * check. When called from debugfs, the crtc->mutex must be held to
         * read crtc->state. However reading crtc->state from atomic check isn't
         * allowed (unless you have a good reason, a big comment, and a deep
         * understanding of how the atomic/modeset locks work (<- and this is
         * probably not possible)). So we'll keep the WARN_ON here for now, but
         * really we need to figure out a better way to track our operating mode
         */
        WARN_ON(!drm_modeset_is_locked(&crtc->mutex));

        /* TODO: Returns the first INTF_MODE, could there be multiple values? */
        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
                return dpu_encoder_get_intf_mode(encoder);

        return INTF_MODE_NONE;
}

void dpu_crtc_vblank_callback(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);

        /* keep statistics on vblank callback - with auto reset via debugfs */
        if (ktime_compare(dpu_crtc->vblank_cb_time, ktime_set(0, 0)) == 0)
                dpu_crtc->vblank_cb_time = ktime_get();
        else
                dpu_crtc->vblank_cb_count++;
        _dpu_crtc_complete_flip(crtc);
        drm_crtc_handle_vblank(crtc);
        trace_dpu_crtc_vblank_cb(DRMID(crtc));
}

static void dpu_crtc_frame_event_work(struct kthread_work *work)
{
        struct dpu_crtc_frame_event *fevent = container_of(work,
                        struct dpu_crtc_frame_event, work);
        struct drm_crtc *crtc = fevent->crtc;
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        unsigned long flags;
        bool frame_done = false;

        DPU_ATRACE_BEGIN("crtc_frame_event");

        DRM_DEBUG_KMS("crtc%d event:%u ts:%lld\n", crtc->base.id, fevent->event,
                        ktime_to_ns(fevent->ts));

        if (fevent->event & (DPU_ENCODER_FRAME_EVENT_DONE
                                | DPU_ENCODER_FRAME_EVENT_ERROR
                                | DPU_ENCODER_FRAME_EVENT_PANEL_DEAD)) {

                if (atomic_read(&dpu_crtc->frame_pending) < 1) {
                        /* ignore vblank when not pending */
                } else if (atomic_dec_return(&dpu_crtc->frame_pending) == 0) {
                        /* release bandwidth and other resources */
                        trace_dpu_crtc_frame_event_done(DRMID(crtc),
                                                        fevent->event);
                        dpu_core_perf_crtc_release_bw(crtc);
                } else {
                        trace_dpu_crtc_frame_event_more_pending(DRMID(crtc),
                                                                fevent->event);
                }

                if (fevent->event & DPU_ENCODER_FRAME_EVENT_DONE)
                        dpu_core_perf_crtc_update(crtc, 0, false);

                if (fevent->event & (DPU_ENCODER_FRAME_EVENT_DONE
                                        | DPU_ENCODER_FRAME_EVENT_ERROR))
                        frame_done = true;
        }

        if (fevent->event & DPU_ENCODER_FRAME_EVENT_PANEL_DEAD)
                DPU_ERROR("crtc%d ts:%lld received panel dead event\n",
                                crtc->base.id, ktime_to_ns(fevent->ts));

        if (frame_done)
                complete_all(&dpu_crtc->frame_done_comp);

        spin_lock_irqsave(&dpu_crtc->spin_lock, flags);
        list_add_tail(&fevent->list, &dpu_crtc->frame_event_list);
        spin_unlock_irqrestore(&dpu_crtc->spin_lock, flags);
        DPU_ATRACE_END("crtc_frame_event");
}

/*
 * dpu_crtc_frame_event_cb - crtc frame event callback API. CRTC module
 * registers this API to encoder for all frame event callbacks like
 * frame_error, frame_done, idle_timeout, etc. Encoder may call different events
 * from different context - IRQ, user thread, commit_thread, etc. Each event
 * should be carefully reviewed and should be processed in proper task context
 * to avoid schedulin delay or properly manage the irq context's bottom half
 * processing.
 */
static void dpu_crtc_frame_event_cb(void *data, u32 event)
{
        struct drm_crtc *crtc = (struct drm_crtc *)data;
        struct dpu_crtc *dpu_crtc;
        struct msm_drm_private *priv;
        struct dpu_crtc_frame_event *fevent;
        unsigned long flags;
        u32 crtc_id;

        /* Nothing to do on idle event */
        if (event & DPU_ENCODER_FRAME_EVENT_IDLE)
                return;

        dpu_crtc = to_dpu_crtc(crtc);
        priv = crtc->dev->dev_private;
        crtc_id = drm_crtc_index(crtc);

        trace_dpu_crtc_frame_event_cb(DRMID(crtc), event);

        spin_lock_irqsave(&dpu_crtc->spin_lock, flags);
        fevent = list_first_entry_or_null(&dpu_crtc->frame_event_list,
                        struct dpu_crtc_frame_event, list);
        if (fevent)
                list_del_init(&fevent->list);
        spin_unlock_irqrestore(&dpu_crtc->spin_lock, flags);

        if (!fevent) {
                DRM_ERROR("crtc%d event %d overflow\n", crtc->base.id, event);
                return;
        }

        fevent->event = event;
        fevent->crtc = crtc;
        fevent->ts = ktime_get();
        kthread_queue_work(&priv->event_thread[crtc_id].worker, &fevent->work);
}

void dpu_crtc_complete_commit(struct drm_crtc *crtc)
{
        trace_dpu_crtc_complete_commit(DRMID(crtc));
}

static void _dpu_crtc_setup_lm_bounds(struct drm_crtc *crtc,
                struct drm_crtc_state *state)
{
        struct dpu_crtc_state *cstate = to_dpu_crtc_state(state);
        struct drm_display_mode *adj_mode = &state->adjusted_mode;
        u32 crtc_split_width = adj_mode->hdisplay / cstate->num_mixers;
        int i;

        for (i = 0; i < cstate->num_mixers; i++) {
                struct drm_rect *r = &cstate->lm_bounds[i];
                r->x1 = crtc_split_width * i;
                r->y1 = 0;
                r->x2 = r->x1 + crtc_split_width;
                r->y2 = adj_mode->vdisplay;

                trace_dpu_crtc_setup_lm_bounds(DRMID(crtc), i, r);
        }

        drm_mode_debug_printmodeline(adj_mode);
}

static void dpu_crtc_atomic_begin(struct drm_crtc *crtc,
                struct drm_crtc_state *old_state)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_crtc_state *cstate;
        struct drm_encoder *encoder;
        struct drm_device *dev;
        unsigned long flags;
        struct dpu_crtc_smmu_state_data *smmu_state;

        if (!crtc) {
                DPU_ERROR("invalid crtc\n");
                return;
        }

        if (!crtc->state->enable) {
                DPU_DEBUG("crtc%d -> enable %d, skip atomic_begin\n",
                                crtc->base.id, crtc->state->enable);
                return;
        }

        DPU_DEBUG("crtc%d\n", crtc->base.id);

        dpu_crtc = to_dpu_crtc(crtc);
        cstate = to_dpu_crtc_state(crtc->state);
        dev = crtc->dev;
        smmu_state = &dpu_crtc->smmu_state;

        _dpu_crtc_setup_lm_bounds(crtc, crtc->state);

        if (dpu_crtc->event) {
                WARN_ON(dpu_crtc->event);
        } else {
                spin_lock_irqsave(&dev->event_lock, flags);
                dpu_crtc->event = crtc->state->event;
                crtc->state->event = NULL;
                spin_unlock_irqrestore(&dev->event_lock, flags);
        }

        /* encoder will trigger pending mask now */
        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
                dpu_encoder_trigger_kickoff_pending(encoder);

        /*
         * If no mixers have been allocated in dpu_crtc_atomic_check(),
         * it means we are trying to flush a CRTC whose state is disabled:
         * nothing else needs to be done.
         */
        if (unlikely(!cstate->num_mixers))
                return;

        _dpu_crtc_blend_setup(crtc);

        /*
         * PP_DONE irq is only used by command mode for now.
         * It is better to request pending before FLUSH and START trigger
         * to make sure no pp_done irq missed.
         * This is safe because no pp_done will happen before SW trigger
         * in command mode.
         */
}

static void dpu_crtc_atomic_flush(struct drm_crtc *crtc,
                struct drm_crtc_state *old_crtc_state)
{
        struct dpu_crtc *dpu_crtc;
        struct drm_device *dev;
        struct drm_plane *plane;
        struct msm_drm_private *priv;
        struct msm_drm_thread *event_thread;
        unsigned long flags;
        struct dpu_crtc_state *cstate;

        if (!crtc->state->enable) {
                DPU_DEBUG("crtc%d -> enable %d, skip atomic_flush\n",
                                crtc->base.id, crtc->state->enable);
                return;
        }

        DPU_DEBUG("crtc%d\n", crtc->base.id);

        dpu_crtc = to_dpu_crtc(crtc);
        cstate = to_dpu_crtc_state(crtc->state);
        dev = crtc->dev;
        priv = dev->dev_private;

        if (crtc->index >= ARRAY_SIZE(priv->event_thread)) {
                DPU_ERROR("invalid crtc index[%d]\n", crtc->index);
                return;
        }

        event_thread = &priv->event_thread[crtc->index];

        if (dpu_crtc->event) {
                DPU_DEBUG("already received dpu_crtc->event\n");
        } else {
                spin_lock_irqsave(&dev->event_lock, flags);
                dpu_crtc->event = crtc->state->event;
                crtc->state->event = NULL;
                spin_unlock_irqrestore(&dev->event_lock, flags);
        }

        /*
         * If no mixers has been allocated in dpu_crtc_atomic_check(),
         * it means we are trying to flush a CRTC whose state is disabled:
         * nothing else needs to be done.
         */
        if (unlikely(!cstate->num_mixers))
                return;

        /*
         * For planes without commit update, drm framework will not add
         * those planes to current state since hardware update is not
         * required. However, if those planes were power collapsed since
         * last commit cycle, driver has to restore the hardware state
         * of those planes explicitly here prior to plane flush.
         */
        drm_atomic_crtc_for_each_plane(plane, crtc)
                dpu_plane_restore(plane);

        /* update performance setting before crtc kickoff */
        dpu_core_perf_crtc_update(crtc, 1, false);

        /*
         * Final plane updates: Give each plane a chance to complete all
         *                      required writes/flushing before crtc's "flush
         *                      everything" call below.
         */
        drm_atomic_crtc_for_each_plane(plane, crtc) {
                if (dpu_crtc->smmu_state.transition_error)
                        dpu_plane_set_error(plane, true);
                dpu_plane_flush(plane);
        }

        /* Kickoff will be scheduled by outer layer */
}

/**
 * dpu_crtc_destroy_state - state destroy hook
 * @crtc: drm CRTC
 * @state: CRTC state object to release
 */
static void dpu_crtc_destroy_state(struct drm_crtc *crtc,
                struct drm_crtc_state *state)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_crtc_state *cstate;

        if (!crtc || !state) {
                DPU_ERROR("invalid argument(s)\n");
                return;
        }

        dpu_crtc = to_dpu_crtc(crtc);
        cstate = to_dpu_crtc_state(state);

        DPU_DEBUG("crtc%d\n", crtc->base.id);

        __drm_atomic_helper_crtc_destroy_state(state);

        kfree(cstate);
}

static int _dpu_crtc_wait_for_frame_done(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        int ret, rc = 0;

        if (!atomic_read(&dpu_crtc->frame_pending)) {
                DPU_DEBUG("no frames pending\n");
                return 0;
        }

        DPU_ATRACE_BEGIN("frame done completion wait");
        ret = wait_for_completion_timeout(&dpu_crtc->frame_done_comp,
                        msecs_to_jiffies(DPU_CRTC_FRAME_DONE_TIMEOUT_MS));
        if (!ret) {
                DRM_ERROR("frame done wait timed out, ret:%d\n", ret);
                rc = -ETIMEDOUT;
        }
        DPU_ATRACE_END("frame done completion wait");

        return rc;
}

void dpu_crtc_commit_kickoff(struct drm_crtc *crtc)
{
        struct drm_encoder *encoder;
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        struct dpu_kms *dpu_kms = _dpu_crtc_get_kms(crtc);
        struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc->state);

        /*
         * If no mixers has been allocated in dpu_crtc_atomic_check(),
         * it means we are trying to start a CRTC whose state is disabled:
         * nothing else needs to be done.
         */
        if (unlikely(!cstate->num_mixers))
                return;

        DPU_ATRACE_BEGIN("crtc_commit");

        /*
         * Encoder will flush/start now, unless it has a tx pending. If so, it
         * may delay and flush at an irq event (e.g. ppdone)
         */
        drm_for_each_encoder_mask(encoder, crtc->dev,
                                  crtc->state->encoder_mask)
                dpu_encoder_prepare_for_kickoff(encoder);

        if (atomic_inc_return(&dpu_crtc->frame_pending) == 1) {
                /* acquire bandwidth and other resources */
                DPU_DEBUG("crtc%d first commit\n", crtc->base.id);
        } else
                DPU_DEBUG("crtc%d commit\n", crtc->base.id);

        dpu_crtc->play_count++;

        dpu_vbif_clear_errors(dpu_kms);

        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
                dpu_encoder_kickoff(encoder);

        reinit_completion(&dpu_crtc->frame_done_comp);
        DPU_ATRACE_END("crtc_commit");
}

static void dpu_crtc_reset(struct drm_crtc *crtc)
{
        struct dpu_crtc_state *cstate = kzalloc(sizeof(*cstate), GFP_KERNEL);

        if (crtc->state)
                dpu_crtc_destroy_state(crtc, crtc->state);

        __drm_atomic_helper_crtc_reset(crtc, &cstate->base);
}

/**
 * dpu_crtc_duplicate_state - state duplicate hook
 * @crtc: Pointer to drm crtc structure
 * @Returns: Pointer to new drm_crtc_state structure
 */
static struct drm_crtc_state *dpu_crtc_duplicate_state(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_crtc_state *cstate, *old_cstate;

        if (!crtc || !crtc->state) {
                DPU_ERROR("invalid argument(s)\n");
                return NULL;
        }

        dpu_crtc = to_dpu_crtc(crtc);
        old_cstate = to_dpu_crtc_state(crtc->state);
        cstate = kmemdup(old_cstate, sizeof(*old_cstate), GFP_KERNEL);
        if (!cstate) {
                DPU_ERROR("failed to allocate state\n");
                return NULL;
        }

        /* duplicate base helper */
        __drm_atomic_helper_crtc_duplicate_state(crtc, &cstate->base);

        return &cstate->base;
}

static void dpu_crtc_disable(struct drm_crtc *crtc,
                             struct drm_crtc_state *old_crtc_state)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_crtc_state *cstate;
        struct drm_display_mode *mode;
        struct drm_encoder *encoder;
        struct msm_drm_private *priv;
        unsigned long flags;
        bool release_bandwidth = false;

        if (!crtc || !crtc->state) {
                DPU_ERROR("invalid crtc\n");
                return;
        }
        dpu_crtc = to_dpu_crtc(crtc);
        cstate = to_dpu_crtc_state(crtc->state);
        mode = &cstate->base.adjusted_mode;
        priv = crtc->dev->dev_private;

        DRM_DEBUG_KMS("crtc%d\n", crtc->base.id);

        /* Disable/save vblank irq handling */
        drm_crtc_vblank_off(crtc);

        drm_for_each_encoder_mask(encoder, crtc->dev,
                                  old_crtc_state->encoder_mask) {
                /* in video mode, we hold an extra bandwidth reference
                 * as we cannot drop bandwidth at frame-done if any
                 * crtc is being used in video mode.
                 */
                if (dpu_encoder_get_intf_mode(encoder) == INTF_MODE_VIDEO)
                        release_bandwidth = true;
                dpu_encoder_assign_crtc(encoder, NULL);
        }

        /* wait for frame_event_done completion */
        if (_dpu_crtc_wait_for_frame_done(crtc))
                DPU_ERROR("crtc%d wait for frame done failed;frame_pending%d\n",
                                crtc->base.id,
                                atomic_read(&dpu_crtc->frame_pending));

        trace_dpu_crtc_disable(DRMID(crtc), false, dpu_crtc);
        dpu_crtc->enabled = false;

        if (atomic_read(&dpu_crtc->frame_pending)) {
                trace_dpu_crtc_disable_frame_pending(DRMID(crtc),
                                     atomic_read(&dpu_crtc->frame_pending));
                if (release_bandwidth)
                        dpu_core_perf_crtc_release_bw(crtc);
                atomic_set(&dpu_crtc->frame_pending, 0);
        }

        dpu_core_perf_crtc_update(crtc, 0, true);

        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
                dpu_encoder_register_frame_event_callback(encoder, NULL, NULL);

        memset(cstate->mixers, 0, sizeof(cstate->mixers));
        cstate->num_mixers = 0;

        /* disable clk & bw control until clk & bw properties are set */
        cstate->bw_control = false;
        cstate->bw_split_vote = false;

        if (crtc->state->event && !crtc->state->active) {
                spin_lock_irqsave(&crtc->dev->event_lock, flags);
                drm_crtc_send_vblank_event(crtc, crtc->state->event);
                crtc->state->event = NULL;
                spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
        }

        pm_runtime_put_sync(crtc->dev->dev);
}

static void dpu_crtc_enable(struct drm_crtc *crtc,
                struct drm_crtc_state *old_crtc_state)
{
        struct dpu_crtc *dpu_crtc;
        struct drm_encoder *encoder;
        struct msm_drm_private *priv;
        bool request_bandwidth;

        if (!crtc) {
                DPU_ERROR("invalid crtc\n");
                return;
        }
        priv = crtc->dev->dev_private;

        pm_runtime_get_sync(crtc->dev->dev);

        DRM_DEBUG_KMS("crtc%d\n", crtc->base.id);
        dpu_crtc = to_dpu_crtc(crtc);

        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask) {
                /* in video mode, we hold an extra bandwidth reference
                 * as we cannot drop bandwidth at frame-done if any
                 * crtc is being used in video mode.
                 */
                if (dpu_encoder_get_intf_mode(encoder) == INTF_MODE_VIDEO)
                        request_bandwidth = true;
                dpu_encoder_register_frame_event_callback(encoder,
                                dpu_crtc_frame_event_cb, (void *)crtc);
        }

        if (request_bandwidth)
                atomic_inc(&_dpu_crtc_get_kms(crtc)->bandwidth_ref);

        trace_dpu_crtc_enable(DRMID(crtc), true, dpu_crtc);
        dpu_crtc->enabled = true;

        drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
                dpu_encoder_assign_crtc(encoder, crtc);

        /* Enable/restore vblank irq handling */
        drm_crtc_vblank_on(crtc);
}

struct plane_state {
        struct dpu_plane_state *dpu_pstate;
        const struct drm_plane_state *drm_pstate;
        int stage;
        u32 pipe_id;
};

static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
                struct drm_crtc_state *state)
{
        struct dpu_crtc *dpu_crtc;
        struct plane_state *pstates;
        struct dpu_crtc_state *cstate;

        const struct drm_plane_state *pstate;
        struct drm_plane *plane;
        struct drm_display_mode *mode;

        int cnt = 0, rc = 0, mixer_width, i, z_pos;

        struct dpu_multirect_plane_states multirect_plane[DPU_STAGE_MAX * 2];
        int multirect_count = 0;
        const struct drm_plane_state *pipe_staged[SSPP_MAX];
        int left_zpos_cnt = 0, right_zpos_cnt = 0;
        struct drm_rect crtc_rect = { 0 };

        if (!crtc) {
                DPU_ERROR("invalid crtc\n");
                return -EINVAL;
        }

        pstates = kzalloc(sizeof(*pstates) * DPU_STAGE_MAX * 4, GFP_KERNEL);

        dpu_crtc = to_dpu_crtc(crtc);
        cstate = to_dpu_crtc_state(state);

        if (!state->enable || !state->active) {
                DPU_DEBUG("crtc%d -> enable %d, active %d, skip atomic_check\n",
                                crtc->base.id, state->enable, state->active);
                goto end;
        }

        mode = &state->adjusted_mode;
        DPU_DEBUG("%s: check", dpu_crtc->name);

        /* force a full mode set if active state changed */
        if (state->active_changed)
                state->mode_changed = true;

        memset(pipe_staged, 0, sizeof(pipe_staged));

        mixer_width = mode->hdisplay / cstate->num_mixers;

        _dpu_crtc_setup_lm_bounds(crtc, state);

        crtc_rect.x2 = mode->hdisplay;
        crtc_rect.y2 = mode->vdisplay;

         /* get plane state for all drm planes associated with crtc state */
        drm_atomic_crtc_state_for_each_plane_state(plane, pstate, state) {
                struct drm_rect dst, clip = crtc_rect;

                if (IS_ERR_OR_NULL(pstate)) {
                        rc = PTR_ERR(pstate);
                        DPU_ERROR("%s: failed to get plane%d state, %d\n",
                                        dpu_crtc->name, plane->base.id, rc);
                        goto end;
                }
                if (cnt >= DPU_STAGE_MAX * 4)
                        continue;

                pstates[cnt].dpu_pstate = to_dpu_plane_state(pstate);
                pstates[cnt].drm_pstate = pstate;
                pstates[cnt].stage = pstate->normalized_zpos;
                pstates[cnt].pipe_id = dpu_plane_pipe(plane);

                if (pipe_staged[pstates[cnt].pipe_id]) {
                        multirect_plane[multirect_count].r0 =
                                pipe_staged[pstates[cnt].pipe_id];
                        multirect_plane[multirect_count].r1 = pstate;
                        multirect_count++;

                        pipe_staged[pstates[cnt].pipe_id] = NULL;
                } else {
                        pipe_staged[pstates[cnt].pipe_id] = pstate;
                }

                cnt++;

                dst = drm_plane_state_dest(pstate);
                if (!drm_rect_intersect(&clip, &dst)) {
                        DPU_ERROR("invalid vertical/horizontal destination\n");
                        DPU_ERROR("display: " DRM_RECT_FMT " plane: "
                                  DRM_RECT_FMT "\n", DRM_RECT_ARG(&crtc_rect),
                                  DRM_RECT_ARG(&dst));
                        rc = -E2BIG;
                        goto end;
                }
        }

        for (i = 1; i < SSPP_MAX; i++) {
                if (pipe_staged[i]) {
                        dpu_plane_clear_multirect(pipe_staged[i]);

                        if (is_dpu_plane_virtual(pipe_staged[i]->plane)) {
                                DPU_ERROR(
                                        "r1 only virt plane:%d not supported\n",
                                        pipe_staged[i]->plane->base.id);
                                rc  = -EINVAL;
                                goto end;
                        }
                }
        }

        z_pos = -1;
        for (i = 0; i < cnt; i++) {
                /* reset counts at every new blend stage */
                if (pstates[i].stage != z_pos) {
                        left_zpos_cnt = 0;
                        right_zpos_cnt = 0;
                        z_pos = pstates[i].stage;
                }

                /* verify z_pos setting before using it */
                if (z_pos >= DPU_STAGE_MAX - DPU_STAGE_0) {
                        DPU_ERROR("> %d plane stages assigned\n",
                                        DPU_STAGE_MAX - DPU_STAGE_0);
                        rc = -EINVAL;
                        goto end;
                } else if (pstates[i].drm_pstate->crtc_x < mixer_width) {
                        if (left_zpos_cnt == 2) {
                                DPU_ERROR("> 2 planes @ stage %d on left\n",
                                        z_pos);
                                rc = -EINVAL;
                                goto end;
                        }
                        left_zpos_cnt++;

                } else {
                        if (right_zpos_cnt == 2) {
                                DPU_ERROR("> 2 planes @ stage %d on right\n",
                                        z_pos);
                                rc = -EINVAL;
                                goto end;
                        }
                        right_zpos_cnt++;
                }

                pstates[i].dpu_pstate->stage = z_pos + DPU_STAGE_0;
                DPU_DEBUG("%s: zpos %d", dpu_crtc->name, z_pos);
        }

        for (i = 0; i < multirect_count; i++) {
                if (dpu_plane_validate_multirect_v2(&multirect_plane[i])) {
                        DPU_ERROR(
                        "multirect validation failed for planes (%d - %d)\n",
                                        multirect_plane[i].r0->plane->base.id,
                                        multirect_plane[i].r1->plane->base.id);
                        rc = -EINVAL;
                        goto end;
                }
        }

        atomic_inc(&_dpu_crtc_get_kms(crtc)->bandwidth_ref);

        rc = dpu_core_perf_crtc_check(crtc, state);
        if (rc) {
                DPU_ERROR("crtc%d failed performance check %d\n",
                                crtc->base.id, rc);
                goto end;
        }

        /* validate source split:
         * use pstates sorted by stage to check planes on same stage
         * we assume that all pipes are in source split so its valid to compare
         * without taking into account left/right mixer placement
         */
        for (i = 1; i < cnt; i++) {
                struct plane_state *prv_pstate, *cur_pstate;
                struct drm_rect left_rect, right_rect;
                int32_t left_pid, right_pid;
                int32_t stage;

                prv_pstate = &pstates[i - 1];
                cur_pstate = &pstates[i];
                if (prv_pstate->stage != cur_pstate->stage)
                        continue;

                stage = cur_pstate->stage;

                left_pid = prv_pstate->dpu_pstate->base.plane->base.id;
                left_rect = drm_plane_state_dest(prv_pstate->drm_pstate);

                right_pid = cur_pstate->dpu_pstate->base.plane->base.id;
                right_rect = drm_plane_state_dest(cur_pstate->drm_pstate);

                if (right_rect.x1 < left_rect.x1) {
                        swap(left_pid, right_pid);
                        swap(left_rect, right_rect);
                }

                /**
                 * - planes are enumerated in pipe-priority order such that
                 *   planes with lower drm_id must be left-most in a shared
                 *   blend-stage when using source split.
                 * - planes in source split must be contiguous in width
                 * - planes in source split must have same dest yoff and height
                 */
                if (right_pid < left_pid) {
                        DPU_ERROR(
                                "invalid src split cfg. priority mismatch. stage: %d left: %d right: %d\n",
                                stage, left_pid, right_pid);
                        rc = -EINVAL;
                        goto end;
                } else if (right_rect.x1 != drm_rect_width(&left_rect)) {
                        DPU_ERROR("non-contiguous coordinates for src split. "
                                  "stage: %d left: " DRM_RECT_FMT " right: "
                                  DRM_RECT_FMT "\n", stage,
                                  DRM_RECT_ARG(&left_rect),
                                  DRM_RECT_ARG(&right_rect));
                        rc = -EINVAL;
                        goto end;
                } else if (left_rect.y1 != right_rect.y1 ||
                           drm_rect_height(&left_rect) != drm_rect_height(&right_rect)) {
                        DPU_ERROR("source split at stage: %d. invalid "
                                  "yoff/height: left: " DRM_RECT_FMT " right: "
                                  DRM_RECT_FMT "\n", stage,
                                  DRM_RECT_ARG(&left_rect),
                                  DRM_RECT_ARG(&right_rect));
                        rc = -EINVAL;
                        goto end;
                }
        }

end:
        kfree(pstates);
        return rc;
}

int dpu_crtc_vblank(struct drm_crtc *crtc, bool en)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        struct drm_encoder *enc;

        trace_dpu_crtc_vblank(DRMID(&dpu_crtc->base), en, dpu_crtc);

        /*
         * Normally we would iterate through encoder_mask in crtc state to find
         * attached encoders. In this case, we might be disabling vblank _after_
         * encoder_mask has been cleared.
         *
         * Instead, we "assign" a crtc to the encoder in enable and clear it in
         * disable (which is also after encoder_mask is cleared). So instead of
         * using encoder mask, we'll ask the encoder to toggle itself iff it's
         * currently assigned to our crtc.
         *
         * Note also that this function cannot be called while crtc is disabled
         * since we use drm_crtc_vblank_on/off. So we don't need to worry
         * about the assigned crtcs being inconsistent with the current state
         * (which means no need to worry about modeset locks).
         */
        list_for_each_entry(enc, &crtc->dev->mode_config.encoder_list, head) {
                trace_dpu_crtc_vblank_enable(DRMID(crtc), DRMID(enc), en,
                                             dpu_crtc);

                dpu_encoder_toggle_vblank_for_crtc(enc, crtc, en);
        }

        return 0;
}

#ifdef CONFIG_DEBUG_FS
static int _dpu_debugfs_status_show(struct seq_file *s, void *data)
{
        struct dpu_crtc *dpu_crtc;
        struct dpu_plane_state *pstate = NULL;
        struct dpu_crtc_mixer *m;

        struct drm_crtc *crtc;
        struct drm_plane *plane;
        struct drm_display_mode *mode;
        struct drm_framebuffer *fb;
        struct drm_plane_state *state;
        struct dpu_crtc_state *cstate;

        int i, out_width;

        dpu_crtc = s->private;
        crtc = &dpu_crtc->base;

        drm_modeset_lock_all(crtc->dev);
        cstate = to_dpu_crtc_state(crtc->state);

        mode = &crtc->state->adjusted_mode;
        out_width = mode->hdisplay / cstate->num_mixers;

        seq_printf(s, "crtc:%d width:%d height:%d\n", crtc->base.id,
                                mode->hdisplay, mode->vdisplay);

        seq_puts(s, "\n");

        for (i = 0; i < cstate->num_mixers; ++i) {
                m = &cstate->mixers[i];
                seq_printf(s, "\tmixer:%d ctl:%d width:%d height:%d\n",
                        m->hw_lm->idx - LM_0, m->lm_ctl->idx - CTL_0,
                        out_width, mode->vdisplay);
        }

        seq_puts(s, "\n");

        drm_atomic_crtc_for_each_plane(plane, crtc) {
                pstate = to_dpu_plane_state(plane->state);
                state = plane->state;

                if (!pstate || !state)
                        continue;

                seq_printf(s, "\tplane:%u stage:%d\n", plane->base.id,
                        pstate->stage);

                if (plane->state->fb) {
                        fb = plane->state->fb;

                        seq_printf(s, "\tfb:%d image format:%4.4s wxh:%ux%u ",
                                fb->base.id, (char *) &fb->format->format,
                                fb->width, fb->height);
                        for (i = 0; i < ARRAY_SIZE(fb->format->cpp); ++i)
                                seq_printf(s, "cpp[%d]:%u ",
                                                i, fb->format->cpp[i]);
                        seq_puts(s, "\n\t");

                        seq_printf(s, "modifier:%8llu ", fb->modifier);
                        seq_puts(s, "\n");

                        seq_puts(s, "\t");
                        for (i = 0; i < ARRAY_SIZE(fb->pitches); i++)
                                seq_printf(s, "pitches[%d]:%8u ", i,
                                                        fb->pitches[i]);
                        seq_puts(s, "\n");

                        seq_puts(s, "\t");
                        for (i = 0; i < ARRAY_SIZE(fb->offsets); i++)
                                seq_printf(s, "offsets[%d]:%8u ", i,
                                                        fb->offsets[i]);
                        seq_puts(s, "\n");
                }

                seq_printf(s, "\tsrc_x:%4d src_y:%4d src_w:%4d src_h:%4d\n",
                        state->src_x, state->src_y, state->src_w, state->src_h);

                seq_printf(s, "\tdst x:%4d dst_y:%4d dst_w:%4d dst_h:%4d\n",
                        state->crtc_x, state->crtc_y, state->crtc_w,
                        state->crtc_h);
                seq_printf(s, "\tmultirect: mode: %d index: %d\n",
                        pstate->multirect_mode, pstate->multirect_index);

                seq_puts(s, "\n");
        }
        if (dpu_crtc->vblank_cb_count) {
                ktime_t diff = ktime_sub(ktime_get(), dpu_crtc->vblank_cb_time);
                s64 diff_ms = ktime_to_ms(diff);
                s64 fps = diff_ms ? div_s64(
                                dpu_crtc->vblank_cb_count * 1000, diff_ms) : 0;

                seq_printf(s,
                        "vblank fps:%lld count:%u total:%llums total_framecount:%llu\n",
                                fps, dpu_crtc->vblank_cb_count,
                                ktime_to_ms(diff), dpu_crtc->play_count);

                /* reset time & count for next measurement */
                dpu_crtc->vblank_cb_count = 0;
                dpu_crtc->vblank_cb_time = ktime_set(0, 0);
        }

        drm_modeset_unlock_all(crtc->dev);

        return 0;
}

static int _dpu_debugfs_status_open(struct inode *inode, struct file *file)
{
        return single_open(file, _dpu_debugfs_status_show, inode->i_private);
}

#define DEFINE_DPU_DEBUGFS_SEQ_FOPS(__prefix)                          \
static int __prefix ## _open(struct inode *inode, struct file *file)    \
{                                                                       \
        return single_open(file, __prefix ## _show, inode->i_private);  \
}                                                                       \
static const struct file_operations __prefix ## _fops = {               \
        .owner = THIS_MODULE,                                           \
        .open = __prefix ## _open,                                      \
        .release = single_release,                                      \
        .read = seq_read,                                               \
        .llseek = seq_lseek,                                            \
}

static int dpu_crtc_debugfs_state_show(struct seq_file *s, void *v)
{
        struct drm_crtc *crtc = (struct drm_crtc *) s->private;
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);

        seq_printf(s, "client type: %d\n", dpu_crtc_get_client_type(crtc));
        seq_printf(s, "intf_mode: %d\n", dpu_crtc_get_intf_mode(crtc));
        seq_printf(s, "core_clk_rate: %llu\n",
                        dpu_crtc->cur_perf.core_clk_rate);
        seq_printf(s, "bw_ctl: %llu\n", dpu_crtc->cur_perf.bw_ctl);
        seq_printf(s, "max_per_pipe_ib: %llu\n",
                                dpu_crtc->cur_perf.max_per_pipe_ib);

        return 0;
}
DEFINE_DPU_DEBUGFS_SEQ_FOPS(dpu_crtc_debugfs_state);

static int _dpu_crtc_init_debugfs(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);

        static const struct file_operations debugfs_status_fops = {
                .open =         _dpu_debugfs_status_open,
                .read =         seq_read,
                .llseek =       seq_lseek,
                .release =      single_release,
        };

        dpu_crtc->debugfs_root = debugfs_create_dir(dpu_crtc->name,
                        crtc->dev->primary->debugfs_root);

        debugfs_create_file("status", 0400,
                        dpu_crtc->debugfs_root,
                        dpu_crtc, &debugfs_status_fops);
        debugfs_create_file("state", 0600,
                        dpu_crtc->debugfs_root,
                        &dpu_crtc->base,
                        &dpu_crtc_debugfs_state_fops);

        return 0;
}
#else
static int _dpu_crtc_init_debugfs(struct drm_crtc *crtc)
{
        return 0;
}
#endif /* CONFIG_DEBUG_FS */

static int dpu_crtc_late_register(struct drm_crtc *crtc)
{
        return _dpu_crtc_init_debugfs(crtc);
}

static void dpu_crtc_early_unregister(struct drm_crtc *crtc)
{
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);

        debugfs_remove_recursive(dpu_crtc->debugfs_root);
}

static const struct drm_crtc_funcs dpu_crtc_funcs = {
        .set_config = drm_atomic_helper_set_config,
        .destroy = dpu_crtc_destroy,
        .page_flip = drm_atomic_helper_page_flip,
        .reset = dpu_crtc_reset,
        .atomic_duplicate_state = dpu_crtc_duplicate_state,
        .atomic_destroy_state = dpu_crtc_destroy_state,
        .late_register = dpu_crtc_late_register,
        .early_unregister = dpu_crtc_early_unregister,
};

static const struct drm_crtc_helper_funcs dpu_crtc_helper_funcs = {
        .atomic_disable = dpu_crtc_disable,
        .atomic_enable = dpu_crtc_enable,
        .atomic_check = dpu_crtc_atomic_check,
        .atomic_begin = dpu_crtc_atomic_begin,
        .atomic_flush = dpu_crtc_atomic_flush,
};

/* initialize crtc */
struct drm_crtc *dpu_crtc_init(struct drm_device *dev, struct drm_plane *plane,
                                struct drm_plane *cursor)
{
        struct drm_crtc *crtc = NULL;
        struct dpu_crtc *dpu_crtc = NULL;
        int i;

        dpu_crtc = kzalloc(sizeof(*dpu_crtc), GFP_KERNEL);
        if (!dpu_crtc)
                return ERR_PTR(-ENOMEM);

        crtc = &dpu_crtc->base;
        crtc->dev = dev;

        spin_lock_init(&dpu_crtc->spin_lock);
        atomic_set(&dpu_crtc->frame_pending, 0);

        init_completion(&dpu_crtc->frame_done_comp);

        INIT_LIST_HEAD(&dpu_crtc->frame_event_list);

        for (i = 0; i < ARRAY_SIZE(dpu_crtc->frame_events); i++) {
                INIT_LIST_HEAD(&dpu_crtc->frame_events[i].list);
                list_add(&dpu_crtc->frame_events[i].list,
                                &dpu_crtc->frame_event_list);
                kthread_init_work(&dpu_crtc->frame_events[i].work,
                                dpu_crtc_frame_event_work);
        }

        drm_crtc_init_with_planes(dev, crtc, plane, cursor, &dpu_crtc_funcs,
                                NULL);

        drm_crtc_helper_add(crtc, &dpu_crtc_helper_funcs);

        /* save user friendly CRTC name for later */
        snprintf(dpu_crtc->name, DPU_CRTC_NAME_SIZE, "crtc%u", crtc->base.id);

        /* initialize event handling */
        spin_lock_init(&dpu_crtc->event_lock);

        DPU_DEBUG("%s: successfully initialized crtc\n", dpu_crtc->name);
        return crtc;
}