// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2015 MediaTek Inc.
 */

#include <asm/barrier.h>
#include <drm/drmP.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_probe_helper.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <soc/mediatek/smi.h>

#include "mtk_drm_drv.h"
#include "mtk_drm_crtc.h"
#include "mtk_drm_ddp.h"
#include "mtk_drm_ddp_comp.h"
#include "mtk_drm_gem.h"
#include "mtk_drm_plane.h"

/**
 * struct mtk_drm_crtc - MediaTek specific crtc structure.
 * @base: crtc object.
 * @enabled: records whether crtc_enable succeeded
 * @planes: array of 4 drm_plane structures, one for each overlay plane
 * @pending_planes: whether any plane has pending changes to be applied
 * @config_regs: memory mapped mmsys configuration register space
 * @mutex: handle to one of the ten disp_mutex streams
 * @ddp_comp_nr: number of components in ddp_comp
 * @ddp_comp: array of pointers the mtk_ddp_comp structures used by this crtc
 */
struct mtk_drm_crtc {
        struct drm_crtc                 base;
        bool                            enabled;

        bool                            pending_needs_vblank;
        struct drm_pending_vblank_event *event;

        struct drm_plane                *planes;
        unsigned int                    layer_nr;
        bool                            pending_planes;

        void __iomem                    *config_regs;
        struct mtk_disp_mutex           *mutex;
        unsigned int                    ddp_comp_nr;
        struct mtk_ddp_comp             **ddp_comp;
};

struct mtk_crtc_state {
        struct drm_crtc_state           base;

        bool                            pending_config;
        unsigned int                    pending_width;
        unsigned int                    pending_height;
        unsigned int                    pending_vrefresh;
};

static inline struct mtk_drm_crtc *to_mtk_crtc(struct drm_crtc *c)
{
        return container_of(c, struct mtk_drm_crtc, base);
}

static inline struct mtk_crtc_state *to_mtk_crtc_state(struct drm_crtc_state *s)
{
        return container_of(s, struct mtk_crtc_state, base);
}

static void mtk_drm_crtc_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
{
        struct drm_crtc *crtc = &mtk_crtc->base;
        unsigned long flags;

        spin_lock_irqsave(&crtc->dev->event_lock, flags);
        drm_crtc_send_vblank_event(crtc, mtk_crtc->event);
        drm_crtc_vblank_put(crtc);
        mtk_crtc->event = NULL;
        spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
}

static void mtk_drm_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
{
        drm_crtc_handle_vblank(&mtk_crtc->base);
        if (mtk_crtc->pending_needs_vblank) {
                mtk_drm_crtc_finish_page_flip(mtk_crtc);
                mtk_crtc->pending_needs_vblank = false;
        }
}

static void mtk_drm_crtc_destroy(struct drm_crtc *crtc)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);

        mtk_disp_mutex_put(mtk_crtc->mutex);

        drm_crtc_cleanup(crtc);
}

static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
{
        struct mtk_crtc_state *state;

        if (crtc->state) {
                __drm_atomic_helper_crtc_destroy_state(crtc->state);

                state = to_mtk_crtc_state(crtc->state);
                memset(state, 0, sizeof(*state));
        } else {
                state = kzalloc(sizeof(*state), GFP_KERNEL);
                if (!state)
                        return;
                crtc->state = &state->base;
        }

        state->base.crtc = crtc;
}

static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc *crtc)
{
        struct mtk_crtc_state *state;

        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (!state)
                return NULL;

        __drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);

        WARN_ON(state->base.crtc != crtc);
        state->base.crtc = crtc;

        return &state->base;
}

static void mtk_drm_crtc_destroy_state(struct drm_crtc *crtc,
                                       struct drm_crtc_state *state)
{
        __drm_atomic_helper_crtc_destroy_state(state);
        kfree(to_mtk_crtc_state(state));
}

static bool mtk_drm_crtc_mode_fixup(struct drm_crtc *crtc,
                                    const struct drm_display_mode *mode,
                                    struct drm_display_mode *adjusted_mode)
{
        /* Nothing to do here, but this callback is mandatory. */
        return true;
}

static void mtk_drm_crtc_mode_set_nofb(struct drm_crtc *crtc)
{
        struct mtk_crtc_state *state = to_mtk_crtc_state(crtc->state);

        state->pending_width = crtc->mode.hdisplay;
        state->pending_height = crtc->mode.vdisplay;
        state->pending_vrefresh = crtc->mode.vrefresh;
        wmb();  /* Make sure the above parameters are set before update */
        state->pending_config = true;
}

static int mtk_drm_crtc_enable_vblank(struct drm_crtc *crtc)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];

        mtk_ddp_comp_enable_vblank(comp, &mtk_crtc->base);

        return 0;
}

static void mtk_drm_crtc_disable_vblank(struct drm_crtc *crtc)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];

        mtk_ddp_comp_disable_vblank(comp);
}

static int mtk_crtc_ddp_clk_enable(struct mtk_drm_crtc *mtk_crtc)
{
        int ret;
        int i;

        DRM_DEBUG_DRIVER("%s\n", __func__);
        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
                ret = clk_prepare_enable(mtk_crtc->ddp_comp[i]->clk);
                if (ret) {
                        DRM_ERROR("Failed to enable clock %d: %d\n", i, ret);
                        goto err;
                }
        }

        return 0;
err:
        while (--i >= 0)
                clk_disable_unprepare(mtk_crtc->ddp_comp[i]->clk);
        return ret;
}

static void mtk_crtc_ddp_clk_disable(struct mtk_drm_crtc *mtk_crtc)
{
        int i;

        DRM_DEBUG_DRIVER("%s\n", __func__);
        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
                clk_disable_unprepare(mtk_crtc->ddp_comp[i]->clk);
}

static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
{
        struct drm_crtc *crtc = &mtk_crtc->base;
        struct drm_connector *connector;
        struct drm_encoder *encoder;
        struct drm_connector_list_iter conn_iter;
        unsigned int width, height, vrefresh, bpc = MTK_MAX_BPC;
        int ret;
        int i;

        DRM_DEBUG_DRIVER("%s\n", __func__);
        if (WARN_ON(!crtc->state))
                return -EINVAL;

        width = crtc->state->adjusted_mode.hdisplay;
        height = crtc->state->adjusted_mode.vdisplay;
        vrefresh = crtc->state->adjusted_mode.vrefresh;

        drm_for_each_encoder(encoder, crtc->dev) {
                if (encoder->crtc != crtc)
                        continue;

                drm_connector_list_iter_begin(crtc->dev, &conn_iter);
                drm_for_each_connector_iter(connector, &conn_iter) {
                        if (connector->encoder != encoder)
                                continue;
                        if (connector->display_info.bpc != 0 &&
                            bpc > connector->display_info.bpc)
                                bpc = connector->display_info.bpc;
                }
                drm_connector_list_iter_end(&conn_iter);
        }

        ret = pm_runtime_get_sync(crtc->dev->dev);
        if (ret < 0) {
                DRM_ERROR("Failed to enable power domain: %d\n", ret);
                return ret;
        }

        ret = mtk_disp_mutex_prepare(mtk_crtc->mutex);
        if (ret < 0) {
                DRM_ERROR("Failed to enable mutex clock: %d\n", ret);
                goto err_pm_runtime_put;
        }

        ret = mtk_crtc_ddp_clk_enable(mtk_crtc);
        if (ret < 0) {
                DRM_ERROR("Failed to enable component clocks: %d\n", ret);
                goto err_mutex_unprepare;
        }

        DRM_DEBUG_DRIVER("mediatek_ddp_ddp_path_setup\n");
        for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
                mtk_ddp_add_comp_to_path(mtk_crtc->config_regs,
                                         mtk_crtc->ddp_comp[i]->id,
                                         mtk_crtc->ddp_comp[i + 1]->id);
                mtk_disp_mutex_add_comp(mtk_crtc->mutex,
                                        mtk_crtc->ddp_comp[i]->id);
        }
        mtk_disp_mutex_add_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
        mtk_disp_mutex_enable(mtk_crtc->mutex);

        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
                struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[i];

                mtk_ddp_comp_config(comp, width, height, vrefresh, bpc);
                mtk_ddp_comp_start(comp);
        }

        /* Initially configure all planes */
        for (i = 0; i < mtk_crtc->layer_nr; i++) {
                struct drm_plane *plane = &mtk_crtc->planes[i];
                struct mtk_plane_state *plane_state;

                plane_state = to_mtk_plane_state(plane->state);
                mtk_ddp_comp_layer_config(mtk_crtc->ddp_comp[0], i,
                                          plane_state);
        }

        return 0;

err_mutex_unprepare:
        mtk_disp_mutex_unprepare(mtk_crtc->mutex);
err_pm_runtime_put:
        pm_runtime_put(crtc->dev->dev);
        return ret;
}

static void mtk_crtc_ddp_hw_fini(struct mtk_drm_crtc *mtk_crtc)
{
        struct drm_device *drm = mtk_crtc->base.dev;
        int i;

        DRM_DEBUG_DRIVER("%s\n", __func__);
        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
                mtk_ddp_comp_stop(mtk_crtc->ddp_comp[i]);
        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
                mtk_disp_mutex_remove_comp(mtk_crtc->mutex,
                                           mtk_crtc->ddp_comp[i]->id);
        mtk_disp_mutex_disable(mtk_crtc->mutex);
        for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
                mtk_ddp_remove_comp_from_path(mtk_crtc->config_regs,
                                              mtk_crtc->ddp_comp[i]->id,
                                              mtk_crtc->ddp_comp[i + 1]->id);
                mtk_disp_mutex_remove_comp(mtk_crtc->mutex,
                                           mtk_crtc->ddp_comp[i]->id);
        }
        mtk_disp_mutex_remove_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
        mtk_crtc_ddp_clk_disable(mtk_crtc);
        mtk_disp_mutex_unprepare(mtk_crtc->mutex);

        pm_runtime_put(drm->dev);
}

static void mtk_crtc_ddp_config(struct drm_crtc *crtc)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_crtc_state *state = to_mtk_crtc_state(mtk_crtc->base.state);
        struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
        unsigned int i;

        /*
         * TODO: instead of updating the registers here, we should prepare
         * working registers in atomic_commit and let the hardware command
         * queue update module registers on vblank.
         */
        if (state->pending_config) {
                mtk_ddp_comp_config(comp, state->pending_width,
                                    state->pending_height,
                                    state->pending_vrefresh, 0);

                state->pending_config = false;
        }

        if (mtk_crtc->pending_planes) {
                for (i = 0; i < mtk_crtc->layer_nr; i++) {
                        struct drm_plane *plane = &mtk_crtc->planes[i];
                        struct mtk_plane_state *plane_state;

                        plane_state = to_mtk_plane_state(plane->state);

                        if (plane_state->pending.config) {
                                mtk_ddp_comp_layer_config(comp, i, plane_state);
                                plane_state->pending.config = false;
                        }
                }
                mtk_crtc->pending_planes = false;
        }
}

static void mtk_drm_crtc_atomic_enable(struct drm_crtc *crtc,
                                       struct drm_crtc_state *old_state)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
        int ret;

        DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);

        ret = mtk_smi_larb_get(comp->larb_dev);
        if (ret) {
                DRM_ERROR("Failed to get larb: %d\n", ret);
                return;
        }

        ret = mtk_crtc_ddp_hw_init(mtk_crtc);
        if (ret) {
                mtk_smi_larb_put(comp->larb_dev);
                return;
        }

        drm_crtc_vblank_on(crtc);
        mtk_crtc->enabled = true;
}

static void mtk_drm_crtc_atomic_disable(struct drm_crtc *crtc,
                                        struct drm_crtc_state *old_state)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
        int i;

        DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
        if (!mtk_crtc->enabled)
                return;

        /* Set all pending plane state to disabled */
        for (i = 0; i < mtk_crtc->layer_nr; i++) {
                struct drm_plane *plane = &mtk_crtc->planes[i];
                struct mtk_plane_state *plane_state;

                plane_state = to_mtk_plane_state(plane->state);
                plane_state->pending.enable = false;
                plane_state->pending.config = true;
        }
        mtk_crtc->pending_planes = true;

        /* Wait for planes to be disabled */
        drm_crtc_wait_one_vblank(crtc);

        drm_crtc_vblank_off(crtc);
        mtk_crtc_ddp_hw_fini(mtk_crtc);
        mtk_smi_larb_put(comp->larb_dev);

        mtk_crtc->enabled = false;
}

static void mtk_drm_crtc_atomic_begin(struct drm_crtc *crtc,
                                      struct drm_crtc_state *old_crtc_state)
{
        struct mtk_crtc_state *state = to_mtk_crtc_state(crtc->state);
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);

        if (mtk_crtc->event && state->base.event)
                DRM_ERROR("new event while there is still a pending event\n");

        if (state->base.event) {
                state->base.event->pipe = drm_crtc_index(crtc);
                WARN_ON(drm_crtc_vblank_get(crtc) != 0);
                mtk_crtc->event = state->base.event;
                state->base.event = NULL;
        }
}

static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
                                      struct drm_crtc_state *old_crtc_state)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_drm_private *priv = crtc->dev->dev_private;
        unsigned int pending_planes = 0;
        int i;

        if (mtk_crtc->event)
                mtk_crtc->pending_needs_vblank = true;
        for (i = 0; i < mtk_crtc->layer_nr; i++) {
                struct drm_plane *plane = &mtk_crtc->planes[i];
                struct mtk_plane_state *plane_state;

                plane_state = to_mtk_plane_state(plane->state);
                if (plane_state->pending.dirty) {
                        plane_state->pending.config = true;
                        plane_state->pending.dirty = false;
                        pending_planes |= BIT(i);
                }
        }
        if (pending_planes)
                mtk_crtc->pending_planes = true;
        if (crtc->state->color_mgmt_changed)
                for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
                        mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], crtc->state);

        if (priv->data->shadow_register) {
                mtk_disp_mutex_acquire(mtk_crtc->mutex);
                mtk_crtc_ddp_config(crtc);
                mtk_disp_mutex_release(mtk_crtc->mutex);
        }
}

static const struct drm_crtc_funcs mtk_crtc_funcs = {
        .set_config             = drm_atomic_helper_set_config,
        .page_flip              = drm_atomic_helper_page_flip,
        .destroy                = mtk_drm_crtc_destroy,
        .reset                  = mtk_drm_crtc_reset,
        .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
        .atomic_destroy_state   = mtk_drm_crtc_destroy_state,
        .gamma_set              = drm_atomic_helper_legacy_gamma_set,
        .enable_vblank          = mtk_drm_crtc_enable_vblank,
        .disable_vblank         = mtk_drm_crtc_disable_vblank,
};

static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
        .mode_fixup     = mtk_drm_crtc_mode_fixup,
        .mode_set_nofb  = mtk_drm_crtc_mode_set_nofb,
        .atomic_begin   = mtk_drm_crtc_atomic_begin,
        .atomic_flush   = mtk_drm_crtc_atomic_flush,
        .atomic_enable  = mtk_drm_crtc_atomic_enable,
        .atomic_disable = mtk_drm_crtc_atomic_disable,
};

static int mtk_drm_crtc_init(struct drm_device *drm,
                             struct mtk_drm_crtc *mtk_crtc,
                             struct drm_plane *primary,
                             struct drm_plane *cursor, unsigned int pipe)
{
        int ret;

        ret = drm_crtc_init_with_planes(drm, &mtk_crtc->base, primary, cursor,
                                        &mtk_crtc_funcs, NULL);
        if (ret)
                goto err_cleanup_crtc;

        drm_crtc_helper_add(&mtk_crtc->base, &mtk_crtc_helper_funcs);

        return 0;

err_cleanup_crtc:
        drm_crtc_cleanup(&mtk_crtc->base);
        return ret;
}

void mtk_crtc_ddp_irq(struct drm_crtc *crtc, struct mtk_ddp_comp *comp)
{
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        struct mtk_drm_private *priv = crtc->dev->dev_private;

        if (!priv->data->shadow_register)
                mtk_crtc_ddp_config(crtc);

        mtk_drm_finish_page_flip(mtk_crtc);
}

int mtk_drm_crtc_create(struct drm_device *drm_dev,
                        const enum mtk_ddp_comp_id *path, unsigned int path_len)
{
        struct mtk_drm_private *priv = drm_dev->dev_private;
        struct device *dev = drm_dev->dev;
        struct mtk_drm_crtc *mtk_crtc;
        enum drm_plane_type type;
        unsigned int zpos;
        int pipe = priv->num_pipes;
        int ret;
        int i;

        if (!path)
                return 0;

        for (i = 0; i < path_len; i++) {
                enum mtk_ddp_comp_id comp_id = path[i];
                struct device_node *node;

                node = priv->comp_node[comp_id];
                if (!node) {
                        dev_info(dev,
                                 "Not creating crtc %d because component %d is disabled or missing\n",
                                 pipe, comp_id);
                        return 0;
                }
        }

        mtk_crtc = devm_kzalloc(dev, sizeof(*mtk_crtc), GFP_KERNEL);
        if (!mtk_crtc)
                return -ENOMEM;

        mtk_crtc->config_regs = priv->config_regs;
        mtk_crtc->ddp_comp_nr = path_len;
        mtk_crtc->ddp_comp = devm_kmalloc_array(dev, mtk_crtc->ddp_comp_nr,
                                                sizeof(*mtk_crtc->ddp_comp),
                                                GFP_KERNEL);
        if (!mtk_crtc->ddp_comp)
                return -ENOMEM;

        mtk_crtc->mutex = mtk_disp_mutex_get(priv->mutex_dev, pipe);
        if (IS_ERR(mtk_crtc->mutex)) {
                ret = PTR_ERR(mtk_crtc->mutex);
                dev_err(dev, "Failed to get mutex: %d\n", ret);
                return ret;
        }

        for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
                enum mtk_ddp_comp_id comp_id = path[i];
                struct mtk_ddp_comp *comp;
                struct device_node *node;

                node = priv->comp_node[comp_id];
                comp = priv->ddp_comp[comp_id];
                if (!comp) {
                        dev_err(dev, "Component %pOF not initialized\n", node);
                        ret = -ENODEV;
                        return ret;
                }

                mtk_crtc->ddp_comp[i] = comp;
        }

        mtk_crtc->layer_nr = mtk_ddp_comp_layer_nr(mtk_crtc->ddp_comp[0]);
        mtk_crtc->planes = devm_kcalloc(dev, mtk_crtc->layer_nr,
                                        sizeof(struct drm_plane),
                                        GFP_KERNEL);

        for (zpos = 0; zpos < mtk_crtc->layer_nr; zpos++) {
                type = (zpos == 0) ? DRM_PLANE_TYPE_PRIMARY :
                                (zpos == 1) ? DRM_PLANE_TYPE_CURSOR :
                                                DRM_PLANE_TYPE_OVERLAY;
                ret = mtk_plane_init(drm_dev, &mtk_crtc->planes[zpos],
                                     BIT(pipe), type);
                if (ret)
                        return ret;
        }

        ret = mtk_drm_crtc_init(drm_dev, mtk_crtc, &mtk_crtc->planes[0],
                                mtk_crtc->layer_nr > 1 ? &mtk_crtc->planes[1] :
                                NULL, pipe);
        if (ret < 0)
                return ret;
        drm_mode_crtc_set_gamma_size(&mtk_crtc->base, MTK_LUT_SIZE);
        drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, MTK_LUT_SIZE);
        priv->num_pipes++;

        return 0;
}