// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2011 Samsung Electronics Co.Ltd
 * Authors: Joonyoung Shim <jy0922.shim@samsung.com>
 */


#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_blend.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_print.h>
#include <drm/exynos_drm.h>

#include "exynos_drm_crtc.h"
#include "exynos_drm_drv.h"
#include "exynos_drm_fb.h"
#include "exynos_drm_gem.h"
#include "exynos_drm_plane.h"

/*
 * This function is to get X or Y size shown via screen. This needs length and
 * start position of CRTC.
 *
 *      <--- length --->
 * CRTC ----------------
 *      ^ start        ^ end
 *
 * There are six cases from a to f.
 *
 *             <----- SCREEN ----->
 *             0                 last
 *   ----------|------------------|----------
 * CRTCs
 * a -------
 *        b -------
 *        c --------------------------
 *                 d --------
 *                           e -------
 *                                  f -------
 */
static int exynos_plane_get_size(int start, unsigned length, unsigned last)
{
        int end = start + length;
        int size = 0;

        if (start <= 0) {
                if (end > 0)
                        size = min_t(unsigned, end, last);
        } else if (start <= last) {
                size = min_t(unsigned, last - start, length);
        }

        return size;
}

static void exynos_plane_mode_set(struct exynos_drm_plane_state *exynos_state)
{
        struct drm_plane_state *state = &exynos_state->base;
        struct drm_crtc *crtc = state->crtc;
        struct drm_crtc_state *crtc_state =
                drm_atomic_get_new_crtc_state(state->state, crtc);
        struct drm_display_mode *mode = &crtc_state->adjusted_mode;
        int crtc_x, crtc_y;
        unsigned int crtc_w, crtc_h;
        unsigned int src_x, src_y;
        unsigned int src_w, src_h;
        unsigned int actual_w;
        unsigned int actual_h;

        /*
         * The original src/dest coordinates are stored in exynos_state->base,
         * but we want to keep another copy internal to our driver that we can
         * clip/modify ourselves.
         */

        crtc_x = state->crtc_x;
        crtc_y = state->crtc_y;
        crtc_w = state->crtc_w;
        crtc_h = state->crtc_h;

        src_x = state->src_x >> 16;
        src_y = state->src_y >> 16;
        src_w = state->src_w >> 16;
        src_h = state->src_h >> 16;

        /* set ratio */
        exynos_state->h_ratio = (src_w << 16) / crtc_w;
        exynos_state->v_ratio = (src_h << 16) / crtc_h;

        /* clip to visible area */
        actual_w = exynos_plane_get_size(crtc_x, crtc_w, mode->hdisplay);
        actual_h = exynos_plane_get_size(crtc_y, crtc_h, mode->vdisplay);

        if (crtc_x < 0) {
                if (actual_w)
                        src_x += ((-crtc_x) * exynos_state->h_ratio) >> 16;
                crtc_x = 0;
        }

        if (crtc_y < 0) {
                if (actual_h)
                        src_y += ((-crtc_y) * exynos_state->v_ratio) >> 16;
                crtc_y = 0;
        }

        /* set drm framebuffer data. */
        exynos_state->src.x = src_x;
        exynos_state->src.y = src_y;
        exynos_state->src.w = (actual_w * exynos_state->h_ratio) >> 16;
        exynos_state->src.h = (actual_h * exynos_state->v_ratio) >> 16;

        /* set plane range to be displayed. */
        exynos_state->crtc.x = crtc_x;
        exynos_state->crtc.y = crtc_y;
        exynos_state->crtc.w = actual_w;
        exynos_state->crtc.h = actual_h;

        DRM_DEV_DEBUG_KMS(crtc->dev->dev,
                          "plane : offset_x/y(%d,%d), width/height(%d,%d)",
                          exynos_state->crtc.x, exynos_state->crtc.y,
                          exynos_state->crtc.w, exynos_state->crtc.h);
}

static void exynos_drm_plane_reset(struct drm_plane *plane)
{
        struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane);
        struct exynos_drm_plane_state *exynos_state;

        if (plane->state) {
                exynos_state = to_exynos_plane_state(plane->state);
                __drm_atomic_helper_plane_destroy_state(plane->state);
                kfree(exynos_state);
                plane->state = NULL;
        }

        exynos_state = kzalloc_obj(*exynos_state);
        if (exynos_state) {
                __drm_atomic_helper_plane_reset(plane, &exynos_state->base);
                plane->state->zpos = exynos_plane->config->zpos;
        }
}

static struct drm_plane_state *
exynos_drm_plane_duplicate_state(struct drm_plane *plane)
{
        struct exynos_drm_plane_state *exynos_state;
        struct exynos_drm_plane_state *copy;

        exynos_state = to_exynos_plane_state(plane->state);
        copy = kzalloc_obj(*exynos_state);
        if (!copy)
                return NULL;

        __drm_atomic_helper_plane_duplicate_state(plane, &copy->base);
        return &copy->base;
}

static void exynos_drm_plane_destroy_state(struct drm_plane *plane,
                                           struct drm_plane_state *old_state)
{
        struct exynos_drm_plane_state *old_exynos_state =
                                        to_exynos_plane_state(old_state);
        __drm_atomic_helper_plane_destroy_state(old_state);
        kfree(old_exynos_state);
}

static struct drm_plane_funcs exynos_plane_funcs = {
        .update_plane   = drm_atomic_helper_update_plane,
        .disable_plane  = drm_atomic_helper_disable_plane,
        .destroy        = drm_plane_cleanup,
        .reset          = exynos_drm_plane_reset,
        .atomic_duplicate_state = exynos_drm_plane_duplicate_state,
        .atomic_destroy_state = exynos_drm_plane_destroy_state,
};

static int
exynos_drm_plane_check_format(const struct exynos_drm_plane_config *config,
                              struct exynos_drm_plane_state *state)
{
        struct drm_framebuffer *fb = state->base.fb;
        struct drm_device *dev = fb->dev;

        switch (fb->modifier) {
        case DRM_FORMAT_MOD_SAMSUNG_64_32_TILE:
                if (!(config->capabilities & EXYNOS_DRM_PLANE_CAP_TILE))
                        return -ENOTSUPP;
                break;

        case DRM_FORMAT_MOD_LINEAR:
                break;

        default:
                DRM_DEV_ERROR(dev->dev, "unsupported pixel format modifier");
                return -ENOTSUPP;
        }

        return 0;
}

static int
exynos_drm_plane_check_size(const struct exynos_drm_plane_config *config,
                            struct exynos_drm_plane_state *state)
{
        struct drm_crtc *crtc = state->base.crtc;
        bool width_ok = false, height_ok = false;

        if (config->capabilities & EXYNOS_DRM_PLANE_CAP_SCALE)
                return 0;

        if (state->src.w == state->crtc.w)
                width_ok = true;

        if (state->src.h == state->crtc.h)
                height_ok = true;

        if ((config->capabilities & EXYNOS_DRM_PLANE_CAP_DOUBLE) &&
            state->h_ratio == (1 << 15))
                width_ok = true;

        if ((config->capabilities & EXYNOS_DRM_PLANE_CAP_DOUBLE) &&
            state->v_ratio == (1 << 15))
                height_ok = true;

        if (width_ok && height_ok)
                return 0;

        DRM_DEV_DEBUG_KMS(crtc->dev->dev, "scaling mode is not supported");
        return -ENOTSUPP;
}

static int exynos_plane_atomic_check(struct drm_plane *plane,
                                     struct drm_atomic_state *state)
{
        struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
                                                                                 plane);
        struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane);
        struct exynos_drm_plane_state *exynos_state =
                                                to_exynos_plane_state(new_plane_state);
        int ret = 0;

        if (!new_plane_state->crtc || !new_plane_state->fb)
                return 0;

        /* translate state into exynos_state */
        exynos_plane_mode_set(exynos_state);

        ret = exynos_drm_plane_check_format(exynos_plane->config, exynos_state);
        if (ret)
                return ret;

        ret = exynos_drm_plane_check_size(exynos_plane->config, exynos_state);
        return ret;
}

static void exynos_plane_atomic_update(struct drm_plane *plane,
                                       struct drm_atomic_state *state)
{
        struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
                                                                           plane);
        struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(new_state->crtc);
        struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane);

        if (!new_state->crtc)
                return;

        if (exynos_crtc->ops->update_plane)
                exynos_crtc->ops->update_plane(exynos_crtc, exynos_plane);
}

static void exynos_plane_atomic_disable(struct drm_plane *plane,
                                        struct drm_atomic_state *state)
{
        struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state, plane);
        struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane);
        struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(old_state->crtc);

        if (!old_state->crtc)
                return;

        if (exynos_crtc->ops->disable_plane)
                exynos_crtc->ops->disable_plane(exynos_crtc, exynos_plane);
}

static const struct drm_plane_helper_funcs plane_helper_funcs = {
        .atomic_check = exynos_plane_atomic_check,
        .atomic_update = exynos_plane_atomic_update,
        .atomic_disable = exynos_plane_atomic_disable,
};

static void exynos_plane_attach_zpos_property(struct drm_plane *plane,
                                              int zpos, bool immutable)
{
        if (immutable)
                drm_plane_create_zpos_immutable_property(plane, zpos);
        else
                drm_plane_create_zpos_property(plane, zpos, 0, MAX_PLANE - 1);
}

int exynos_plane_init(struct drm_device *dev,
                      struct exynos_drm_plane *exynos_plane, unsigned int index,
                      const struct exynos_drm_plane_config *config)
{
        int err;
        unsigned int supported_modes = BIT(DRM_MODE_BLEND_PIXEL_NONE) |
                                       BIT(DRM_MODE_BLEND_PREMULTI) |
                                       BIT(DRM_MODE_BLEND_COVERAGE);
        struct drm_plane *plane = &exynos_plane->base;

        err = drm_universal_plane_init(dev, &exynos_plane->base,
                                       1 << dev->mode_config.num_crtc,
                                       &exynos_plane_funcs,
                                       config->pixel_formats,
                                       config->num_pixel_formats,
                                       NULL, config->type, NULL);
        if (err) {
                DRM_DEV_ERROR(dev->dev, "failed to initialize plane\n");
                return err;
        }

        drm_plane_helper_add(&exynos_plane->base, &plane_helper_funcs);

        exynos_plane->index = index;
        exynos_plane->config = config;

        exynos_plane_attach_zpos_property(&exynos_plane->base, config->zpos,
                           !(config->capabilities & EXYNOS_DRM_PLANE_CAP_ZPOS));

        if (config->capabilities & EXYNOS_DRM_PLANE_CAP_PIX_BLEND)
                drm_plane_create_blend_mode_property(plane, supported_modes);

        if (config->capabilities & EXYNOS_DRM_PLANE_CAP_WIN_BLEND)
                drm_plane_create_alpha_property(plane);

        return 0;
}