text: // SPDX-License-Identifier: GPL-2.0-only
  /*
   * Copyright (c) 2015 MediaTek Inc.
   * Author: CK Hu <ck.hu@mediatek.com>
   */
  
  #include <drm/drm_atomic.h>
  #include <drm/drm_atomic_helper.h>
  #include <drm/drm_fourcc.h>
  #include <drm/drm_plane_helper.h>
  #include <drm/drm_gem_framebuffer_helper.h>
  
  #include "mtk_drm_crtc.h"
  #include "mtk_drm_ddp_comp.h"
  #include "mtk_drm_drv.h"
  #include "mtk_drm_fb.h"
  #include "mtk_drm_gem.h"
  #include "mtk_drm_plane.h"
  
  static const u32 formats[] = {
  	DRM_FORMAT_XRGB8888,
  	DRM_FORMAT_ARGB8888,
  	DRM_FORMAT_RGB565,
  	DRM_FORMAT_UYVY,
  	DRM_FORMAT_YUYV,
  };
  
  static void mtk_plane_reset(struct drm_plane *plane)
  {
  	struct mtk_plane_state *state;
  
  	if (plane->state) {
  		__drm_atomic_helper_plane_destroy_state(plane->state);
  
  		state = to_mtk_plane_state(plane->state);
  		memset(state, 0, sizeof(*state));
  	} else {
  		state = kzalloc(sizeof(*state), GFP_KERNEL);
  		if (!state)
  			return;
  		plane->state = &state->base;
  	}
  
  	state->base.plane = plane;
  	state->pending.format = DRM_FORMAT_RGB565;
  }
  
  static struct drm_plane_state *mtk_plane_duplicate_state(struct drm_plane *plane)
  {
  	struct mtk_plane_state *old_state = to_mtk_plane_state(plane->state);
  	struct mtk_plane_state *state;
  
  	state = kzalloc(sizeof(*state), GFP_KERNEL);
  	if (!state)
  		return NULL;
  
  	__drm_atomic_helper_plane_duplicate_state(plane, &state->base);
  
  	WARN_ON(state->base.plane != plane);
  
  	state->pending = old_state->pending;
  
  	return &state->base;
  }
  
  static void mtk_drm_plane_destroy_state(struct drm_plane *plane,
  					struct drm_plane_state *state)
  {
  	__drm_atomic_helper_plane_destroy_state(state);
  	kfree(to_mtk_plane_state(state));
  }
  
  static const struct drm_plane_funcs mtk_plane_funcs = {
  	.update_plane = drm_atomic_helper_update_plane,
  	.disable_plane = drm_atomic_helper_disable_plane,
  	.destroy = drm_plane_cleanup,
  	.reset = mtk_plane_reset,
  	.atomic_duplicate_state = mtk_plane_duplicate_state,
  	.atomic_destroy_state = mtk_drm_plane_destroy_state,
  };
  
  static int mtk_plane_atomic_check(struct drm_plane *plane,
  				  struct drm_plane_state *state)
  {
  	struct drm_framebuffer *fb = state->fb;
  	struct drm_crtc_state *crtc_state;
  
  	if (!fb)
  		return 0;
  
  	if (!state->crtc)
  		return 0;
  
  	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
  	if (IS_ERR(crtc_state))
  		return PTR_ERR(crtc_state);
  
  	return drm_atomic_helper_check_plane_state(state, crtc_state,
  						   DRM_PLANE_HELPER_NO_SCALING,
  						   DRM_PLANE_HELPER_NO_SCALING,
  						   true, true);
  }
  
  static void mtk_plane_atomic_disable(struct drm_plane *plane,
  				     struct drm_plane_state *old_state)
  {
  	struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
  
  	state->pending.enable = false;
  	wmb(); /* Make sure the above parameter is set before update */
  	state->pending.dirty = true;
  }
  
  static void mtk_plane_atomic_update(struct drm_plane *plane,
  				    struct drm_plane_state *old_state)
  {
  	struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
  	struct drm_crtc *crtc = plane->state->crtc;
  	struct drm_framebuffer *fb = plane->state->fb;
  	struct drm_gem_object *gem;
  	struct mtk_drm_gem_obj *mtk_gem;
  	unsigned int pitch, format;
  	dma_addr_t addr;
  
  	if (!crtc || WARN_ON(!fb))
  		return;
  
  	if (!plane->state->visible) {
  		mtk_plane_atomic_disable(plane, old_state);
  		return;
  	}
  
  	gem = fb->obj[0];
  	mtk_gem = to_mtk_gem_obj(gem);
  	addr = mtk_gem->dma_addr;
  	pitch = fb->pitches[0];
  	format = fb->format->format;
  
  	addr += (plane->state->src.x1 >> 16) * fb->format->cpp[0];
  	addr += (plane->state->src.y1 >> 16) * pitch;
  
  	state->pending.enable = true;
  	state->pending.pitch = pitch;
  	state->pending.format = format;
  	state->pending.addr = addr;
  	state->pending.x = plane->state->dst.x1;
  	state->pending.y = plane->state->dst.y1;
  	state->pending.width = drm_rect_width(&plane->state->dst);
  	state->pending.height = drm_rect_height(&plane->state->dst);
  	wmb(); /* Make sure the above parameters are set before update */
  	state->pending.dirty = true;
  }
  
  static const struct drm_plane_helper_funcs mtk_plane_helper_funcs = {
  	.prepare_fb = drm_gem_fb_prepare_fb,
  	.atomic_check = mtk_plane_atomic_check,
  	.atomic_update = mtk_plane_atomic_update,
  	.atomic_disable = mtk_plane_atomic_disable,
  };
  
  int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane,
  		   unsigned long possible_crtcs, enum drm_plane_type type)
  {
  	int err;
  
  	err = drm_universal_plane_init(dev, plane, possible_crtcs,
  				       &mtk_plane_funcs, formats,
  				       ARRAY_SIZE(formats), NULL, type, NULL);
  	if (err) {
  		DRM_ERROR("failed to initialize plane\n");
  		return err;
  	}
  
  	drm_plane_helper_add(plane, &mtk_plane_helper_funcs);
  
  	return 0;
  }
  