text: /* exynos_drm_fb.c
   *
   * Copyright (c) 2011 Samsung Electronics Co., Ltd.
   * Authors:
   *	Inki Dae <inki.dae@samsung.com>
   *	Joonyoung Shim <jy0922.shim@samsung.com>
   *	Seung-Woo Kim <sw0312.kim@samsung.com>
   *
   * This program is free software; you can redistribute  it and/or modify it
   * under  the terms of  the GNU General  Public License as published by the
   * Free Software Foundation;  either version 2 of the  License, or (at your
   * option) any later version.
   */
  
  #include <drm/drmP.h>
  #include <drm/drm_crtc.h>
  #include <drm/drm_crtc_helper.h>
  #include <drm/drm_fb_helper.h>
  #include <drm/drm_atomic.h>
  #include <drm/drm_atomic_helper.h>
  #include <uapi/drm/exynos_drm.h>
  
  #include "exynos_drm_drv.h"
  #include "exynos_drm_fb.h"
  #include "exynos_drm_fbdev.h"
  #include "exynos_drm_iommu.h"
  #include "exynos_drm_crtc.h"
  
  #define to_exynos_fb(x)	container_of(x, struct exynos_drm_fb, fb)
  
  /*
   * exynos specific framebuffer structure.
   *
   * @fb: drm framebuffer obejct.
   * @exynos_gem: array of exynos specific gem object containing a gem object.
   */
  struct exynos_drm_fb {
  	struct drm_framebuffer	fb;
  	struct exynos_drm_gem	*exynos_gem[MAX_FB_BUFFER];
  	dma_addr_t			dma_addr[MAX_FB_BUFFER];
  };
  
  static int check_fb_gem_memory_type(struct drm_device *drm_dev,
  				    struct exynos_drm_gem *exynos_gem)
  {
  	unsigned int flags;
  
  	/*
  	 * if exynos drm driver supports iommu then framebuffer can use
  	 * all the buffer types.
  	 */
  	if (is_drm_iommu_supported(drm_dev))
  		return 0;
  
  	flags = exynos_gem->flags;
  
  	/*
  	 * Physically non-contiguous memory type for framebuffer is not
  	 * supported without IOMMU.
  	 */
  	if (IS_NONCONTIG_BUFFER(flags)) {
  		DRM_ERROR("Non-contiguous GEM memory is not supported.\n");
  		return -EINVAL;
  	}
  
  	return 0;
  }
  
  static void exynos_drm_fb_destroy(struct drm_framebuffer *fb)
  {
  	struct exynos_drm_fb *exynos_fb = to_exynos_fb(fb);
  	unsigned int i;
  
  	drm_framebuffer_cleanup(fb);
  
  	for (i = 0; i < ARRAY_SIZE(exynos_fb->exynos_gem); i++) {
  		struct drm_gem_object *obj;
  
  		if (exynos_fb->exynos_gem[i] == NULL)
  			continue;
  
  		obj = &exynos_fb->exynos_gem[i]->base;
  		drm_gem_object_unreference_unlocked(obj);
  	}
  
  	kfree(exynos_fb);
  	exynos_fb = NULL;
  }
  
  static int exynos_drm_fb_create_handle(struct drm_framebuffer *fb,
  					struct drm_file *file_priv,
  					unsigned int *handle)
  {
  	struct exynos_drm_fb *exynos_fb = to_exynos_fb(fb);
  
  	return drm_gem_handle_create(file_priv,
  				     &exynos_fb->exynos_gem[0]->base, handle);
  }
  
  static const struct drm_framebuffer_funcs exynos_drm_fb_funcs = {
  	.destroy	= exynos_drm_fb_destroy,
  	.create_handle	= exynos_drm_fb_create_handle,
  };
  
  struct drm_framebuffer *
  exynos_drm_framebuffer_init(struct drm_device *dev,
  			    const struct drm_mode_fb_cmd2 *mode_cmd,
  			    struct exynos_drm_gem **exynos_gem,
  			    int count)
  {
  	struct exynos_drm_fb *exynos_fb;
  	int i;
  	int ret;
  
  	exynos_fb = kzalloc(sizeof(*exynos_fb), GFP_KERNEL);
  	if (!exynos_fb)
  		return ERR_PTR(-ENOMEM);
  
  	for (i = 0; i < count; i++) {
  		ret = check_fb_gem_memory_type(dev, exynos_gem[i]);
  		if (ret < 0)
  			goto err;
  
  		exynos_fb->exynos_gem[i] = exynos_gem[i];
  		exynos_fb->dma_addr[i] = exynos_gem[i]->dma_addr
  						+ mode_cmd->offsets[i];
  	}
  
  	drm_helper_mode_fill_fb_struct(&exynos_fb->fb, mode_cmd);
  
  	ret = drm_framebuffer_init(dev, &exynos_fb->fb, &exynos_drm_fb_funcs);
  	if (ret < 0) {
  		DRM_ERROR("failed to initialize framebuffer\n");
  		goto err;
  	}
  
  	return &exynos_fb->fb;
  
  err:
  	kfree(exynos_fb);
  	return ERR_PTR(ret);
  }
  
  static struct drm_framebuffer *
  exynos_user_fb_create(struct drm_device *dev, struct drm_file *file_priv,
  		      const struct drm_mode_fb_cmd2 *mode_cmd)
  {
  	struct exynos_drm_gem *exynos_gem[MAX_FB_BUFFER];
  	struct drm_gem_object *obj;
  	struct drm_framebuffer *fb;
  	int i;
  	int ret;
  
  	for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
  		obj = drm_gem_object_lookup(file_priv, mode_cmd->handles[i]);
  		if (!obj) {
  			DRM_ERROR("failed to lookup gem object\n");
  			ret = -ENOENT;
  			goto err;
  		}
  
  		exynos_gem[i] = to_exynos_gem(obj);
  	}
  
  	fb = exynos_drm_framebuffer_init(dev, mode_cmd, exynos_gem, i);
  	if (IS_ERR(fb)) {
  		ret = PTR_ERR(fb);
  		goto err;
  	}
  
  	return fb;
  
  err:
  	while (i--)
  		drm_gem_object_unreference_unlocked(&exynos_gem[i]->base);
  
  	return ERR_PTR(ret);
  }
  
  dma_addr_t exynos_drm_fb_dma_addr(struct drm_framebuffer *fb, int index)
  {
  	struct exynos_drm_fb *exynos_fb = to_exynos_fb(fb);
  
  	if (index >= MAX_FB_BUFFER)
  		return DMA_ERROR_CODE;
  
  	return exynos_fb->dma_addr[index];
  }
  
  static const struct drm_mode_config_funcs exynos_drm_mode_config_funcs = {
  	.fb_create = exynos_user_fb_create,
  	.output_poll_changed = exynos_drm_output_poll_changed,
  	.atomic_check = exynos_atomic_check,
  	.atomic_commit = exynos_atomic_commit,
  };
  
  void exynos_drm_mode_config_init(struct drm_device *dev)
  {
  	dev->mode_config.min_width = 0;
  	dev->mode_config.min_height = 0;
  
  	/*
  	 * set max width and height as default value(4096x4096).
  	 * this value would be used to check framebuffer size limitation
  	 * at drm_mode_addfb().
  	 */
  	dev->mode_config.max_width = 4096;
  	dev->mode_config.max_height = 4096;
  
  	dev->mode_config.funcs = &exynos_drm_mode_config_funcs;
  }
  