drivers/gpu/drm/mediatek/mtk_drm_fb.c

   1 /*
   2  * Copyright (c) 2015 MediaTek Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <drm/drmP.h>
  15 #include <drm/drm_modeset_helper.h>
  16 #include <drm/drm_fb_helper.h>
  17 #include <drm/drm_gem.h>
  18 #include <drm/drm_gem_framebuffer_helper.h>
  19 #include <linux/dma-buf.h>
  20 #include <linux/reservation.h>
  21
  22 #include "mtk_drm_drv.h"
  23 #include "mtk_drm_fb.h"
  24 #include "mtk_drm_gem.h"
  25
  26 static const struct drm_framebuffer_funcs mtk_drm_fb_funcs = {
  27         .create_handle = drm_gem_fb_create_handle,
  28         .destroy = drm_gem_fb_destroy,
  29 };
  30
  31 static struct drm_framebuffer *mtk_drm_framebuffer_init(struct drm_device *dev,
  32                                         const struct drm_mode_fb_cmd2 *mode,
  33                                         struct drm_gem_object *obj)
  34 {
  35         struct drm_framebuffer *fb;
  36         int ret;
  37
  38         if (drm_format_num_planes(mode->pixel_format) != 1)
  39                 return ERR_PTR(-EINVAL);
  40
  41         fb = kzalloc(sizeof(*fb), GFP_KERNEL);
  42         if (!fb)
  43                 return ERR_PTR(-ENOMEM);
  44
  45         drm_helper_mode_fill_fb_struct(dev, fb, mode);
  46
  47         fb->obj[0] = obj;
  48
  49         ret = drm_framebuffer_init(dev, fb, &mtk_drm_fb_funcs);
  50         if (ret) {
  51                 DRM_ERROR("failed to initialize framebuffer\n");
  52                 kfree(fb);
  53                 return ERR_PTR(ret);
  54         }
  55
  56         return fb;
  57 }
  58
  59 /*
  60  * Wait for any exclusive fence in fb's gem object's reservation object.
  61  *
  62  * Returns -ERESTARTSYS if interrupted, else 0.
  63  */
  64 int mtk_fb_wait(struct drm_framebuffer *fb)
  65 {
  66         struct drm_gem_object *gem;
  67         struct reservation_object *resv;
  68         long ret;
  69
  70         if (!fb)
  71                 return 0;
  72
  73         gem = fb->obj[0];
  74         if (!gem || !gem->dma_buf || !gem->dma_buf->resv)
  75                 return 0;
  76
  77         resv = gem->dma_buf->resv;
  78         ret = reservation_object_wait_timeout_rcu(resv, false, true,
  79                                                   MAX_SCHEDULE_TIMEOUT);
  80         /* MAX_SCHEDULE_TIMEOUT on success, -ERESTARTSYS if interrupted */
  81         if (WARN_ON(ret < 0))
  82                 return ret;
  83
  84         return 0;
  85 }
  86
  87 struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
  88                                                struct drm_file *file,
  89                                                const struct drm_mode_fb_cmd2 *cmd)
  90 {
  91         struct drm_framebuffer *fb;
  92         struct drm_gem_object *gem;
  93         unsigned int width = cmd->width;
  94         unsigned int height = cmd->height;
  95         unsigned int size, bpp;
  96         int ret;
  97
  98         if (drm_format_num_planes(cmd->pixel_format) != 1)
  99                 return ERR_PTR(-EINVAL);
 100
 101         gem = drm_gem_object_lookup(file, cmd->handles[0]);
 102         if (!gem)
 103                 return ERR_PTR(-ENOENT);
 104
 105         bpp = drm_format_plane_cpp(cmd->pixel_format, 0);
 106         size = (height - 1) * cmd->pitches[0] + width * bpp;
 107         size += cmd->offsets[0];
 108
 109         if (gem->size < size) {
 110                 ret = -EINVAL;
 111                 goto unreference;
 112         }
 113
 114         fb = mtk_drm_framebuffer_init(dev, cmd, gem);
 115         if (IS_ERR(fb)) {
 116                 ret = PTR_ERR(fb);
 117                 goto unreference;
 118         }
 119
 120         return fb;
 121
 122 unreference:
 123         drm_gem_object_put_unlocked(gem);
 124         return ERR_PTR(ret);
 125 }