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_crtc_helper.h>
  16 #include <drm/drm_fb_helper.h>
  17 #include <drm/drm_gem.h>
  18 #include <linux/dma-buf.h>
  19 #include <linux/reservation.h>
  20
  21 #include "mtk_drm_drv.h"
  22 #include "mtk_drm_fb.h"
  23 #include "mtk_drm_gem.h"
  24
  25 /*
  26  * mtk specific framebuffer structure.
  27  *
  28  * @fb: drm framebuffer object.
  29  * @gem_obj: array of gem objects.
  30  */
  31 struct mtk_drm_fb {
  32         struct drm_framebuffer  base;
  33         /* For now we only support a single plane */
  34         struct drm_gem_object   *gem_obj;
  35 };
  36
  37 #define to_mtk_fb(x) container_of(x, struct mtk_drm_fb, base)
  38
  39 struct drm_gem_object *mtk_fb_get_gem_obj(struct drm_framebuffer *fb)
  40 {
  41         struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
  42
  43         return mtk_fb->gem_obj;
  44 }
  45
  46 static int mtk_drm_fb_create_handle(struct drm_framebuffer *fb,
  47                                     struct drm_file *file_priv,
  48                                     unsigned int *handle)
  49 {
  50         struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
  51
  52         return drm_gem_handle_create(file_priv, mtk_fb->gem_obj, handle);
  53 }
  54
  55 static void mtk_drm_fb_destroy(struct drm_framebuffer *fb)
  56 {
  57         struct mtk_drm_fb *mtk_fb = to_mtk_fb(fb);
  58
  59         drm_framebuffer_cleanup(fb);
  60
  61         drm_gem_object_unreference_unlocked(mtk_fb->gem_obj);
  62
  63         kfree(mtk_fb);
  64 }
  65
  66 static const struct drm_framebuffer_funcs mtk_drm_fb_funcs = {
  67         .create_handle = mtk_drm_fb_create_handle,
  68         .destroy = mtk_drm_fb_destroy,
  69 };
  70
  71 static struct mtk_drm_fb *mtk_drm_framebuffer_init(struct drm_device *dev,
  72                                         const struct drm_mode_fb_cmd2 *mode,
  73                                         struct drm_gem_object *obj)
  74 {
  75         struct mtk_drm_fb *mtk_fb;
  76         int ret;
  77
  78         if (drm_format_num_planes(mode->pixel_format) != 1)
  79                 return ERR_PTR(-EINVAL);
  80
  81         mtk_fb = kzalloc(sizeof(*mtk_fb), GFP_KERNEL);
  82         if (!mtk_fb)
  83                 return ERR_PTR(-ENOMEM);
  84
  85         drm_helper_mode_fill_fb_struct(dev, &mtk_fb->base, mode);
  86
  87         mtk_fb->gem_obj = obj;
  88
  89         ret = drm_framebuffer_init(dev, &mtk_fb->base, &mtk_drm_fb_funcs);
  90         if (ret) {
  91                 DRM_ERROR("failed to initialize framebuffer\n");
  92                 kfree(mtk_fb);
  93                 return ERR_PTR(ret);
  94         }
  95
  96         return mtk_fb;
  97 }
  98
  99 /*
 100  * Wait for any exclusive fence in fb's gem object's reservation object.
 101  *
 102  * Returns -ERESTARTSYS if interrupted, else 0.
 103  */
 104 int mtk_fb_wait(struct drm_framebuffer *fb)
 105 {
 106         struct drm_gem_object *gem;
 107         struct reservation_object *resv;
 108         long ret;
 109
 110         if (!fb)
 111                 return 0;
 112
 113         gem = mtk_fb_get_gem_obj(fb);
 114         if (!gem || !gem->dma_buf || !gem->dma_buf->resv)
 115                 return 0;
 116
 117         resv = gem->dma_buf->resv;
 118         ret = reservation_object_wait_timeout_rcu(resv, false, true,
 119                                                   MAX_SCHEDULE_TIMEOUT);
 120         /* MAX_SCHEDULE_TIMEOUT on success, -ERESTARTSYS if interrupted */
 121         if (WARN_ON(ret < 0))
 122                 return ret;
 123
 124         return 0;
 125 }
 126
 127 struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev,
 128                                                struct drm_file *file,
 129                                                const struct drm_mode_fb_cmd2 *cmd)
 130 {
 131         struct mtk_drm_fb *mtk_fb;
 132         struct drm_gem_object *gem;
 133         unsigned int width = cmd->width;
 134         unsigned int height = cmd->height;
 135         unsigned int size, bpp;
 136         int ret;
 137
 138         if (drm_format_num_planes(cmd->pixel_format) != 1)
 139                 return ERR_PTR(-EINVAL);
 140
 141         gem = drm_gem_object_lookup(file, cmd->handles[0]);
 142         if (!gem)
 143                 return ERR_PTR(-ENOENT);
 144
 145         bpp = drm_format_plane_cpp(cmd->pixel_format, 0);
 146         size = (height - 1) * cmd->pitches[0] + width * bpp;
 147         size += cmd->offsets[0];
 148
 149         if (gem->size < size) {
 150                 ret = -EINVAL;
 151                 goto unreference;
 152         }
 153
 154         mtk_fb = mtk_drm_framebuffer_init(dev, cmd, gem);
 155         if (IS_ERR(mtk_fb)) {
 156                 ret = PTR_ERR(mtk_fb);
 157                 goto unreference;
 158         }
 159
 160         return &mtk_fb->base;
 161
 162 unreference:
 163         drm_gem_object_unreference_unlocked(gem);
 164         return ERR_PTR(ret);
 165 }