drivers/gpu/drm/mediatek/mtk_drm_gem.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015 MediaTek Inc.
   4  */
   5
   6 #include <linux/dma-buf.h>
   7
   8 #include <drm/drm.h>
   9 #include <drm/drm_device.h>
  10 #include <drm/drm_gem.h>
  11 #include <drm/drm_prime.h>
  12
  13 #include "mtk_drm_drv.h"
  14 #include "mtk_drm_gem.h"
  15
  16 static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
  17                                                 unsigned long size)
  18 {
  19         struct mtk_drm_gem_obj *mtk_gem_obj;
  20         int ret;
  21
  22         size = round_up(size, PAGE_SIZE);
  23
  24         mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
  25         if (!mtk_gem_obj)
  26                 return ERR_PTR(-ENOMEM);
  27
  28         ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
  29         if (ret < 0) {
  30                 DRM_ERROR("failed to initialize gem object\n");
  31                 kfree(mtk_gem_obj);
  32                 return ERR_PTR(ret);
  33         }
  34
  35         return mtk_gem_obj;
  36 }
  37
  38 struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
  39                                            size_t size, bool alloc_kmap)
  40 {
  41         struct mtk_drm_private *priv = dev->dev_private;
  42         struct mtk_drm_gem_obj *mtk_gem;
  43         struct drm_gem_object *obj;
  44         int ret;
  45
  46         mtk_gem = mtk_drm_gem_init(dev, size);
  47         if (IS_ERR(mtk_gem))
  48                 return ERR_CAST(mtk_gem);
  49
  50         obj = &mtk_gem->base;
  51
  52         mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
  53
  54         if (!alloc_kmap)
  55                 mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
  56
  57         mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
  58                                           &mtk_gem->dma_addr, GFP_KERNEL,
  59                                           mtk_gem->dma_attrs);
  60         if (!mtk_gem->cookie) {
  61                 DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
  62                 ret = -ENOMEM;
  63                 goto err_gem_free;
  64         }
  65
  66         if (alloc_kmap)
  67                 mtk_gem->kvaddr = mtk_gem->cookie;
  68
  69         DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n",
  70                          mtk_gem->cookie, &mtk_gem->dma_addr,
  71                          size);
  72
  73         return mtk_gem;
  74
  75 err_gem_free:
  76         drm_gem_object_release(obj);
  77         kfree(mtk_gem);
  78         return ERR_PTR(ret);
  79 }
  80
  81 void mtk_drm_gem_free_object(struct drm_gem_object *obj)
  82 {
  83         struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
  84         struct mtk_drm_private *priv = obj->dev->dev_private;
  85
  86         if (mtk_gem->sg)
  87                 drm_prime_gem_destroy(obj, mtk_gem->sg);
  88         else
  89                 dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie,
  90                                mtk_gem->dma_addr, mtk_gem->dma_attrs);
  91
  92         /* release file pointer to gem object. */
  93         drm_gem_object_release(obj);
  94
  95         kfree(mtk_gem);
  96 }
  97
  98 int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
  99                             struct drm_mode_create_dumb *args)
 100 {
 101         struct mtk_drm_gem_obj *mtk_gem;
 102         int ret;
 103
 104         args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
 105         args->size = args->pitch * args->height;
 106
 107         mtk_gem = mtk_drm_gem_create(dev, args->size, false);
 108         if (IS_ERR(mtk_gem))
 109                 return PTR_ERR(mtk_gem);
 110
 111         /*
 112          * allocate a id of idr table where the obj is registered
 113          * and handle has the id what user can see.
 114          */
 115         ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
 116         if (ret)
 117                 goto err_handle_create;
 118
 119         /* drop reference from allocate - handle holds it now. */
 120         drm_gem_object_put_unlocked(&mtk_gem->base);
 121
 122         return 0;
 123
 124 err_handle_create:
 125         mtk_drm_gem_free_object(&mtk_gem->base);
 126         return ret;
 127 }
 128
 129 static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj,
 130                                    struct vm_area_struct *vma)
 131
 132 {
 133         int ret;
 134         struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
 135         struct mtk_drm_private *priv = obj->dev->dev_private;
 136
 137         /*
 138          * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear
 139          * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
 140          */
 141         vma->vm_flags &= ~VM_PFNMAP;
 142
 143         ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie,
 144                              mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs);
 145         if (ret)
 146                 drm_gem_vm_close(vma);
 147
 148         return ret;
 149 }
 150
 151 int mtk_drm_gem_mmap_buf(struct drm_gem_object *obj, struct vm_area_struct *vma)
 152 {
 153         int ret;
 154
 155         ret = drm_gem_mmap_obj(obj, obj->size, vma);
 156         if (ret)
 157                 return ret;
 158
 159         return mtk_drm_gem_object_mmap(obj, vma);
 160 }
 161
 162 int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 163 {
 164         struct drm_gem_object *obj;
 165         int ret;
 166
 167         ret = drm_gem_mmap(filp, vma);
 168         if (ret)
 169                 return ret;
 170
 171         obj = vma->vm_private_data;
 172
 173         /*
 174          * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
 175          * whole buffer from the start.
 176          */
 177         vma->vm_pgoff = 0;
 178
 179         return mtk_drm_gem_object_mmap(obj, vma);
 180 }
 181
 182 /*
 183  * Allocate a sg_table for this GEM object.
 184  * Note: Both the table's contents, and the sg_table itself must be freed by
 185  *       the caller.
 186  * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
 187  */
 188 struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
 189 {
 190         struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
 191         struct mtk_drm_private *priv = obj->dev->dev_private;
 192         struct sg_table *sgt;
 193         int ret;
 194
 195         sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
 196         if (!sgt)
 197                 return ERR_PTR(-ENOMEM);
 198
 199         ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie,
 200                                     mtk_gem->dma_addr, obj->size,
 201                                     mtk_gem->dma_attrs);
 202         if (ret) {
 203                 DRM_ERROR("failed to allocate sgt, %d\n", ret);
 204                 kfree(sgt);
 205                 return ERR_PTR(ret);
 206         }
 207
 208         return sgt;
 209 }
 210
 211 struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
 212                         struct dma_buf_attachment *attach, struct sg_table *sg)
 213 {
 214         struct mtk_drm_gem_obj *mtk_gem;
 215         int ret;
 216         struct scatterlist *s;
 217         unsigned int i;
 218         dma_addr_t expected;
 219
 220         mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
 221
 222         if (IS_ERR(mtk_gem))
 223                 return ERR_CAST(mtk_gem);
 224
 225         expected = sg_dma_address(sg->sgl);
 226         for_each_sg(sg->sgl, s, sg->nents, i) {
 227                 if (sg_dma_address(s) != expected) {
 228                         DRM_ERROR("sg_table is not contiguous");
 229                         ret = -EINVAL;
 230                         goto err_gem_free;
 231                 }
 232                 expected = sg_dma_address(s) + sg_dma_len(s);
 233         }
 234
 235         mtk_gem->dma_addr = sg_dma_address(sg->sgl);
 236         mtk_gem->sg = sg;
 237
 238         return &mtk_gem->base;
 239
 240 err_gem_free:
 241         kfree(mtk_gem);
 242         return ERR_PTR(ret);
 243 }
 244
 245 void *mtk_drm_gem_prime_vmap(struct drm_gem_object *obj)
 246 {
 247         struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
 248         struct sg_table *sgt;
 249         struct sg_page_iter iter;
 250         unsigned int npages;
 251         unsigned int i = 0;
 252
 253         if (mtk_gem->kvaddr)
 254                 return mtk_gem->kvaddr;
 255
 256         sgt = mtk_gem_prime_get_sg_table(obj);
 257         if (IS_ERR(sgt))
 258                 return NULL;
 259
 260         npages = obj->size >> PAGE_SHIFT;
 261         mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL);
 262         if (!mtk_gem->pages)
 263                 goto out;
 264
 265         for_each_sg_page(sgt->sgl, &iter, sgt->orig_nents, 0) {
 266                 mtk_gem->pages[i++] = sg_page_iter_page(&iter);
 267                 if (i > npages)
 268                         break;
 269         }
 270         mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP,
 271                                pgprot_writecombine(PAGE_KERNEL));
 272
 273 out:
 274         kfree(sgt);
 275
 276         return mtk_gem->kvaddr;
 277 }
 278
 279 void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
 280 {
 281         struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
 282
 283         if (!mtk_gem->pages)
 284                 return;
 285
 286         vunmap(vaddr);
 287         mtk_gem->kvaddr = 0;
 288         kfree(mtk_gem->pages);
 289 }