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