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(&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_len(s)) 228 break; 229 230 if (sg_dma_address(s) != expected) { 231 DRM_ERROR("sg_table is not contiguous"); 232 ret = -EINVAL; 233 goto err_gem_free; 234 } 235 expected = sg_dma_address(s) + sg_dma_len(s); 236 } 237 238 mtk_gem->dma_addr = sg_dma_address(sg->sgl); 239 mtk_gem->sg = sg; 240 241 return &mtk_gem->base; 242 243 err_gem_free: 244 kfree(mtk_gem); 245 return ERR_PTR(ret); 246 } 247 248 void *mtk_drm_gem_prime_vmap(struct drm_gem_object *obj) 249 { 250 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 251 struct sg_table *sgt; 252 struct sg_page_iter iter; 253 unsigned int npages; 254 unsigned int i = 0; 255 256 if (mtk_gem->kvaddr) 257 return mtk_gem->kvaddr; 258 259 sgt = mtk_gem_prime_get_sg_table(obj); 260 if (IS_ERR(sgt)) 261 return NULL; 262 263 npages = obj->size >> PAGE_SHIFT; 264 mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL); 265 if (!mtk_gem->pages) 266 goto out; 267 268 for_each_sg_page(sgt->sgl, &iter, sgt->orig_nents, 0) { 269 mtk_gem->pages[i++] = sg_page_iter_page(&iter); 270 if (i > npages) 271 break; 272 } 273 mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP, 274 pgprot_writecombine(PAGE_KERNEL)); 275 276 out: 277 kfree(sgt); 278 279 return mtk_gem->kvaddr; 280 } 281 282 void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr) 283 { 284 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 285 286 if (!mtk_gem->pages) 287 return; 288 289 vunmap(vaddr); 290 mtk_gem->kvaddr = 0; 291 kfree(mtk_gem->pages); 292 } 293