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