1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2015 MediaTek Inc.
6 #include <linux/dma-buf.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>
14 #include "mtk_drm_drv.h"
15 #include "mtk_drm_gem.h"
17 static const struct drm_gem_object_funcs mtk_drm_gem_object_funcs = {
18 .free = mtk_drm_gem_free_object,
19 .get_sg_table = mtk_gem_prime_get_sg_table,
20 .vmap = mtk_drm_gem_prime_vmap,
21 .vunmap = mtk_drm_gem_prime_vunmap,
22 .vm_ops = &drm_gem_cma_vm_ops,
25 static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
28 struct mtk_drm_gem_obj *mtk_gem_obj;
31 size = round_up(size, PAGE_SIZE);
33 mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
35 return ERR_PTR(-ENOMEM);
37 mtk_gem_obj->base.funcs = &mtk_drm_gem_object_funcs;
39 ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
41 DRM_ERROR("failed to initialize gem object\n");
49 struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev,
50 size_t size, bool alloc_kmap)
52 struct mtk_drm_private *priv = dev->dev_private;
53 struct mtk_drm_gem_obj *mtk_gem;
54 struct drm_gem_object *obj;
57 mtk_gem = mtk_drm_gem_init(dev, size);
59 return ERR_CAST(mtk_gem);
63 mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
66 mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
68 mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
69 &mtk_gem->dma_addr, GFP_KERNEL,
71 if (!mtk_gem->cookie) {
72 DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
78 mtk_gem->kvaddr = mtk_gem->cookie;
80 DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n",
81 mtk_gem->cookie, &mtk_gem->dma_addr,
87 drm_gem_object_release(obj);
92 void mtk_drm_gem_free_object(struct drm_gem_object *obj)
94 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
95 struct mtk_drm_private *priv = obj->dev->dev_private;
98 drm_prime_gem_destroy(obj, mtk_gem->sg);
100 dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie,
101 mtk_gem->dma_addr, mtk_gem->dma_attrs);
103 /* release file pointer to gem object. */
104 drm_gem_object_release(obj);
109 int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
110 struct drm_mode_create_dumb *args)
112 struct mtk_drm_gem_obj *mtk_gem;
115 args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
116 args->size = args->pitch * args->height;
118 mtk_gem = mtk_drm_gem_create(dev, args->size, false);
120 return PTR_ERR(mtk_gem);
123 * allocate a id of idr table where the obj is registered
124 * and handle has the id what user can see.
126 ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
128 goto err_handle_create;
130 /* drop reference from allocate - handle holds it now. */
131 drm_gem_object_put(&mtk_gem->base);
136 mtk_drm_gem_free_object(&mtk_gem->base);
140 static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj,
141 struct vm_area_struct *vma)
145 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
146 struct mtk_drm_private *priv = obj->dev->dev_private;
149 * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear
150 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
152 vma->vm_flags &= ~VM_PFNMAP;
154 ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie,
155 mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs);
157 drm_gem_vm_close(vma);
162 int mtk_drm_gem_mmap_buf(struct drm_gem_object *obj, struct vm_area_struct *vma)
166 ret = drm_gem_mmap_obj(obj, obj->size, vma);
170 return mtk_drm_gem_object_mmap(obj, vma);
173 int mtk_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
175 struct drm_gem_object *obj;
178 ret = drm_gem_mmap(filp, vma);
182 obj = vma->vm_private_data;
185 * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
186 * whole buffer from the start.
190 return mtk_drm_gem_object_mmap(obj, vma);
194 * Allocate a sg_table for this GEM object.
195 * Note: Both the table's contents, and the sg_table itself must be freed by
197 * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
199 struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
201 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
202 struct mtk_drm_private *priv = obj->dev->dev_private;
203 struct sg_table *sgt;
206 sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
208 return ERR_PTR(-ENOMEM);
210 ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie,
211 mtk_gem->dma_addr, obj->size,
214 DRM_ERROR("failed to allocate sgt, %d\n", ret);
222 struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
223 struct dma_buf_attachment *attach, struct sg_table *sg)
225 struct mtk_drm_gem_obj *mtk_gem;
227 /* check if the entries in the sg_table are contiguous */
228 if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) {
229 DRM_ERROR("sg_table is not contiguous");
230 return ERR_PTR(-EINVAL);
233 mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
235 return ERR_CAST(mtk_gem);
237 mtk_gem->dma_addr = sg_dma_address(sg->sgl);
240 return &mtk_gem->base;
243 int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
245 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
246 struct sg_table *sgt = NULL;
252 sgt = mtk_gem_prime_get_sg_table(obj);
256 npages = obj->size >> PAGE_SHIFT;
257 mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL);
258 if (!mtk_gem->pages) {
263 drm_prime_sg_to_page_array(sgt, mtk_gem->pages, npages);
265 mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP,
266 pgprot_writecombine(PAGE_KERNEL));
270 dma_buf_map_set_vaddr(map, mtk_gem->kvaddr);
275 void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
277 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
278 void *vaddr = map->vaddr;
285 kfree(mtk_gem->pages);