2 * drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
4 * Copyright (C) 2011 Texas Instruments
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
16 * You should have received a copy of the GNU General Public License along with
17 * this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/dma-buf.h>
24 /* -----------------------------------------------------------------------------
28 static struct sg_table *omap_gem_map_dma_buf(
29 struct dma_buf_attachment *attachment,
30 enum dma_data_direction dir)
32 struct drm_gem_object *obj = attachment->dmabuf->priv;
37 sg = kzalloc(sizeof(*sg), GFP_KERNEL);
39 return ERR_PTR(-ENOMEM);
41 /* camera, etc, need physically contiguous.. but we need a
42 * better way to know this..
44 ret = omap_gem_get_paddr(obj, &paddr, true);
48 ret = sg_alloc_table(sg, 1, GFP_KERNEL);
52 sg_init_table(sg->sgl, 1);
53 sg_dma_len(sg->sgl) = obj->size;
54 sg_set_page(sg->sgl, pfn_to_page(PFN_DOWN(paddr)), obj->size, 0);
55 sg_dma_address(sg->sgl) = paddr;
57 /* this should be after _get_paddr() to ensure we have pages attached */
58 omap_gem_dma_sync(obj, dir);
66 static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
67 struct sg_table *sg, enum dma_data_direction dir)
69 struct drm_gem_object *obj = attachment->dmabuf->priv;
70 omap_gem_put_paddr(obj);
75 static void omap_gem_dmabuf_release(struct dma_buf *buffer)
77 struct drm_gem_object *obj = buffer->priv;
78 /* release reference that was taken when dmabuf was exported
79 * in omap_gem_prime_set()..
81 drm_gem_object_unreference_unlocked(obj);
85 static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,
86 enum dma_data_direction dir)
88 struct drm_gem_object *obj = buffer->priv;
90 if (omap_gem_flags(obj) & OMAP_BO_TILED) {
91 /* TODO we would need to pin at least part of the buffer to
92 * get de-tiled view. For now just reject it.
96 /* make sure we have the pages: */
97 return omap_gem_get_pages(obj, &pages, true);
100 static int omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,
101 enum dma_data_direction dir)
103 struct drm_gem_object *obj = buffer->priv;
104 omap_gem_put_pages(obj);
109 static void *omap_gem_dmabuf_kmap_atomic(struct dma_buf *buffer,
110 unsigned long page_num)
112 struct drm_gem_object *obj = buffer->priv;
114 omap_gem_get_pages(obj, &pages, false);
115 omap_gem_cpu_sync(obj, page_num);
116 return kmap_atomic(pages[page_num]);
119 static void omap_gem_dmabuf_kunmap_atomic(struct dma_buf *buffer,
120 unsigned long page_num, void *addr)
125 static void *omap_gem_dmabuf_kmap(struct dma_buf *buffer,
126 unsigned long page_num)
128 struct drm_gem_object *obj = buffer->priv;
130 omap_gem_get_pages(obj, &pages, false);
131 omap_gem_cpu_sync(obj, page_num);
132 return kmap(pages[page_num]);
135 static void omap_gem_dmabuf_kunmap(struct dma_buf *buffer,
136 unsigned long page_num, void *addr)
138 struct drm_gem_object *obj = buffer->priv;
140 omap_gem_get_pages(obj, &pages, false);
141 kunmap(pages[page_num]);
144 static int omap_gem_dmabuf_mmap(struct dma_buf *buffer,
145 struct vm_area_struct *vma)
147 struct drm_gem_object *obj = buffer->priv;
150 if (WARN_ON(!obj->filp))
153 ret = drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma);
157 return omap_gem_mmap_obj(obj, vma);
160 static struct dma_buf_ops omap_dmabuf_ops = {
161 .map_dma_buf = omap_gem_map_dma_buf,
162 .unmap_dma_buf = omap_gem_unmap_dma_buf,
163 .release = omap_gem_dmabuf_release,
164 .begin_cpu_access = omap_gem_dmabuf_begin_cpu_access,
165 .end_cpu_access = omap_gem_dmabuf_end_cpu_access,
166 .kmap_atomic = omap_gem_dmabuf_kmap_atomic,
167 .kunmap_atomic = omap_gem_dmabuf_kunmap_atomic,
168 .kmap = omap_gem_dmabuf_kmap,
169 .kunmap = omap_gem_dmabuf_kunmap,
170 .mmap = omap_gem_dmabuf_mmap,
173 struct dma_buf *omap_gem_prime_export(struct drm_device *dev,
174 struct drm_gem_object *obj, int flags)
176 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
178 exp_info.ops = &omap_dmabuf_ops;
179 exp_info.size = obj->size;
180 exp_info.flags = flags;
183 return dma_buf_export(&exp_info);
186 /* -----------------------------------------------------------------------------
190 struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,
191 struct dma_buf *dma_buf)
193 struct dma_buf_attachment *attach;
194 struct drm_gem_object *obj;
195 struct sg_table *sgt;
198 if (dma_buf->ops == &omap_dmabuf_ops) {
200 if (obj->dev == dev) {
202 * Importing dmabuf exported from out own gem increases
203 * refcount on gem itself instead of f_count of dmabuf.
205 drm_gem_object_reference(obj);
210 attach = dma_buf_attach(dma_buf, dev->dev);
212 return ERR_CAST(attach);
214 get_dma_buf(dma_buf);
216 sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
222 obj = omap_gem_new_dmabuf(dev, dma_buf->size, sgt);
228 obj->import_attach = attach;
233 dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
235 dma_buf_detach(dma_buf, attach);
236 dma_buf_put(dma_buf);