3 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
4 * Author: Inki Dae <inki.dae@samsung.com>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
13 #include <drm/exynos_drm.h>
14 #include "exynos_drm_dmabuf.h"
15 #include "exynos_drm_drv.h"
16 #include "exynos_drm_gem.h"
18 #include <linux/dma-buf.h>
20 struct exynos_drm_dmabuf_attachment {
22 enum dma_data_direction dir;
26 static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
28 return to_exynos_gem_obj(buf->priv);
31 static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
33 struct dma_buf_attachment *attach)
35 struct exynos_drm_dmabuf_attachment *exynos_attach;
37 exynos_attach = kzalloc(sizeof(*exynos_attach), GFP_KERNEL);
41 exynos_attach->dir = DMA_NONE;
42 attach->priv = exynos_attach;
47 static void exynos_gem_detach_dma_buf(struct dma_buf *dmabuf,
48 struct dma_buf_attachment *attach)
50 struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
56 sgt = &exynos_attach->sgt;
58 if (exynos_attach->dir != DMA_NONE)
59 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
67 static struct sg_table *
68 exynos_gem_map_dma_buf(struct dma_buf_attachment *attach,
69 enum dma_data_direction dir)
71 struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
72 struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
73 struct drm_device *dev = gem_obj->base.dev;
74 struct exynos_drm_gem_buf *buf;
75 struct scatterlist *rd, *wr;
76 struct sg_table *sgt = NULL;
80 /* just return current sgt if already requested. */
81 if (exynos_attach->dir == dir && exynos_attach->is_mapped)
82 return &exynos_attach->sgt;
84 buf = gem_obj->buffer;
86 DRM_ERROR("buffer is null.\n");
87 return ERR_PTR(-ENOMEM);
90 sgt = &exynos_attach->sgt;
92 ret = sg_alloc_table(sgt, buf->sgt->orig_nents, GFP_KERNEL);
94 DRM_ERROR("failed to alloc sgt.\n");
95 return ERR_PTR(-ENOMEM);
98 mutex_lock(&dev->struct_mutex);
102 for (i = 0; i < sgt->orig_nents; ++i) {
103 sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
108 if (dir != DMA_NONE) {
109 nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
111 DRM_ERROR("failed to map sgl with iommu.\n");
118 exynos_attach->is_mapped = true;
119 exynos_attach->dir = dir;
120 attach->priv = exynos_attach;
122 DRM_DEBUG_PRIME("buffer size = 0x%lx\n", buf->size);
125 mutex_unlock(&dev->struct_mutex);
129 static void exynos_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
130 struct sg_table *sgt,
131 enum dma_data_direction dir)
136 static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf,
137 unsigned long page_num)
144 static void exynos_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf,
145 unsigned long page_num,
151 static void *exynos_gem_dmabuf_kmap(struct dma_buf *dma_buf,
152 unsigned long page_num)
159 static void exynos_gem_dmabuf_kunmap(struct dma_buf *dma_buf,
160 unsigned long page_num, void *addr)
165 static int exynos_gem_dmabuf_mmap(struct dma_buf *dma_buf,
166 struct vm_area_struct *vma)
171 static struct dma_buf_ops exynos_dmabuf_ops = {
172 .attach = exynos_gem_attach_dma_buf,
173 .detach = exynos_gem_detach_dma_buf,
174 .map_dma_buf = exynos_gem_map_dma_buf,
175 .unmap_dma_buf = exynos_gem_unmap_dma_buf,
176 .kmap = exynos_gem_dmabuf_kmap,
177 .kmap_atomic = exynos_gem_dmabuf_kmap_atomic,
178 .kunmap = exynos_gem_dmabuf_kunmap,
179 .kunmap_atomic = exynos_gem_dmabuf_kunmap_atomic,
180 .mmap = exynos_gem_dmabuf_mmap,
181 .release = drm_gem_dmabuf_release,
184 struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
185 struct drm_gem_object *obj, int flags)
187 struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
189 return dma_buf_export(obj, &exynos_dmabuf_ops,
190 exynos_gem_obj->base.size, flags, NULL);
193 struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
194 struct dma_buf *dma_buf)
196 struct dma_buf_attachment *attach;
197 struct sg_table *sgt;
198 struct scatterlist *sgl;
199 struct exynos_drm_gem_obj *exynos_gem_obj;
200 struct exynos_drm_gem_buf *buffer;
203 /* is this one of own objects? */
204 if (dma_buf->ops == &exynos_dmabuf_ops) {
205 struct drm_gem_object *obj;
209 /* is it from our device? */
210 if (obj->dev == drm_dev) {
212 * Importing dmabuf exported from out own gem increases
213 * refcount on gem itself instead of f_count of dmabuf.
215 drm_gem_object_reference(obj);
220 attach = dma_buf_attach(dma_buf, drm_dev->dev);
222 return ERR_PTR(-EINVAL);
224 get_dma_buf(dma_buf);
226 sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
232 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
235 goto err_unmap_attach;
238 exynos_gem_obj = exynos_drm_gem_init(drm_dev, dma_buf->size);
239 if (!exynos_gem_obj) {
241 goto err_free_buffer;
246 buffer->size = dma_buf->size;
247 buffer->dma_addr = sg_dma_address(sgl);
249 if (sgt->nents == 1) {
250 /* always physically continuous memory if sgt->nents is 1. */
251 exynos_gem_obj->flags |= EXYNOS_BO_CONTIG;
254 * this case could be CONTIG or NONCONTIG type but for now
256 * TODO. we have to find a way that exporter can notify
257 * the type of its own buffer to importer.
259 exynos_gem_obj->flags |= EXYNOS_BO_NONCONTIG;
262 exynos_gem_obj->buffer = buffer;
264 exynos_gem_obj->base.import_attach = attach;
266 DRM_DEBUG_PRIME("dma_addr = %pad, size = 0x%lx\n", &buffer->dma_addr,
269 return &exynos_gem_obj->base;
275 dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
277 dma_buf_detach(dma_buf, attach);
278 dma_buf_put(dma_buf);