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_drv.h"
15 #include "exynos_drm_gem.h"
17 #include <linux/dma-buf.h>
19 struct exynos_drm_dmabuf_attachment
{
21 enum dma_data_direction dir
;
25 static int exynos_gem_attach_dma_buf(struct dma_buf
*dmabuf
,
27 struct dma_buf_attachment
*attach
)
29 struct exynos_drm_dmabuf_attachment
*exynos_attach
;
31 exynos_attach
= kzalloc(sizeof(*exynos_attach
), GFP_KERNEL
);
35 exynos_attach
->dir
= DMA_NONE
;
36 attach
->priv
= exynos_attach
;
41 static void exynos_gem_detach_dma_buf(struct dma_buf
*dmabuf
,
42 struct dma_buf_attachment
*attach
)
44 struct exynos_drm_dmabuf_attachment
*exynos_attach
= attach
->priv
;
50 sgt
= &exynos_attach
->sgt
;
52 if (exynos_attach
->dir
!= DMA_NONE
)
53 dma_unmap_sg(attach
->dev
, sgt
->sgl
, sgt
->nents
,
61 static struct sg_table
*
62 exynos_gem_map_dma_buf(struct dma_buf_attachment
*attach
,
63 enum dma_data_direction dir
)
65 struct exynos_drm_dmabuf_attachment
*exynos_attach
= attach
->priv
;
66 struct exynos_drm_gem_obj
*gem_obj
= attach
->dmabuf
->priv
;
67 struct drm_device
*dev
= gem_obj
->base
.dev
;
68 struct exynos_drm_gem_buf
*buf
;
69 struct scatterlist
*rd
, *wr
;
70 struct sg_table
*sgt
= NULL
;
74 DRM_DEBUG_PRIME("%s\n", __FILE__
);
76 /* just return current sgt if already requested. */
77 if (exynos_attach
->dir
== dir
&& exynos_attach
->is_mapped
)
78 return &exynos_attach
->sgt
;
80 buf
= gem_obj
->buffer
;
82 DRM_ERROR("buffer is null.\n");
83 return ERR_PTR(-ENOMEM
);
86 sgt
= &exynos_attach
->sgt
;
88 ret
= sg_alloc_table(sgt
, buf
->sgt
->orig_nents
, GFP_KERNEL
);
90 DRM_ERROR("failed to alloc sgt.\n");
91 return ERR_PTR(-ENOMEM
);
94 mutex_lock(&dev
->struct_mutex
);
98 for (i
= 0; i
< sgt
->orig_nents
; ++i
) {
99 sg_set_page(wr
, sg_page(rd
), rd
->length
, rd
->offset
);
104 if (dir
!= DMA_NONE
) {
105 nents
= dma_map_sg(attach
->dev
, sgt
->sgl
, sgt
->orig_nents
, dir
);
107 DRM_ERROR("failed to map sgl with iommu.\n");
114 exynos_attach
->is_mapped
= true;
115 exynos_attach
->dir
= dir
;
116 attach
->priv
= exynos_attach
;
118 DRM_DEBUG_PRIME("buffer size = 0x%lx\n", buf
->size
);
121 mutex_unlock(&dev
->struct_mutex
);
125 static void exynos_gem_unmap_dma_buf(struct dma_buf_attachment
*attach
,
126 struct sg_table
*sgt
,
127 enum dma_data_direction dir
)
132 static void exynos_dmabuf_release(struct dma_buf
*dmabuf
)
134 struct exynos_drm_gem_obj
*exynos_gem_obj
= dmabuf
->priv
;
136 DRM_DEBUG_PRIME("%s\n", __FILE__
);
139 * exynos_dmabuf_release() call means that file object's
140 * f_count is 0 and it calls drm_gem_object_handle_unreference()
141 * to drop the references that these values had been increased
142 * at drm_prime_handle_to_fd()
144 if (exynos_gem_obj
->base
.export_dma_buf
== dmabuf
) {
145 exynos_gem_obj
->base
.export_dma_buf
= NULL
;
148 * drop this gem object refcount to release allocated buffer
151 drm_gem_object_unreference_unlocked(&exynos_gem_obj
->base
);
155 static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf
*dma_buf
,
156 unsigned long page_num
)
163 static void exynos_gem_dmabuf_kunmap_atomic(struct dma_buf
*dma_buf
,
164 unsigned long page_num
,
170 static void *exynos_gem_dmabuf_kmap(struct dma_buf
*dma_buf
,
171 unsigned long page_num
)
178 static void exynos_gem_dmabuf_kunmap(struct dma_buf
*dma_buf
,
179 unsigned long page_num
, void *addr
)
184 static int exynos_gem_dmabuf_mmap(struct dma_buf
*dma_buf
,
185 struct vm_area_struct
*vma
)
190 static struct dma_buf_ops exynos_dmabuf_ops
= {
191 .attach
= exynos_gem_attach_dma_buf
,
192 .detach
= exynos_gem_detach_dma_buf
,
193 .map_dma_buf
= exynos_gem_map_dma_buf
,
194 .unmap_dma_buf
= exynos_gem_unmap_dma_buf
,
195 .kmap
= exynos_gem_dmabuf_kmap
,
196 .kmap_atomic
= exynos_gem_dmabuf_kmap_atomic
,
197 .kunmap
= exynos_gem_dmabuf_kunmap
,
198 .kunmap_atomic
= exynos_gem_dmabuf_kunmap_atomic
,
199 .mmap
= exynos_gem_dmabuf_mmap
,
200 .release
= exynos_dmabuf_release
,
203 struct dma_buf
*exynos_dmabuf_prime_export(struct drm_device
*drm_dev
,
204 struct drm_gem_object
*obj
, int flags
)
206 struct exynos_drm_gem_obj
*exynos_gem_obj
= to_exynos_gem_obj(obj
);
208 return dma_buf_export(exynos_gem_obj
, &exynos_dmabuf_ops
,
209 exynos_gem_obj
->base
.size
, flags
);
212 struct drm_gem_object
*exynos_dmabuf_prime_import(struct drm_device
*drm_dev
,
213 struct dma_buf
*dma_buf
)
215 struct dma_buf_attachment
*attach
;
216 struct sg_table
*sgt
;
217 struct scatterlist
*sgl
;
218 struct exynos_drm_gem_obj
*exynos_gem_obj
;
219 struct exynos_drm_gem_buf
*buffer
;
222 DRM_DEBUG_PRIME("%s\n", __FILE__
);
224 /* is this one of own objects? */
225 if (dma_buf
->ops
== &exynos_dmabuf_ops
) {
226 struct drm_gem_object
*obj
;
228 exynos_gem_obj
= dma_buf
->priv
;
229 obj
= &exynos_gem_obj
->base
;
231 /* is it from our device? */
232 if (obj
->dev
== drm_dev
) {
234 * Importing dmabuf exported from out own gem increases
235 * refcount on gem itself instead of f_count of dmabuf.
237 drm_gem_object_reference(obj
);
242 attach
= dma_buf_attach(dma_buf
, drm_dev
->dev
);
244 return ERR_PTR(-EINVAL
);
246 get_dma_buf(dma_buf
);
248 sgt
= dma_buf_map_attachment(attach
, DMA_BIDIRECTIONAL
);
249 if (IS_ERR_OR_NULL(sgt
)) {
254 buffer
= kzalloc(sizeof(*buffer
), GFP_KERNEL
);
256 DRM_ERROR("failed to allocate exynos_drm_gem_buf.\n");
258 goto err_unmap_attach
;
261 exynos_gem_obj
= exynos_drm_gem_init(drm_dev
, dma_buf
->size
);
262 if (!exynos_gem_obj
) {
264 goto err_free_buffer
;
269 buffer
->size
= dma_buf
->size
;
270 buffer
->dma_addr
= sg_dma_address(sgl
);
272 if (sgt
->nents
== 1) {
273 /* always physically continuous memory if sgt->nents is 1. */
274 exynos_gem_obj
->flags
|= EXYNOS_BO_CONTIG
;
277 * this case could be CONTIG or NONCONTIG type but for now
279 * TODO. we have to find a way that exporter can notify
280 * the type of its own buffer to importer.
282 exynos_gem_obj
->flags
|= EXYNOS_BO_NONCONTIG
;
285 exynos_gem_obj
->buffer
= buffer
;
287 exynos_gem_obj
->base
.import_attach
= attach
;
289 DRM_DEBUG_PRIME("dma_addr = 0x%x, size = 0x%lx\n", buffer
->dma_addr
,
292 return &exynos_gem_obj
->base
;
298 dma_buf_unmap_attachment(attach
, sgt
, DMA_BIDIRECTIONAL
);
300 dma_buf_detach(dma_buf
, attach
);
301 dma_buf_put(dma_buf
);
306 MODULE_AUTHOR("Inki Dae <inki.dae@samsung.com>");
307 MODULE_DESCRIPTION("Samsung SoC DRM DMABUF Module");
308 MODULE_LICENSE("GPL");