Linux-libre 3.4.8-gnu1
[librecmc/linux-libre.git] / drivers / gpu / drm / exynos / exynos_drm_buf.c
1 /* exynos_drm_buf.c
2  *
3  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4  * Author: Inki Dae <inki.dae@samsung.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  */
25
26 #include "drmP.h"
27 #include "drm.h"
28 #include "exynos_drm.h"
29
30 #include "exynos_drm_drv.h"
31 #include "exynos_drm_gem.h"
32 #include "exynos_drm_buf.h"
33
34 static int lowlevel_buffer_allocate(struct drm_device *dev,
35                 unsigned int flags, struct exynos_drm_gem_buf *buf)
36 {
37         dma_addr_t start_addr;
38         unsigned int npages, page_size, i = 0;
39         struct scatterlist *sgl;
40         int ret = 0;
41
42         DRM_DEBUG_KMS("%s\n", __FILE__);
43
44         if (IS_NONCONTIG_BUFFER(flags)) {
45                 DRM_DEBUG_KMS("not support allocation type.\n");
46                 return -EINVAL;
47         }
48
49         if (buf->dma_addr) {
50                 DRM_DEBUG_KMS("already allocated.\n");
51                 return 0;
52         }
53
54         if (buf->size >= SZ_1M) {
55                 npages = buf->size >> SECTION_SHIFT;
56                 page_size = SECTION_SIZE;
57         } else if (buf->size >= SZ_64K) {
58                 npages = buf->size >> 16;
59                 page_size = SZ_64K;
60         } else {
61                 npages = buf->size >> PAGE_SHIFT;
62                 page_size = PAGE_SIZE;
63         }
64
65         buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
66         if (!buf->sgt) {
67                 DRM_ERROR("failed to allocate sg table.\n");
68                 return -ENOMEM;
69         }
70
71         ret = sg_alloc_table(buf->sgt, npages, GFP_KERNEL);
72         if (ret < 0) {
73                 DRM_ERROR("failed to initialize sg table.\n");
74                 kfree(buf->sgt);
75                 buf->sgt = NULL;
76                 return -ENOMEM;
77         }
78
79         buf->kvaddr = dma_alloc_writecombine(dev->dev, buf->size,
80                         &buf->dma_addr, GFP_KERNEL);
81         if (!buf->kvaddr) {
82                 DRM_ERROR("failed to allocate buffer.\n");
83                 ret = -ENOMEM;
84                 goto err1;
85         }
86
87         buf->pages = kzalloc(sizeof(struct page) * npages, GFP_KERNEL);
88         if (!buf->pages) {
89                 DRM_ERROR("failed to allocate pages.\n");
90                 ret = -ENOMEM;
91                 goto err2;
92         }
93
94         sgl = buf->sgt->sgl;
95         start_addr = buf->dma_addr;
96
97         while (i < npages) {
98                 buf->pages[i] = phys_to_page(start_addr);
99                 sg_set_page(sgl, buf->pages[i], page_size, 0);
100                 sg_dma_address(sgl) = start_addr;
101                 start_addr += page_size;
102                 sgl = sg_next(sgl);
103                 i++;
104         }
105
106         DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
107                         (unsigned long)buf->kvaddr,
108                         (unsigned long)buf->dma_addr,
109                         buf->size);
110
111         return ret;
112 err2:
113         dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
114                         (dma_addr_t)buf->dma_addr);
115         buf->dma_addr = (dma_addr_t)NULL;
116 err1:
117         sg_free_table(buf->sgt);
118         kfree(buf->sgt);
119         buf->sgt = NULL;
120
121         return ret;
122 }
123
124 static void lowlevel_buffer_deallocate(struct drm_device *dev,
125                 unsigned int flags, struct exynos_drm_gem_buf *buf)
126 {
127         DRM_DEBUG_KMS("%s.\n", __FILE__);
128
129         /*
130          * release only physically continuous memory and
131          * non-continuous memory would be released by exynos
132          * gem framework.
133          */
134         if (IS_NONCONTIG_BUFFER(flags)) {
135                 DRM_DEBUG_KMS("not support allocation type.\n");
136                 return;
137         }
138
139         if (!buf->dma_addr) {
140                 DRM_DEBUG_KMS("dma_addr is invalid.\n");
141                 return;
142         }
143
144         DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
145                         (unsigned long)buf->kvaddr,
146                         (unsigned long)buf->dma_addr,
147                         buf->size);
148
149         sg_free_table(buf->sgt);
150
151         kfree(buf->sgt);
152         buf->sgt = NULL;
153
154         kfree(buf->pages);
155         buf->pages = NULL;
156
157         dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
158                                 (dma_addr_t)buf->dma_addr);
159         buf->dma_addr = (dma_addr_t)NULL;
160 }
161
162 struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
163                                                 unsigned int size)
164 {
165         struct exynos_drm_gem_buf *buffer;
166
167         DRM_DEBUG_KMS("%s.\n", __FILE__);
168         DRM_DEBUG_KMS("desired size = 0x%x\n", size);
169
170         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
171         if (!buffer) {
172                 DRM_ERROR("failed to allocate exynos_drm_gem_buf.\n");
173                 return NULL;
174         }
175
176         buffer->size = size;
177         return buffer;
178 }
179
180 void exynos_drm_fini_buf(struct drm_device *dev,
181                                 struct exynos_drm_gem_buf *buffer)
182 {
183         DRM_DEBUG_KMS("%s.\n", __FILE__);
184
185         if (!buffer) {
186                 DRM_DEBUG_KMS("buffer is null.\n");
187                 return;
188         }
189
190         kfree(buffer);
191         buffer = NULL;
192 }
193
194 int exynos_drm_alloc_buf(struct drm_device *dev,
195                 struct exynos_drm_gem_buf *buf, unsigned int flags)
196 {
197
198         /*
199          * allocate memory region and set the memory information
200          * to vaddr and dma_addr of a buffer object.
201          */
202         if (lowlevel_buffer_allocate(dev, flags, buf) < 0)
203                 return -ENOMEM;
204
205         return 0;
206 }
207
208 void exynos_drm_free_buf(struct drm_device *dev,
209                 unsigned int flags, struct exynos_drm_gem_buf *buffer)
210 {
211
212         lowlevel_buffer_deallocate(dev, flags, buffer);
213 }