1 /* exynos_drm_buf.c
2 *
3 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4 * Author: Inki Dae <inki.dae@samsung.com>
5 *
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.
10 */
11
12 #include <drm/drmP.h>
13 #include <drm/exynos_drm.h>
14
15 #include "exynos_drm_drv.h"
16 #include "exynos_drm_gem.h"
17 #include "exynos_drm_buf.h"
18 #include "exynos_drm_iommu.h"
19
lowlevel_buffer_allocate(struct drm_device * dev,unsigned int flags,struct exynos_drm_gem_buf * buf)20 static int lowlevel_buffer_allocate(struct drm_device *dev,
21 unsigned int flags, struct exynos_drm_gem_buf *buf)
22 {
23 int ret = 0;
24 enum dma_attr attr;
25 unsigned int nr_pages;
26
27 if (buf->dma_addr) {
28 DRM_DEBUG_KMS("already allocated.\n");
29 return 0;
30 }
31
32 init_dma_attrs(&buf->dma_attrs);
33
34 /*
35 * if EXYNOS_BO_CONTIG, fully physically contiguous memory
36 * region will be allocated else physically contiguous
37 * as possible.
38 */
39 if (!(flags & EXYNOS_BO_NONCONTIG))
40 dma_set_attr(DMA_ATTR_FORCE_CONTIGUOUS, &buf->dma_attrs);
41
42 /*
43 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping
44 * else cachable mapping.
45 */
46 if (flags & EXYNOS_BO_WC || !(flags & EXYNOS_BO_CACHABLE))
47 attr = DMA_ATTR_WRITE_COMBINE;
48 else
49 attr = DMA_ATTR_NON_CONSISTENT;
50
51 dma_set_attr(attr, &buf->dma_attrs);
52 dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &buf->dma_attrs);
53
54 nr_pages = buf->size >> PAGE_SHIFT;
55
56 if (!is_drm_iommu_supported(dev)) {
57 dma_addr_t start_addr;
58 unsigned int i = 0;
59
60 buf->pages = drm_calloc_large(nr_pages, sizeof(struct page *));
61 if (!buf->pages) {
62 DRM_ERROR("failed to allocate pages.\n");
63 return -ENOMEM;
64 }
65
66 buf->cookie = dma_alloc_attrs(dev->dev,
67 buf->size,
68 &buf->dma_addr, GFP_KERNEL,
69 &buf->dma_attrs);
70 if (!buf->cookie) {
71 DRM_ERROR("failed to allocate buffer.\n");
72 ret = -ENOMEM;
73 goto err_free;
74 }
75
76 start_addr = buf->dma_addr;
77 while (i < nr_pages) {
78 buf->pages[i] = phys_to_page(start_addr);
79 start_addr += PAGE_SIZE;
80 i++;
81 }
82 } else {
83
84 buf->pages = dma_alloc_attrs(dev->dev, buf->size,
85 &buf->dma_addr, GFP_KERNEL,
86 &buf->dma_attrs);
87 if (!buf->pages) {
88 DRM_ERROR("failed to allocate buffer.\n");
89 return -ENOMEM;
90 }
91 }
92
93 buf->sgt = drm_prime_pages_to_sg(buf->pages, nr_pages);
94 if (IS_ERR(buf->sgt)) {
95 DRM_ERROR("failed to get sg table.\n");
96 ret = PTR_ERR(buf->sgt);
97 goto err_free_attrs;
98 }
99
100 DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
101 (unsigned long)buf->dma_addr,
102 buf->size);
103
104 return ret;
105
106 err_free_attrs:
107 dma_free_attrs(dev->dev, buf->size, buf->pages,
108 (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
109 buf->dma_addr = (dma_addr_t)NULL;
110 err_free:
111 if (!is_drm_iommu_supported(dev))
112 drm_free_large(buf->pages);
113
114 return ret;
115 }
116
lowlevel_buffer_deallocate(struct drm_device * dev,unsigned int flags,struct exynos_drm_gem_buf * buf)117 static void lowlevel_buffer_deallocate(struct drm_device *dev,
118 unsigned int flags, struct exynos_drm_gem_buf *buf)
119 {
120 if (!buf->dma_addr) {
121 DRM_DEBUG_KMS("dma_addr is invalid.\n");
122 return;
123 }
124
125 DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
126 (unsigned long)buf->dma_addr,
127 buf->size);
128
129 sg_free_table(buf->sgt);
130
131 kfree(buf->sgt);
132 buf->sgt = NULL;
133
134 if (!is_drm_iommu_supported(dev)) {
135 dma_free_attrs(dev->dev, buf->size, buf->cookie,
136 (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
137 drm_free_large(buf->pages);
138 } else
139 dma_free_attrs(dev->dev, buf->size, buf->pages,
140 (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
141
142 buf->dma_addr = (dma_addr_t)NULL;
143 }
144
exynos_drm_init_buf(struct drm_device * dev,unsigned int size)145 struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
146 unsigned int size)
147 {
148 struct exynos_drm_gem_buf *buffer;
149
150 DRM_DEBUG_KMS("desired size = 0x%x\n", size);
151
152 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
153 if (!buffer)
154 return NULL;
155
156 buffer->size = size;
157 return buffer;
158 }
159
exynos_drm_fini_buf(struct drm_device * dev,struct exynos_drm_gem_buf * buffer)160 void exynos_drm_fini_buf(struct drm_device *dev,
161 struct exynos_drm_gem_buf *buffer)
162 {
163 kfree(buffer);
164 buffer = NULL;
165 }
166
exynos_drm_alloc_buf(struct drm_device * dev,struct exynos_drm_gem_buf * buf,unsigned int flags)167 int exynos_drm_alloc_buf(struct drm_device *dev,
168 struct exynos_drm_gem_buf *buf, unsigned int flags)
169 {
170
171 /*
172 * allocate memory region and set the memory information
173 * to vaddr and dma_addr of a buffer object.
174 */
175 if (lowlevel_buffer_allocate(dev, flags, buf) < 0)
176 return -ENOMEM;
177
178 return 0;
179 }
180
exynos_drm_free_buf(struct drm_device * dev,unsigned int flags,struct exynos_drm_gem_buf * buffer)181 void exynos_drm_free_buf(struct drm_device *dev,
182 unsigned int flags, struct exynos_drm_gem_buf *buffer)
183 {
184
185 lowlevel_buffer_deallocate(dev, flags, buffer);
186 }
187