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 
29 #include "exynos_drm_drv.h"
30 #include "exynos_drm_gem.h"
31 #include "exynos_drm_buf.h"
32 
lowlevel_buffer_allocate(struct drm_device * dev,struct exynos_drm_gem_buf * buffer)33 static int lowlevel_buffer_allocate(struct drm_device *dev,
34 		struct exynos_drm_gem_buf *buffer)
35 {
36 	DRM_DEBUG_KMS("%s\n", __FILE__);
37 
38 	buffer->kvaddr = dma_alloc_writecombine(dev->dev, buffer->size,
39 			&buffer->dma_addr, GFP_KERNEL);
40 	if (!buffer->kvaddr) {
41 		DRM_ERROR("failed to allocate buffer.\n");
42 		return -ENOMEM;
43 	}
44 
45 	DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
46 			(unsigned long)buffer->kvaddr,
47 			(unsigned long)buffer->dma_addr,
48 			buffer->size);
49 
50 	return 0;
51 }
52 
lowlevel_buffer_deallocate(struct drm_device * dev,struct exynos_drm_gem_buf * buffer)53 static void lowlevel_buffer_deallocate(struct drm_device *dev,
54 		struct exynos_drm_gem_buf *buffer)
55 {
56 	DRM_DEBUG_KMS("%s.\n", __FILE__);
57 
58 	if (buffer->dma_addr && buffer->size)
59 		dma_free_writecombine(dev->dev, buffer->size, buffer->kvaddr,
60 				(dma_addr_t)buffer->dma_addr);
61 	else
62 		DRM_DEBUG_KMS("buffer data are invalid.\n");
63 }
64 
exynos_drm_buf_create(struct drm_device * dev,unsigned int size)65 struct exynos_drm_gem_buf *exynos_drm_buf_create(struct drm_device *dev,
66 		unsigned int size)
67 {
68 	struct exynos_drm_gem_buf *buffer;
69 
70 	DRM_DEBUG_KMS("%s.\n", __FILE__);
71 	DRM_DEBUG_KMS("desired size = 0x%x\n", size);
72 
73 	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
74 	if (!buffer) {
75 		DRM_ERROR("failed to allocate exynos_drm_gem_buf.\n");
76 		return NULL;
77 	}
78 
79 	buffer->size = size;
80 
81 	/*
82 	 * allocate memory region with size and set the memory information
83 	 * to vaddr and dma_addr of a buffer object.
84 	 */
85 	if (lowlevel_buffer_allocate(dev, buffer) < 0) {
86 		kfree(buffer);
87 		return NULL;
88 	}
89 
90 	return buffer;
91 }
92 
exynos_drm_buf_destroy(struct drm_device * dev,struct exynos_drm_gem_buf * buffer)93 void exynos_drm_buf_destroy(struct drm_device *dev,
94 		struct exynos_drm_gem_buf *buffer)
95 {
96 	DRM_DEBUG_KMS("%s.\n", __FILE__);
97 
98 	if (!buffer) {
99 		DRM_DEBUG_KMS("buffer is null.\n");
100 		return;
101 	}
102 
103 	lowlevel_buffer_deallocate(dev, buffer);
104 
105 	kfree(buffer);
106 	buffer = NULL;
107 }
108 
109 MODULE_AUTHOR("Inki Dae <inki.dae@samsung.com>");
110 MODULE_DESCRIPTION("Samsung SoC DRM Buffer Management Module");
111 MODULE_LICENSE("GPL");
112