xref: /openbmc/linux/drivers/gpu/drm/drm_dma.c (revision 8fdff1dc)
1 /**
2  * \file drm_dma.c
3  * DMA IOCTL and function support
4  *
5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
6  * \author Gareth Hughes <gareth@valinux.com>
7  */
8 
9 /*
10  * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
11  *
12  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14  * All Rights Reserved.
15  *
16  * Permission is hereby granted, free of charge, to any person obtaining a
17  * copy of this software and associated documentation files (the "Software"),
18  * to deal in the Software without restriction, including without limitation
19  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20  * and/or sell copies of the Software, and to permit persons to whom the
21  * Software is furnished to do so, subject to the following conditions:
22  *
23  * The above copyright notice and this permission notice (including the next
24  * paragraph) shall be included in all copies or substantial portions of the
25  * Software.
26  *
27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
30  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33  * OTHER DEALINGS IN THE SOFTWARE.
34  */
35 
36 #include <linux/export.h>
37 #include <drm/drmP.h>
38 
39 /**
40  * Initialize the DMA data.
41  *
42  * \param dev DRM device.
43  * \return zero on success or a negative value on failure.
44  *
45  * Allocate and initialize a drm_device_dma structure.
46  */
47 int drm_dma_setup(struct drm_device *dev)
48 {
49 	int i;
50 
51 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
52 	if (!dev->dma)
53 		return -ENOMEM;
54 
55 	for (i = 0; i <= DRM_MAX_ORDER; i++)
56 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
57 
58 	return 0;
59 }
60 
61 /**
62  * Cleanup the DMA resources.
63  *
64  * \param dev DRM device.
65  *
66  * Free all pages associated with DMA buffers, the buffers and pages lists, and
67  * finally the drm_device::dma structure itself.
68  */
69 void drm_dma_takedown(struct drm_device *dev)
70 {
71 	struct drm_device_dma *dma = dev->dma;
72 	int i, j;
73 
74 	if (!dma)
75 		return;
76 
77 	/* Clear dma buffers */
78 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
79 		if (dma->bufs[i].seg_count) {
80 			DRM_DEBUG("order %d: buf_count = %d,"
81 				  " seg_count = %d\n",
82 				  i,
83 				  dma->bufs[i].buf_count,
84 				  dma->bufs[i].seg_count);
85 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
86 				if (dma->bufs[i].seglist[j]) {
87 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
88 				}
89 			}
90 			kfree(dma->bufs[i].seglist);
91 		}
92 		if (dma->bufs[i].buf_count) {
93 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
94 				kfree(dma->bufs[i].buflist[j].dev_private);
95 			}
96 			kfree(dma->bufs[i].buflist);
97 		}
98 	}
99 
100 	kfree(dma->buflist);
101 	kfree(dma->pagelist);
102 	kfree(dev->dma);
103 	dev->dma = NULL;
104 }
105 
106 /**
107  * Free a buffer.
108  *
109  * \param dev DRM device.
110  * \param buf buffer to free.
111  *
112  * Resets the fields of \p buf.
113  */
114 void drm_free_buffer(struct drm_device *dev, struct drm_buf * buf)
115 {
116 	if (!buf)
117 		return;
118 
119 	buf->waiting = 0;
120 	buf->pending = 0;
121 	buf->file_priv = NULL;
122 	buf->used = 0;
123 }
124 
125 /**
126  * Reclaim the buffers.
127  *
128  * \param file_priv DRM file private.
129  *
130  * Frees each buffer associated with \p file_priv not already on the hardware.
131  */
132 void drm_core_reclaim_buffers(struct drm_device *dev,
133 			      struct drm_file *file_priv)
134 {
135 	struct drm_device_dma *dma = dev->dma;
136 	int i;
137 
138 	if (!dma)
139 		return;
140 	for (i = 0; i < dma->buf_count; i++) {
141 		if (dma->buflist[i]->file_priv == file_priv) {
142 			switch (dma->buflist[i]->list) {
143 			case DRM_LIST_NONE:
144 				drm_free_buffer(dev, dma->buflist[i]);
145 				break;
146 			case DRM_LIST_WAIT:
147 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
148 				break;
149 			default:
150 				/* Buffer already on hardware. */
151 				break;
152 			}
153 		}
154 	}
155 }
156 
157 EXPORT_SYMBOL(drm_core_reclaim_buffers);
158