xref: /openbmc/linux/drivers/gpu/drm/drm_dma.c (revision 4800cd83)
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 "drmP.h"
37 
38 /**
39  * Initialize the DMA data.
40  *
41  * \param dev DRM device.
42  * \return zero on success or a negative value on failure.
43  *
44  * Allocate and initialize a drm_device_dma structure.
45  */
46 int drm_dma_setup(struct drm_device *dev)
47 {
48 	int i;
49 
50 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
51 	if (!dev->dma)
52 		return -ENOMEM;
53 
54 	for (i = 0; i <= DRM_MAX_ORDER; i++)
55 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
56 
57 	return 0;
58 }
59 
60 /**
61  * Cleanup the DMA resources.
62  *
63  * \param dev DRM device.
64  *
65  * Free all pages associated with DMA buffers, the buffers and pages lists, and
66  * finally the drm_device::dma structure itself.
67  */
68 void drm_dma_takedown(struct drm_device *dev)
69 {
70 	struct drm_device_dma *dma = dev->dma;
71 	int i, j;
72 
73 	if (!dma)
74 		return;
75 
76 	/* Clear dma buffers */
77 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
78 		if (dma->bufs[i].seg_count) {
79 			DRM_DEBUG("order %d: buf_count = %d,"
80 				  " seg_count = %d\n",
81 				  i,
82 				  dma->bufs[i].buf_count,
83 				  dma->bufs[i].seg_count);
84 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
85 				if (dma->bufs[i].seglist[j]) {
86 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
87 				}
88 			}
89 			kfree(dma->bufs[i].seglist);
90 		}
91 		if (dma->bufs[i].buf_count) {
92 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
93 				kfree(dma->bufs[i].buflist[j].dev_private);
94 			}
95 			kfree(dma->bufs[i].buflist);
96 		}
97 	}
98 
99 	kfree(dma->buflist);
100 	kfree(dma->pagelist);
101 	kfree(dev->dma);
102 	dev->dma = NULL;
103 }
104 
105 /**
106  * Free a buffer.
107  *
108  * \param dev DRM device.
109  * \param buf buffer to free.
110  *
111  * Resets the fields of \p buf.
112  */
113 void drm_free_buffer(struct drm_device *dev, struct drm_buf * buf)
114 {
115 	if (!buf)
116 		return;
117 
118 	buf->waiting = 0;
119 	buf->pending = 0;
120 	buf->file_priv = NULL;
121 	buf->used = 0;
122 
123 	if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE)
124 	    && waitqueue_active(&buf->dma_wait)) {
125 		wake_up_interruptible(&buf->dma_wait);
126 	}
127 }
128 
129 /**
130  * Reclaim the buffers.
131  *
132  * \param file_priv DRM file private.
133  *
134  * Frees each buffer associated with \p file_priv not already on the hardware.
135  */
136 void drm_core_reclaim_buffers(struct drm_device *dev,
137 			      struct drm_file *file_priv)
138 {
139 	struct drm_device_dma *dma = dev->dma;
140 	int i;
141 
142 	if (!dma)
143 		return;
144 	for (i = 0; i < dma->buf_count; i++) {
145 		if (dma->buflist[i]->file_priv == file_priv) {
146 			switch (dma->buflist[i]->list) {
147 			case DRM_LIST_NONE:
148 				drm_free_buffer(dev, dma->buflist[i]);
149 				break;
150 			case DRM_LIST_WAIT:
151 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
152 				break;
153 			default:
154 				/* Buffer already on hardware. */
155 				break;
156 			}
157 		}
158 	}
159 }
160 
161 EXPORT_SYMBOL(drm_core_reclaim_buffers);
162