xref: /openbmc/linux/drivers/gpu/drm/drm_dma.c (revision a09d2831)
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 = kmalloc(sizeof(*dev->dma), GFP_KERNEL);
51 	if (!dev->dma)
52 		return -ENOMEM;
53 
54 	memset(dev->dma, 0, sizeof(*dev->dma));
55 
56 	for (i = 0; i <= DRM_MAX_ORDER; i++)
57 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
58 
59 	return 0;
60 }
61 
62 /**
63  * Cleanup the DMA resources.
64  *
65  * \param dev DRM device.
66  *
67  * Free all pages associated with DMA buffers, the buffers and pages lists, and
68  * finally the drm_device::dma structure itself.
69  */
70 void drm_dma_takedown(struct drm_device *dev)
71 {
72 	struct drm_device_dma *dma = dev->dma;
73 	int i, j;
74 
75 	if (!dma)
76 		return;
77 
78 	/* Clear dma buffers */
79 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
80 		if (dma->bufs[i].seg_count) {
81 			DRM_DEBUG("order %d: buf_count = %d,"
82 				  " seg_count = %d\n",
83 				  i,
84 				  dma->bufs[i].buf_count,
85 				  dma->bufs[i].seg_count);
86 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
87 				if (dma->bufs[i].seglist[j]) {
88 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
89 				}
90 			}
91 			kfree(dma->bufs[i].seglist);
92 		}
93 		if (dma->bufs[i].buf_count) {
94 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
95 				kfree(dma->bufs[i].buflist[j].dev_private);
96 			}
97 			kfree(dma->bufs[i].buflist);
98 		}
99 	}
100 
101 	kfree(dma->buflist);
102 	kfree(dma->pagelist);
103 	kfree(dev->dma);
104 	dev->dma = NULL;
105 }
106 
107 /**
108  * Free a buffer.
109  *
110  * \param dev DRM device.
111  * \param buf buffer to free.
112  *
113  * Resets the fields of \p buf.
114  */
115 void drm_free_buffer(struct drm_device *dev, struct drm_buf * buf)
116 {
117 	if (!buf)
118 		return;
119 
120 	buf->waiting = 0;
121 	buf->pending = 0;
122 	buf->file_priv = NULL;
123 	buf->used = 0;
124 
125 	if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE)
126 	    && waitqueue_active(&buf->dma_wait)) {
127 		wake_up_interruptible(&buf->dma_wait);
128 	}
129 }
130 
131 /**
132  * Reclaim the buffers.
133  *
134  * \param file_priv DRM file private.
135  *
136  * Frees each buffer associated with \p file_priv not already on the hardware.
137  */
138 void drm_core_reclaim_buffers(struct drm_device *dev,
139 			      struct drm_file *file_priv)
140 {
141 	struct drm_device_dma *dma = dev->dma;
142 	int i;
143 
144 	if (!dma)
145 		return;
146 	for (i = 0; i < dma->buf_count; i++) {
147 		if (dma->buflist[i]->file_priv == file_priv) {
148 			switch (dma->buflist[i]->list) {
149 			case DRM_LIST_NONE:
150 				drm_free_buffer(dev, dma->buflist[i]);
151 				break;
152 			case DRM_LIST_WAIT:
153 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
154 				break;
155 			default:
156 				/* Buffer already on hardware. */
157 				break;
158 			}
159 		}
160 	}
161 }
162 
163 EXPORT_SYMBOL(drm_core_reclaim_buffers);
164