xref: /openbmc/linux/drivers/gpu/drm/drm_dma.c (revision 9cfc5c90)
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 #include "drm_legacy.h"
39 
40 /**
41  * Initialize the DMA data.
42  *
43  * \param dev DRM device.
44  * \return zero on success or a negative value on failure.
45  *
46  * Allocate and initialize a drm_device_dma structure.
47  */
48 int drm_legacy_dma_setup(struct drm_device *dev)
49 {
50 	int i;
51 
52 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
53 	    drm_core_check_feature(dev, DRIVER_MODESET)) {
54 		return 0;
55 	}
56 
57 	dev->buf_use = 0;
58 	atomic_set(&dev->buf_alloc, 0);
59 
60 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
61 	if (!dev->dma)
62 		return -ENOMEM;
63 
64 	for (i = 0; i <= DRM_MAX_ORDER; i++)
65 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
66 
67 	return 0;
68 }
69 
70 /**
71  * Cleanup the DMA resources.
72  *
73  * \param dev DRM device.
74  *
75  * Free all pages associated with DMA buffers, the buffers and pages lists, and
76  * finally the drm_device::dma structure itself.
77  */
78 void drm_legacy_dma_takedown(struct drm_device *dev)
79 {
80 	struct drm_device_dma *dma = dev->dma;
81 	int i, j;
82 
83 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
84 	    drm_core_check_feature(dev, DRIVER_MODESET)) {
85 		return;
86 	}
87 
88 	if (!dma)
89 		return;
90 
91 	/* Clear dma buffers */
92 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
93 		if (dma->bufs[i].seg_count) {
94 			DRM_DEBUG("order %d: buf_count = %d,"
95 				  " seg_count = %d\n",
96 				  i,
97 				  dma->bufs[i].buf_count,
98 				  dma->bufs[i].seg_count);
99 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
100 				if (dma->bufs[i].seglist[j]) {
101 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
102 				}
103 			}
104 			kfree(dma->bufs[i].seglist);
105 		}
106 		if (dma->bufs[i].buf_count) {
107 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
108 				kfree(dma->bufs[i].buflist[j].dev_private);
109 			}
110 			kfree(dma->bufs[i].buflist);
111 		}
112 	}
113 
114 	kfree(dma->buflist);
115 	kfree(dma->pagelist);
116 	kfree(dev->dma);
117 	dev->dma = NULL;
118 }
119 
120 /**
121  * Free a buffer.
122  *
123  * \param dev DRM device.
124  * \param buf buffer to free.
125  *
126  * Resets the fields of \p buf.
127  */
128 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
129 {
130 	if (!buf)
131 		return;
132 
133 	buf->waiting = 0;
134 	buf->pending = 0;
135 	buf->file_priv = NULL;
136 	buf->used = 0;
137 }
138 
139 /**
140  * Reclaim the buffers.
141  *
142  * \param file_priv DRM file private.
143  *
144  * Frees each buffer associated with \p file_priv not already on the hardware.
145  */
146 void drm_legacy_reclaim_buffers(struct drm_device *dev,
147 				struct drm_file *file_priv)
148 {
149 	struct drm_device_dma *dma = dev->dma;
150 	int i;
151 
152 	if (!dma)
153 		return;
154 	for (i = 0; i < dma->buf_count; i++) {
155 		if (dma->buflist[i]->file_priv == file_priv) {
156 			switch (dma->buflist[i]->list) {
157 			case DRM_LIST_NONE:
158 				drm_legacy_free_buffer(dev, dma->buflist[i]);
159 				break;
160 			case DRM_LIST_WAIT:
161 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
162 				break;
163 			default:
164 				/* Buffer already on hardware. */
165 				break;
166 			}
167 		}
168 	}
169 }
170