xref: /openbmc/linux/drivers/gpu/drm/drm_dma.c (revision e3b9f1e8)
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_LEGACY))
54 		return 0;
55 
56 	dev->buf_use = 0;
57 	atomic_set(&dev->buf_alloc, 0);
58 
59 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
60 	if (!dev->dma)
61 		return -ENOMEM;
62 
63 	for (i = 0; i <= DRM_MAX_ORDER; i++)
64 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
65 
66 	return 0;
67 }
68 
69 /**
70  * Cleanup the DMA resources.
71  *
72  * \param dev DRM device.
73  *
74  * Free all pages associated with DMA buffers, the buffers and pages lists, and
75  * finally the drm_device::dma structure itself.
76  */
77 void drm_legacy_dma_takedown(struct drm_device *dev)
78 {
79 	struct drm_device_dma *dma = dev->dma;
80 	int i, j;
81 
82 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
83 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
84 		return;
85 
86 	if (!dma)
87 		return;
88 
89 	/* Clear dma buffers */
90 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
91 		if (dma->bufs[i].seg_count) {
92 			DRM_DEBUG("order %d: buf_count = %d,"
93 				  " seg_count = %d\n",
94 				  i,
95 				  dma->bufs[i].buf_count,
96 				  dma->bufs[i].seg_count);
97 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
98 				if (dma->bufs[i].seglist[j]) {
99 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
100 				}
101 			}
102 			kfree(dma->bufs[i].seglist);
103 		}
104 		if (dma->bufs[i].buf_count) {
105 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
106 				kfree(dma->bufs[i].buflist[j].dev_private);
107 			}
108 			kfree(dma->bufs[i].buflist);
109 		}
110 	}
111 
112 	kfree(dma->buflist);
113 	kfree(dma->pagelist);
114 	kfree(dev->dma);
115 	dev->dma = NULL;
116 }
117 
118 /**
119  * Free a buffer.
120  *
121  * \param dev DRM device.
122  * \param buf buffer to free.
123  *
124  * Resets the fields of \p buf.
125  */
126 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
127 {
128 	if (!buf)
129 		return;
130 
131 	buf->waiting = 0;
132 	buf->pending = 0;
133 	buf->file_priv = NULL;
134 	buf->used = 0;
135 }
136 
137 /**
138  * Reclaim the buffers.
139  *
140  * \param file_priv DRM file private.
141  *
142  * Frees each buffer associated with \p file_priv not already on the hardware.
143  */
144 void drm_legacy_reclaim_buffers(struct drm_device *dev,
145 				struct drm_file *file_priv)
146 {
147 	struct drm_device_dma *dma = dev->dma;
148 	int i;
149 
150 	if (!dma)
151 		return;
152 	for (i = 0; i < dma->buf_count; i++) {
153 		if (dma->buflist[i]->file_priv == file_priv) {
154 			switch (dma->buflist[i]->list) {
155 			case DRM_LIST_NONE:
156 				drm_legacy_free_buffer(dev, dma->buflist[i]);
157 				break;
158 			case DRM_LIST_WAIT:
159 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
160 				break;
161 			default:
162 				/* Buffer already on hardware. */
163 				break;
164 			}
165 		}
166 	}
167 }
168