xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_dma.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$NetBSD: drm_dma.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $	*/
2 
3 /**
4  * \file drm_dma.c
5  * DMA IOCTL and function support
6  *
7  * \author Rickard E. (Rik) Faith <faith@valinux.com>
8  * \author Gareth Hughes <gareth@valinux.com>
9  */
10 
11 /*
12  * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
13  *
14  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
15  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
16  * All Rights Reserved.
17  *
18  * Permission is hereby granted, free of charge, to any person obtaining a
19  * copy of this software and associated documentation files (the "Software"),
20  * to deal in the Software without restriction, including without limitation
21  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
22  * and/or sell copies of the Software, and to permit persons to whom the
23  * Software is furnished to do so, subject to the following conditions:
24  *
25  * The above copyright notice and this permission notice (including the next
26  * paragraph) shall be included in all copies or substantial portions of the
27  * Software.
28  *
29  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
30  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
31  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
32  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
33  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
34  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
35  * OTHER DEALINGS IN THE SOFTWARE.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: drm_dma.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $");
40 
41 #include <linux/export.h>
42 #include <drm/drmP.h>
43 #include "drm_legacy.h"
44 
45 /**
46  * Initialize the DMA data.
47  *
48  * \param dev DRM device.
49  * \return zero on success or a negative value on failure.
50  *
51  * Allocate and initialize a drm_device_dma structure.
52  */
53 int drm_legacy_dma_setup(struct drm_device *dev)
54 {
55 	int i;
56 
57 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
58 	    drm_core_check_feature(dev, DRIVER_MODESET)) {
59 		return 0;
60 	}
61 
62 	dev->buf_use = 0;
63 	atomic_set(&dev->buf_alloc, 0);
64 
65 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
66 	if (!dev->dma)
67 		return -ENOMEM;
68 
69 	for (i = 0; i <= DRM_MAX_ORDER; i++)
70 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
71 
72 	return 0;
73 }
74 
75 /**
76  * Cleanup the DMA resources.
77  *
78  * \param dev DRM device.
79  *
80  * Free all pages associated with DMA buffers, the buffers and pages lists, and
81  * finally the drm_device::dma structure itself.
82  */
83 void drm_legacy_dma_takedown(struct drm_device *dev)
84 {
85 	struct drm_device_dma *dma = dev->dma;
86 	int i, j;
87 
88 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
89 	    drm_core_check_feature(dev, DRIVER_MODESET)) {
90 		return;
91 	}
92 
93 	if (!dma)
94 		return;
95 
96 	/* Clear dma buffers */
97 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
98 		if (dma->bufs[i].seg_count) {
99 			DRM_DEBUG("order %d: buf_count = %d,"
100 				  " seg_count = %d\n",
101 				  i,
102 				  dma->bufs[i].buf_count,
103 				  dma->bufs[i].seg_count);
104 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
105 				if (dma->bufs[i].seglist[j]) {
106 					drm_pci_free(dev, dma->bufs[i].seglist[j]);
107 				}
108 			}
109 			kfree(dma->bufs[i].seglist);
110 		}
111 		if (dma->bufs[i].buf_count) {
112 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
113 				kfree(dma->bufs[i].buflist[j].dev_private);
114 			}
115 			kfree(dma->bufs[i].buflist);
116 		}
117 	}
118 
119 	kfree(dma->buflist);
120 	kfree(dma->pagelist);
121 	kfree(dev->dma);
122 	dev->dma = NULL;
123 }
124 
125 /**
126  * Free a buffer.
127  *
128  * \param dev DRM device.
129  * \param buf buffer to free.
130  *
131  * Resets the fields of \p buf.
132  */
133 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
134 {
135 	if (!buf)
136 		return;
137 
138 	buf->waiting = 0;
139 	buf->pending = 0;
140 	buf->file_priv = NULL;
141 	buf->used = 0;
142 }
143 
144 /**
145  * Reclaim the buffers.
146  *
147  * \param file_priv DRM file private.
148  *
149  * Frees each buffer associated with \p file_priv not already on the hardware.
150  */
151 void drm_legacy_reclaim_buffers(struct drm_device *dev,
152 				struct drm_file *file_priv)
153 {
154 	struct drm_device_dma *dma = dev->dma;
155 	int i;
156 
157 	if (!dma)
158 		return;
159 	for (i = 0; i < dma->buf_count; i++) {
160 		if (dma->buflist[i]->file_priv == file_priv) {
161 			switch (dma->buflist[i]->list) {
162 			case DRM_LIST_NONE:
163 				drm_legacy_free_buffer(dev, dma->buflist[i]);
164 				break;
165 			case DRM_LIST_WAIT:
166 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
167 				break;
168 			default:
169 				/* Buffer already on hardware. */
170 				break;
171 			}
172 		}
173 	}
174 }
175