summaryrefslogtreecommitdiff
path: root/drivers/gpu/host1x/channel.c
blob: 2fb93c27c1d9dc05802f4509caf2f952b2db0e97 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
/*
 * Tegra host1x Channel
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/slab.h>
#include <linux/module.h>

#include "channel.h"
#include "dev.h"
#include "job.h"

/* Constructor for the host1x device list */
int host1x_channel_list_init(struct host1x_channel_list *chlist,
			     unsigned int num_channels)
{
	chlist->channels = kcalloc(num_channels, sizeof(struct host1x_channel),
				   GFP_KERNEL);
	if (!chlist->channels)
		return -ENOMEM;

	chlist->allocated_channels =
		kcalloc(BITS_TO_LONGS(num_channels), sizeof(unsigned long),
			GFP_KERNEL);
	if (!chlist->allocated_channels) {
		kfree(chlist->channels);
		return -ENOMEM;
	}

	bitmap_zero(chlist->allocated_channels, num_channels);

	return 0;
}

void host1x_channel_list_free(struct host1x_channel_list *chlist)
{
	kfree(chlist->allocated_channels);
	kfree(chlist->channels);
}

int host1x_job_submit(struct host1x_job *job)
{
	struct host1x *host = dev_get_drvdata(job->channel->dev->parent);

	return host1x_hw_channel_submit(host, job);
}
EXPORT_SYMBOL(host1x_job_submit);

struct host1x_channel *host1x_channel_get(struct host1x_channel *channel)
{
	kref_get(&channel->refcount);

	return channel;
}
EXPORT_SYMBOL(host1x_channel_get);

/**
 * host1x_channel_get_index() - Attempt to get channel reference by index
 * @host: Host1x device object
 * @index: Index of channel
 *
 * If channel number @index is currently allocated, increase its refcount
 * and return a pointer to it. Otherwise, return NULL.
 */
struct host1x_channel *host1x_channel_get_index(struct host1x *host,
						unsigned int index)
{
	struct host1x_channel *ch = &host->channel_list.channels[index];

	if (!kref_get_unless_zero(&ch->refcount))
		return NULL;

	return ch;
}

static void release_channel(struct kref *kref)
{
	struct host1x_channel *channel =
		container_of(kref, struct host1x_channel, refcount);
	struct host1x *host = dev_get_drvdata(channel->dev->parent);
	struct host1x_channel_list *chlist = &host->channel_list;

	host1x_hw_cdma_stop(host, &channel->cdma);
	host1x_cdma_deinit(&channel->cdma);

	clear_bit(channel->id, chlist->allocated_channels);
}

void host1x_channel_put(struct host1x_channel *channel)
{
	kref_put(&channel->refcount, release_channel);
}
EXPORT_SYMBOL(host1x_channel_put);

static struct host1x_channel *acquire_unused_channel(struct host1x *host)
{
	struct host1x_channel_list *chlist = &host->channel_list;
	unsigned int max_channels = host->info->nb_channels;
	unsigned int index;

	index = find_first_zero_bit(chlist->allocated_channels, max_channels);
	if (index >= max_channels) {
		dev_err(host->dev, "failed to find free channel\n");
		return NULL;
	}

	chlist->channels[index].id = index;

	set_bit(index, chlist->allocated_channels);

	return &chlist->channels[index];
}

/**
 * host1x_channel_request() - Allocate a channel
 * @device: Host1x unit this channel will be used to send commands to
 *
 * Allocates a new host1x channel for @device. May return NULL if CDMA
 * initialization fails.
 */
struct host1x_channel *host1x_channel_request(struct device *dev)
{
	struct host1x *host = dev_get_drvdata(dev->parent);
	struct host1x_channel_list *chlist = &host->channel_list;
	struct host1x_channel *channel;
	int err;

	channel = acquire_unused_channel(host);
	if (!channel)
		return NULL;

	kref_init(&channel->refcount);
	mutex_init(&channel->submitlock);
	channel->dev = dev;

	err = host1x_hw_channel_init(host, channel, channel->id);
	if (err < 0)
		goto fail;

	err = host1x_cdma_init(&channel->cdma);
	if (err < 0)
		goto fail;

	return channel;

fail:
	clear_bit(channel->id, chlist->allocated_channels);

	dev_err(dev, "failed to initialize channel\n");

	return NULL;
}
EXPORT_SYMBOL(host1x_channel_request);