1/*
2 * Tegra host1x Channel
3 *
4 * Copyright (c) 2010-2013, NVIDIA Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include <linux/slab.h>
20#include <linux/module.h>
21
22#include "channel.h"
23#include "dev.h"
24#include "job.h"
25
26/* Constructor for the host1x device list */
27int host1x_channel_list_init(struct host1x *host)
28{
29	INIT_LIST_HEAD(&host->chlist.list);
30	mutex_init(&host->chlist_mutex);
31
32	if (host->info->nb_channels > BITS_PER_LONG) {
33		WARN(1, "host1x hardware has more channels than supported by the driver\n");
34		return -ENOSYS;
35	}
36
37	return 0;
38}
39
40int host1x_job_submit(struct host1x_job *job)
41{
42	struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
43
44	return host1x_hw_channel_submit(host, job);
45}
46EXPORT_SYMBOL(host1x_job_submit);
47
48struct host1x_channel *host1x_channel_get(struct host1x_channel *channel)
49{
50	int err = 0;
51
52	mutex_lock(&channel->reflock);
53
54	if (channel->refcount == 0)
55		err = host1x_cdma_init(&channel->cdma);
56
57	if (!err)
58		channel->refcount++;
59
60	mutex_unlock(&channel->reflock);
61
62	return err ? NULL : channel;
63}
64EXPORT_SYMBOL(host1x_channel_get);
65
66void host1x_channel_put(struct host1x_channel *channel)
67{
68	mutex_lock(&channel->reflock);
69
70	if (channel->refcount == 1) {
71		struct host1x *host = dev_get_drvdata(channel->dev->parent);
72
73		host1x_hw_cdma_stop(host, &channel->cdma);
74		host1x_cdma_deinit(&channel->cdma);
75	}
76
77	channel->refcount--;
78
79	mutex_unlock(&channel->reflock);
80}
81EXPORT_SYMBOL(host1x_channel_put);
82
83struct host1x_channel *host1x_channel_request(struct device *dev)
84{
85	struct host1x *host = dev_get_drvdata(dev->parent);
86	int max_channels = host->info->nb_channels;
87	struct host1x_channel *channel = NULL;
88	int index, err;
89
90	mutex_lock(&host->chlist_mutex);
91
92	index = find_first_zero_bit(&host->allocated_channels, max_channels);
93	if (index >= max_channels)
94		goto fail;
95
96	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
97	if (!channel)
98		goto fail;
99
100	err = host1x_hw_channel_init(host, channel, index);
101	if (err < 0)
102		goto fail;
103
104	/* Link device to host1x_channel */
105	channel->dev = dev;
106
107	/* Add to channel list */
108	list_add_tail(&channel->list, &host->chlist.list);
109
110	host->allocated_channels |= BIT(index);
111
112	mutex_unlock(&host->chlist_mutex);
113	return channel;
114
115fail:
116	dev_err(dev, "failed to init channel\n");
117	kfree(channel);
118	mutex_unlock(&host->chlist_mutex);
119	return NULL;
120}
121EXPORT_SYMBOL(host1x_channel_request);
122
123void host1x_channel_free(struct host1x_channel *channel)
124{
125	struct host1x *host = dev_get_drvdata(channel->dev->parent);
126
127	host->allocated_channels &= ~BIT(channel->id);
128	list_del(&channel->list);
129	kfree(channel);
130}
131EXPORT_SYMBOL(host1x_channel_free);
132