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185 lines · 4.4 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Tegra host1x Channel
4 *
5 * Copyright (c) 2010-2013, NVIDIA Corporation.
6 */
7
8#include <linux/slab.h>
9#include <linux/module.h>
10
11#include "channel.h"
12#include "dev.h"
13#include "job.h"
14
15/* Constructor for the host1x device list */
16int host1x_channel_list_init(struct host1x_channel_list *chlist,
17 unsigned int num_channels)
18{
19 chlist->channels = kzalloc_objs(struct host1x_channel, num_channels);
20 if (!chlist->channels)
21 return -ENOMEM;
22
23 chlist->allocated_channels = bitmap_zalloc(num_channels, GFP_KERNEL);
24 if (!chlist->allocated_channels) {
25 kfree(chlist->channels);
26 return -ENOMEM;
27 }
28
29 mutex_init(&chlist->lock);
30
31 return 0;
32}
33
34void host1x_channel_list_free(struct host1x_channel_list *chlist)
35{
36 bitmap_free(chlist->allocated_channels);
37 kfree(chlist->channels);
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 kref_get(&channel->refcount);
51
52 return channel;
53}
54EXPORT_SYMBOL(host1x_channel_get);
55
56/**
57 * host1x_channel_get_index() - Attempt to get channel reference by index
58 * @host: Host1x device object
59 * @index: Index of channel
60 *
61 * If channel number @index is currently allocated, increase its refcount
62 * and return a pointer to it. Otherwise, return NULL.
63 */
64struct host1x_channel *host1x_channel_get_index(struct host1x *host,
65 unsigned int index)
66{
67 struct host1x_channel *ch = &host->channel_list.channels[index];
68
69 if (!kref_get_unless_zero(&ch->refcount))
70 return NULL;
71
72 return ch;
73}
74
75void host1x_channel_stop(struct host1x_channel *channel)
76{
77 struct host1x *host = dev_get_drvdata(channel->dev->parent);
78
79 host1x_hw_cdma_stop(host, &channel->cdma);
80}
81EXPORT_SYMBOL(host1x_channel_stop);
82
83/**
84 * host1x_channel_stop_all() - disable CDMA on allocated channels
85 * @host: host1x instance
86 *
87 * Stop CDMA on allocated channels
88 */
89void host1x_channel_stop_all(struct host1x *host)
90{
91 struct host1x_channel_list *chlist = &host->channel_list;
92 int bit;
93
94 mutex_lock(&chlist->lock);
95
96 for_each_set_bit(bit, chlist->allocated_channels, host->info->nb_channels)
97 host1x_channel_stop(&chlist->channels[bit]);
98
99 mutex_unlock(&chlist->lock);
100}
101
102static void release_channel(struct kref *kref)
103{
104 struct host1x_channel *channel =
105 container_of(kref, struct host1x_channel, refcount);
106 struct host1x *host = dev_get_drvdata(channel->dev->parent);
107 struct host1x_channel_list *chlist = &host->channel_list;
108
109 host1x_hw_cdma_stop(host, &channel->cdma);
110 host1x_cdma_deinit(&channel->cdma);
111
112 clear_bit(channel->id, chlist->allocated_channels);
113}
114
115void host1x_channel_put(struct host1x_channel *channel)
116{
117 kref_put(&channel->refcount, release_channel);
118}
119EXPORT_SYMBOL(host1x_channel_put);
120
121static struct host1x_channel *acquire_unused_channel(struct host1x *host)
122{
123 struct host1x_channel_list *chlist = &host->channel_list;
124 unsigned int max_channels = host->info->nb_channels;
125 unsigned int index;
126
127 mutex_lock(&chlist->lock);
128
129 index = find_first_zero_bit(chlist->allocated_channels, max_channels);
130 if (index >= max_channels) {
131 mutex_unlock(&chlist->lock);
132 dev_err(host->dev, "failed to find free channel\n");
133 return NULL;
134 }
135
136 chlist->channels[index].id = index;
137
138 set_bit(index, chlist->allocated_channels);
139
140 mutex_unlock(&chlist->lock);
141
142 return &chlist->channels[index];
143}
144
145/**
146 * host1x_channel_request() - Allocate a channel
147 * @client: Host1x client this channel will be used to send commands to
148 *
149 * Allocates a new host1x channel for @client. May return NULL if CDMA
150 * initialization fails.
151 */
152struct host1x_channel *host1x_channel_request(struct host1x_client *client)
153{
154 struct host1x *host = dev_get_drvdata(client->dev->parent);
155 struct host1x_channel_list *chlist = &host->channel_list;
156 struct host1x_channel *channel;
157 int err;
158
159 channel = acquire_unused_channel(host);
160 if (!channel)
161 return NULL;
162
163 kref_init(&channel->refcount);
164 mutex_init(&channel->submitlock);
165 channel->client = client;
166 channel->dev = client->dev;
167
168 err = host1x_hw_channel_init(host, channel, channel->id);
169 if (err < 0)
170 goto fail;
171
172 err = host1x_cdma_init(&channel->cdma);
173 if (err < 0)
174 goto fail;
175
176 return channel;
177
178fail:
179 clear_bit(channel->id, chlist->allocated_channels);
180
181 dev_err(client->dev, "failed to initialize channel\n");
182
183 return NULL;
184}
185EXPORT_SYMBOL(host1x_channel_request);