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 */ 27 int 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 40 int 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 } 46 47 struct host1x_channel *host1x_channel_get(struct host1x_channel *channel) 48 { 49 int err = 0; 50 51 mutex_lock(&channel->reflock); 52 53 if (channel->refcount == 0) 54 err = host1x_cdma_init(&channel->cdma); 55 56 if (!err) 57 channel->refcount++; 58 59 mutex_unlock(&channel->reflock); 60 61 return err ? NULL : channel; 62 } 63 64 void host1x_channel_put(struct host1x_channel *channel) 65 { 66 mutex_lock(&channel->reflock); 67 68 if (channel->refcount == 1) { 69 struct host1x *host = dev_get_drvdata(channel->dev->parent); 70 71 host1x_hw_cdma_stop(host, &channel->cdma); 72 host1x_cdma_deinit(&channel->cdma); 73 } 74 75 channel->refcount--; 76 77 mutex_unlock(&channel->reflock); 78 } 79 80 struct host1x_channel *host1x_channel_request(struct device *dev) 81 { 82 struct host1x *host = dev_get_drvdata(dev->parent); 83 int max_channels = host->info->nb_channels; 84 struct host1x_channel *channel = NULL; 85 int index, err; 86 87 mutex_lock(&host->chlist_mutex); 88 89 index = find_first_zero_bit(&host->allocated_channels, max_channels); 90 if (index >= max_channels) 91 goto fail; 92 93 channel = kzalloc(sizeof(*channel), GFP_KERNEL); 94 if (!channel) 95 goto fail; 96 97 err = host1x_hw_channel_init(host, channel, index); 98 if (err < 0) 99 goto fail; 100 101 /* Link device to host1x_channel */ 102 channel->dev = dev; 103 104 /* Add to channel list */ 105 list_add_tail(&channel->list, &host->chlist.list); 106 107 host->allocated_channels |= BIT(index); 108 109 mutex_unlock(&host->chlist_mutex); 110 return channel; 111 112 fail: 113 dev_err(dev, "failed to init channel\n"); 114 kfree(channel); 115 mutex_unlock(&host->chlist_mutex); 116 return NULL; 117 } 118 119 void host1x_channel_free(struct host1x_channel *channel) 120 { 121 struct host1x *host = dev_get_drvdata(channel->dev->parent); 122 123 host->allocated_channels &= ~BIT(channel->id); 124 list_del(&channel->list); 125 kfree(channel); 126 } 127