Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License as published by the Free |
| 6 | * Software Foundation; either version 2 of the License, or (at your option) |
| 7 | * any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along with |
| 15 | * this program; if not, write to the Free Software Foundation, Inc., 59 |
| 16 | * Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | * |
| 18 | * The full GNU General Public License is included in this distribution in the |
| 19 | * file called COPYING. |
| 20 | */ |
| 21 | |
| 22 | /* |
| 23 | * This code implements the DMA subsystem. It provides a HW-neutral interface |
| 24 | * for other kernel code to use asynchronous memory copy capabilities, |
| 25 | * if present, and allows different HW DMA drivers to register as providing |
| 26 | * this capability. |
| 27 | * |
| 28 | * Due to the fact we are accelerating what is already a relatively fast |
| 29 | * operation, the code goes to great lengths to avoid additional overhead, |
| 30 | * such as locking. |
| 31 | * |
| 32 | * LOCKING: |
| 33 | * |
| 34 | * The subsystem keeps two global lists, dma_device_list and dma_client_list. |
| 35 | * Both of these are protected by a mutex, dma_list_mutex. |
| 36 | * |
| 37 | * Each device has a channels list, which runs unlocked but is never modified |
| 38 | * once the device is registered, it's just setup by the driver. |
| 39 | * |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 40 | * Each client is responsible for keeping track of the channels it uses. See |
| 41 | * the definition of dma_event_callback in dmaengine.h. |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 42 | * |
| 43 | * Each device has a kref, which is initialized to 1 when the device is |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 44 | * registered. A kref_get is done for each class_device registered. When the |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 45 | * class_device is released, the coresponding kref_put is done in the release |
| 46 | * method. Every time one of the device's channels is allocated to a client, |
| 47 | * a kref_get occurs. When the channel is freed, the coresponding kref_put |
| 48 | * happens. The device's release function does a completion, so |
| 49 | * unregister_device does a remove event, class_device_unregister, a kref_put |
| 50 | * for the first reference, then waits on the completion for all other |
| 51 | * references to finish. |
| 52 | * |
| 53 | * Each channel has an open-coded implementation of Rusty Russell's "bigref," |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 54 | * with a kref and a per_cpu local_t. A dma_chan_get is called when a client |
| 55 | * signals that it wants to use a channel, and dma_chan_put is called when |
| 56 | * a channel is removed or a client using it is unregesitered. A client can |
| 57 | * take extra references per outstanding transaction, as is the case with |
| 58 | * the NET DMA client. The release function does a kref_put on the device. |
| 59 | * -ChrisL, DanW |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 60 | */ |
| 61 | |
| 62 | #include <linux/init.h> |
| 63 | #include <linux/module.h> |
Dan Williams | 7405f74 | 2007-01-02 11:10:43 -0700 | [diff] [blame] | 64 | #include <linux/mm.h> |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 65 | #include <linux/device.h> |
| 66 | #include <linux/dmaengine.h> |
| 67 | #include <linux/hardirq.h> |
| 68 | #include <linux/spinlock.h> |
| 69 | #include <linux/percpu.h> |
| 70 | #include <linux/rcupdate.h> |
| 71 | #include <linux/mutex.h> |
Dan Williams | 7405f74 | 2007-01-02 11:10:43 -0700 | [diff] [blame] | 72 | #include <linux/jiffies.h> |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 73 | |
| 74 | static DEFINE_MUTEX(dma_list_mutex); |
| 75 | static LIST_HEAD(dma_device_list); |
| 76 | static LIST_HEAD(dma_client_list); |
| 77 | |
| 78 | /* --- sysfs implementation --- */ |
| 79 | |
| 80 | static ssize_t show_memcpy_count(struct class_device *cd, char *buf) |
| 81 | { |
| 82 | struct dma_chan *chan = container_of(cd, struct dma_chan, class_dev); |
| 83 | unsigned long count = 0; |
| 84 | int i; |
| 85 | |
Andrew Morton | 17f3ae0 | 2006-05-25 13:26:53 -0700 | [diff] [blame] | 86 | for_each_possible_cpu(i) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 87 | count += per_cpu_ptr(chan->local, i)->memcpy_count; |
| 88 | |
| 89 | return sprintf(buf, "%lu\n", count); |
| 90 | } |
| 91 | |
| 92 | static ssize_t show_bytes_transferred(struct class_device *cd, char *buf) |
| 93 | { |
| 94 | struct dma_chan *chan = container_of(cd, struct dma_chan, class_dev); |
| 95 | unsigned long count = 0; |
| 96 | int i; |
| 97 | |
Andrew Morton | 17f3ae0 | 2006-05-25 13:26:53 -0700 | [diff] [blame] | 98 | for_each_possible_cpu(i) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 99 | count += per_cpu_ptr(chan->local, i)->bytes_transferred; |
| 100 | |
| 101 | return sprintf(buf, "%lu\n", count); |
| 102 | } |
| 103 | |
| 104 | static ssize_t show_in_use(struct class_device *cd, char *buf) |
| 105 | { |
| 106 | struct dma_chan *chan = container_of(cd, struct dma_chan, class_dev); |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 107 | int in_use = 0; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 108 | |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 109 | if (unlikely(chan->slow_ref) && |
| 110 | atomic_read(&chan->refcount.refcount) > 1) |
| 111 | in_use = 1; |
| 112 | else { |
| 113 | if (local_read(&(per_cpu_ptr(chan->local, |
| 114 | get_cpu())->refcount)) > 0) |
| 115 | in_use = 1; |
| 116 | put_cpu(); |
| 117 | } |
| 118 | |
| 119 | return sprintf(buf, "%d\n", in_use); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 120 | } |
| 121 | |
| 122 | static struct class_device_attribute dma_class_attrs[] = { |
| 123 | __ATTR(memcpy_count, S_IRUGO, show_memcpy_count, NULL), |
| 124 | __ATTR(bytes_transferred, S_IRUGO, show_bytes_transferred, NULL), |
| 125 | __ATTR(in_use, S_IRUGO, show_in_use, NULL), |
| 126 | __ATTR_NULL |
| 127 | }; |
| 128 | |
| 129 | static void dma_async_device_cleanup(struct kref *kref); |
| 130 | |
| 131 | static void dma_class_dev_release(struct class_device *cd) |
| 132 | { |
| 133 | struct dma_chan *chan = container_of(cd, struct dma_chan, class_dev); |
| 134 | kref_put(&chan->device->refcount, dma_async_device_cleanup); |
| 135 | } |
| 136 | |
| 137 | static struct class dma_devclass = { |
| 138 | .name = "dma", |
| 139 | .class_dev_attrs = dma_class_attrs, |
| 140 | .release = dma_class_dev_release, |
| 141 | }; |
| 142 | |
| 143 | /* --- client and device registration --- */ |
| 144 | |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 145 | #define dma_chan_satisfies_mask(chan, mask) \ |
| 146 | __dma_chan_satisfies_mask((chan), &(mask)) |
| 147 | static int |
| 148 | __dma_chan_satisfies_mask(struct dma_chan *chan, dma_cap_mask_t *want) |
| 149 | { |
| 150 | dma_cap_mask_t has; |
| 151 | |
| 152 | bitmap_and(has.bits, want->bits, chan->device->cap_mask.bits, |
| 153 | DMA_TX_TYPE_END); |
| 154 | return bitmap_equal(want->bits, has.bits, DMA_TX_TYPE_END); |
| 155 | } |
| 156 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 157 | /** |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 158 | * dma_client_chan_alloc - try to allocate channels to a client |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 159 | * @client: &dma_client |
| 160 | * |
| 161 | * Called with dma_list_mutex held. |
| 162 | */ |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 163 | static void dma_client_chan_alloc(struct dma_client *client) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 164 | { |
| 165 | struct dma_device *device; |
| 166 | struct dma_chan *chan; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 167 | int desc; /* allocated descriptor count */ |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 168 | enum dma_state_client ack; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 169 | |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 170 | /* Find a channel */ |
| 171 | list_for_each_entry(device, &dma_device_list, global_node) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 172 | list_for_each_entry(chan, &device->channels, device_node) { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 173 | if (!dma_chan_satisfies_mask(chan, client->cap_mask)) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 174 | continue; |
| 175 | |
| 176 | desc = chan->device->device_alloc_chan_resources(chan); |
| 177 | if (desc >= 0) { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 178 | ack = client->event_callback(client, |
| 179 | chan, |
| 180 | DMA_RESOURCE_AVAILABLE); |
| 181 | |
| 182 | /* we are done once this client rejects |
| 183 | * an available resource |
| 184 | */ |
Haavard Skinnemoen | 348badf | 2007-11-14 16:59:27 -0800 | [diff] [blame^] | 185 | if (ack == DMA_ACK) |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 186 | dma_chan_get(chan); |
Haavard Skinnemoen | 348badf | 2007-11-14 16:59:27 -0800 | [diff] [blame^] | 187 | else if (ack == DMA_NAK) |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 188 | return; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 189 | } |
| 190 | } |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 191 | } |
| 192 | |
Dan Williams | 7405f74 | 2007-01-02 11:10:43 -0700 | [diff] [blame] | 193 | enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie) |
| 194 | { |
| 195 | enum dma_status status; |
| 196 | unsigned long dma_sync_wait_timeout = jiffies + msecs_to_jiffies(5000); |
| 197 | |
| 198 | dma_async_issue_pending(chan); |
| 199 | do { |
| 200 | status = dma_async_is_tx_complete(chan, cookie, NULL, NULL); |
| 201 | if (time_after_eq(jiffies, dma_sync_wait_timeout)) { |
| 202 | printk(KERN_ERR "dma_sync_wait_timeout!\n"); |
| 203 | return DMA_ERROR; |
| 204 | } |
| 205 | } while (status == DMA_IN_PROGRESS); |
| 206 | |
| 207 | return status; |
| 208 | } |
| 209 | EXPORT_SYMBOL(dma_sync_wait); |
| 210 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 211 | /** |
Randy Dunlap | 6508871 | 2006-07-03 19:45:31 -0700 | [diff] [blame] | 212 | * dma_chan_cleanup - release a DMA channel's resources |
| 213 | * @kref: kernel reference structure that contains the DMA channel device |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 214 | */ |
| 215 | void dma_chan_cleanup(struct kref *kref) |
| 216 | { |
| 217 | struct dma_chan *chan = container_of(kref, struct dma_chan, refcount); |
| 218 | chan->device->device_free_chan_resources(chan); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 219 | kref_put(&chan->device->refcount, dma_async_device_cleanup); |
| 220 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 221 | EXPORT_SYMBOL(dma_chan_cleanup); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 222 | |
| 223 | static void dma_chan_free_rcu(struct rcu_head *rcu) |
| 224 | { |
| 225 | struct dma_chan *chan = container_of(rcu, struct dma_chan, rcu); |
| 226 | int bias = 0x7FFFFFFF; |
| 227 | int i; |
Andrew Morton | 17f3ae0 | 2006-05-25 13:26:53 -0700 | [diff] [blame] | 228 | for_each_possible_cpu(i) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 229 | bias -= local_read(&per_cpu_ptr(chan->local, i)->refcount); |
| 230 | atomic_sub(bias, &chan->refcount.refcount); |
| 231 | kref_put(&chan->refcount, dma_chan_cleanup); |
| 232 | } |
| 233 | |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 234 | static void dma_chan_release(struct dma_chan *chan) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 235 | { |
| 236 | atomic_add(0x7FFFFFFF, &chan->refcount.refcount); |
| 237 | chan->slow_ref = 1; |
| 238 | call_rcu(&chan->rcu, dma_chan_free_rcu); |
| 239 | } |
| 240 | |
| 241 | /** |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 242 | * dma_chans_notify_available - broadcast available channels to the clients |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 243 | */ |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 244 | static void dma_clients_notify_available(void) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 245 | { |
| 246 | struct dma_client *client; |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 247 | |
| 248 | mutex_lock(&dma_list_mutex); |
| 249 | |
| 250 | list_for_each_entry(client, &dma_client_list, global_node) |
| 251 | dma_client_chan_alloc(client); |
| 252 | |
| 253 | mutex_unlock(&dma_list_mutex); |
| 254 | } |
| 255 | |
| 256 | /** |
| 257 | * dma_chans_notify_available - tell the clients that a channel is going away |
| 258 | * @chan: channel on its way out |
| 259 | */ |
| 260 | static void dma_clients_notify_removed(struct dma_chan *chan) |
| 261 | { |
| 262 | struct dma_client *client; |
| 263 | enum dma_state_client ack; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 264 | |
| 265 | mutex_lock(&dma_list_mutex); |
| 266 | |
| 267 | list_for_each_entry(client, &dma_client_list, global_node) { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 268 | ack = client->event_callback(client, chan, |
| 269 | DMA_RESOURCE_REMOVED); |
| 270 | |
| 271 | /* client was holding resources for this channel so |
| 272 | * free it |
| 273 | */ |
Haavard Skinnemoen | 348badf | 2007-11-14 16:59:27 -0800 | [diff] [blame^] | 274 | if (ack == DMA_ACK) |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 275 | dma_chan_put(chan); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 276 | } |
| 277 | |
| 278 | mutex_unlock(&dma_list_mutex); |
| 279 | } |
| 280 | |
| 281 | /** |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 282 | * dma_async_client_register - register a &dma_client |
| 283 | * @client: ptr to a client structure with valid 'event_callback' and 'cap_mask' |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 284 | */ |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 285 | void dma_async_client_register(struct dma_client *client) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 286 | { |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 287 | mutex_lock(&dma_list_mutex); |
| 288 | list_add_tail(&client->global_node, &dma_client_list); |
| 289 | mutex_unlock(&dma_list_mutex); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 290 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 291 | EXPORT_SYMBOL(dma_async_client_register); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 292 | |
| 293 | /** |
| 294 | * dma_async_client_unregister - unregister a client and free the &dma_client |
Randy Dunlap | 6508871 | 2006-07-03 19:45:31 -0700 | [diff] [blame] | 295 | * @client: &dma_client to free |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 296 | * |
| 297 | * Force frees any allocated DMA channels, frees the &dma_client memory |
| 298 | */ |
| 299 | void dma_async_client_unregister(struct dma_client *client) |
| 300 | { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 301 | struct dma_device *device; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 302 | struct dma_chan *chan; |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 303 | enum dma_state_client ack; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 304 | |
| 305 | if (!client) |
| 306 | return; |
| 307 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 308 | mutex_lock(&dma_list_mutex); |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 309 | /* free all channels the client is holding */ |
| 310 | list_for_each_entry(device, &dma_device_list, global_node) |
| 311 | list_for_each_entry(chan, &device->channels, device_node) { |
| 312 | ack = client->event_callback(client, chan, |
| 313 | DMA_RESOURCE_REMOVED); |
| 314 | |
Haavard Skinnemoen | 348badf | 2007-11-14 16:59:27 -0800 | [diff] [blame^] | 315 | if (ack == DMA_ACK) |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 316 | dma_chan_put(chan); |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 317 | } |
| 318 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 319 | list_del(&client->global_node); |
| 320 | mutex_unlock(&dma_list_mutex); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 321 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 322 | EXPORT_SYMBOL(dma_async_client_unregister); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 323 | |
| 324 | /** |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 325 | * dma_async_client_chan_request - send all available channels to the |
| 326 | * client that satisfy the capability mask |
| 327 | * @client - requester |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 328 | */ |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 329 | void dma_async_client_chan_request(struct dma_client *client) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 330 | { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 331 | mutex_lock(&dma_list_mutex); |
| 332 | dma_client_chan_alloc(client); |
| 333 | mutex_unlock(&dma_list_mutex); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 334 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 335 | EXPORT_SYMBOL(dma_async_client_chan_request); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 336 | |
| 337 | /** |
Randy Dunlap | 6508871 | 2006-07-03 19:45:31 -0700 | [diff] [blame] | 338 | * dma_async_device_register - registers DMA devices found |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 339 | * @device: &dma_device |
| 340 | */ |
| 341 | int dma_async_device_register(struct dma_device *device) |
| 342 | { |
| 343 | static int id; |
Jeff Garzik | ff487fb | 2007-03-08 09:57:34 -0800 | [diff] [blame] | 344 | int chancnt = 0, rc; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 345 | struct dma_chan* chan; |
| 346 | |
| 347 | if (!device) |
| 348 | return -ENODEV; |
| 349 | |
Dan Williams | 7405f74 | 2007-01-02 11:10:43 -0700 | [diff] [blame] | 350 | /* validate device routines */ |
| 351 | BUG_ON(dma_has_cap(DMA_MEMCPY, device->cap_mask) && |
| 352 | !device->device_prep_dma_memcpy); |
| 353 | BUG_ON(dma_has_cap(DMA_XOR, device->cap_mask) && |
| 354 | !device->device_prep_dma_xor); |
| 355 | BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) && |
| 356 | !device->device_prep_dma_zero_sum); |
| 357 | BUG_ON(dma_has_cap(DMA_MEMSET, device->cap_mask) && |
| 358 | !device->device_prep_dma_memset); |
| 359 | BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) && |
| 360 | !device->device_prep_dma_interrupt); |
| 361 | |
| 362 | BUG_ON(!device->device_alloc_chan_resources); |
| 363 | BUG_ON(!device->device_free_chan_resources); |
| 364 | BUG_ON(!device->device_dependency_added); |
| 365 | BUG_ON(!device->device_is_tx_complete); |
| 366 | BUG_ON(!device->device_issue_pending); |
| 367 | BUG_ON(!device->dev); |
| 368 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 369 | init_completion(&device->done); |
| 370 | kref_init(&device->refcount); |
| 371 | device->dev_id = id++; |
| 372 | |
| 373 | /* represent channels in sysfs. Probably want devs too */ |
| 374 | list_for_each_entry(chan, &device->channels, device_node) { |
| 375 | chan->local = alloc_percpu(typeof(*chan->local)); |
| 376 | if (chan->local == NULL) |
| 377 | continue; |
| 378 | |
| 379 | chan->chan_id = chancnt++; |
| 380 | chan->class_dev.class = &dma_devclass; |
| 381 | chan->class_dev.dev = NULL; |
| 382 | snprintf(chan->class_dev.class_id, BUS_ID_SIZE, "dma%dchan%d", |
| 383 | device->dev_id, chan->chan_id); |
| 384 | |
Jeff Garzik | ff487fb | 2007-03-08 09:57:34 -0800 | [diff] [blame] | 385 | rc = class_device_register(&chan->class_dev); |
| 386 | if (rc) { |
| 387 | chancnt--; |
| 388 | free_percpu(chan->local); |
| 389 | chan->local = NULL; |
| 390 | goto err_out; |
| 391 | } |
| 392 | |
Haavard Skinnemoen | 348badf | 2007-11-14 16:59:27 -0800 | [diff] [blame^] | 393 | /* One for the channel, one of the class device */ |
| 394 | kref_get(&device->refcount); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 395 | kref_get(&device->refcount); |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 396 | kref_init(&chan->refcount); |
| 397 | chan->slow_ref = 0; |
| 398 | INIT_RCU_HEAD(&chan->rcu); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 399 | } |
| 400 | |
| 401 | mutex_lock(&dma_list_mutex); |
| 402 | list_add_tail(&device->global_node, &dma_device_list); |
| 403 | mutex_unlock(&dma_list_mutex); |
| 404 | |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 405 | dma_clients_notify_available(); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 406 | |
| 407 | return 0; |
Jeff Garzik | ff487fb | 2007-03-08 09:57:34 -0800 | [diff] [blame] | 408 | |
| 409 | err_out: |
| 410 | list_for_each_entry(chan, &device->channels, device_node) { |
| 411 | if (chan->local == NULL) |
| 412 | continue; |
| 413 | kref_put(&device->refcount, dma_async_device_cleanup); |
| 414 | class_device_unregister(&chan->class_dev); |
| 415 | chancnt--; |
| 416 | free_percpu(chan->local); |
| 417 | } |
| 418 | return rc; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 419 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 420 | EXPORT_SYMBOL(dma_async_device_register); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 421 | |
| 422 | /** |
Randy Dunlap | 6508871 | 2006-07-03 19:45:31 -0700 | [diff] [blame] | 423 | * dma_async_device_cleanup - function called when all references are released |
| 424 | * @kref: kernel reference object |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 425 | */ |
| 426 | static void dma_async_device_cleanup(struct kref *kref) |
| 427 | { |
| 428 | struct dma_device *device; |
| 429 | |
| 430 | device = container_of(kref, struct dma_device, refcount); |
| 431 | complete(&device->done); |
| 432 | } |
| 433 | |
Randy Dunlap | 6508871 | 2006-07-03 19:45:31 -0700 | [diff] [blame] | 434 | /** |
| 435 | * dma_async_device_unregister - unregisters DMA devices |
| 436 | * @device: &dma_device |
| 437 | */ |
| 438 | void dma_async_device_unregister(struct dma_device *device) |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 439 | { |
| 440 | struct dma_chan *chan; |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 441 | |
| 442 | mutex_lock(&dma_list_mutex); |
| 443 | list_del(&device->global_node); |
| 444 | mutex_unlock(&dma_list_mutex); |
| 445 | |
| 446 | list_for_each_entry(chan, &device->channels, device_node) { |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 447 | dma_clients_notify_removed(chan); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 448 | class_device_unregister(&chan->class_dev); |
Dan Williams | d379b01 | 2007-07-09 11:56:42 -0700 | [diff] [blame] | 449 | dma_chan_release(chan); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 450 | } |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 451 | |
| 452 | kref_put(&device->refcount, dma_async_device_cleanup); |
| 453 | wait_for_completion(&device->done); |
| 454 | } |
David Brownell | 765e3d8 | 2007-03-16 13:38:05 -0800 | [diff] [blame] | 455 | EXPORT_SYMBOL(dma_async_device_unregister); |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 456 | |
Dan Williams | 7405f74 | 2007-01-02 11:10:43 -0700 | [diff] [blame] | 457 | /** |
| 458 | * dma_async_memcpy_buf_to_buf - offloaded copy between virtual addresses |
| 459 | * @chan: DMA channel to offload copy to |
| 460 | * @dest: destination address (virtual) |
| 461 | * @src: source address (virtual) |
| 462 | * @len: length |
| 463 | * |
| 464 | * Both @dest and @src must be mappable to a bus address according to the |
| 465 | * DMA mapping API rules for streaming mappings. |
| 466 | * Both @dest and @src must stay memory resident (kernel memory or locked |
| 467 | * user space pages). |
| 468 | */ |
| 469 | dma_cookie_t |
| 470 | dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest, |
| 471 | void *src, size_t len) |
| 472 | { |
| 473 | struct dma_device *dev = chan->device; |
| 474 | struct dma_async_tx_descriptor *tx; |
| 475 | dma_addr_t addr; |
| 476 | dma_cookie_t cookie; |
| 477 | int cpu; |
| 478 | |
| 479 | tx = dev->device_prep_dma_memcpy(chan, len, 0); |
| 480 | if (!tx) |
| 481 | return -ENOMEM; |
| 482 | |
| 483 | tx->ack = 1; |
| 484 | tx->callback = NULL; |
| 485 | addr = dma_map_single(dev->dev, src, len, DMA_TO_DEVICE); |
| 486 | tx->tx_set_src(addr, tx, 0); |
| 487 | addr = dma_map_single(dev->dev, dest, len, DMA_FROM_DEVICE); |
| 488 | tx->tx_set_dest(addr, tx, 0); |
| 489 | cookie = tx->tx_submit(tx); |
| 490 | |
| 491 | cpu = get_cpu(); |
| 492 | per_cpu_ptr(chan->local, cpu)->bytes_transferred += len; |
| 493 | per_cpu_ptr(chan->local, cpu)->memcpy_count++; |
| 494 | put_cpu(); |
| 495 | |
| 496 | return cookie; |
| 497 | } |
| 498 | EXPORT_SYMBOL(dma_async_memcpy_buf_to_buf); |
| 499 | |
| 500 | /** |
| 501 | * dma_async_memcpy_buf_to_pg - offloaded copy from address to page |
| 502 | * @chan: DMA channel to offload copy to |
| 503 | * @page: destination page |
| 504 | * @offset: offset in page to copy to |
| 505 | * @kdata: source address (virtual) |
| 506 | * @len: length |
| 507 | * |
| 508 | * Both @page/@offset and @kdata must be mappable to a bus address according |
| 509 | * to the DMA mapping API rules for streaming mappings. |
| 510 | * Both @page/@offset and @kdata must stay memory resident (kernel memory or |
| 511 | * locked user space pages) |
| 512 | */ |
| 513 | dma_cookie_t |
| 514 | dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page, |
| 515 | unsigned int offset, void *kdata, size_t len) |
| 516 | { |
| 517 | struct dma_device *dev = chan->device; |
| 518 | struct dma_async_tx_descriptor *tx; |
| 519 | dma_addr_t addr; |
| 520 | dma_cookie_t cookie; |
| 521 | int cpu; |
| 522 | |
| 523 | tx = dev->device_prep_dma_memcpy(chan, len, 0); |
| 524 | if (!tx) |
| 525 | return -ENOMEM; |
| 526 | |
| 527 | tx->ack = 1; |
| 528 | tx->callback = NULL; |
| 529 | addr = dma_map_single(dev->dev, kdata, len, DMA_TO_DEVICE); |
| 530 | tx->tx_set_src(addr, tx, 0); |
| 531 | addr = dma_map_page(dev->dev, page, offset, len, DMA_FROM_DEVICE); |
| 532 | tx->tx_set_dest(addr, tx, 0); |
| 533 | cookie = tx->tx_submit(tx); |
| 534 | |
| 535 | cpu = get_cpu(); |
| 536 | per_cpu_ptr(chan->local, cpu)->bytes_transferred += len; |
| 537 | per_cpu_ptr(chan->local, cpu)->memcpy_count++; |
| 538 | put_cpu(); |
| 539 | |
| 540 | return cookie; |
| 541 | } |
| 542 | EXPORT_SYMBOL(dma_async_memcpy_buf_to_pg); |
| 543 | |
| 544 | /** |
| 545 | * dma_async_memcpy_pg_to_pg - offloaded copy from page to page |
| 546 | * @chan: DMA channel to offload copy to |
| 547 | * @dest_pg: destination page |
| 548 | * @dest_off: offset in page to copy to |
| 549 | * @src_pg: source page |
| 550 | * @src_off: offset in page to copy from |
| 551 | * @len: length |
| 552 | * |
| 553 | * Both @dest_page/@dest_off and @src_page/@src_off must be mappable to a bus |
| 554 | * address according to the DMA mapping API rules for streaming mappings. |
| 555 | * Both @dest_page/@dest_off and @src_page/@src_off must stay memory resident |
| 556 | * (kernel memory or locked user space pages). |
| 557 | */ |
| 558 | dma_cookie_t |
| 559 | dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg, |
| 560 | unsigned int dest_off, struct page *src_pg, unsigned int src_off, |
| 561 | size_t len) |
| 562 | { |
| 563 | struct dma_device *dev = chan->device; |
| 564 | struct dma_async_tx_descriptor *tx; |
| 565 | dma_addr_t addr; |
| 566 | dma_cookie_t cookie; |
| 567 | int cpu; |
| 568 | |
| 569 | tx = dev->device_prep_dma_memcpy(chan, len, 0); |
| 570 | if (!tx) |
| 571 | return -ENOMEM; |
| 572 | |
| 573 | tx->ack = 1; |
| 574 | tx->callback = NULL; |
| 575 | addr = dma_map_page(dev->dev, src_pg, src_off, len, DMA_TO_DEVICE); |
| 576 | tx->tx_set_src(addr, tx, 0); |
| 577 | addr = dma_map_page(dev->dev, dest_pg, dest_off, len, DMA_FROM_DEVICE); |
| 578 | tx->tx_set_dest(addr, tx, 0); |
| 579 | cookie = tx->tx_submit(tx); |
| 580 | |
| 581 | cpu = get_cpu(); |
| 582 | per_cpu_ptr(chan->local, cpu)->bytes_transferred += len; |
| 583 | per_cpu_ptr(chan->local, cpu)->memcpy_count++; |
| 584 | put_cpu(); |
| 585 | |
| 586 | return cookie; |
| 587 | } |
| 588 | EXPORT_SYMBOL(dma_async_memcpy_pg_to_pg); |
| 589 | |
| 590 | void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx, |
| 591 | struct dma_chan *chan) |
| 592 | { |
| 593 | tx->chan = chan; |
| 594 | spin_lock_init(&tx->lock); |
| 595 | INIT_LIST_HEAD(&tx->depend_node); |
| 596 | INIT_LIST_HEAD(&tx->depend_list); |
| 597 | } |
| 598 | EXPORT_SYMBOL(dma_async_tx_descriptor_init); |
| 599 | |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 600 | static int __init dma_bus_init(void) |
| 601 | { |
| 602 | mutex_init(&dma_list_mutex); |
| 603 | return class_register(&dma_devclass); |
| 604 | } |
Chris Leech | c13c826 | 2006-05-23 17:18:44 -0700 | [diff] [blame] | 605 | subsys_initcall(dma_bus_init); |
| 606 | |