2 * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
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)
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
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.
18 * The full GNU General Public License is included in this distribution in the
19 * file called COPYING.
23 * This driver supports an interface for DCA clients and providers to meet.
26 #include <linux/kernel.h>
27 #include <linux/notifier.h>
28 #include <linux/device.h>
29 #include <linux/dca.h>
30 #include <linux/slab.h>
32 #define DCA_VERSION "1.12.1"
34 MODULE_VERSION(DCA_VERSION
);
35 MODULE_LICENSE("GPL");
36 MODULE_AUTHOR("Intel Corporation");
38 static DEFINE_RAW_SPINLOCK(dca_lock
);
40 static LIST_HEAD(dca_domains
);
42 static BLOCKING_NOTIFIER_HEAD(dca_provider_chain
);
44 static int dca_providers_blocked
;
46 static struct pci_bus
*dca_pci_rc_from_dev(struct device
*dev
)
48 struct pci_dev
*pdev
= to_pci_dev(dev
);
49 struct pci_bus
*bus
= pdev
->bus
;
57 static struct dca_domain
*dca_allocate_domain(struct pci_bus
*rc
)
59 struct dca_domain
*domain
;
61 domain
= kzalloc(sizeof(*domain
), GFP_NOWAIT
);
65 INIT_LIST_HEAD(&domain
->dca_providers
);
71 static void dca_free_domain(struct dca_domain
*domain
)
73 list_del(&domain
->node
);
77 static int dca_provider_ioat_ver_3_0(struct device
*dev
)
79 struct pci_dev
*pdev
= to_pci_dev(dev
);
81 return ((pdev
->vendor
== PCI_VENDOR_ID_INTEL
) &&
82 ((pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG0
) ||
83 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG1
) ||
84 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG2
) ||
85 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG3
) ||
86 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG4
) ||
87 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG5
) ||
88 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG6
) ||
89 (pdev
->device
== PCI_DEVICE_ID_INTEL_IOAT_TBG7
)));
92 static void unregister_dca_providers(void)
94 struct dca_provider
*dca
, *_dca
;
95 struct list_head unregistered_providers
;
96 struct dca_domain
*domain
;
99 blocking_notifier_call_chain(&dca_provider_chain
,
100 DCA_PROVIDER_REMOVE
, NULL
);
102 INIT_LIST_HEAD(&unregistered_providers
);
104 raw_spin_lock_irqsave(&dca_lock
, flags
);
106 if (list_empty(&dca_domains
)) {
107 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
111 /* at this point only one domain in the list is expected */
112 domain
= list_first_entry(&dca_domains
, struct dca_domain
, node
);
114 list_for_each_entry_safe(dca
, _dca
, &domain
->dca_providers
, node
)
115 list_move(&dca
->node
, &unregistered_providers
);
117 dca_free_domain(domain
);
119 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
121 list_for_each_entry_safe(dca
, _dca
, &unregistered_providers
, node
) {
122 dca_sysfs_remove_provider(dca
);
123 list_del(&dca
->node
);
127 static struct dca_domain
*dca_find_domain(struct pci_bus
*rc
)
129 struct dca_domain
*domain
;
131 list_for_each_entry(domain
, &dca_domains
, node
)
132 if (domain
->pci_rc
== rc
)
138 static struct dca_domain
*dca_get_domain(struct device
*dev
)
141 struct dca_domain
*domain
;
143 rc
= dca_pci_rc_from_dev(dev
);
144 domain
= dca_find_domain(rc
);
147 if (dca_provider_ioat_ver_3_0(dev
) && !list_empty(&dca_domains
))
148 dca_providers_blocked
= 1;
154 static struct dca_provider
*dca_find_provider_by_dev(struct device
*dev
)
156 struct dca_provider
*dca
;
158 struct dca_domain
*domain
;
161 rc
= dca_pci_rc_from_dev(dev
);
162 domain
= dca_find_domain(rc
);
166 if (!list_empty(&dca_domains
))
167 domain
= list_first_entry(&dca_domains
,
174 list_for_each_entry(dca
, &domain
->dca_providers
, node
)
175 if ((!dev
) || (dca
->ops
->dev_managed(dca
, dev
)))
182 * dca_add_requester - add a dca client to the list
183 * @dev - the device that wants dca service
185 int dca_add_requester(struct device
*dev
)
187 struct dca_provider
*dca
;
188 int err
, slot
= -ENODEV
;
190 struct pci_bus
*pci_rc
;
191 struct dca_domain
*domain
;
196 raw_spin_lock_irqsave(&dca_lock
, flags
);
198 /* check if the requester has not been added already */
199 dca
= dca_find_provider_by_dev(dev
);
201 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
205 pci_rc
= dca_pci_rc_from_dev(dev
);
206 domain
= dca_find_domain(pci_rc
);
208 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
212 list_for_each_entry(dca
, &domain
->dca_providers
, node
) {
213 slot
= dca
->ops
->add_requester(dca
, dev
);
218 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
223 err
= dca_sysfs_add_req(dca
, dev
, slot
);
225 raw_spin_lock_irqsave(&dca_lock
, flags
);
226 if (dca
== dca_find_provider_by_dev(dev
))
227 dca
->ops
->remove_requester(dca
, dev
);
228 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
234 EXPORT_SYMBOL_GPL(dca_add_requester
);
237 * dca_remove_requester - remove a dca client from the list
238 * @dev - the device that wants dca service
240 int dca_remove_requester(struct device
*dev
)
242 struct dca_provider
*dca
;
249 raw_spin_lock_irqsave(&dca_lock
, flags
);
250 dca
= dca_find_provider_by_dev(dev
);
252 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
255 slot
= dca
->ops
->remove_requester(dca
, dev
);
256 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
261 dca_sysfs_remove_req(dca
, slot
);
265 EXPORT_SYMBOL_GPL(dca_remove_requester
);
268 * dca_common_get_tag - return the dca tag (serves both new and old api)
269 * @dev - the device that wants dca service
270 * @cpu - the cpuid as returned by get_cpu()
272 u8
dca_common_get_tag(struct device
*dev
, int cpu
)
274 struct dca_provider
*dca
;
278 raw_spin_lock_irqsave(&dca_lock
, flags
);
280 dca
= dca_find_provider_by_dev(dev
);
282 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
285 tag
= dca
->ops
->get_tag(dca
, dev
, cpu
);
287 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
292 * dca3_get_tag - return the dca tag to the requester device
293 * for the given cpu (new api)
294 * @dev - the device that wants dca service
295 * @cpu - the cpuid as returned by get_cpu()
297 u8
dca3_get_tag(struct device
*dev
, int cpu
)
302 return dca_common_get_tag(dev
, cpu
);
304 EXPORT_SYMBOL_GPL(dca3_get_tag
);
307 * dca_get_tag - return the dca tag for the given cpu (old api)
308 * @cpu - the cpuid as returned by get_cpu()
310 u8
dca_get_tag(int cpu
)
312 struct device
*dev
= NULL
;
314 return dca_common_get_tag(dev
, cpu
);
316 EXPORT_SYMBOL_GPL(dca_get_tag
);
319 * alloc_dca_provider - get data struct for describing a dca provider
320 * @ops - pointer to struct of dca operation function pointers
321 * @priv_size - size of extra mem to be added for provider's needs
323 struct dca_provider
*alloc_dca_provider(struct dca_ops
*ops
, int priv_size
)
325 struct dca_provider
*dca
;
328 alloc_size
= (sizeof(*dca
) + priv_size
);
329 dca
= kzalloc(alloc_size
, GFP_KERNEL
);
336 EXPORT_SYMBOL_GPL(alloc_dca_provider
);
339 * free_dca_provider - release the dca provider data struct
340 * @ops - pointer to struct of dca operation function pointers
341 * @priv_size - size of extra mem to be added for provider's needs
343 void free_dca_provider(struct dca_provider
*dca
)
347 EXPORT_SYMBOL_GPL(free_dca_provider
);
350 * register_dca_provider - register a dca provider
351 * @dca - struct created by alloc_dca_provider()
352 * @dev - device providing dca services
354 int register_dca_provider(struct dca_provider
*dca
, struct device
*dev
)
358 struct dca_domain
*domain
, *newdomain
= NULL
;
360 raw_spin_lock_irqsave(&dca_lock
, flags
);
361 if (dca_providers_blocked
) {
362 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
365 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
367 err
= dca_sysfs_add_provider(dca
, dev
);
371 raw_spin_lock_irqsave(&dca_lock
, flags
);
372 domain
= dca_get_domain(dev
);
376 if (dca_providers_blocked
) {
377 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
378 dca_sysfs_remove_provider(dca
);
379 unregister_dca_providers();
383 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
384 rc
= dca_pci_rc_from_dev(dev
);
385 newdomain
= dca_allocate_domain(rc
);
388 raw_spin_lock_irqsave(&dca_lock
, flags
);
389 /* Recheck, we might have raced after dropping the lock */
390 domain
= dca_get_domain(dev
);
394 list_add(&domain
->node
, &dca_domains
);
397 list_add(&dca
->node
, &domain
->dca_providers
);
398 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
400 blocking_notifier_call_chain(&dca_provider_chain
,
401 DCA_PROVIDER_ADD
, NULL
);
405 EXPORT_SYMBOL_GPL(register_dca_provider
);
408 * unregister_dca_provider - remove a dca provider
409 * @dca - struct created by alloc_dca_provider()
411 void unregister_dca_provider(struct dca_provider
*dca
, struct device
*dev
)
414 struct pci_bus
*pci_rc
;
415 struct dca_domain
*domain
;
417 blocking_notifier_call_chain(&dca_provider_chain
,
418 DCA_PROVIDER_REMOVE
, NULL
);
420 raw_spin_lock_irqsave(&dca_lock
, flags
);
422 list_del(&dca
->node
);
424 pci_rc
= dca_pci_rc_from_dev(dev
);
425 domain
= dca_find_domain(pci_rc
);
426 if (list_empty(&domain
->dca_providers
))
427 dca_free_domain(domain
);
429 raw_spin_unlock_irqrestore(&dca_lock
, flags
);
431 dca_sysfs_remove_provider(dca
);
433 EXPORT_SYMBOL_GPL(unregister_dca_provider
);
436 * dca_register_notify - register a client's notifier callback
438 void dca_register_notify(struct notifier_block
*nb
)
440 blocking_notifier_chain_register(&dca_provider_chain
, nb
);
442 EXPORT_SYMBOL_GPL(dca_register_notify
);
445 * dca_unregister_notify - remove a client's notifier callback
447 void dca_unregister_notify(struct notifier_block
*nb
)
449 blocking_notifier_chain_unregister(&dca_provider_chain
, nb
);
451 EXPORT_SYMBOL_GPL(dca_unregister_notify
);
453 static int __init
dca_init(void)
455 pr_info("dca service started, version %s\n", DCA_VERSION
);
456 return dca_sysfs_init();
459 static void __exit
dca_exit(void)
464 arch_initcall(dca_init
);
465 module_exit(dca_exit
);