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_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 spin_lock_irqsave(&dca_lock, flags);
106 if (list_empty(&dca_domains)) {
107 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_del(&dca->node);
116 list_add(&dca->node, &unregistered_providers);
119 dca_free_domain(domain);
121 spin_unlock_irqrestore(&dca_lock, flags);
123 list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
124 dca_sysfs_remove_provider(dca);
125 list_del(&dca->node);
129 static struct dca_domain *dca_find_domain(struct pci_bus *rc)
131 struct dca_domain *domain;
133 list_for_each_entry(domain, &dca_domains, node)
134 if (domain->pci_rc == rc)
140 static struct dca_domain *dca_get_domain(struct device *dev)
143 struct dca_domain *domain;
145 rc = dca_pci_rc_from_dev(dev);
146 domain = dca_find_domain(rc);
149 if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains)) {
150 dca_providers_blocked = 1;
152 domain = dca_allocate_domain(rc);
154 list_add(&domain->node, &dca_domains);
161 static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
163 struct dca_provider *dca;
165 struct dca_domain *domain;
168 rc = dca_pci_rc_from_dev(dev);
169 domain = dca_find_domain(rc);
173 if (!list_empty(&dca_domains))
174 domain = list_first_entry(&dca_domains,
181 list_for_each_entry(dca, &domain->dca_providers, node)
182 if ((!dev) || (dca->ops->dev_managed(dca, dev)))
189 * dca_add_requester - add a dca client to the list
190 * @dev - the device that wants dca service
192 int dca_add_requester(struct device *dev)
194 struct dca_provider *dca;
195 int err, slot = -ENODEV;
197 struct pci_bus *pci_rc;
198 struct dca_domain *domain;
203 spin_lock_irqsave(&dca_lock, flags);
205 /* check if the requester has not been added already */
206 dca = dca_find_provider_by_dev(dev);
208 spin_unlock_irqrestore(&dca_lock, flags);
212 pci_rc = dca_pci_rc_from_dev(dev);
213 domain = dca_find_domain(pci_rc);
215 spin_unlock_irqrestore(&dca_lock, flags);
219 list_for_each_entry(dca, &domain->dca_providers, node) {
220 slot = dca->ops->add_requester(dca, dev);
225 spin_unlock_irqrestore(&dca_lock, flags);
230 err = dca_sysfs_add_req(dca, dev, slot);
232 spin_lock_irqsave(&dca_lock, flags);
233 if (dca == dca_find_provider_by_dev(dev))
234 dca->ops->remove_requester(dca, dev);
235 spin_unlock_irqrestore(&dca_lock, flags);
241 EXPORT_SYMBOL_GPL(dca_add_requester);
244 * dca_remove_requester - remove a dca client from the list
245 * @dev - the device that wants dca service
247 int dca_remove_requester(struct device *dev)
249 struct dca_provider *dca;
256 spin_lock_irqsave(&dca_lock, flags);
257 dca = dca_find_provider_by_dev(dev);
259 spin_unlock_irqrestore(&dca_lock, flags);
262 slot = dca->ops->remove_requester(dca, dev);
263 spin_unlock_irqrestore(&dca_lock, flags);
268 dca_sysfs_remove_req(dca, slot);
272 EXPORT_SYMBOL_GPL(dca_remove_requester);
275 * dca_common_get_tag - return the dca tag (serves both new and old api)
276 * @dev - the device that wants dca service
277 * @cpu - the cpuid as returned by get_cpu()
279 u8 dca_common_get_tag(struct device *dev, int cpu)
281 struct dca_provider *dca;
285 spin_lock_irqsave(&dca_lock, flags);
287 dca = dca_find_provider_by_dev(dev);
289 spin_unlock_irqrestore(&dca_lock, flags);
292 tag = dca->ops->get_tag(dca, dev, cpu);
294 spin_unlock_irqrestore(&dca_lock, flags);
299 * dca3_get_tag - return the dca tag to the requester device
300 * for the given cpu (new api)
301 * @dev - the device that wants dca service
302 * @cpu - the cpuid as returned by get_cpu()
304 u8 dca3_get_tag(struct device *dev, int cpu)
309 return dca_common_get_tag(dev, cpu);
311 EXPORT_SYMBOL_GPL(dca3_get_tag);
314 * dca_get_tag - return the dca tag for the given cpu (old api)
315 * @cpu - the cpuid as returned by get_cpu()
317 u8 dca_get_tag(int cpu)
319 struct device *dev = NULL;
321 return dca_common_get_tag(dev, cpu);
323 EXPORT_SYMBOL_GPL(dca_get_tag);
326 * alloc_dca_provider - get data struct for describing a dca provider
327 * @ops - pointer to struct of dca operation function pointers
328 * @priv_size - size of extra mem to be added for provider's needs
330 struct dca_provider *alloc_dca_provider(struct dca_ops *ops, int priv_size)
332 struct dca_provider *dca;
335 alloc_size = (sizeof(*dca) + priv_size);
336 dca = kzalloc(alloc_size, GFP_KERNEL);
343 EXPORT_SYMBOL_GPL(alloc_dca_provider);
346 * free_dca_provider - release the dca provider data struct
347 * @ops - pointer to struct of dca operation function pointers
348 * @priv_size - size of extra mem to be added for provider's needs
350 void free_dca_provider(struct dca_provider *dca)
354 EXPORT_SYMBOL_GPL(free_dca_provider);
357 * register_dca_provider - register a dca provider
358 * @dca - struct created by alloc_dca_provider()
359 * @dev - device providing dca services
361 int register_dca_provider(struct dca_provider *dca, struct device *dev)
365 struct dca_domain *domain;
367 spin_lock_irqsave(&dca_lock, flags);
368 if (dca_providers_blocked) {
369 spin_unlock_irqrestore(&dca_lock, flags);
372 spin_unlock_irqrestore(&dca_lock, flags);
374 err = dca_sysfs_add_provider(dca, dev);
378 spin_lock_irqsave(&dca_lock, flags);
379 domain = dca_get_domain(dev);
381 if (dca_providers_blocked) {
382 spin_unlock_irqrestore(&dca_lock, flags);
383 dca_sysfs_remove_provider(dca);
384 unregister_dca_providers();
386 spin_unlock_irqrestore(&dca_lock, flags);
390 list_add(&dca->node, &domain->dca_providers);
391 spin_unlock_irqrestore(&dca_lock, flags);
393 blocking_notifier_call_chain(&dca_provider_chain,
394 DCA_PROVIDER_ADD, NULL);
397 EXPORT_SYMBOL_GPL(register_dca_provider);
400 * unregister_dca_provider - remove a dca provider
401 * @dca - struct created by alloc_dca_provider()
403 void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
406 struct pci_bus *pci_rc;
407 struct dca_domain *domain;
409 blocking_notifier_call_chain(&dca_provider_chain,
410 DCA_PROVIDER_REMOVE, NULL);
412 spin_lock_irqsave(&dca_lock, flags);
414 list_del(&dca->node);
416 pci_rc = dca_pci_rc_from_dev(dev);
417 domain = dca_find_domain(pci_rc);
418 if (list_empty(&domain->dca_providers))
419 dca_free_domain(domain);
421 spin_unlock_irqrestore(&dca_lock, flags);
423 dca_sysfs_remove_provider(dca);
425 EXPORT_SYMBOL_GPL(unregister_dca_provider);
428 * dca_register_notify - register a client's notifier callback
430 void dca_register_notify(struct notifier_block *nb)
432 blocking_notifier_chain_register(&dca_provider_chain, nb);
434 EXPORT_SYMBOL_GPL(dca_register_notify);
437 * dca_unregister_notify - remove a client's notifier callback
439 void dca_unregister_notify(struct notifier_block *nb)
441 blocking_notifier_chain_unregister(&dca_provider_chain, nb);
443 EXPORT_SYMBOL_GPL(dca_unregister_notify);
445 static int __init dca_init(void)
447 pr_info("dca service started, version %s\n", DCA_VERSION);
448 return dca_sysfs_init();
451 static void __exit dca_exit(void)
456 arch_initcall(dca_init);
457 module_exit(dca_exit);