Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
[pandora-kernel.git] / arch / x86 / pci / xen.c
1 /*
2  * Xen PCI Frontend Stub - puts some "dummy" functions in to the Linux
3  *                         x86 PCI core to support the Xen PCI Frontend
4  *
5  *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
6  */
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/pci.h>
10 #include <linux/acpi.h>
11
12 #include <linux/io.h>
13 #include <asm/io_apic.h>
14 #include <asm/pci_x86.h>
15
16 #include <asm/xen/hypervisor.h>
17
18 #include <xen/features.h>
19 #include <xen/events.h>
20 #include <asm/xen/pci.h>
21
22 #ifdef CONFIG_ACPI
23 static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
24                                  int trigger, int polarity)
25 {
26         int rc, irq;
27         struct physdev_map_pirq map_irq;
28         int shareable = 0;
29         char *name;
30
31         if (!xen_hvm_domain())
32                 return -1;
33
34         map_irq.domid = DOMID_SELF;
35         map_irq.type = MAP_PIRQ_TYPE_GSI;
36         map_irq.index = gsi;
37         map_irq.pirq = -1;
38
39         rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
40         if (rc) {
41                 printk(KERN_WARNING "xen map irq failed %d\n", rc);
42                 return -1;
43         }
44
45         if (trigger == ACPI_EDGE_SENSITIVE) {
46                 shareable = 0;
47                 name = "ioapic-edge";
48         } else {
49                 shareable = 1;
50                 name = "ioapic-level";
51         }
52
53         irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
54
55         printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
56
57         return irq;
58 }
59 #endif
60
61 #if defined(CONFIG_PCI_MSI)
62 #include <linux/msi.h>
63 #include <asm/msidef.h>
64
65 struct xen_pci_frontend_ops *xen_pci_frontend;
66 EXPORT_SYMBOL_GPL(xen_pci_frontend);
67
68 #define XEN_PIRQ_MSI_DATA  (MSI_DATA_TRIGGER_EDGE | \
69                 MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0))
70
71 static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
72                 struct msi_msg *msg)
73 {
74         /* We set vector == 0 to tell the hypervisor we don't care about it,
75          * but we want a pirq setup instead.
76          * We use the dest_id field to pass the pirq that we want. */
77         msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq);
78         msg->address_lo =
79                 MSI_ADDR_BASE_LO |
80                 MSI_ADDR_DEST_MODE_PHYSICAL |
81                 MSI_ADDR_REDIRECTION_CPU |
82                 MSI_ADDR_DEST_ID(pirq);
83
84         msg->data = XEN_PIRQ_MSI_DATA;
85 }
86
87 static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
88 {
89         int irq, pirq;
90         struct msi_desc *msidesc;
91         struct msi_msg msg;
92
93         list_for_each_entry(msidesc, &dev->msi_list, list) {
94                 __read_msi_msg(msidesc, &msg);
95                 pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) |
96                         ((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff);
97                 if (msg.data != XEN_PIRQ_MSI_DATA ||
98                     xen_irq_from_pirq(pirq) < 0) {
99                         pirq = xen_allocate_pirq_msi(dev, msidesc);
100                         if (pirq < 0)
101                                 goto error;
102                         xen_msi_compose_msg(dev, pirq, &msg);
103                         __write_msi_msg(msidesc, &msg);
104                         dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq);
105                 } else {
106                         dev_dbg(&dev->dev,
107                                 "xen: msi already bound to pirq=%d\n", pirq);
108                 }
109                 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq, 0,
110                                                (type == PCI_CAP_ID_MSIX) ?
111                                                "msi-x" : "msi",
112                                                DOMID_SELF);
113                 if (irq < 0)
114                         goto error;
115                 dev_dbg(&dev->dev,
116                         "xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
117         }
118         return 0;
119
120 error:
121         dev_err(&dev->dev,
122                 "Xen PCI frontend has not registered MSI/MSI-X support!\n");
123         return -ENODEV;
124 }
125
126 /*
127  * For MSI interrupts we have to use drivers/xen/event.s functions to
128  * allocate an irq_desc and setup the right */
129
130
131 static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
132 {
133         int irq, ret, i;
134         struct msi_desc *msidesc;
135         int *v;
136
137         v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
138         if (!v)
139                 return -ENOMEM;
140
141         if (type == PCI_CAP_ID_MSIX)
142                 ret = xen_pci_frontend_enable_msix(dev, v, nvec);
143         else
144                 ret = xen_pci_frontend_enable_msi(dev, v);
145         if (ret)
146                 goto error;
147         i = 0;
148         list_for_each_entry(msidesc, &dev->msi_list, list) {
149                 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], 0,
150                                                (type == PCI_CAP_ID_MSIX) ?
151                                                "pcifront-msi-x" :
152                                                "pcifront-msi",
153                                                 DOMID_SELF);
154                 if (irq < 0)
155                         goto free;
156                 i++;
157         }
158         kfree(v);
159         return 0;
160
161 error:
162         dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n");
163 free:
164         kfree(v);
165         return ret;
166 }
167
168 static void xen_teardown_msi_irqs(struct pci_dev *dev)
169 {
170         struct msi_desc *msidesc;
171
172         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
173         if (msidesc->msi_attrib.is_msix)
174                 xen_pci_frontend_disable_msix(dev);
175         else
176                 xen_pci_frontend_disable_msi(dev);
177
178         /* Free the IRQ's and the msidesc using the generic code. */
179         default_teardown_msi_irqs(dev);
180 }
181
182 static void xen_teardown_msi_irq(unsigned int irq)
183 {
184         xen_destroy_irq(irq);
185 }
186
187 #ifdef CONFIG_XEN_DOM0
188 static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
189 {
190         int ret = 0;
191         struct msi_desc *msidesc;
192
193         list_for_each_entry(msidesc, &dev->msi_list, list) {
194                 struct physdev_map_pirq map_irq;
195                 domid_t domid;
196
197                 domid = ret = xen_find_device_domain_owner(dev);
198                 /* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED,
199                  * hence check ret value for < 0. */
200                 if (ret < 0)
201                         domid = DOMID_SELF;
202
203                 memset(&map_irq, 0, sizeof(map_irq));
204                 map_irq.domid = domid;
205                 map_irq.type = MAP_PIRQ_TYPE_MSI;
206                 map_irq.index = -1;
207                 map_irq.pirq = -1;
208                 map_irq.bus = dev->bus->number;
209                 map_irq.devfn = dev->devfn;
210
211                 if (type == PCI_CAP_ID_MSIX) {
212                         int pos;
213                         u32 table_offset, bir;
214
215                         pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
216
217                         pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
218                                               &table_offset);
219                         bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
220
221                         map_irq.table_base = pci_resource_start(dev, bir);
222                         map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
223                 }
224
225                 ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
226                 if (ret) {
227                         dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
228                                  ret, domid);
229                         goto out;
230                 }
231
232                 ret = xen_bind_pirq_msi_to_irq(dev, msidesc,
233                                                map_irq.pirq, map_irq.index,
234                                                (type == PCI_CAP_ID_MSIX) ?
235                                                "msi-x" : "msi",
236                                                 domid);
237                 if (ret < 0)
238                         goto out;
239         }
240         ret = 0;
241 out:
242         return ret;
243 }
244 #endif
245 #endif
246
247 static int xen_pcifront_enable_irq(struct pci_dev *dev)
248 {
249         int rc;
250         int share = 1;
251         int pirq;
252         u8 gsi;
253
254         rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
255         if (rc < 0) {
256                 dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
257                          rc);
258                 return rc;
259         }
260
261         rc = xen_allocate_pirq_gsi(gsi);
262         if (rc < 0) {
263                 dev_warn(&dev->dev, "Xen PCI: failed to allocate a PIRQ for GSI%d: %d\n",
264                          gsi, rc);
265                 return rc;
266         }
267         pirq = rc;
268
269         if (gsi < NR_IRQS_LEGACY)
270                 share = 0;
271
272         rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
273         if (rc < 0) {
274                 dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n",
275                          gsi, pirq, rc);
276                 return rc;
277         }
278
279         dev->irq = rc;
280         dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq);
281         return 0;
282 }
283
284 int __init pci_xen_init(void)
285 {
286         if (!xen_pv_domain() || xen_initial_domain())
287                 return -ENODEV;
288
289         printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
290
291         pcibios_set_cache_line_size();
292
293         pcibios_enable_irq = xen_pcifront_enable_irq;
294         pcibios_disable_irq = NULL;
295
296 #ifdef CONFIG_ACPI
297         /* Keep ACPI out of the picture */
298         acpi_noirq = 1;
299 #endif
300
301 #ifdef CONFIG_PCI_MSI
302         x86_msi.setup_msi_irqs = xen_setup_msi_irqs;
303         x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
304         x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
305 #endif
306         return 0;
307 }
308
309 int __init pci_xen_hvm_init(void)
310 {
311         if (!xen_feature(XENFEAT_hvm_pirqs))
312                 return 0;
313
314 #ifdef CONFIG_ACPI
315         /*
316          * We don't want to change the actual ACPI delivery model,
317          * just how GSIs get registered.
318          */
319         __acpi_register_gsi = acpi_register_gsi_xen_hvm;
320 #endif
321
322 #ifdef CONFIG_PCI_MSI
323         x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
324         x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
325 #endif
326         return 0;
327 }
328
329 #ifdef CONFIG_XEN_DOM0
330 static int xen_register_pirq(u32 gsi, int triggering)
331 {
332         int rc, pirq, irq = -1;
333         struct physdev_map_pirq map_irq;
334         int shareable = 0;
335         char *name;
336
337         if (!xen_pv_domain())
338                 return -1;
339
340         if (triggering == ACPI_EDGE_SENSITIVE) {
341                 shareable = 0;
342                 name = "ioapic-edge";
343         } else {
344                 shareable = 1;
345                 name = "ioapic-level";
346         }
347
348         pirq = xen_allocate_pirq_gsi(gsi);
349         if (pirq < 0)
350                 goto out;
351
352         irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
353         if (irq < 0)
354                 goto out;
355
356         printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d\n", pirq, irq);
357
358         map_irq.domid = DOMID_SELF;
359         map_irq.type = MAP_PIRQ_TYPE_GSI;
360         map_irq.index = gsi;
361         map_irq.pirq = pirq;
362
363         rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
364         if (rc) {
365                 printk(KERN_WARNING "xen map irq failed %d\n", rc);
366                 return -1;
367         }
368
369 out:
370         return irq;
371 }
372
373 static int xen_register_gsi(u32 gsi, int triggering, int polarity)
374 {
375         int rc, irq;
376         struct physdev_setup_gsi setup_gsi;
377
378         if (!xen_pv_domain())
379                 return -1;
380
381         printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
382                         gsi, triggering, polarity);
383
384         irq = xen_register_pirq(gsi, triggering);
385
386         setup_gsi.gsi = gsi;
387         setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
388         setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
389
390         rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
391         if (rc == -EEXIST)
392                 printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
393         else if (rc) {
394                 printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
395                                 gsi, rc);
396         }
397
398         return irq;
399 }
400
401 static __init void xen_setup_acpi_sci(void)
402 {
403         int rc;
404         int trigger, polarity;
405         int gsi = acpi_sci_override_gsi;
406
407         if (!gsi)
408                 return;
409
410         rc = acpi_get_override_irq(gsi, &trigger, &polarity);
411         if (rc) {
412                 printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi"
413                                 " sci, rc=%d\n", rc);
414                 return;
415         }
416         trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
417         polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
418         
419         printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
420                         "polarity=%d\n", gsi, trigger, polarity);
421
422         gsi = xen_register_gsi(gsi, trigger, polarity);
423         printk(KERN_INFO "xen: acpi sci %d\n", gsi);
424
425         return;
426 }
427
428 static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
429                                  int trigger, int polarity)
430 {
431         return xen_register_gsi(gsi, trigger, polarity);
432 }
433
434 static int __init pci_xen_initial_domain(void)
435 {
436 #ifdef CONFIG_PCI_MSI
437         x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
438         x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
439 #endif
440         xen_setup_acpi_sci();
441         __acpi_register_gsi = acpi_register_gsi_xen;
442
443         return 0;
444 }
445
446 void __init xen_setup_pirqs(void)
447 {
448         int pirq, irq;
449
450         pci_xen_initial_domain();
451
452         if (0 == nr_ioapics) {
453                 for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
454                         pirq = xen_allocate_pirq_gsi(irq);
455                         if (WARN(pirq < 0,
456                                  "Could not allocate PIRQ for legacy interrupt\n"))
457                                 break;
458                         irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
459                 }
460                 return;
461         }
462
463         /* Pre-allocate legacy irqs */
464         for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
465                 int trigger, polarity;
466
467                 if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
468                         continue;
469
470                 xen_register_pirq(irq,
471                         trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
472         }
473 }
474 #endif
475
476 #ifdef CONFIG_XEN_DOM0
477 struct xen_device_domain_owner {
478         domid_t domain;
479         struct pci_dev *dev;
480         struct list_head list;
481 };
482
483 static DEFINE_SPINLOCK(dev_domain_list_spinlock);
484 static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list);
485
486 static struct xen_device_domain_owner *find_device(struct pci_dev *dev)
487 {
488         struct xen_device_domain_owner *owner;
489
490         list_for_each_entry(owner, &dev_domain_list, list) {
491                 if (owner->dev == dev)
492                         return owner;
493         }
494         return NULL;
495 }
496
497 int xen_find_device_domain_owner(struct pci_dev *dev)
498 {
499         struct xen_device_domain_owner *owner;
500         int domain = -ENODEV;
501
502         spin_lock(&dev_domain_list_spinlock);
503         owner = find_device(dev);
504         if (owner)
505                 domain = owner->domain;
506         spin_unlock(&dev_domain_list_spinlock);
507         return domain;
508 }
509 EXPORT_SYMBOL_GPL(xen_find_device_domain_owner);
510
511 int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain)
512 {
513         struct xen_device_domain_owner *owner;
514
515         owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL);
516         if (!owner)
517                 return -ENODEV;
518
519         spin_lock(&dev_domain_list_spinlock);
520         if (find_device(dev)) {
521                 spin_unlock(&dev_domain_list_spinlock);
522                 kfree(owner);
523                 return -EEXIST;
524         }
525         owner->domain = domain;
526         owner->dev = dev;
527         list_add_tail(&owner->list, &dev_domain_list);
528         spin_unlock(&dev_domain_list_spinlock);
529         return 0;
530 }
531 EXPORT_SYMBOL_GPL(xen_register_device_domain_owner);
532
533 int xen_unregister_device_domain_owner(struct pci_dev *dev)
534 {
535         struct xen_device_domain_owner *owner;
536
537         spin_lock(&dev_domain_list_spinlock);
538         owner = find_device(dev);
539         if (!owner) {
540                 spin_unlock(&dev_domain_list_spinlock);
541                 return -ENODEV;
542         }
543         list_del(&owner->list);
544         spin_unlock(&dev_domain_list_spinlock);
545         kfree(owner);
546         return 0;
547 }
548 EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner);
549 #endif