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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Xen PCI - handle PCI (INTx) and MSI infrastructure calls for PV, HVM and
  4 * initial domain support. We also handle the DSDT _PRT callbacks for GSI's
  5 * used in HVM and initial domain mode (PV does not parse ACPI, so it has no
  6 * concept of GSIs). Under PV we hook under the pnbbios API for IRQs and
  7 * 0xcf8 PCI configuration read/write.
  8 *
  9 *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
 10 *           Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
 11 *           Stefano Stabellini <stefano.stabellini@eu.citrix.com>
 12 */
 13#include <linux/export.h>
 14#include <linux/init.h>
 15#include <linux/pci.h>
 16#include <linux/acpi.h>
 17
 18#include <linux/io.h>
 19#include <asm/io_apic.h>
 20#include <asm/pci_x86.h>
 21
 22#include <asm/xen/hypervisor.h>
 23
 24#include <xen/features.h>
 25#include <xen/events.h>
 26#include <xen/pci.h>
 27#include <asm/xen/pci.h>
 28#include <asm/xen/cpuid.h>
 29#include <asm/apic.h>
 30#include <asm/acpi.h>
 31#include <asm/i8259.h>
 32
 33static int xen_pcifront_enable_irq(struct pci_dev *dev)
 34{
 35	int rc;
 36	int share = 1;
 37	int pirq;
 38	u8 gsi;
 39
 40	rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
 41	if (rc < 0) {
 42		dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
 43			 rc);
 44		return rc;
 45	}
 46	/* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/
 47	pirq = gsi;
 48
 49	if (gsi < nr_legacy_irqs())
 50		share = 0;
 51
 52	rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
 53	if (rc < 0) {
 54		dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n",
 55			 gsi, pirq, rc);
 56		return rc;
 57	}
 58
 59	dev->irq = rc;
 60	dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq);
 61	return 0;
 62}
 63
 64#ifdef CONFIG_ACPI
 65static int xen_register_pirq(u32 gsi, int triggering, bool set_pirq)
 
 66{
 67	int rc, pirq = -1, irq;
 68	struct physdev_map_pirq map_irq;
 69	int shareable = 0;
 70	char *name;
 71
 72	irq = xen_irq_from_gsi(gsi);
 73	if (irq > 0)
 74		return irq;
 75
 76	if (set_pirq)
 77		pirq = gsi;
 78
 79	map_irq.domid = DOMID_SELF;
 80	map_irq.type = MAP_PIRQ_TYPE_GSI;
 81	map_irq.index = gsi;
 82	map_irq.pirq = pirq;
 83
 84	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
 85	if (rc) {
 86		printk(KERN_WARNING "xen map irq failed %d\n", rc);
 87		return -1;
 88	}
 89
 90	if (triggering == ACPI_EDGE_SENSITIVE) {
 91		shareable = 0;
 92		name = "ioapic-edge";
 93	} else {
 94		shareable = 1;
 95		name = "ioapic-level";
 96	}
 97
 
 
 
 98	irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
 99	if (irq < 0)
100		goto out;
101
102	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi);
103out:
104	return irq;
105}
106
107static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
108				     int trigger, int polarity)
109{
110	if (!xen_hvm_domain())
111		return -1;
112
113	return xen_register_pirq(gsi, trigger,
114				 false /* no mapping of GSI to PIRQ */);
115}
116
117#ifdef CONFIG_XEN_PV_DOM0
118static int xen_register_gsi(u32 gsi, int triggering, int polarity)
119{
120	int rc, irq;
121	struct physdev_setup_gsi setup_gsi;
122
123	if (!xen_pv_domain())
124		return -1;
125
126	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
127			gsi, triggering, polarity);
128
129	irq = xen_register_pirq(gsi, triggering, true);
130
131	setup_gsi.gsi = gsi;
132	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
133	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
134
135	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
136	if (rc == -EEXIST)
137		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
138	else if (rc) {
139		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
140				gsi, rc);
141	}
142
143	return irq;
144}
145
146static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
147				 int trigger, int polarity)
148{
149	return xen_register_gsi(gsi, trigger, polarity);
150}
151#endif
152#endif
153
154#if defined(CONFIG_PCI_MSI)
155#include <linux/msi.h>
 
156
157struct xen_pci_frontend_ops *xen_pci_frontend;
158EXPORT_SYMBOL_GPL(xen_pci_frontend);
159
160struct xen_msi_ops {
161	int (*setup_msi_irqs)(struct pci_dev *dev, int nvec, int type);
162	void (*teardown_msi_irqs)(struct pci_dev *dev);
163};
164
165static struct xen_msi_ops xen_msi_ops __ro_after_init;
166
167static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
168{
169	int irq, ret, i;
170	struct msi_desc *msidesc;
171	int *v;
172
173	if (type == PCI_CAP_ID_MSI && nvec > 1)
174		return 1;
175
176	v = kcalloc(max(1, nvec), sizeof(int), GFP_KERNEL);
177	if (!v)
178		return -ENOMEM;
179
180	if (type == PCI_CAP_ID_MSIX)
181		ret = xen_pci_frontend_enable_msix(dev, v, nvec);
182	else
183		ret = xen_pci_frontend_enable_msi(dev, v);
184	if (ret)
185		goto error;
186	i = 0;
187	msi_for_each_desc(msidesc, &dev->dev, MSI_DESC_NOTASSOCIATED) {
188		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i],
189					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
190					       (type == PCI_CAP_ID_MSIX) ?
191					       "pcifront-msi-x" :
192					       "pcifront-msi",
193						DOMID_SELF);
194		if (irq < 0) {
195			ret = irq;
196			goto free;
197		}
198		i++;
199	}
200	kfree(v);
201	return msi_device_populate_sysfs(&dev->dev);
202
203error:
204	if (ret == -ENOSYS)
205		dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n");
206	else if (ret)
207		dev_err(&dev->dev, "Xen PCI frontend error: %d!\n", ret);
208free:
209	kfree(v);
210	return ret;
211}
212
 
 
 
213static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
214		struct msi_msg *msg)
215{
216	/*
217	 * We set vector == 0 to tell the hypervisor we don't care about
218	 * it, but we want a pirq setup instead.  We use the dest_id fields
219	 * to pass the pirq that we want.
220	 */
221	memset(msg, 0, sizeof(*msg));
222	msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
223	msg->arch_addr_hi.destid_8_31 = pirq >> 8;
224	msg->arch_addr_lo.destid_0_7 = pirq & 0xFF;
225	msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
226	msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_EXTINT;
227}
228
229static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
230{
231	int irq, pirq;
232	struct msi_desc *msidesc;
233	struct msi_msg msg;
234
235	if (type == PCI_CAP_ID_MSI && nvec > 1)
236		return 1;
237
238	msi_for_each_desc(msidesc, &dev->dev, MSI_DESC_NOTASSOCIATED) {
239		pirq = xen_allocate_pirq_msi(dev, msidesc);
240		if (pirq < 0) {
241			irq = -ENODEV;
242			goto error;
 
 
 
 
 
 
 
 
 
 
 
 
243		}
244		xen_msi_compose_msg(dev, pirq, &msg);
245		__pci_write_msi_msg(msidesc, &msg);
246		dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq);
247		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq,
248					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
249					       (type == PCI_CAP_ID_MSIX) ?
250					       "msi-x" : "msi",
251					       DOMID_SELF);
252		if (irq < 0)
253			goto error;
254		dev_dbg(&dev->dev,
255			"xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
256	}
257	return msi_device_populate_sysfs(&dev->dev);
258
259error:
260	dev_err(&dev->dev, "Failed to create MSI%s! ret=%d!\n",
261		type == PCI_CAP_ID_MSI ? "" : "-X", irq);
262	return irq;
263}
264
265#ifdef CONFIG_XEN_PV_DOM0
266static bool __read_mostly pci_seg_supported = true;
267
268static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
269{
270	int ret = 0;
271	struct msi_desc *msidesc;
272
273	msi_for_each_desc(msidesc, &dev->dev, MSI_DESC_NOTASSOCIATED) {
274		struct physdev_map_pirq map_irq;
275		domid_t domid;
276
277		domid = ret = xen_find_device_domain_owner(dev);
278		/* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED,
279		 * hence check ret value for < 0. */
280		if (ret < 0)
281			domid = DOMID_SELF;
282
283		memset(&map_irq, 0, sizeof(map_irq));
284		map_irq.domid = domid;
285		map_irq.type = MAP_PIRQ_TYPE_MSI_SEG;
286		map_irq.index = -1;
287		map_irq.pirq = -1;
288		map_irq.bus = dev->bus->number |
289			      (pci_domain_nr(dev->bus) << 16);
290		map_irq.devfn = dev->devfn;
291
292		if (type == PCI_CAP_ID_MSI && nvec > 1) {
293			map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI;
294			map_irq.entry_nr = nvec;
295		} else if (type == PCI_CAP_ID_MSIX) {
296			int pos;
297			unsigned long flags;
298			u32 table_offset, bir;
299
300			pos = dev->msix_cap;
301			pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
302					      &table_offset);
303			bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
304			flags = pci_resource_flags(dev, bir);
305			if (!flags || (flags & IORESOURCE_UNSET))
306				return -EINVAL;
307
308			map_irq.table_base = pci_resource_start(dev, bir);
309			map_irq.entry_nr = msidesc->msi_index;
310		}
311
312		ret = -EINVAL;
313		if (pci_seg_supported)
314			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
315						    &map_irq);
316		if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) {
317			/*
318			 * If MAP_PIRQ_TYPE_MULTI_MSI is not available
319			 * there's nothing else we can do in this case.
320			 * Just set ret > 0 so driver can retry with
321			 * single MSI.
322			 */
323			ret = 1;
324			goto out;
325		}
326		if (ret == -EINVAL && !pci_domain_nr(dev->bus)) {
327			map_irq.type = MAP_PIRQ_TYPE_MSI;
328			map_irq.index = -1;
329			map_irq.pirq = -1;
330			map_irq.bus = dev->bus->number;
331			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
332						    &map_irq);
333			if (ret != -EINVAL)
334				pci_seg_supported = false;
335		}
336		if (ret) {
337			dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
338				 ret, domid);
339			goto out;
340		}
341
342		ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq,
343		                               (type == PCI_CAP_ID_MSI) ? nvec : 1,
344		                               (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi",
345		                               domid);
346		if (ret < 0)
347			goto out;
348	}
349	ret = msi_device_populate_sysfs(&dev->dev);
350out:
351	return ret;
352}
353
354bool xen_initdom_restore_msi(struct pci_dev *dev)
355{
356	int ret = 0;
357
358	if (!xen_initial_domain())
359		return true;
360
361	if (pci_seg_supported) {
362		struct physdev_pci_device restore_ext;
363
364		restore_ext.seg = pci_domain_nr(dev->bus);
365		restore_ext.bus = dev->bus->number;
366		restore_ext.devfn = dev->devfn;
367		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext,
368					&restore_ext);
369		if (ret == -ENOSYS)
370			pci_seg_supported = false;
371		WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret);
372	}
373	if (!pci_seg_supported) {
374		struct physdev_restore_msi restore;
375
376		restore.bus = dev->bus->number;
377		restore.devfn = dev->devfn;
378		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore);
379		WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret);
380	}
381	return false;
382}
383#else /* CONFIG_XEN_PV_DOM0 */
384#define xen_initdom_setup_msi_irqs	NULL
385#endif /* !CONFIG_XEN_PV_DOM0 */
386
387static void xen_teardown_msi_irqs(struct pci_dev *dev)
388{
389	struct msi_desc *msidesc;
390	int i;
391
392	msi_for_each_desc(msidesc, &dev->dev, MSI_DESC_ASSOCIATED) {
393		for (i = 0; i < msidesc->nvec_used; i++)
394			xen_destroy_irq(msidesc->irq + i);
395		msidesc->irq = 0;
396	}
397
398	msi_device_destroy_sysfs(&dev->dev);
399}
400
401static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
402{
403	if (dev->msix_enabled)
404		xen_pci_frontend_disable_msix(dev);
405	else
406		xen_pci_frontend_disable_msi(dev);
407
408	xen_teardown_msi_irqs(dev);
409}
410
411static int xen_msi_domain_alloc_irqs(struct irq_domain *domain,
412				     struct device *dev,  int nvec)
413{
414	int type;
415
416	if (WARN_ON_ONCE(!dev_is_pci(dev)))
417		return -EINVAL;
418
419	type = to_pci_dev(dev)->msix_enabled ? PCI_CAP_ID_MSIX : PCI_CAP_ID_MSI;
420
421	return xen_msi_ops.setup_msi_irqs(to_pci_dev(dev), nvec, type);
422}
423
424static void xen_msi_domain_free_irqs(struct irq_domain *domain,
425				     struct device *dev)
426{
427	if (WARN_ON_ONCE(!dev_is_pci(dev)))
428		return;
429
430	xen_msi_ops.teardown_msi_irqs(to_pci_dev(dev));
431}
432
433static struct msi_domain_ops xen_pci_msi_domain_ops = {
434	.domain_alloc_irqs	= xen_msi_domain_alloc_irqs,
435	.domain_free_irqs	= xen_msi_domain_free_irqs,
436};
437
438static struct msi_domain_info xen_pci_msi_domain_info = {
439	.flags			= MSI_FLAG_PCI_MSIX | MSI_FLAG_FREE_MSI_DESCS | MSI_FLAG_DEV_SYSFS,
440	.ops			= &xen_pci_msi_domain_ops,
441};
442
443/*
444 * This irq domain is a blatant violation of the irq domain design, but
445 * distangling XEN into real irq domains is not a job for mere mortals with
446 * limited XENology. But it's the least dangerous way for a mere mortal to
447 * get rid of the arch_*_msi_irqs() hackery in order to store the irq
448 * domain pointer in struct device. This irq domain wrappery allows to do
449 * that without breaking XEN terminally.
450 */
451static __init struct irq_domain *xen_create_pci_msi_domain(void)
452{
453	struct irq_domain *d = NULL;
454	struct fwnode_handle *fn;
455
456	fn = irq_domain_alloc_named_fwnode("XEN-MSI");
457	if (fn)
458		d = msi_create_irq_domain(fn, &xen_pci_msi_domain_info, NULL);
459
460	/* FIXME: No idea how to survive if this fails */
461	BUG_ON(!d);
462
463	return d;
464}
465
466static __init void xen_setup_pci_msi(void)
467{
468	if (xen_pv_domain()) {
469		if (xen_initial_domain())
470			xen_msi_ops.setup_msi_irqs = xen_initdom_setup_msi_irqs;
471		else
472			xen_msi_ops.setup_msi_irqs = xen_setup_msi_irqs;
473		xen_msi_ops.teardown_msi_irqs = xen_pv_teardown_msi_irqs;
474	} else if (xen_hvm_domain()) {
475		xen_msi_ops.setup_msi_irqs = xen_hvm_setup_msi_irqs;
476		xen_msi_ops.teardown_msi_irqs = xen_teardown_msi_irqs;
477	} else {
478		WARN_ON_ONCE(1);
479		return;
480	}
481
482	/*
483	 * Override the PCI/MSI irq domain init function. No point
484	 * in allocating the native domain and never use it.
485	 */
486	x86_init.irqs.create_pci_msi_domain = xen_create_pci_msi_domain;
487	/*
488	 * With XEN PIRQ/Eventchannels in use PCI/MSI[-X] masking is solely
489	 * controlled by the hypervisor.
490	 */
491	pci_msi_ignore_mask = 1;
492}
493
494#else /* CONFIG_PCI_MSI */
495static inline void xen_setup_pci_msi(void) { }
496#endif /* CONFIG_PCI_MSI */
497
498int __init pci_xen_init(void)
499{
500	if (!xen_pv_domain() || xen_initial_domain())
501		return -ENODEV;
502
503	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
504
505	pcibios_set_cache_line_size();
506
507	pcibios_enable_irq = xen_pcifront_enable_irq;
508	pcibios_disable_irq = NULL;
509
 
510	/* Keep ACPI out of the picture */
511	acpi_noirq_set();
 
512
513	xen_setup_pci_msi();
 
 
 
 
 
514	return 0;
515}
516
517#ifdef CONFIG_PCI_MSI
518static void __init xen_hvm_msi_init(void)
519{
520	if (!apic_is_disabled) {
521		/*
522		 * If hardware supports (x2)APIC virtualization (as indicated
523		 * by hypervisor's leaf 4) then we don't need to use pirqs/
524		 * event channels for MSI handling and instead use regular
525		 * APIC processing
526		 */
527		uint32_t eax = cpuid_eax(xen_cpuid_base() + 4);
528
529		if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) ||
530		    ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && boot_cpu_has(X86_FEATURE_APIC)))
531			return;
532	}
533	xen_setup_pci_msi();
 
 
534}
535#endif
536
537int __init pci_xen_hvm_init(void)
538{
539	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
540		return 0;
541
542#ifdef CONFIG_ACPI
543	/*
544	 * We don't want to change the actual ACPI delivery model,
545	 * just how GSIs get registered.
546	 */
547	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
548	__acpi_unregister_gsi = NULL;
549#endif
550
551#ifdef CONFIG_PCI_MSI
552	/*
553	 * We need to wait until after x2apic is initialized
554	 * before we can set MSI IRQ ops.
555	 */
556	x86_platform.apic_post_init = xen_hvm_msi_init;
557#endif
558	return 0;
559}
560
561#ifdef CONFIG_XEN_PV_DOM0
562int __init pci_xen_initial_domain(void)
563{
564	int irq;
565
566	xen_setup_pci_msi();
 
 
 
 
 
567	__acpi_register_gsi = acpi_register_gsi_xen;
568	__acpi_unregister_gsi = NULL;
569	/*
570	 * Pre-allocate the legacy IRQs.  Use NR_LEGACY_IRQS here
571	 * because we don't have a PIC and thus nr_legacy_irqs() is zero.
572	 */
573	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
574		int trigger, polarity;
575
576		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
577			continue;
578
579		xen_register_pirq(irq,
580			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
581			true /* Map GSI to PIRQ */);
582	}
583	if (0 == nr_ioapics) {
584		for (irq = 0; irq < nr_legacy_irqs(); irq++)
585			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
586	}
587	return 0;
588}
589#endif
590
v4.6
 
  1/*
  2 * Xen PCI - handle PCI (INTx) and MSI infrastructure calls for PV, HVM and
  3 * initial domain support. We also handle the DSDT _PRT callbacks for GSI's
  4 * used in HVM and initial domain mode (PV does not parse ACPI, so it has no
  5 * concept of GSIs). Under PV we hook under the pnbbios API for IRQs and
  6 * 0xcf8 PCI configuration read/write.
  7 *
  8 *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
  9 *           Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
 10 *           Stefano Stabellini <stefano.stabellini@eu.citrix.com>
 11 */
 12#include <linux/module.h>
 13#include <linux/init.h>
 14#include <linux/pci.h>
 15#include <linux/acpi.h>
 16
 17#include <linux/io.h>
 18#include <asm/io_apic.h>
 19#include <asm/pci_x86.h>
 20
 21#include <asm/xen/hypervisor.h>
 22
 23#include <xen/features.h>
 24#include <xen/events.h>
 
 25#include <asm/xen/pci.h>
 26#include <asm/xen/cpuid.h>
 27#include <asm/apic.h>
 
 28#include <asm/i8259.h>
 29
 30static int xen_pcifront_enable_irq(struct pci_dev *dev)
 31{
 32	int rc;
 33	int share = 1;
 34	int pirq;
 35	u8 gsi;
 36
 37	rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
 38	if (rc < 0) {
 39		dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
 40			 rc);
 41		return rc;
 42	}
 43	/* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/
 44	pirq = gsi;
 45
 46	if (gsi < nr_legacy_irqs())
 47		share = 0;
 48
 49	rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
 50	if (rc < 0) {
 51		dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n",
 52			 gsi, pirq, rc);
 53		return rc;
 54	}
 55
 56	dev->irq = rc;
 57	dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq);
 58	return 0;
 59}
 60
 61#ifdef CONFIG_ACPI
 62static int xen_register_pirq(u32 gsi, int gsi_override, int triggering,
 63			     bool set_pirq)
 64{
 65	int rc, pirq = -1, irq = -1;
 66	struct physdev_map_pirq map_irq;
 67	int shareable = 0;
 68	char *name;
 69
 70	irq = xen_irq_from_gsi(gsi);
 71	if (irq > 0)
 72		return irq;
 73
 74	if (set_pirq)
 75		pirq = gsi;
 76
 77	map_irq.domid = DOMID_SELF;
 78	map_irq.type = MAP_PIRQ_TYPE_GSI;
 79	map_irq.index = gsi;
 80	map_irq.pirq = pirq;
 81
 82	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
 83	if (rc) {
 84		printk(KERN_WARNING "xen map irq failed %d\n", rc);
 85		return -1;
 86	}
 87
 88	if (triggering == ACPI_EDGE_SENSITIVE) {
 89		shareable = 0;
 90		name = "ioapic-edge";
 91	} else {
 92		shareable = 1;
 93		name = "ioapic-level";
 94	}
 95
 96	if (gsi_override >= 0)
 97		gsi = gsi_override;
 98
 99	irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
100	if (irq < 0)
101		goto out;
102
103	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi);
104out:
105	return irq;
106}
107
108static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
109				     int trigger, int polarity)
110{
111	if (!xen_hvm_domain())
112		return -1;
113
114	return xen_register_pirq(gsi, -1 /* no GSI override */, trigger,
115				 false /* no mapping of GSI to PIRQ */);
116}
117
118#ifdef CONFIG_XEN_DOM0
119static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity)
120{
121	int rc, irq;
122	struct physdev_setup_gsi setup_gsi;
123
124	if (!xen_pv_domain())
125		return -1;
126
127	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
128			gsi, triggering, polarity);
129
130	irq = xen_register_pirq(gsi, gsi_override, triggering, true);
131
132	setup_gsi.gsi = gsi;
133	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
134	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
135
136	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
137	if (rc == -EEXIST)
138		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
139	else if (rc) {
140		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
141				gsi, rc);
142	}
143
144	return irq;
145}
146
147static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
148				 int trigger, int polarity)
149{
150	return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity);
151}
152#endif
153#endif
154
155#if defined(CONFIG_PCI_MSI)
156#include <linux/msi.h>
157#include <asm/msidef.h>
158
159struct xen_pci_frontend_ops *xen_pci_frontend;
160EXPORT_SYMBOL_GPL(xen_pci_frontend);
161
 
 
 
 
 
 
 
162static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
163{
164	int irq, ret, i;
165	struct msi_desc *msidesc;
166	int *v;
167
168	if (type == PCI_CAP_ID_MSI && nvec > 1)
169		return 1;
170
171	v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
172	if (!v)
173		return -ENOMEM;
174
175	if (type == PCI_CAP_ID_MSIX)
176		ret = xen_pci_frontend_enable_msix(dev, v, nvec);
177	else
178		ret = xen_pci_frontend_enable_msi(dev, v);
179	if (ret)
180		goto error;
181	i = 0;
182	for_each_pci_msi_entry(msidesc, dev) {
183		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i],
184					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
185					       (type == PCI_CAP_ID_MSIX) ?
186					       "pcifront-msi-x" :
187					       "pcifront-msi",
188						DOMID_SELF);
189		if (irq < 0) {
190			ret = irq;
191			goto free;
192		}
193		i++;
194	}
195	kfree(v);
196	return 0;
197
198error:
199	if (ret == -ENOSYS)
200		dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n");
201	else if (ret)
202		dev_err(&dev->dev, "Xen PCI frontend error: %d!\n", ret);
203free:
204	kfree(v);
205	return ret;
206}
207
208#define XEN_PIRQ_MSI_DATA  (MSI_DATA_TRIGGER_EDGE | \
209		MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0))
210
211static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
212		struct msi_msg *msg)
213{
214	/* We set vector == 0 to tell the hypervisor we don't care about it,
215	 * but we want a pirq setup instead.
216	 * We use the dest_id field to pass the pirq that we want. */
217	msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq);
218	msg->address_lo =
219		MSI_ADDR_BASE_LO |
220		MSI_ADDR_DEST_MODE_PHYSICAL |
221		MSI_ADDR_REDIRECTION_CPU |
222		MSI_ADDR_DEST_ID(pirq);
223
224	msg->data = XEN_PIRQ_MSI_DATA;
225}
226
227static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
228{
229	int irq, pirq;
230	struct msi_desc *msidesc;
231	struct msi_msg msg;
232
233	if (type == PCI_CAP_ID_MSI && nvec > 1)
234		return 1;
235
236	for_each_pci_msi_entry(msidesc, dev) {
237		__pci_read_msi_msg(msidesc, &msg);
238		pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) |
239			((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff);
240		if (msg.data != XEN_PIRQ_MSI_DATA ||
241		    xen_irq_from_pirq(pirq) < 0) {
242			pirq = xen_allocate_pirq_msi(dev, msidesc);
243			if (pirq < 0) {
244				irq = -ENODEV;
245				goto error;
246			}
247			xen_msi_compose_msg(dev, pirq, &msg);
248			__pci_write_msi_msg(msidesc, &msg);
249			dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq);
250		} else {
251			dev_dbg(&dev->dev,
252				"xen: msi already bound to pirq=%d\n", pirq);
253		}
 
 
 
254		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq,
255					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
256					       (type == PCI_CAP_ID_MSIX) ?
257					       "msi-x" : "msi",
258					       DOMID_SELF);
259		if (irq < 0)
260			goto error;
261		dev_dbg(&dev->dev,
262			"xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
263	}
264	return 0;
265
266error:
267	dev_err(&dev->dev,
268		"Xen PCI frontend has not registered MSI/MSI-X support!\n");
269	return irq;
270}
271
272#ifdef CONFIG_XEN_DOM0
273static bool __read_mostly pci_seg_supported = true;
274
275static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
276{
277	int ret = 0;
278	struct msi_desc *msidesc;
279
280	for_each_pci_msi_entry(msidesc, dev) {
281		struct physdev_map_pirq map_irq;
282		domid_t domid;
283
284		domid = ret = xen_find_device_domain_owner(dev);
285		/* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED,
286		 * hence check ret value for < 0. */
287		if (ret < 0)
288			domid = DOMID_SELF;
289
290		memset(&map_irq, 0, sizeof(map_irq));
291		map_irq.domid = domid;
292		map_irq.type = MAP_PIRQ_TYPE_MSI_SEG;
293		map_irq.index = -1;
294		map_irq.pirq = -1;
295		map_irq.bus = dev->bus->number |
296			      (pci_domain_nr(dev->bus) << 16);
297		map_irq.devfn = dev->devfn;
298
299		if (type == PCI_CAP_ID_MSI && nvec > 1) {
300			map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI;
301			map_irq.entry_nr = nvec;
302		} else if (type == PCI_CAP_ID_MSIX) {
303			int pos;
304			unsigned long flags;
305			u32 table_offset, bir;
306
307			pos = dev->msix_cap;
308			pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
309					      &table_offset);
310			bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
311			flags = pci_resource_flags(dev, bir);
312			if (!flags || (flags & IORESOURCE_UNSET))
313				return -EINVAL;
314
315			map_irq.table_base = pci_resource_start(dev, bir);
316			map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
317		}
318
319		ret = -EINVAL;
320		if (pci_seg_supported)
321			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
322						    &map_irq);
323		if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) {
324			/*
325			 * If MAP_PIRQ_TYPE_MULTI_MSI is not available
326			 * there's nothing else we can do in this case.
327			 * Just set ret > 0 so driver can retry with
328			 * single MSI.
329			 */
330			ret = 1;
331			goto out;
332		}
333		if (ret == -EINVAL && !pci_domain_nr(dev->bus)) {
334			map_irq.type = MAP_PIRQ_TYPE_MSI;
335			map_irq.index = -1;
336			map_irq.pirq = -1;
337			map_irq.bus = dev->bus->number;
338			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
339						    &map_irq);
340			if (ret != -EINVAL)
341				pci_seg_supported = false;
342		}
343		if (ret) {
344			dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
345				 ret, domid);
346			goto out;
347		}
348
349		ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq,
350		                               (type == PCI_CAP_ID_MSI) ? nvec : 1,
351		                               (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi",
352		                               domid);
353		if (ret < 0)
354			goto out;
355	}
356	ret = 0;
357out:
358	return ret;
359}
360
361static void xen_initdom_restore_msi_irqs(struct pci_dev *dev)
362{
363	int ret = 0;
364
 
 
 
365	if (pci_seg_supported) {
366		struct physdev_pci_device restore_ext;
367
368		restore_ext.seg = pci_domain_nr(dev->bus);
369		restore_ext.bus = dev->bus->number;
370		restore_ext.devfn = dev->devfn;
371		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext,
372					&restore_ext);
373		if (ret == -ENOSYS)
374			pci_seg_supported = false;
375		WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret);
376	}
377	if (!pci_seg_supported) {
378		struct physdev_restore_msi restore;
379
380		restore.bus = dev->bus->number;
381		restore.devfn = dev->devfn;
382		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore);
383		WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret);
384	}
 
385}
386#endif
 
 
387
388static void xen_teardown_msi_irqs(struct pci_dev *dev)
389{
390	struct msi_desc *msidesc;
 
 
 
 
 
 
 
 
 
 
391
392	msidesc = first_pci_msi_entry(dev);
393	if (msidesc->msi_attrib.is_msix)
 
394		xen_pci_frontend_disable_msix(dev);
395	else
396		xen_pci_frontend_disable_msi(dev);
397
398	/* Free the IRQ's and the msidesc using the generic code. */
399	default_teardown_msi_irqs(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
400}
401
402static void xen_teardown_msi_irq(unsigned int irq)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
403{
404	xen_destroy_irq(irq);
 
 
 
 
 
 
 
 
 
 
405}
406
407#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
408
409int __init pci_xen_init(void)
410{
411	if (!xen_pv_domain() || xen_initial_domain())
412		return -ENODEV;
413
414	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
415
416	pcibios_set_cache_line_size();
417
418	pcibios_enable_irq = xen_pcifront_enable_irq;
419	pcibios_disable_irq = NULL;
420
421#ifdef CONFIG_ACPI
422	/* Keep ACPI out of the picture */
423	acpi_noirq = 1;
424#endif
425
426#ifdef CONFIG_PCI_MSI
427	x86_msi.setup_msi_irqs = xen_setup_msi_irqs;
428	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
429	x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
430	pci_msi_ignore_mask = 1;
431#endif
432	return 0;
433}
434
435#ifdef CONFIG_PCI_MSI
436void __init xen_msi_init(void)
437{
438	if (!disable_apic) {
439		/*
440		 * If hardware supports (x2)APIC virtualization (as indicated
441		 * by hypervisor's leaf 4) then we don't need to use pirqs/
442		 * event channels for MSI handling and instead use regular
443		 * APIC processing
444		 */
445		uint32_t eax = cpuid_eax(xen_cpuid_base() + 4);
446
447		if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) ||
448		    ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && cpu_has_apic))
449			return;
450	}
451
452	x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
453	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
454}
455#endif
456
457int __init pci_xen_hvm_init(void)
458{
459	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
460		return 0;
461
462#ifdef CONFIG_ACPI
463	/*
464	 * We don't want to change the actual ACPI delivery model,
465	 * just how GSIs get registered.
466	 */
467	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
468	__acpi_unregister_gsi = NULL;
469#endif
470
471#ifdef CONFIG_PCI_MSI
472	/*
473	 * We need to wait until after x2apic is initialized
474	 * before we can set MSI IRQ ops.
475	 */
476	x86_platform.apic_post_init = xen_msi_init;
477#endif
478	return 0;
479}
480
481#ifdef CONFIG_XEN_DOM0
482int __init pci_xen_initial_domain(void)
483{
484	int irq;
485
486#ifdef CONFIG_PCI_MSI
487	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
488	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
489	x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
490	pci_msi_ignore_mask = 1;
491#endif
492	__acpi_register_gsi = acpi_register_gsi_xen;
493	__acpi_unregister_gsi = NULL;
494	/* Pre-allocate legacy irqs */
495	for (irq = 0; irq < nr_legacy_irqs(); irq++) {
 
 
 
496		int trigger, polarity;
497
498		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
499			continue;
500
501		xen_register_pirq(irq, -1 /* no GSI override */,
502			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
503			true /* Map GSI to PIRQ */);
504	}
505	if (0 == nr_ioapics) {
506		for (irq = 0; irq < nr_legacy_irqs(); irq++)
507			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
508	}
509	return 0;
510}
 
511
512struct xen_device_domain_owner {
513	domid_t domain;
514	struct pci_dev *dev;
515	struct list_head list;
516};
517
518static DEFINE_SPINLOCK(dev_domain_list_spinlock);
519static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list);
520
521static struct xen_device_domain_owner *find_device(struct pci_dev *dev)
522{
523	struct xen_device_domain_owner *owner;
524
525	list_for_each_entry(owner, &dev_domain_list, list) {
526		if (owner->dev == dev)
527			return owner;
528	}
529	return NULL;
530}
531
532int xen_find_device_domain_owner(struct pci_dev *dev)
533{
534	struct xen_device_domain_owner *owner;
535	int domain = -ENODEV;
536
537	spin_lock(&dev_domain_list_spinlock);
538	owner = find_device(dev);
539	if (owner)
540		domain = owner->domain;
541	spin_unlock(&dev_domain_list_spinlock);
542	return domain;
543}
544EXPORT_SYMBOL_GPL(xen_find_device_domain_owner);
545
546int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain)
547{
548	struct xen_device_domain_owner *owner;
549
550	owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL);
551	if (!owner)
552		return -ENODEV;
553
554	spin_lock(&dev_domain_list_spinlock);
555	if (find_device(dev)) {
556		spin_unlock(&dev_domain_list_spinlock);
557		kfree(owner);
558		return -EEXIST;
559	}
560	owner->domain = domain;
561	owner->dev = dev;
562	list_add_tail(&owner->list, &dev_domain_list);
563	spin_unlock(&dev_domain_list_spinlock);
564	return 0;
565}
566EXPORT_SYMBOL_GPL(xen_register_device_domain_owner);
567
568int xen_unregister_device_domain_owner(struct pci_dev *dev)
569{
570	struct xen_device_domain_owner *owner;
571
572	spin_lock(&dev_domain_list_spinlock);
573	owner = find_device(dev);
574	if (!owner) {
575		spin_unlock(&dev_domain_list_spinlock);
576		return -ENODEV;
577	}
578	list_del(&owner->list);
579	spin_unlock(&dev_domain_list_spinlock);
580	kfree(owner);
581	return 0;
582}
583EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner);
584#endif