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v6.2
  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 0;
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 0;
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 = 0;
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
399static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
400{
401	if (dev->msix_enabled)
402		xen_pci_frontend_disable_msix(dev);
403	else
404		xen_pci_frontend_disable_msi(dev);
405
406	xen_teardown_msi_irqs(dev);
407}
408
409static int xen_msi_domain_alloc_irqs(struct irq_domain *domain,
410				     struct device *dev,  int nvec)
411{
412	int type;
413
414	if (WARN_ON_ONCE(!dev_is_pci(dev)))
415		return -EINVAL;
416
417	type = to_pci_dev(dev)->msix_enabled ? PCI_CAP_ID_MSIX : PCI_CAP_ID_MSI;
418
419	return xen_msi_ops.setup_msi_irqs(to_pci_dev(dev), nvec, type);
420}
421
422static void xen_msi_domain_free_irqs(struct irq_domain *domain,
423				     struct device *dev)
424{
425	if (WARN_ON_ONCE(!dev_is_pci(dev)))
426		return;
427
428	xen_msi_ops.teardown_msi_irqs(to_pci_dev(dev));
429}
430
431static struct msi_domain_ops xen_pci_msi_domain_ops = {
432	.domain_alloc_irqs	= xen_msi_domain_alloc_irqs,
433	.domain_free_irqs	= xen_msi_domain_free_irqs,
434};
435
436static struct msi_domain_info xen_pci_msi_domain_info = {
437	.flags			= MSI_FLAG_PCI_MSIX | MSI_FLAG_FREE_MSI_DESCS | MSI_FLAG_DEV_SYSFS,
438	.ops			= &xen_pci_msi_domain_ops,
439};
440
441/*
442 * This irq domain is a blatant violation of the irq domain design, but
443 * distangling XEN into real irq domains is not a job for mere mortals with
444 * limited XENology. But it's the least dangerous way for a mere mortal to
445 * get rid of the arch_*_msi_irqs() hackery in order to store the irq
446 * domain pointer in struct device. This irq domain wrappery allows to do
447 * that without breaking XEN terminally.
448 */
449static __init struct irq_domain *xen_create_pci_msi_domain(void)
450{
451	struct irq_domain *d = NULL;
452	struct fwnode_handle *fn;
453
454	fn = irq_domain_alloc_named_fwnode("XEN-MSI");
455	if (fn)
456		d = msi_create_irq_domain(fn, &xen_pci_msi_domain_info, NULL);
457
458	/* FIXME: No idea how to survive if this fails */
459	BUG_ON(!d);
460
461	return d;
462}
463
464static __init void xen_setup_pci_msi(void)
465{
466	if (xen_pv_domain()) {
467		if (xen_initial_domain())
468			xen_msi_ops.setup_msi_irqs = xen_initdom_setup_msi_irqs;
469		else
470			xen_msi_ops.setup_msi_irqs = xen_setup_msi_irqs;
471		xen_msi_ops.teardown_msi_irqs = xen_pv_teardown_msi_irqs;
472	} else if (xen_hvm_domain()) {
473		xen_msi_ops.setup_msi_irqs = xen_hvm_setup_msi_irqs;
474		xen_msi_ops.teardown_msi_irqs = xen_teardown_msi_irqs;
475	} else {
476		WARN_ON_ONCE(1);
477		return;
478	}
479
480	/*
481	 * Override the PCI/MSI irq domain init function. No point
482	 * in allocating the native domain and never use it.
483	 */
484	x86_init.irqs.create_pci_msi_domain = xen_create_pci_msi_domain;
485	/*
486	 * With XEN PIRQ/Eventchannels in use PCI/MSI[-X] masking is solely
487	 * controlled by the hypervisor.
488	 */
489	pci_msi_ignore_mask = 1;
490}
491
492#else /* CONFIG_PCI_MSI */
493static inline void xen_setup_pci_msi(void) { }
494#endif /* CONFIG_PCI_MSI */
495
496int __init pci_xen_init(void)
497{
498	if (!xen_pv_domain() || xen_initial_domain())
499		return -ENODEV;
500
501	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
502
503	pcibios_set_cache_line_size();
504
505	pcibios_enable_irq = xen_pcifront_enable_irq;
506	pcibios_disable_irq = NULL;
507
508	/* Keep ACPI out of the picture */
509	acpi_noirq_set();
510
511	xen_setup_pci_msi();
 
 
 
 
 
512	return 0;
513}
514
515#ifdef CONFIG_PCI_MSI
516static void __init xen_hvm_msi_init(void)
517{
518	if (!disable_apic) {
519		/*
520		 * If hardware supports (x2)APIC virtualization (as indicated
521		 * by hypervisor's leaf 4) then we don't need to use pirqs/
522		 * event channels for MSI handling and instead use regular
523		 * APIC processing
524		 */
525		uint32_t eax = cpuid_eax(xen_cpuid_base() + 4);
526
527		if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) ||
528		    ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && boot_cpu_has(X86_FEATURE_APIC)))
529			return;
530	}
531	xen_setup_pci_msi();
 
 
532}
533#endif
534
535int __init pci_xen_hvm_init(void)
536{
537	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
538		return 0;
539
540#ifdef CONFIG_ACPI
541	/*
542	 * We don't want to change the actual ACPI delivery model,
543	 * just how GSIs get registered.
544	 */
545	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
546	__acpi_unregister_gsi = NULL;
547#endif
548
549#ifdef CONFIG_PCI_MSI
550	/*
551	 * We need to wait until after x2apic is initialized
552	 * before we can set MSI IRQ ops.
553	 */
554	x86_platform.apic_post_init = xen_hvm_msi_init;
555#endif
556	return 0;
557}
558
559#ifdef CONFIG_XEN_PV_DOM0
560int __init pci_xen_initial_domain(void)
561{
562	int irq;
563
564	xen_setup_pci_msi();
 
 
 
 
 
565	__acpi_register_gsi = acpi_register_gsi_xen;
566	__acpi_unregister_gsi = NULL;
567	/*
568	 * Pre-allocate the legacy IRQs.  Use NR_LEGACY_IRQS here
569	 * because we don't have a PIC and thus nr_legacy_irqs() is zero.
570	 */
571	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
572		int trigger, polarity;
573
574		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
575			continue;
576
577		xen_register_pirq(irq,
578			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
579			true /* Map GSI to PIRQ */);
580	}
581	if (0 == nr_ioapics) {
582		for (irq = 0; irq < nr_legacy_irqs(); irq++)
583			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
584	}
585	return 0;
586}
587#endif
588
v4.17
 
  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/export.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		pirq = xen_allocate_pirq_msi(dev, msidesc);
238		if (pirq < 0) {
239			irq = -ENODEV;
240			goto error;
241		}
242		xen_msi_compose_msg(dev, pirq, &msg);
243		__pci_write_msi_msg(msidesc, &msg);
244		dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq);
245		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq,
246					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
247					       (type == PCI_CAP_ID_MSIX) ?
248					       "msi-x" : "msi",
249					       DOMID_SELF);
250		if (irq < 0)
251			goto error;
252		dev_dbg(&dev->dev,
253			"xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
254	}
255	return 0;
256
257error:
258	dev_err(&dev->dev, "Failed to create MSI%s! ret=%d!\n",
259		type == PCI_CAP_ID_MSI ? "" : "-X", irq);
260	return irq;
261}
262
263#ifdef CONFIG_XEN_DOM0
264static bool __read_mostly pci_seg_supported = true;
265
266static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
267{
268	int ret = 0;
269	struct msi_desc *msidesc;
270
271	for_each_pci_msi_entry(msidesc, dev) {
272		struct physdev_map_pirq map_irq;
273		domid_t domid;
274
275		domid = ret = xen_find_device_domain_owner(dev);
276		/* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED,
277		 * hence check ret value for < 0. */
278		if (ret < 0)
279			domid = DOMID_SELF;
280
281		memset(&map_irq, 0, sizeof(map_irq));
282		map_irq.domid = domid;
283		map_irq.type = MAP_PIRQ_TYPE_MSI_SEG;
284		map_irq.index = -1;
285		map_irq.pirq = -1;
286		map_irq.bus = dev->bus->number |
287			      (pci_domain_nr(dev->bus) << 16);
288		map_irq.devfn = dev->devfn;
289
290		if (type == PCI_CAP_ID_MSI && nvec > 1) {
291			map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI;
292			map_irq.entry_nr = nvec;
293		} else if (type == PCI_CAP_ID_MSIX) {
294			int pos;
295			unsigned long flags;
296			u32 table_offset, bir;
297
298			pos = dev->msix_cap;
299			pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
300					      &table_offset);
301			bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
302			flags = pci_resource_flags(dev, bir);
303			if (!flags || (flags & IORESOURCE_UNSET))
304				return -EINVAL;
305
306			map_irq.table_base = pci_resource_start(dev, bir);
307			map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
308		}
309
310		ret = -EINVAL;
311		if (pci_seg_supported)
312			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
313						    &map_irq);
314		if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) {
315			/*
316			 * If MAP_PIRQ_TYPE_MULTI_MSI is not available
317			 * there's nothing else we can do in this case.
318			 * Just set ret > 0 so driver can retry with
319			 * single MSI.
320			 */
321			ret = 1;
322			goto out;
323		}
324		if (ret == -EINVAL && !pci_domain_nr(dev->bus)) {
325			map_irq.type = MAP_PIRQ_TYPE_MSI;
326			map_irq.index = -1;
327			map_irq.pirq = -1;
328			map_irq.bus = dev->bus->number;
329			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
330						    &map_irq);
331			if (ret != -EINVAL)
332				pci_seg_supported = false;
333		}
334		if (ret) {
335			dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
336				 ret, domid);
337			goto out;
338		}
339
340		ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq,
341		                               (type == PCI_CAP_ID_MSI) ? nvec : 1,
342		                               (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi",
343		                               domid);
344		if (ret < 0)
345			goto out;
346	}
347	ret = 0;
348out:
349	return ret;
350}
351
352static void xen_initdom_restore_msi_irqs(struct pci_dev *dev)
353{
354	int ret = 0;
355
 
 
 
356	if (pci_seg_supported) {
357		struct physdev_pci_device restore_ext;
358
359		restore_ext.seg = pci_domain_nr(dev->bus);
360		restore_ext.bus = dev->bus->number;
361		restore_ext.devfn = dev->devfn;
362		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext,
363					&restore_ext);
364		if (ret == -ENOSYS)
365			pci_seg_supported = false;
366		WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret);
367	}
368	if (!pci_seg_supported) {
369		struct physdev_restore_msi restore;
370
371		restore.bus = dev->bus->number;
372		restore.devfn = dev->devfn;
373		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore);
374		WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret);
375	}
 
376}
377#endif
 
 
378
379static void xen_teardown_msi_irqs(struct pci_dev *dev)
380{
381	struct msi_desc *msidesc;
 
382
383	msidesc = first_pci_msi_entry(dev);
384	if (msidesc->msi_attrib.is_msix)
 
 
 
 
 
 
 
 
385		xen_pci_frontend_disable_msix(dev);
386	else
387		xen_pci_frontend_disable_msi(dev);
388
389	/* Free the IRQ's and the msidesc using the generic code. */
390	default_teardown_msi_irqs(dev);
 
 
 
 
 
 
 
 
 
 
 
 
391}
392
393static void xen_teardown_msi_irq(unsigned int irq)
 
394{
395	xen_destroy_irq(irq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
396}
397
398#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
399
400int __init pci_xen_init(void)
401{
402	if (!xen_pv_domain() || xen_initial_domain())
403		return -ENODEV;
404
405	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
406
407	pcibios_set_cache_line_size();
408
409	pcibios_enable_irq = xen_pcifront_enable_irq;
410	pcibios_disable_irq = NULL;
411
412	/* Keep ACPI out of the picture */
413	acpi_noirq_set();
414
415#ifdef CONFIG_PCI_MSI
416	x86_msi.setup_msi_irqs = xen_setup_msi_irqs;
417	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
418	x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
419	pci_msi_ignore_mask = 1;
420#endif
421	return 0;
422}
423
424#ifdef CONFIG_PCI_MSI
425void __init xen_msi_init(void)
426{
427	if (!disable_apic) {
428		/*
429		 * If hardware supports (x2)APIC virtualization (as indicated
430		 * by hypervisor's leaf 4) then we don't need to use pirqs/
431		 * event channels for MSI handling and instead use regular
432		 * APIC processing
433		 */
434		uint32_t eax = cpuid_eax(xen_cpuid_base() + 4);
435
436		if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) ||
437		    ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && boot_cpu_has(X86_FEATURE_APIC)))
438			return;
439	}
440
441	x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
442	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
443}
444#endif
445
446int __init pci_xen_hvm_init(void)
447{
448	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
449		return 0;
450
451#ifdef CONFIG_ACPI
452	/*
453	 * We don't want to change the actual ACPI delivery model,
454	 * just how GSIs get registered.
455	 */
456	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
457	__acpi_unregister_gsi = NULL;
458#endif
459
460#ifdef CONFIG_PCI_MSI
461	/*
462	 * We need to wait until after x2apic is initialized
463	 * before we can set MSI IRQ ops.
464	 */
465	x86_platform.apic_post_init = xen_msi_init;
466#endif
467	return 0;
468}
469
470#ifdef CONFIG_XEN_DOM0
471int __init pci_xen_initial_domain(void)
472{
473	int irq;
474
475#ifdef CONFIG_PCI_MSI
476	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
477	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
478	x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
479	pci_msi_ignore_mask = 1;
480#endif
481	__acpi_register_gsi = acpi_register_gsi_xen;
482	__acpi_unregister_gsi = NULL;
483	/*
484	 * Pre-allocate the legacy IRQs.  Use NR_LEGACY_IRQS here
485	 * because we don't have a PIC and thus nr_legacy_irqs() is zero.
486	 */
487	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
488		int trigger, polarity;
489
490		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
491			continue;
492
493		xen_register_pirq(irq, -1 /* no GSI override */,
494			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
495			true /* Map GSI to PIRQ */);
496	}
497	if (0 == nr_ioapics) {
498		for (irq = 0; irq < nr_legacy_irqs(); irq++)
499			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
500	}
501	return 0;
502}
 
503
504struct xen_device_domain_owner {
505	domid_t domain;
506	struct pci_dev *dev;
507	struct list_head list;
508};
509
510static DEFINE_SPINLOCK(dev_domain_list_spinlock);
511static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list);
512
513static struct xen_device_domain_owner *find_device(struct pci_dev *dev)
514{
515	struct xen_device_domain_owner *owner;
516
517	list_for_each_entry(owner, &dev_domain_list, list) {
518		if (owner->dev == dev)
519			return owner;
520	}
521	return NULL;
522}
523
524int xen_find_device_domain_owner(struct pci_dev *dev)
525{
526	struct xen_device_domain_owner *owner;
527	int domain = -ENODEV;
528
529	spin_lock(&dev_domain_list_spinlock);
530	owner = find_device(dev);
531	if (owner)
532		domain = owner->domain;
533	spin_unlock(&dev_domain_list_spinlock);
534	return domain;
535}
536EXPORT_SYMBOL_GPL(xen_find_device_domain_owner);
537
538int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain)
539{
540	struct xen_device_domain_owner *owner;
541
542	owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL);
543	if (!owner)
544		return -ENODEV;
545
546	spin_lock(&dev_domain_list_spinlock);
547	if (find_device(dev)) {
548		spin_unlock(&dev_domain_list_spinlock);
549		kfree(owner);
550		return -EEXIST;
551	}
552	owner->domain = domain;
553	owner->dev = dev;
554	list_add_tail(&owner->list, &dev_domain_list);
555	spin_unlock(&dev_domain_list_spinlock);
556	return 0;
557}
558EXPORT_SYMBOL_GPL(xen_register_device_domain_owner);
559
560int xen_unregister_device_domain_owner(struct pci_dev *dev)
561{
562	struct xen_device_domain_owner *owner;
563
564	spin_lock(&dev_domain_list_spinlock);
565	owner = find_device(dev);
566	if (!owner) {
567		spin_unlock(&dev_domain_list_spinlock);
568		return -ENODEV;
569	}
570	list_del(&owner->list);
571	spin_unlock(&dev_domain_list_spinlock);
572	kfree(owner);
573	return 0;
574}
575EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner);
576#endif