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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
v5.14.15
  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 <asm/xen/pci.h>
 27#include <asm/xen/cpuid.h>
 28#include <asm/apic.h>
 29#include <asm/acpi.h>
 30#include <asm/i8259.h>
 31
 32static int xen_pcifront_enable_irq(struct pci_dev *dev)
 33{
 34	int rc;
 35	int share = 1;
 36	int pirq;
 37	u8 gsi;
 38
 39	rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
 40	if (rc < 0) {
 41		dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
 42			 rc);
 43		return rc;
 44	}
 45	/* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/
 46	pirq = gsi;
 47
 48	if (gsi < nr_legacy_irqs())
 49		share = 0;
 50
 51	rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
 52	if (rc < 0) {
 53		dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n",
 54			 gsi, pirq, rc);
 55		return rc;
 56	}
 57
 58	dev->irq = rc;
 59	dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq);
 60	return 0;
 61}
 62
 63#ifdef CONFIG_ACPI
 64static int xen_register_pirq(u32 gsi, int triggering, bool set_pirq)
 65{
 66	int rc, pirq = -1, irq;
 67	struct physdev_map_pirq map_irq;
 68	int shareable = 0;
 69	char *name;
 70
 71	irq = xen_irq_from_gsi(gsi);
 72	if (irq > 0)
 73		return irq;
 74
 75	if (set_pirq)
 76		pirq = gsi;
 77
 78	map_irq.domid = DOMID_SELF;
 79	map_irq.type = MAP_PIRQ_TYPE_GSI;
 80	map_irq.index = gsi;
 81	map_irq.pirq = pirq;
 82
 83	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
 84	if (rc) {
 85		printk(KERN_WARNING "xen map irq failed %d\n", rc);
 86		return -1;
 87	}
 88
 89	if (triggering == ACPI_EDGE_SENSITIVE) {
 90		shareable = 0;
 91		name = "ioapic-edge";
 92	} else {
 93		shareable = 1;
 94		name = "ioapic-level";
 95	}
 96
 97	irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
 98	if (irq < 0)
 99		goto out;
100
101	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi);
102out:
103	return irq;
104}
105
106static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
107				     int trigger, int polarity)
108{
109	if (!xen_hvm_domain())
110		return -1;
111
112	return xen_register_pirq(gsi, trigger,
113				 false /* no mapping of GSI to PIRQ */);
114}
115
116#ifdef CONFIG_XEN_DOM0
117static int xen_register_gsi(u32 gsi, int triggering, int polarity)
118{
119	int rc, irq;
120	struct physdev_setup_gsi setup_gsi;
121
122	if (!xen_pv_domain())
123		return -1;
124
125	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
126			gsi, triggering, polarity);
127
128	irq = xen_register_pirq(gsi, triggering, true);
129
130	setup_gsi.gsi = gsi;
131	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
132	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
133
134	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
135	if (rc == -EEXIST)
136		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
137	else if (rc) {
138		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
139				gsi, rc);
140	}
141
142	return irq;
143}
144
145static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
146				 int trigger, int polarity)
147{
148	return xen_register_gsi(gsi, trigger, polarity);
149}
150#endif
151#endif
152
153#if defined(CONFIG_PCI_MSI)
154#include <linux/msi.h>
155
156struct xen_pci_frontend_ops *xen_pci_frontend;
157EXPORT_SYMBOL_GPL(xen_pci_frontend);
158
159struct xen_msi_ops {
160	int (*setup_msi_irqs)(struct pci_dev *dev, int nvec, int type);
161	void (*teardown_msi_irqs)(struct pci_dev *dev);
162};
163
164static struct xen_msi_ops xen_msi_ops __ro_after_init;
165
166static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
167{
168	int irq, ret, i;
169	struct msi_desc *msidesc;
170	int *v;
171
172	if (type == PCI_CAP_ID_MSI && nvec > 1)
173		return 1;
174
175	v = kcalloc(max(1, nvec), sizeof(int), GFP_KERNEL);
176	if (!v)
177		return -ENOMEM;
178
179	if (type == PCI_CAP_ID_MSIX)
180		ret = xen_pci_frontend_enable_msix(dev, v, nvec);
181	else
182		ret = xen_pci_frontend_enable_msi(dev, v);
183	if (ret)
184		goto error;
185	i = 0;
186	for_each_pci_msi_entry(msidesc, dev) {
187		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i],
188					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
189					       (type == PCI_CAP_ID_MSIX) ?
190					       "pcifront-msi-x" :
191					       "pcifront-msi",
192						DOMID_SELF);
193		if (irq < 0) {
194			ret = irq;
195			goto free;
196		}
197		i++;
198	}
199	kfree(v);
200	return 0;
201
202error:
203	if (ret == -ENOSYS)
204		dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n");
205	else if (ret)
206		dev_err(&dev->dev, "Xen PCI frontend error: %d!\n", ret);
207free:
208	kfree(v);
209	return ret;
210}
211
212static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq,
213		struct msi_msg *msg)
214{
215	/*
216	 * We set vector == 0 to tell the hypervisor we don't care about
217	 * it, but we want a pirq setup instead.  We use the dest_id fields
218	 * to pass the pirq that we want.
219	 */
220	memset(msg, 0, sizeof(*msg));
221	msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
222	msg->arch_addr_hi.destid_8_31 = pirq >> 8;
223	msg->arch_addr_lo.destid_0_7 = pirq & 0xFF;
224	msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
225	msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_EXTINT;
226}
227
228static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
229{
230	int irq, pirq;
231	struct msi_desc *msidesc;
232	struct msi_msg msg;
233
234	if (type == PCI_CAP_ID_MSI && nvec > 1)
235		return 1;
236
237	for_each_pci_msi_entry(msidesc, dev) {
238		pirq = xen_allocate_pirq_msi(dev, msidesc);
239		if (pirq < 0) {
240			irq = -ENODEV;
241			goto error;
242		}
243		xen_msi_compose_msg(dev, pirq, &msg);
244		__pci_write_msi_msg(msidesc, &msg);
245		dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq);
246		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq,
247					       (type == PCI_CAP_ID_MSI) ? nvec : 1,
248					       (type == PCI_CAP_ID_MSIX) ?
249					       "msi-x" : "msi",
250					       DOMID_SELF);
251		if (irq < 0)
252			goto error;
253		dev_dbg(&dev->dev,
254			"xen: msi --> pirq=%d --> irq=%d\n", pirq, irq);
255	}
256	return 0;
257
258error:
259	dev_err(&dev->dev, "Failed to create MSI%s! ret=%d!\n",
260		type == PCI_CAP_ID_MSI ? "" : "-X", irq);
261	return irq;
262}
263
264#ifdef CONFIG_XEN_DOM0
265static bool __read_mostly pci_seg_supported = true;
266
267static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
268{
269	int ret = 0;
270	struct msi_desc *msidesc;
271
272	for_each_pci_msi_entry(msidesc, dev) {
273		struct physdev_map_pirq map_irq;
274		domid_t domid;
275
276		domid = ret = xen_find_device_domain_owner(dev);
277		/* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED,
278		 * hence check ret value for < 0. */
279		if (ret < 0)
280			domid = DOMID_SELF;
281
282		memset(&map_irq, 0, sizeof(map_irq));
283		map_irq.domid = domid;
284		map_irq.type = MAP_PIRQ_TYPE_MSI_SEG;
285		map_irq.index = -1;
286		map_irq.pirq = -1;
287		map_irq.bus = dev->bus->number |
288			      (pci_domain_nr(dev->bus) << 16);
289		map_irq.devfn = dev->devfn;
290
291		if (type == PCI_CAP_ID_MSI && nvec > 1) {
292			map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI;
293			map_irq.entry_nr = nvec;
294		} else if (type == PCI_CAP_ID_MSIX) {
295			int pos;
296			unsigned long flags;
297			u32 table_offset, bir;
298
299			pos = dev->msix_cap;
300			pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
301					      &table_offset);
302			bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
303			flags = pci_resource_flags(dev, bir);
304			if (!flags || (flags & IORESOURCE_UNSET))
305				return -EINVAL;
306
307			map_irq.table_base = pci_resource_start(dev, bir);
308			map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
309		}
310
311		ret = -EINVAL;
312		if (pci_seg_supported)
313			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
314						    &map_irq);
315		if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) {
316			/*
317			 * If MAP_PIRQ_TYPE_MULTI_MSI is not available
318			 * there's nothing else we can do in this case.
319			 * Just set ret > 0 so driver can retry with
320			 * single MSI.
321			 */
322			ret = 1;
323			goto out;
324		}
325		if (ret == -EINVAL && !pci_domain_nr(dev->bus)) {
326			map_irq.type = MAP_PIRQ_TYPE_MSI;
327			map_irq.index = -1;
328			map_irq.pirq = -1;
329			map_irq.bus = dev->bus->number;
330			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
331						    &map_irq);
332			if (ret != -EINVAL)
333				pci_seg_supported = false;
334		}
335		if (ret) {
336			dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
337				 ret, domid);
338			goto out;
339		}
340
341		ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq,
342		                               (type == PCI_CAP_ID_MSI) ? nvec : 1,
343		                               (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi",
344		                               domid);
345		if (ret < 0)
346			goto out;
347	}
348	ret = 0;
349out:
350	return ret;
351}
352
353static void xen_initdom_restore_msi_irqs(struct pci_dev *dev)
354{
355	int ret = 0;
356
 
 
 
357	if (pci_seg_supported) {
358		struct physdev_pci_device restore_ext;
359
360		restore_ext.seg = pci_domain_nr(dev->bus);
361		restore_ext.bus = dev->bus->number;
362		restore_ext.devfn = dev->devfn;
363		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext,
364					&restore_ext);
365		if (ret == -ENOSYS)
366			pci_seg_supported = false;
367		WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret);
368	}
369	if (!pci_seg_supported) {
370		struct physdev_restore_msi restore;
371
372		restore.bus = dev->bus->number;
373		restore.devfn = dev->devfn;
374		ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore);
375		WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret);
376	}
 
377}
378#else /* CONFIG_XEN_DOM0 */
379#define xen_initdom_setup_msi_irqs	NULL
380#define xen_initdom_restore_msi_irqs	NULL
381#endif /* !CONFIG_XEN_DOM0 */
382
383static void xen_teardown_msi_irqs(struct pci_dev *dev)
384{
385	struct msi_desc *msidesc;
386	int i;
387
388	for_each_pci_msi_entry(msidesc, dev) {
389		if (msidesc->irq) {
390			for (i = 0; i < msidesc->nvec_used; i++)
391				xen_destroy_irq(msidesc->irq + i);
392		}
393	}
394}
395
396static void xen_pv_teardown_msi_irqs(struct pci_dev *dev)
397{
398	struct msi_desc *msidesc = first_pci_msi_entry(dev);
399
400	if (msidesc->msi_attrib.is_msix)
401		xen_pci_frontend_disable_msix(dev);
402	else
403		xen_pci_frontend_disable_msi(dev);
404
405	xen_teardown_msi_irqs(dev);
406}
407
408static int xen_msi_domain_alloc_irqs(struct irq_domain *domain,
409				     struct device *dev,  int nvec)
410{
411	int type;
412
413	if (WARN_ON_ONCE(!dev_is_pci(dev)))
414		return -EINVAL;
415
416	if (first_msi_entry(dev)->msi_attrib.is_msix)
417		type = PCI_CAP_ID_MSIX;
418	else
419		type = 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	.ops			= &xen_pci_msi_domain_ops,
440};
441
442/*
443 * This irq domain is a blatant violation of the irq domain design, but
444 * distangling XEN into real irq domains is not a job for mere mortals with
445 * limited XENology. But it's the least dangerous way for a mere mortal to
446 * get rid of the arch_*_msi_irqs() hackery in order to store the irq
447 * domain pointer in struct device. This irq domain wrappery allows to do
448 * that without breaking XEN terminally.
449 */
450static __init struct irq_domain *xen_create_pci_msi_domain(void)
451{
452	struct irq_domain *d = NULL;
453	struct fwnode_handle *fn;
454
455	fn = irq_domain_alloc_named_fwnode("XEN-MSI");
456	if (fn)
457		d = msi_create_irq_domain(fn, &xen_pci_msi_domain_info, NULL);
458
459	/* FIXME: No idea how to survive if this fails */
460	BUG_ON(!d);
461
462	return d;
463}
464
465static __init void xen_setup_pci_msi(void)
466{
467	if (xen_pv_domain()) {
468		if (xen_initial_domain()) {
469			xen_msi_ops.setup_msi_irqs = xen_initdom_setup_msi_irqs;
470			x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
471		} else {
472			xen_msi_ops.setup_msi_irqs = xen_setup_msi_irqs;
473		}
474		xen_msi_ops.teardown_msi_irqs = xen_pv_teardown_msi_irqs;
475		pci_msi_ignore_mask = 1;
476	} else if (xen_hvm_domain()) {
477		xen_msi_ops.setup_msi_irqs = xen_hvm_setup_msi_irqs;
478		xen_msi_ops.teardown_msi_irqs = xen_teardown_msi_irqs;
479	} else {
480		WARN_ON_ONCE(1);
481		return;
482	}
483
484	/*
485	 * Override the PCI/MSI irq domain init function. No point
486	 * in allocating the native domain and never use it.
487	 */
488	x86_init.irqs.create_pci_msi_domain = xen_create_pci_msi_domain;
 
 
 
 
 
489}
490
491#else /* CONFIG_PCI_MSI */
492static inline void xen_setup_pci_msi(void) { }
493#endif /* CONFIG_PCI_MSI */
494
495int __init pci_xen_init(void)
496{
497	if (!xen_pv_domain() || xen_initial_domain())
498		return -ENODEV;
499
500	printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
501
502	pcibios_set_cache_line_size();
503
504	pcibios_enable_irq = xen_pcifront_enable_irq;
505	pcibios_disable_irq = NULL;
506
507	/* Keep ACPI out of the picture */
508	acpi_noirq_set();
509
510	xen_setup_pci_msi();
511	return 0;
512}
513
514#ifdef CONFIG_PCI_MSI
515static void __init xen_hvm_msi_init(void)
516{
517	if (!disable_apic) {
518		/*
519		 * If hardware supports (x2)APIC virtualization (as indicated
520		 * by hypervisor's leaf 4) then we don't need to use pirqs/
521		 * event channels for MSI handling and instead use regular
522		 * APIC processing
523		 */
524		uint32_t eax = cpuid_eax(xen_cpuid_base() + 4);
525
526		if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) ||
527		    ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && boot_cpu_has(X86_FEATURE_APIC)))
528			return;
529	}
530	xen_setup_pci_msi();
531}
532#endif
533
534int __init pci_xen_hvm_init(void)
535{
536	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
537		return 0;
538
539#ifdef CONFIG_ACPI
540	/*
541	 * We don't want to change the actual ACPI delivery model,
542	 * just how GSIs get registered.
543	 */
544	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
545	__acpi_unregister_gsi = NULL;
546#endif
547
548#ifdef CONFIG_PCI_MSI
549	/*
550	 * We need to wait until after x2apic is initialized
551	 * before we can set MSI IRQ ops.
552	 */
553	x86_platform.apic_post_init = xen_hvm_msi_init;
554#endif
555	return 0;
556}
557
558#ifdef CONFIG_XEN_DOM0
559int __init pci_xen_initial_domain(void)
560{
561	int irq;
562
563	xen_setup_pci_msi();
564	__acpi_register_gsi = acpi_register_gsi_xen;
565	__acpi_unregister_gsi = NULL;
566	/*
567	 * Pre-allocate the legacy IRQs.  Use NR_LEGACY_IRQS here
568	 * because we don't have a PIC and thus nr_legacy_irqs() is zero.
569	 */
570	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
571		int trigger, polarity;
572
573		if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
574			continue;
575
576		xen_register_pirq(irq,
577			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
578			true /* Map GSI to PIRQ */);
579	}
580	if (0 == nr_ioapics) {
581		for (irq = 0; irq < nr_legacy_irqs(); irq++)
582			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
583	}
584	return 0;
585}
 
586
587struct xen_device_domain_owner {
588	domid_t domain;
589	struct pci_dev *dev;
590	struct list_head list;
591};
592
593static DEFINE_SPINLOCK(dev_domain_list_spinlock);
594static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list);
595
596static struct xen_device_domain_owner *find_device(struct pci_dev *dev)
597{
598	struct xen_device_domain_owner *owner;
599
600	list_for_each_entry(owner, &dev_domain_list, list) {
601		if (owner->dev == dev)
602			return owner;
603	}
604	return NULL;
605}
606
607int xen_find_device_domain_owner(struct pci_dev *dev)
608{
609	struct xen_device_domain_owner *owner;
610	int domain = -ENODEV;
611
612	spin_lock(&dev_domain_list_spinlock);
613	owner = find_device(dev);
614	if (owner)
615		domain = owner->domain;
616	spin_unlock(&dev_domain_list_spinlock);
617	return domain;
618}
619EXPORT_SYMBOL_GPL(xen_find_device_domain_owner);
620
621int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain)
622{
623	struct xen_device_domain_owner *owner;
624
625	owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL);
626	if (!owner)
627		return -ENODEV;
628
629	spin_lock(&dev_domain_list_spinlock);
630	if (find_device(dev)) {
631		spin_unlock(&dev_domain_list_spinlock);
632		kfree(owner);
633		return -EEXIST;
634	}
635	owner->domain = domain;
636	owner->dev = dev;
637	list_add_tail(&owner->list, &dev_domain_list);
638	spin_unlock(&dev_domain_list_spinlock);
639	return 0;
640}
641EXPORT_SYMBOL_GPL(xen_register_device_domain_owner);
642
643int xen_unregister_device_domain_owner(struct pci_dev *dev)
644{
645	struct xen_device_domain_owner *owner;
646
647	spin_lock(&dev_domain_list_spinlock);
648	owner = find_device(dev);
649	if (!owner) {
650		spin_unlock(&dev_domain_list_spinlock);
651		return -ENODEV;
652	}
653	list_del(&owner->list);
654	spin_unlock(&dev_domain_list_spinlock);
655	kfree(owner);
656	return 0;
657}
658EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner);
659#endif