xref: /openbmc/linux/drivers/pci/controller/vmd.c (revision 738f6ba1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Volume Management Device driver
4  * Copyright (c) 2015, Intel Corporation.
5  */
6 
7 #include <linux/device.h>
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/msi.h>
13 #include <linux/pci.h>
14 #include <linux/pci-ecam.h>
15 #include <linux/srcu.h>
16 #include <linux/rculist.h>
17 #include <linux/rcupdate.h>
18 
19 #include <asm/irqdomain.h>
20 #include <asm/device.h>
21 #include <asm/msi.h>
22 
23 #define VMD_CFGBAR	0
24 #define VMD_MEMBAR1	2
25 #define VMD_MEMBAR2	4
26 
27 #define PCI_REG_VMCAP		0x40
28 #define BUS_RESTRICT_CAP(vmcap)	(vmcap & 0x1)
29 #define PCI_REG_VMCONFIG	0x44
30 #define BUS_RESTRICT_CFG(vmcfg)	((vmcfg >> 8) & 0x3)
31 #define PCI_REG_VMLOCK		0x70
32 #define MB2_SHADOW_EN(vmlock)	(vmlock & 0x2)
33 
34 #define MB2_SHADOW_OFFSET	0x2000
35 #define MB2_SHADOW_SIZE		16
36 
37 enum vmd_features {
38 	/*
39 	 * Device may contain registers which hint the physical location of the
40 	 * membars, in order to allow proper address translation during
41 	 * resource assignment to enable guest virtualization
42 	 */
43 	VMD_FEAT_HAS_MEMBAR_SHADOW		= (1 << 0),
44 
45 	/*
46 	 * Device may provide root port configuration information which limits
47 	 * bus numbering
48 	 */
49 	VMD_FEAT_HAS_BUS_RESTRICTIONS		= (1 << 1),
50 
51 	/*
52 	 * Device contains physical location shadow registers in
53 	 * vendor-specific capability space
54 	 */
55 	VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP	= (1 << 2),
56 
57 	/*
58 	 * Device may use MSI-X vector 0 for software triggering and will not
59 	 * be used for MSI remapping
60 	 */
61 	VMD_FEAT_OFFSET_FIRST_VECTOR		= (1 << 3),
62 };
63 
64 /*
65  * Lock for manipulating VMD IRQ lists.
66  */
67 static DEFINE_RAW_SPINLOCK(list_lock);
68 
69 /**
70  * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
71  * @node:	list item for parent traversal.
72  * @irq:	back pointer to parent.
73  * @enabled:	true if driver enabled IRQ
74  * @virq:	the virtual IRQ value provided to the requesting driver.
75  *
76  * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
77  * a VMD IRQ using this structure.
78  */
79 struct vmd_irq {
80 	struct list_head	node;
81 	struct vmd_irq_list	*irq;
82 	bool			enabled;
83 	unsigned int		virq;
84 };
85 
86 /**
87  * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
88  * @irq_list:	the list of irq's the VMD one demuxes to.
89  * @srcu:	SRCU struct for local synchronization.
90  * @count:	number of child IRQs assigned to this vector; used to track
91  *		sharing.
92  */
93 struct vmd_irq_list {
94 	struct list_head	irq_list;
95 	struct srcu_struct	srcu;
96 	unsigned int		count;
97 };
98 
99 struct vmd_dev {
100 	struct pci_dev		*dev;
101 
102 	spinlock_t		cfg_lock;
103 	void __iomem		*cfgbar;
104 
105 	int msix_count;
106 	struct vmd_irq_list	*irqs;
107 
108 	struct pci_sysdata	sysdata;
109 	struct resource		resources[3];
110 	struct irq_domain	*irq_domain;
111 	struct pci_bus		*bus;
112 	u8			busn_start;
113 	u8			first_vec;
114 };
115 
116 static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
117 {
118 	return container_of(bus->sysdata, struct vmd_dev, sysdata);
119 }
120 
121 static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
122 					   struct vmd_irq_list *irqs)
123 {
124 	return irqs - vmd->irqs;
125 }
126 
127 /*
128  * Drivers managing a device in a VMD domain allocate their own IRQs as before,
129  * but the MSI entry for the hardware it's driving will be programmed with a
130  * destination ID for the VMD MSI-X table.  The VMD muxes interrupts in its
131  * domain into one of its own, and the VMD driver de-muxes these for the
132  * handlers sharing that VMD IRQ.  The vmd irq_domain provides the operations
133  * and irq_chip to set this up.
134  */
135 static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
136 {
137 	struct vmd_irq *vmdirq = data->chip_data;
138 	struct vmd_irq_list *irq = vmdirq->irq;
139 	struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
140 
141 	memset(msg, 0, sizeof(*msg));
142 	msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
143 	msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
144 	msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq);
145 }
146 
147 /*
148  * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
149  */
150 static void vmd_irq_enable(struct irq_data *data)
151 {
152 	struct vmd_irq *vmdirq = data->chip_data;
153 	unsigned long flags;
154 
155 	raw_spin_lock_irqsave(&list_lock, flags);
156 	WARN_ON(vmdirq->enabled);
157 	list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
158 	vmdirq->enabled = true;
159 	raw_spin_unlock_irqrestore(&list_lock, flags);
160 
161 	data->chip->irq_unmask(data);
162 }
163 
164 static void vmd_irq_disable(struct irq_data *data)
165 {
166 	struct vmd_irq *vmdirq = data->chip_data;
167 	unsigned long flags;
168 
169 	data->chip->irq_mask(data);
170 
171 	raw_spin_lock_irqsave(&list_lock, flags);
172 	if (vmdirq->enabled) {
173 		list_del_rcu(&vmdirq->node);
174 		vmdirq->enabled = false;
175 	}
176 	raw_spin_unlock_irqrestore(&list_lock, flags);
177 }
178 
179 /*
180  * XXX: Stubbed until we develop acceptable way to not create conflicts with
181  * other devices sharing the same vector.
182  */
183 static int vmd_irq_set_affinity(struct irq_data *data,
184 				const struct cpumask *dest, bool force)
185 {
186 	return -EINVAL;
187 }
188 
189 static struct irq_chip vmd_msi_controller = {
190 	.name			= "VMD-MSI",
191 	.irq_enable		= vmd_irq_enable,
192 	.irq_disable		= vmd_irq_disable,
193 	.irq_compose_msi_msg	= vmd_compose_msi_msg,
194 	.irq_set_affinity	= vmd_irq_set_affinity,
195 };
196 
197 static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
198 				     msi_alloc_info_t *arg)
199 {
200 	return 0;
201 }
202 
203 /*
204  * XXX: We can be even smarter selecting the best IRQ once we solve the
205  * affinity problem.
206  */
207 static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
208 {
209 	unsigned long flags;
210 	int i, best;
211 
212 	if (vmd->msix_count == 1 + vmd->first_vec)
213 		return &vmd->irqs[vmd->first_vec];
214 
215 	/*
216 	 * White list for fast-interrupt handlers. All others will share the
217 	 * "slow" interrupt vector.
218 	 */
219 	switch (msi_desc_to_pci_dev(desc)->class) {
220 	case PCI_CLASS_STORAGE_EXPRESS:
221 		break;
222 	default:
223 		return &vmd->irqs[vmd->first_vec];
224 	}
225 
226 	raw_spin_lock_irqsave(&list_lock, flags);
227 	best = vmd->first_vec + 1;
228 	for (i = best; i < vmd->msix_count; i++)
229 		if (vmd->irqs[i].count < vmd->irqs[best].count)
230 			best = i;
231 	vmd->irqs[best].count++;
232 	raw_spin_unlock_irqrestore(&list_lock, flags);
233 
234 	return &vmd->irqs[best];
235 }
236 
237 static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
238 			unsigned int virq, irq_hw_number_t hwirq,
239 			msi_alloc_info_t *arg)
240 {
241 	struct msi_desc *desc = arg->desc;
242 	struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
243 	struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
244 	unsigned int index, vector;
245 
246 	if (!vmdirq)
247 		return -ENOMEM;
248 
249 	INIT_LIST_HEAD(&vmdirq->node);
250 	vmdirq->irq = vmd_next_irq(vmd, desc);
251 	vmdirq->virq = virq;
252 	index = index_from_irqs(vmd, vmdirq->irq);
253 	vector = pci_irq_vector(vmd->dev, index);
254 
255 	irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
256 			    handle_untracked_irq, vmd, NULL);
257 	return 0;
258 }
259 
260 static void vmd_msi_free(struct irq_domain *domain,
261 			struct msi_domain_info *info, unsigned int virq)
262 {
263 	struct vmd_irq *vmdirq = irq_get_chip_data(virq);
264 	unsigned long flags;
265 
266 	synchronize_srcu(&vmdirq->irq->srcu);
267 
268 	/* XXX: Potential optimization to rebalance */
269 	raw_spin_lock_irqsave(&list_lock, flags);
270 	vmdirq->irq->count--;
271 	raw_spin_unlock_irqrestore(&list_lock, flags);
272 
273 	kfree(vmdirq);
274 }
275 
276 static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
277 			   int nvec, msi_alloc_info_t *arg)
278 {
279 	struct pci_dev *pdev = to_pci_dev(dev);
280 	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
281 
282 	if (nvec > vmd->msix_count)
283 		return vmd->msix_count;
284 
285 	memset(arg, 0, sizeof(*arg));
286 	return 0;
287 }
288 
289 static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
290 {
291 	arg->desc = desc;
292 }
293 
294 static struct msi_domain_ops vmd_msi_domain_ops = {
295 	.get_hwirq	= vmd_get_hwirq,
296 	.msi_init	= vmd_msi_init,
297 	.msi_free	= vmd_msi_free,
298 	.msi_prepare	= vmd_msi_prepare,
299 	.set_desc	= vmd_set_desc,
300 };
301 
302 static struct msi_domain_info vmd_msi_domain_info = {
303 	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
304 			  MSI_FLAG_PCI_MSIX,
305 	.ops		= &vmd_msi_domain_ops,
306 	.chip		= &vmd_msi_controller,
307 };
308 
309 static int vmd_create_irq_domain(struct vmd_dev *vmd)
310 {
311 	struct fwnode_handle *fn;
312 
313 	fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
314 	if (!fn)
315 		return -ENODEV;
316 
317 	vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL);
318 	if (!vmd->irq_domain) {
319 		irq_domain_free_fwnode(fn);
320 		return -ENODEV;
321 	}
322 
323 	return 0;
324 }
325 
326 static void vmd_remove_irq_domain(struct vmd_dev *vmd)
327 {
328 	if (vmd->irq_domain) {
329 		struct fwnode_handle *fn = vmd->irq_domain->fwnode;
330 
331 		irq_domain_remove(vmd->irq_domain);
332 		irq_domain_free_fwnode(fn);
333 	}
334 }
335 
336 static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
337 				  unsigned int devfn, int reg, int len)
338 {
339 	unsigned int busnr_ecam = bus->number - vmd->busn_start;
340 	u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
341 
342 	if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR]))
343 		return NULL;
344 
345 	return vmd->cfgbar + offset;
346 }
347 
348 /*
349  * CPU may deadlock if config space is not serialized on some versions of this
350  * hardware, so all config space access is done under a spinlock.
351  */
352 static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
353 			int len, u32 *value)
354 {
355 	struct vmd_dev *vmd = vmd_from_bus(bus);
356 	void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
357 	unsigned long flags;
358 	int ret = 0;
359 
360 	if (!addr)
361 		return -EFAULT;
362 
363 	spin_lock_irqsave(&vmd->cfg_lock, flags);
364 	switch (len) {
365 	case 1:
366 		*value = readb(addr);
367 		break;
368 	case 2:
369 		*value = readw(addr);
370 		break;
371 	case 4:
372 		*value = readl(addr);
373 		break;
374 	default:
375 		ret = -EINVAL;
376 		break;
377 	}
378 	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
379 	return ret;
380 }
381 
382 /*
383  * VMD h/w converts non-posted config writes to posted memory writes. The
384  * read-back in this function forces the completion so it returns only after
385  * the config space was written, as expected.
386  */
387 static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
388 			 int len, u32 value)
389 {
390 	struct vmd_dev *vmd = vmd_from_bus(bus);
391 	void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
392 	unsigned long flags;
393 	int ret = 0;
394 
395 	if (!addr)
396 		return -EFAULT;
397 
398 	spin_lock_irqsave(&vmd->cfg_lock, flags);
399 	switch (len) {
400 	case 1:
401 		writeb(value, addr);
402 		readb(addr);
403 		break;
404 	case 2:
405 		writew(value, addr);
406 		readw(addr);
407 		break;
408 	case 4:
409 		writel(value, addr);
410 		readl(addr);
411 		break;
412 	default:
413 		ret = -EINVAL;
414 		break;
415 	}
416 	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
417 	return ret;
418 }
419 
420 static struct pci_ops vmd_ops = {
421 	.read		= vmd_pci_read,
422 	.write		= vmd_pci_write,
423 };
424 
425 static void vmd_attach_resources(struct vmd_dev *vmd)
426 {
427 	vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
428 	vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
429 }
430 
431 static void vmd_detach_resources(struct vmd_dev *vmd)
432 {
433 	vmd->dev->resource[VMD_MEMBAR1].child = NULL;
434 	vmd->dev->resource[VMD_MEMBAR2].child = NULL;
435 }
436 
437 /*
438  * VMD domains start at 0x10000 to not clash with ACPI _SEG domains.
439  * Per ACPI r6.0, sec 6.5.6,  _SEG returns an integer, of which the lower
440  * 16 bits are the PCI Segment Group (domain) number.  Other bits are
441  * currently reserved.
442  */
443 static int vmd_find_free_domain(void)
444 {
445 	int domain = 0xffff;
446 	struct pci_bus *bus = NULL;
447 
448 	while ((bus = pci_find_next_bus(bus)) != NULL)
449 		domain = max_t(int, domain, pci_domain_nr(bus));
450 	return domain + 1;
451 }
452 
453 static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
454 				resource_size_t *offset1,
455 				resource_size_t *offset2)
456 {
457 	struct pci_dev *dev = vmd->dev;
458 	u64 phys1, phys2;
459 
460 	if (native_hint) {
461 		u32 vmlock;
462 		int ret;
463 
464 		ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
465 		if (ret || vmlock == ~0)
466 			return -ENODEV;
467 
468 		if (MB2_SHADOW_EN(vmlock)) {
469 			void __iomem *membar2;
470 
471 			membar2 = pci_iomap(dev, VMD_MEMBAR2, 0);
472 			if (!membar2)
473 				return -ENOMEM;
474 			phys1 = readq(membar2 + MB2_SHADOW_OFFSET);
475 			phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8);
476 			pci_iounmap(dev, membar2);
477 		} else
478 			return 0;
479 	} else {
480 		/* Hypervisor-Emulated Vendor-Specific Capability */
481 		int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
482 		u32 reg, regu;
483 
484 		pci_read_config_dword(dev, pos + 4, &reg);
485 
486 		/* "SHDW" */
487 		if (pos && reg == 0x53484457) {
488 			pci_read_config_dword(dev, pos + 8, &reg);
489 			pci_read_config_dword(dev, pos + 12, &regu);
490 			phys1 = (u64) regu << 32 | reg;
491 
492 			pci_read_config_dword(dev, pos + 16, &reg);
493 			pci_read_config_dword(dev, pos + 20, &regu);
494 			phys2 = (u64) regu << 32 | reg;
495 		} else
496 			return 0;
497 	}
498 
499 	*offset1 = dev->resource[VMD_MEMBAR1].start -
500 			(phys1 & PCI_BASE_ADDRESS_MEM_MASK);
501 	*offset2 = dev->resource[VMD_MEMBAR2].start -
502 			(phys2 & PCI_BASE_ADDRESS_MEM_MASK);
503 
504 	return 0;
505 }
506 
507 static int vmd_get_bus_number_start(struct vmd_dev *vmd)
508 {
509 	struct pci_dev *dev = vmd->dev;
510 	u16 reg;
511 
512 	pci_read_config_word(dev, PCI_REG_VMCAP, &reg);
513 	if (BUS_RESTRICT_CAP(reg)) {
514 		pci_read_config_word(dev, PCI_REG_VMCONFIG, &reg);
515 
516 		switch (BUS_RESTRICT_CFG(reg)) {
517 		case 0:
518 			vmd->busn_start = 0;
519 			break;
520 		case 1:
521 			vmd->busn_start = 128;
522 			break;
523 		case 2:
524 			vmd->busn_start = 224;
525 			break;
526 		default:
527 			pci_err(dev, "Unknown Bus Offset Setting (%d)\n",
528 				BUS_RESTRICT_CFG(reg));
529 			return -ENODEV;
530 		}
531 	}
532 
533 	return 0;
534 }
535 
536 static irqreturn_t vmd_irq(int irq, void *data)
537 {
538 	struct vmd_irq_list *irqs = data;
539 	struct vmd_irq *vmdirq;
540 	int idx;
541 
542 	idx = srcu_read_lock(&irqs->srcu);
543 	list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
544 		generic_handle_irq(vmdirq->virq);
545 	srcu_read_unlock(&irqs->srcu, idx);
546 
547 	return IRQ_HANDLED;
548 }
549 
550 static int vmd_alloc_irqs(struct vmd_dev *vmd)
551 {
552 	struct pci_dev *dev = vmd->dev;
553 	int i, err;
554 
555 	vmd->msix_count = pci_msix_vec_count(dev);
556 	if (vmd->msix_count < 0)
557 		return -ENODEV;
558 
559 	vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1,
560 						vmd->msix_count, PCI_IRQ_MSIX);
561 	if (vmd->msix_count < 0)
562 		return vmd->msix_count;
563 
564 	vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
565 				 GFP_KERNEL);
566 	if (!vmd->irqs)
567 		return -ENOMEM;
568 
569 	for (i = 0; i < vmd->msix_count; i++) {
570 		err = init_srcu_struct(&vmd->irqs[i].srcu);
571 		if (err)
572 			return err;
573 
574 		INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
575 		err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
576 				       vmd_irq, IRQF_NO_THREAD,
577 				       "vmd", &vmd->irqs[i]);
578 		if (err)
579 			return err;
580 	}
581 
582 	return 0;
583 }
584 
585 static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
586 {
587 	struct pci_sysdata *sd = &vmd->sysdata;
588 	struct resource *res;
589 	u32 upper_bits;
590 	unsigned long flags;
591 	LIST_HEAD(resources);
592 	resource_size_t offset[2] = {0};
593 	resource_size_t membar2_offset = 0x2000;
594 	struct pci_bus *child;
595 	int ret;
596 
597 	/*
598 	 * Shadow registers may exist in certain VMD device ids which allow
599 	 * guests to correctly assign host physical addresses to the root ports
600 	 * and child devices. These registers will either return the host value
601 	 * or 0, depending on an enable bit in the VMD device.
602 	 */
603 	if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
604 		membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
605 		ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]);
606 		if (ret)
607 			return ret;
608 	} else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
609 		ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]);
610 		if (ret)
611 			return ret;
612 	}
613 
614 	/*
615 	 * Certain VMD devices may have a root port configuration option which
616 	 * limits the bus range to between 0-127, 128-255, or 224-255
617 	 */
618 	if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {
619 		ret = vmd_get_bus_number_start(vmd);
620 		if (ret)
621 			return ret;
622 	}
623 
624 	res = &vmd->dev->resource[VMD_CFGBAR];
625 	vmd->resources[0] = (struct resource) {
626 		.name  = "VMD CFGBAR",
627 		.start = vmd->busn_start,
628 		.end   = vmd->busn_start + (resource_size(res) >> 20) - 1,
629 		.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
630 	};
631 
632 	/*
633 	 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
634 	 * put 32-bit resources in the window.
635 	 *
636 	 * There's no hardware reason why a 64-bit window *couldn't*
637 	 * contain a 32-bit resource, but pbus_size_mem() computes the
638 	 * bridge window size assuming a 64-bit window will contain no
639 	 * 32-bit resources.  __pci_assign_resource() enforces that
640 	 * artificial restriction to make sure everything will fit.
641 	 *
642 	 * The only way we could use a 64-bit non-prefetchable MEMBAR is
643 	 * if its address is <4GB so that we can convert it to a 32-bit
644 	 * resource.  To be visible to the host OS, all VMD endpoints must
645 	 * be initially configured by platform BIOS, which includes setting
646 	 * up these resources.  We can assume the device is configured
647 	 * according to the platform needs.
648 	 */
649 	res = &vmd->dev->resource[VMD_MEMBAR1];
650 	upper_bits = upper_32_bits(res->end);
651 	flags = res->flags & ~IORESOURCE_SIZEALIGN;
652 	if (!upper_bits)
653 		flags &= ~IORESOURCE_MEM_64;
654 	vmd->resources[1] = (struct resource) {
655 		.name  = "VMD MEMBAR1",
656 		.start = res->start,
657 		.end   = res->end,
658 		.flags = flags,
659 		.parent = res,
660 	};
661 
662 	res = &vmd->dev->resource[VMD_MEMBAR2];
663 	upper_bits = upper_32_bits(res->end);
664 	flags = res->flags & ~IORESOURCE_SIZEALIGN;
665 	if (!upper_bits)
666 		flags &= ~IORESOURCE_MEM_64;
667 	vmd->resources[2] = (struct resource) {
668 		.name  = "VMD MEMBAR2",
669 		.start = res->start + membar2_offset,
670 		.end   = res->end,
671 		.flags = flags,
672 		.parent = res,
673 	};
674 
675 	sd->vmd_dev = vmd->dev;
676 	sd->domain = vmd_find_free_domain();
677 	if (sd->domain < 0)
678 		return sd->domain;
679 
680 	sd->node = pcibus_to_node(vmd->dev->bus);
681 
682 	ret = vmd_create_irq_domain(vmd);
683 	if (ret)
684 		return ret;
685 
686 	/*
687 	 * Override the irq domain bus token so the domain can be distinguished
688 	 * from a regular PCI/MSI domain.
689 	 */
690 	irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI);
691 
692 	pci_add_resource(&resources, &vmd->resources[0]);
693 	pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);
694 	pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]);
695 
696 	vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start,
697 				       &vmd_ops, sd, &resources);
698 	if (!vmd->bus) {
699 		pci_free_resource_list(&resources);
700 		vmd_remove_irq_domain(vmd);
701 		return -ENODEV;
702 	}
703 
704 	vmd_attach_resources(vmd);
705 	if (vmd->irq_domain)
706 		dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
707 
708 	pci_scan_child_bus(vmd->bus);
709 	pci_assign_unassigned_bus_resources(vmd->bus);
710 
711 	/*
712 	 * VMD root buses are virtual and don't return true on pci_is_pcie()
713 	 * and will fail pcie_bus_configure_settings() early. It can instead be
714 	 * run on each of the real root ports.
715 	 */
716 	list_for_each_entry(child, &vmd->bus->children, node)
717 		pcie_bus_configure_settings(child);
718 
719 	pci_bus_add_devices(vmd->bus);
720 
721 	WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
722 			       "domain"), "Can't create symlink to domain\n");
723 	return 0;
724 }
725 
726 static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
727 {
728 	unsigned long features = (unsigned long) id->driver_data;
729 	struct vmd_dev *vmd;
730 	int err;
731 
732 	if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
733 		return -ENOMEM;
734 
735 	vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
736 	if (!vmd)
737 		return -ENOMEM;
738 
739 	vmd->dev = dev;
740 	err = pcim_enable_device(dev);
741 	if (err < 0)
742 		return err;
743 
744 	vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
745 	if (!vmd->cfgbar)
746 		return -ENOMEM;
747 
748 	pci_set_master(dev);
749 	if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
750 	    dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
751 		return -ENODEV;
752 
753 	if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
754 		vmd->first_vec = 1;
755 
756 	err = vmd_alloc_irqs(vmd);
757 	if (err)
758 		return err;
759 
760 	spin_lock_init(&vmd->cfg_lock);
761 	pci_set_drvdata(dev, vmd);
762 	err = vmd_enable_domain(vmd, features);
763 	if (err)
764 		return err;
765 
766 	dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
767 		 vmd->sysdata.domain);
768 	return 0;
769 }
770 
771 static void vmd_cleanup_srcu(struct vmd_dev *vmd)
772 {
773 	int i;
774 
775 	for (i = 0; i < vmd->msix_count; i++)
776 		cleanup_srcu_struct(&vmd->irqs[i].srcu);
777 }
778 
779 static void vmd_remove(struct pci_dev *dev)
780 {
781 	struct vmd_dev *vmd = pci_get_drvdata(dev);
782 
783 	sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
784 	pci_stop_root_bus(vmd->bus);
785 	pci_remove_root_bus(vmd->bus);
786 	vmd_cleanup_srcu(vmd);
787 	vmd_detach_resources(vmd);
788 	vmd_remove_irq_domain(vmd);
789 }
790 
791 #ifdef CONFIG_PM_SLEEP
792 static int vmd_suspend(struct device *dev)
793 {
794 	struct pci_dev *pdev = to_pci_dev(dev);
795 	struct vmd_dev *vmd = pci_get_drvdata(pdev);
796 	int i;
797 
798 	for (i = 0; i < vmd->msix_count; i++)
799 		devm_free_irq(dev, pci_irq_vector(pdev, i), &vmd->irqs[i]);
800 
801 	return 0;
802 }
803 
804 static int vmd_resume(struct device *dev)
805 {
806 	struct pci_dev *pdev = to_pci_dev(dev);
807 	struct vmd_dev *vmd = pci_get_drvdata(pdev);
808 	int err, i;
809 
810 	for (i = 0; i < vmd->msix_count; i++) {
811 		err = devm_request_irq(dev, pci_irq_vector(pdev, i),
812 				       vmd_irq, IRQF_NO_THREAD,
813 				       "vmd", &vmd->irqs[i]);
814 		if (err)
815 			return err;
816 	}
817 
818 	return 0;
819 }
820 #endif
821 static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
822 
823 static const struct pci_device_id vmd_ids[] = {
824 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_201D),
825 		.driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP,},
826 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0),
827 		.driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW |
828 				VMD_FEAT_HAS_BUS_RESTRICTIONS,},
829 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x467f),
830 		.driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
831 				VMD_FEAT_HAS_BUS_RESTRICTIONS |
832 				VMD_FEAT_OFFSET_FIRST_VECTOR,},
833 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x4c3d),
834 		.driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
835 				VMD_FEAT_HAS_BUS_RESTRICTIONS |
836 				VMD_FEAT_OFFSET_FIRST_VECTOR,},
837 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
838 		.driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
839 				VMD_FEAT_HAS_BUS_RESTRICTIONS |
840 				VMD_FEAT_OFFSET_FIRST_VECTOR,},
841 	{0,}
842 };
843 MODULE_DEVICE_TABLE(pci, vmd_ids);
844 
845 static struct pci_driver vmd_drv = {
846 	.name		= "vmd",
847 	.id_table	= vmd_ids,
848 	.probe		= vmd_probe,
849 	.remove		= vmd_remove,
850 	.driver		= {
851 		.pm	= &vmd_dev_pm_ops,
852 	},
853 };
854 module_pci_driver(vmd_drv);
855 
856 MODULE_AUTHOR("Intel Corporation");
857 MODULE_LICENSE("GPL v2");
858 MODULE_VERSION("0.6");
859