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