Loading...
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
37enum 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/*
53 * Lock for manipulating VMD IRQ lists.
54 */
55static DEFINE_RAW_SPINLOCK(list_lock);
56
57/**
58 * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
59 * @node: list item for parent traversal.
60 * @irq: back pointer to parent.
61 * @enabled: true if driver enabled IRQ
62 * @virq: the virtual IRQ value provided to the requesting driver.
63 *
64 * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
65 * a VMD IRQ using this structure.
66 */
67struct vmd_irq {
68 struct list_head node;
69 struct vmd_irq_list *irq;
70 bool enabled;
71 unsigned int virq;
72};
73
74/**
75 * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
76 * @irq_list: the list of irq's the VMD one demuxes to.
77 * @srcu: SRCU struct for local synchronization.
78 * @count: number of child IRQs assigned to this vector; used to track
79 * sharing.
80 */
81struct vmd_irq_list {
82 struct list_head irq_list;
83 struct srcu_struct srcu;
84 unsigned int count;
85};
86
87struct vmd_dev {
88 struct pci_dev *dev;
89
90 spinlock_t cfg_lock;
91 char __iomem *cfgbar;
92
93 int msix_count;
94 struct vmd_irq_list *irqs;
95
96 struct pci_sysdata sysdata;
97 struct resource resources[3];
98 struct irq_domain *irq_domain;
99 struct pci_bus *bus;
100 u8 busn_start;
101
102 struct dma_map_ops dma_ops;
103 struct dma_domain dma_domain;
104};
105
106static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
107{
108 return container_of(bus->sysdata, struct vmd_dev, sysdata);
109}
110
111static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
112 struct vmd_irq_list *irqs)
113{
114 return irqs - vmd->irqs;
115}
116
117/*
118 * Drivers managing a device in a VMD domain allocate their own IRQs as before,
119 * but the MSI entry for the hardware it's driving will be programmed with a
120 * destination ID for the VMD MSI-X table. The VMD muxes interrupts in its
121 * domain into one of its own, and the VMD driver de-muxes these for the
122 * handlers sharing that VMD IRQ. The vmd irq_domain provides the operations
123 * and irq_chip to set this up.
124 */
125static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
126{
127 struct vmd_irq *vmdirq = data->chip_data;
128 struct vmd_irq_list *irq = vmdirq->irq;
129 struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
130
131 msg->address_hi = MSI_ADDR_BASE_HI;
132 msg->address_lo = MSI_ADDR_BASE_LO |
133 MSI_ADDR_DEST_ID(index_from_irqs(vmd, irq));
134 msg->data = 0;
135}
136
137/*
138 * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
139 */
140static void vmd_irq_enable(struct irq_data *data)
141{
142 struct vmd_irq *vmdirq = data->chip_data;
143 unsigned long flags;
144
145 raw_spin_lock_irqsave(&list_lock, flags);
146 WARN_ON(vmdirq->enabled);
147 list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
148 vmdirq->enabled = true;
149 raw_spin_unlock_irqrestore(&list_lock, flags);
150
151 data->chip->irq_unmask(data);
152}
153
154static void vmd_irq_disable(struct irq_data *data)
155{
156 struct vmd_irq *vmdirq = data->chip_data;
157 unsigned long flags;
158
159 data->chip->irq_mask(data);
160
161 raw_spin_lock_irqsave(&list_lock, flags);
162 if (vmdirq->enabled) {
163 list_del_rcu(&vmdirq->node);
164 vmdirq->enabled = false;
165 }
166 raw_spin_unlock_irqrestore(&list_lock, flags);
167}
168
169/*
170 * XXX: Stubbed until we develop acceptable way to not create conflicts with
171 * other devices sharing the same vector.
172 */
173static int vmd_irq_set_affinity(struct irq_data *data,
174 const struct cpumask *dest, bool force)
175{
176 return -EINVAL;
177}
178
179static struct irq_chip vmd_msi_controller = {
180 .name = "VMD-MSI",
181 .irq_enable = vmd_irq_enable,
182 .irq_disable = vmd_irq_disable,
183 .irq_compose_msi_msg = vmd_compose_msi_msg,
184 .irq_set_affinity = vmd_irq_set_affinity,
185};
186
187static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
188 msi_alloc_info_t *arg)
189{
190 return 0;
191}
192
193/*
194 * XXX: We can be even smarter selecting the best IRQ once we solve the
195 * affinity problem.
196 */
197static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
198{
199 int i, best = 1;
200 unsigned long flags;
201
202 if (vmd->msix_count == 1)
203 return &vmd->irqs[0];
204
205 /*
206 * White list for fast-interrupt handlers. All others will share the
207 * "slow" interrupt vector.
208 */
209 switch (msi_desc_to_pci_dev(desc)->class) {
210 case PCI_CLASS_STORAGE_EXPRESS:
211 break;
212 default:
213 return &vmd->irqs[0];
214 }
215
216 raw_spin_lock_irqsave(&list_lock, flags);
217 for (i = 1; i < vmd->msix_count; i++)
218 if (vmd->irqs[i].count < vmd->irqs[best].count)
219 best = i;
220 vmd->irqs[best].count++;
221 raw_spin_unlock_irqrestore(&list_lock, flags);
222
223 return &vmd->irqs[best];
224}
225
226static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
227 unsigned int virq, irq_hw_number_t hwirq,
228 msi_alloc_info_t *arg)
229{
230 struct msi_desc *desc = arg->desc;
231 struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
232 struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
233 unsigned int index, vector;
234
235 if (!vmdirq)
236 return -ENOMEM;
237
238 INIT_LIST_HEAD(&vmdirq->node);
239 vmdirq->irq = vmd_next_irq(vmd, desc);
240 vmdirq->virq = virq;
241 index = index_from_irqs(vmd, vmdirq->irq);
242 vector = pci_irq_vector(vmd->dev, index);
243
244 irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
245 handle_untracked_irq, vmd, NULL);
246 return 0;
247}
248
249static void vmd_msi_free(struct irq_domain *domain,
250 struct msi_domain_info *info, unsigned int virq)
251{
252 struct vmd_irq *vmdirq = irq_get_chip_data(virq);
253 unsigned long flags;
254
255 synchronize_srcu(&vmdirq->irq->srcu);
256
257 /* XXX: Potential optimization to rebalance */
258 raw_spin_lock_irqsave(&list_lock, flags);
259 vmdirq->irq->count--;
260 raw_spin_unlock_irqrestore(&list_lock, flags);
261
262 kfree(vmdirq);
263}
264
265static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
266 int nvec, msi_alloc_info_t *arg)
267{
268 struct pci_dev *pdev = to_pci_dev(dev);
269 struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
270
271 if (nvec > vmd->msix_count)
272 return vmd->msix_count;
273
274 memset(arg, 0, sizeof(*arg));
275 return 0;
276}
277
278static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
279{
280 arg->desc = desc;
281}
282
283static struct msi_domain_ops vmd_msi_domain_ops = {
284 .get_hwirq = vmd_get_hwirq,
285 .msi_init = vmd_msi_init,
286 .msi_free = vmd_msi_free,
287 .msi_prepare = vmd_msi_prepare,
288 .set_desc = vmd_set_desc,
289};
290
291static struct msi_domain_info vmd_msi_domain_info = {
292 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
293 MSI_FLAG_PCI_MSIX,
294 .ops = &vmd_msi_domain_ops,
295 .chip = &vmd_msi_controller,
296};
297
298/*
299 * VMD replaces the requester ID with its own. DMA mappings for devices in a
300 * VMD domain need to be mapped for the VMD, not the device requiring
301 * the mapping.
302 */
303static struct device *to_vmd_dev(struct device *dev)
304{
305 struct pci_dev *pdev = to_pci_dev(dev);
306 struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
307
308 return &vmd->dev->dev;
309}
310
311static void *vmd_alloc(struct device *dev, size_t size, dma_addr_t *addr,
312 gfp_t flag, unsigned long attrs)
313{
314 return dma_alloc_attrs(to_vmd_dev(dev), size, addr, flag, attrs);
315}
316
317static void vmd_free(struct device *dev, size_t size, void *vaddr,
318 dma_addr_t addr, unsigned long attrs)
319{
320 return dma_free_attrs(to_vmd_dev(dev), size, vaddr, addr, attrs);
321}
322
323static int vmd_mmap(struct device *dev, struct vm_area_struct *vma,
324 void *cpu_addr, dma_addr_t addr, size_t size,
325 unsigned long attrs)
326{
327 return dma_mmap_attrs(to_vmd_dev(dev), vma, cpu_addr, addr, size,
328 attrs);
329}
330
331static int vmd_get_sgtable(struct device *dev, struct sg_table *sgt,
332 void *cpu_addr, dma_addr_t addr, size_t size,
333 unsigned long attrs)
334{
335 return dma_get_sgtable_attrs(to_vmd_dev(dev), sgt, cpu_addr, addr, size,
336 attrs);
337}
338
339static dma_addr_t vmd_map_page(struct device *dev, struct page *page,
340 unsigned long offset, size_t size,
341 enum dma_data_direction dir,
342 unsigned long attrs)
343{
344 return dma_map_page_attrs(to_vmd_dev(dev), page, offset, size, dir,
345 attrs);
346}
347
348static void vmd_unmap_page(struct device *dev, dma_addr_t addr, size_t size,
349 enum dma_data_direction dir, unsigned long attrs)
350{
351 dma_unmap_page_attrs(to_vmd_dev(dev), addr, size, dir, attrs);
352}
353
354static int vmd_map_sg(struct device *dev, struct scatterlist *sg, int nents,
355 enum dma_data_direction dir, unsigned long attrs)
356{
357 return dma_map_sg_attrs(to_vmd_dev(dev), sg, nents, dir, attrs);
358}
359
360static void vmd_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
361 enum dma_data_direction dir, unsigned long attrs)
362{
363 dma_unmap_sg_attrs(to_vmd_dev(dev), sg, nents, dir, attrs);
364}
365
366static void vmd_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
367 size_t size, enum dma_data_direction dir)
368{
369 dma_sync_single_for_cpu(to_vmd_dev(dev), addr, size, dir);
370}
371
372static void vmd_sync_single_for_device(struct device *dev, dma_addr_t addr,
373 size_t size, enum dma_data_direction dir)
374{
375 dma_sync_single_for_device(to_vmd_dev(dev), addr, size, dir);
376}
377
378static void vmd_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
379 int nents, enum dma_data_direction dir)
380{
381 dma_sync_sg_for_cpu(to_vmd_dev(dev), sg, nents, dir);
382}
383
384static void vmd_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
385 int nents, enum dma_data_direction dir)
386{
387 dma_sync_sg_for_device(to_vmd_dev(dev), sg, nents, dir);
388}
389
390static int vmd_dma_supported(struct device *dev, u64 mask)
391{
392 return dma_supported(to_vmd_dev(dev), mask);
393}
394
395static u64 vmd_get_required_mask(struct device *dev)
396{
397 return dma_get_required_mask(to_vmd_dev(dev));
398}
399
400static void vmd_teardown_dma_ops(struct vmd_dev *vmd)
401{
402 struct dma_domain *domain = &vmd->dma_domain;
403
404 if (get_dma_ops(&vmd->dev->dev))
405 del_dma_domain(domain);
406}
407
408#define ASSIGN_VMD_DMA_OPS(source, dest, fn) \
409 do { \
410 if (source->fn) \
411 dest->fn = vmd_##fn; \
412 } while (0)
413
414static void vmd_setup_dma_ops(struct vmd_dev *vmd)
415{
416 const struct dma_map_ops *source = get_dma_ops(&vmd->dev->dev);
417 struct dma_map_ops *dest = &vmd->dma_ops;
418 struct dma_domain *domain = &vmd->dma_domain;
419
420 domain->domain_nr = vmd->sysdata.domain;
421 domain->dma_ops = dest;
422
423 if (!source)
424 return;
425 ASSIGN_VMD_DMA_OPS(source, dest, alloc);
426 ASSIGN_VMD_DMA_OPS(source, dest, free);
427 ASSIGN_VMD_DMA_OPS(source, dest, mmap);
428 ASSIGN_VMD_DMA_OPS(source, dest, get_sgtable);
429 ASSIGN_VMD_DMA_OPS(source, dest, map_page);
430 ASSIGN_VMD_DMA_OPS(source, dest, unmap_page);
431 ASSIGN_VMD_DMA_OPS(source, dest, map_sg);
432 ASSIGN_VMD_DMA_OPS(source, dest, unmap_sg);
433 ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_cpu);
434 ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_device);
435 ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_cpu);
436 ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device);
437 ASSIGN_VMD_DMA_OPS(source, dest, dma_supported);
438 ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask);
439 add_dma_domain(domain);
440}
441#undef ASSIGN_VMD_DMA_OPS
442
443static char __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
444 unsigned int devfn, int reg, int len)
445{
446 char __iomem *addr = vmd->cfgbar +
447 ((bus->number - vmd->busn_start) << 20) +
448 (devfn << 12) + reg;
449
450 if ((addr - vmd->cfgbar) + len >=
451 resource_size(&vmd->dev->resource[VMD_CFGBAR]))
452 return NULL;
453
454 return addr;
455}
456
457/*
458 * CPU may deadlock if config space is not serialized on some versions of this
459 * hardware, so all config space access is done under a spinlock.
460 */
461static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
462 int len, u32 *value)
463{
464 struct vmd_dev *vmd = vmd_from_bus(bus);
465 char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
466 unsigned long flags;
467 int ret = 0;
468
469 if (!addr)
470 return -EFAULT;
471
472 spin_lock_irqsave(&vmd->cfg_lock, flags);
473 switch (len) {
474 case 1:
475 *value = readb(addr);
476 break;
477 case 2:
478 *value = readw(addr);
479 break;
480 case 4:
481 *value = readl(addr);
482 break;
483 default:
484 ret = -EINVAL;
485 break;
486 }
487 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
488 return ret;
489}
490
491/*
492 * VMD h/w converts non-posted config writes to posted memory writes. The
493 * read-back in this function forces the completion so it returns only after
494 * the config space was written, as expected.
495 */
496static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
497 int len, u32 value)
498{
499 struct vmd_dev *vmd = vmd_from_bus(bus);
500 char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
501 unsigned long flags;
502 int ret = 0;
503
504 if (!addr)
505 return -EFAULT;
506
507 spin_lock_irqsave(&vmd->cfg_lock, flags);
508 switch (len) {
509 case 1:
510 writeb(value, addr);
511 readb(addr);
512 break;
513 case 2:
514 writew(value, addr);
515 readw(addr);
516 break;
517 case 4:
518 writel(value, addr);
519 readl(addr);
520 break;
521 default:
522 ret = -EINVAL;
523 break;
524 }
525 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
526 return ret;
527}
528
529static struct pci_ops vmd_ops = {
530 .read = vmd_pci_read,
531 .write = vmd_pci_write,
532};
533
534static void vmd_attach_resources(struct vmd_dev *vmd)
535{
536 vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
537 vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
538}
539
540static void vmd_detach_resources(struct vmd_dev *vmd)
541{
542 vmd->dev->resource[VMD_MEMBAR1].child = NULL;
543 vmd->dev->resource[VMD_MEMBAR2].child = NULL;
544}
545
546/*
547 * VMD domains start at 0x10000 to not clash with ACPI _SEG domains.
548 * Per ACPI r6.0, sec 6.5.6, _SEG returns an integer, of which the lower
549 * 16 bits are the PCI Segment Group (domain) number. Other bits are
550 * currently reserved.
551 */
552static int vmd_find_free_domain(void)
553{
554 int domain = 0xffff;
555 struct pci_bus *bus = NULL;
556
557 while ((bus = pci_find_next_bus(bus)) != NULL)
558 domain = max_t(int, domain, pci_domain_nr(bus));
559 return domain + 1;
560}
561
562static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
563{
564 struct pci_sysdata *sd = &vmd->sysdata;
565 struct fwnode_handle *fn;
566 struct resource *res;
567 u32 upper_bits;
568 unsigned long flags;
569 LIST_HEAD(resources);
570 resource_size_t offset[2] = {0};
571 resource_size_t membar2_offset = 0x2000;
572 struct pci_bus *child;
573
574 /*
575 * Shadow registers may exist in certain VMD device ids which allow
576 * guests to correctly assign host physical addresses to the root ports
577 * and child devices. These registers will either return the host value
578 * or 0, depending on an enable bit in the VMD device.
579 */
580 if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
581 u32 vmlock;
582 int ret;
583
584 membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
585 ret = pci_read_config_dword(vmd->dev, PCI_REG_VMLOCK, &vmlock);
586 if (ret || vmlock == ~0)
587 return -ENODEV;
588
589 if (MB2_SHADOW_EN(vmlock)) {
590 void __iomem *membar2;
591
592 membar2 = pci_iomap(vmd->dev, VMD_MEMBAR2, 0);
593 if (!membar2)
594 return -ENOMEM;
595 offset[0] = vmd->dev->resource[VMD_MEMBAR1].start -
596 readq(membar2 + MB2_SHADOW_OFFSET);
597 offset[1] = vmd->dev->resource[VMD_MEMBAR2].start -
598 readq(membar2 + MB2_SHADOW_OFFSET + 8);
599 pci_iounmap(vmd->dev, membar2);
600 }
601 }
602
603 /*
604 * Certain VMD devices may have a root port configuration option which
605 * limits the bus range to between 0-127 or 128-255
606 */
607 if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {
608 u32 vmcap, vmconfig;
609
610 pci_read_config_dword(vmd->dev, PCI_REG_VMCAP, &vmcap);
611 pci_read_config_dword(vmd->dev, PCI_REG_VMCONFIG, &vmconfig);
612 if (BUS_RESTRICT_CAP(vmcap) &&
613 (BUS_RESTRICT_CFG(vmconfig) == 0x1))
614 vmd->busn_start = 128;
615 }
616
617 res = &vmd->dev->resource[VMD_CFGBAR];
618 vmd->resources[0] = (struct resource) {
619 .name = "VMD CFGBAR",
620 .start = vmd->busn_start,
621 .end = vmd->busn_start + (resource_size(res) >> 20) - 1,
622 .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
623 };
624
625 /*
626 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
627 * put 32-bit resources in the window.
628 *
629 * There's no hardware reason why a 64-bit window *couldn't*
630 * contain a 32-bit resource, but pbus_size_mem() computes the
631 * bridge window size assuming a 64-bit window will contain no
632 * 32-bit resources. __pci_assign_resource() enforces that
633 * artificial restriction to make sure everything will fit.
634 *
635 * The only way we could use a 64-bit non-prefetchable MEMBAR is
636 * if its address is <4GB so that we can convert it to a 32-bit
637 * resource. To be visible to the host OS, all VMD endpoints must
638 * be initially configured by platform BIOS, which includes setting
639 * up these resources. We can assume the device is configured
640 * according to the platform needs.
641 */
642 res = &vmd->dev->resource[VMD_MEMBAR1];
643 upper_bits = upper_32_bits(res->end);
644 flags = res->flags & ~IORESOURCE_SIZEALIGN;
645 if (!upper_bits)
646 flags &= ~IORESOURCE_MEM_64;
647 vmd->resources[1] = (struct resource) {
648 .name = "VMD MEMBAR1",
649 .start = res->start,
650 .end = res->end,
651 .flags = flags,
652 .parent = res,
653 };
654
655 res = &vmd->dev->resource[VMD_MEMBAR2];
656 upper_bits = upper_32_bits(res->end);
657 flags = res->flags & ~IORESOURCE_SIZEALIGN;
658 if (!upper_bits)
659 flags &= ~IORESOURCE_MEM_64;
660 vmd->resources[2] = (struct resource) {
661 .name = "VMD MEMBAR2",
662 .start = res->start + membar2_offset,
663 .end = res->end,
664 .flags = flags,
665 .parent = res,
666 };
667
668 sd->vmd_domain = true;
669 sd->domain = vmd_find_free_domain();
670 if (sd->domain < 0)
671 return sd->domain;
672
673 sd->node = pcibus_to_node(vmd->dev->bus);
674
675 fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
676 if (!fn)
677 return -ENODEV;
678
679 vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info,
680 x86_vector_domain);
681 irq_domain_free_fwnode(fn);
682 if (!vmd->irq_domain)
683 return -ENODEV;
684
685 pci_add_resource(&resources, &vmd->resources[0]);
686 pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);
687 pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]);
688
689 vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start,
690 &vmd_ops, sd, &resources);
691 if (!vmd->bus) {
692 pci_free_resource_list(&resources);
693 irq_domain_remove(vmd->irq_domain);
694 return -ENODEV;
695 }
696
697 vmd_attach_resources(vmd);
698 vmd_setup_dma_ops(vmd);
699 dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
700
701 pci_scan_child_bus(vmd->bus);
702 pci_assign_unassigned_bus_resources(vmd->bus);
703
704 /*
705 * VMD root buses are virtual and don't return true on pci_is_pcie()
706 * and will fail pcie_bus_configure_settings() early. It can instead be
707 * run on each of the real root ports.
708 */
709 list_for_each_entry(child, &vmd->bus->children, node)
710 pcie_bus_configure_settings(child);
711
712 pci_bus_add_devices(vmd->bus);
713
714 WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
715 "domain"), "Can't create symlink to domain\n");
716 return 0;
717}
718
719static irqreturn_t vmd_irq(int irq, void *data)
720{
721 struct vmd_irq_list *irqs = data;
722 struct vmd_irq *vmdirq;
723 int idx;
724
725 idx = srcu_read_lock(&irqs->srcu);
726 list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
727 generic_handle_irq(vmdirq->virq);
728 srcu_read_unlock(&irqs->srcu, idx);
729
730 return IRQ_HANDLED;
731}
732
733static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
734{
735 struct vmd_dev *vmd;
736 int i, err;
737
738 if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
739 return -ENOMEM;
740
741 vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
742 if (!vmd)
743 return -ENOMEM;
744
745 vmd->dev = dev;
746 err = pcim_enable_device(dev);
747 if (err < 0)
748 return err;
749
750 vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
751 if (!vmd->cfgbar)
752 return -ENOMEM;
753
754 pci_set_master(dev);
755 if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
756 dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
757 return -ENODEV;
758
759 vmd->msix_count = pci_msix_vec_count(dev);
760 if (vmd->msix_count < 0)
761 return -ENODEV;
762
763 vmd->msix_count = pci_alloc_irq_vectors(dev, 1, vmd->msix_count,
764 PCI_IRQ_MSIX);
765 if (vmd->msix_count < 0)
766 return vmd->msix_count;
767
768 vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
769 GFP_KERNEL);
770 if (!vmd->irqs)
771 return -ENOMEM;
772
773 for (i = 0; i < vmd->msix_count; i++) {
774 err = init_srcu_struct(&vmd->irqs[i].srcu);
775 if (err)
776 return err;
777
778 INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
779 err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
780 vmd_irq, IRQF_NO_THREAD,
781 "vmd", &vmd->irqs[i]);
782 if (err)
783 return err;
784 }
785
786 spin_lock_init(&vmd->cfg_lock);
787 pci_set_drvdata(dev, vmd);
788 err = vmd_enable_domain(vmd, (unsigned long) id->driver_data);
789 if (err)
790 return err;
791
792 dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
793 vmd->sysdata.domain);
794 return 0;
795}
796
797static void vmd_cleanup_srcu(struct vmd_dev *vmd)
798{
799 int i;
800
801 for (i = 0; i < vmd->msix_count; i++)
802 cleanup_srcu_struct(&vmd->irqs[i].srcu);
803}
804
805static void vmd_remove(struct pci_dev *dev)
806{
807 struct vmd_dev *vmd = pci_get_drvdata(dev);
808
809 sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
810 pci_stop_root_bus(vmd->bus);
811 pci_remove_root_bus(vmd->bus);
812 vmd_cleanup_srcu(vmd);
813 vmd_teardown_dma_ops(vmd);
814 vmd_detach_resources(vmd);
815 irq_domain_remove(vmd->irq_domain);
816}
817
818#ifdef CONFIG_PM_SLEEP
819static int vmd_suspend(struct device *dev)
820{
821 struct pci_dev *pdev = to_pci_dev(dev);
822 struct vmd_dev *vmd = pci_get_drvdata(pdev);
823 int i;
824
825 for (i = 0; i < vmd->msix_count; i++)
826 devm_free_irq(dev, pci_irq_vector(pdev, i), &vmd->irqs[i]);
827
828 pci_save_state(pdev);
829 return 0;
830}
831
832static int vmd_resume(struct device *dev)
833{
834 struct pci_dev *pdev = to_pci_dev(dev);
835 struct vmd_dev *vmd = pci_get_drvdata(pdev);
836 int err, i;
837
838 for (i = 0; i < vmd->msix_count; i++) {
839 err = devm_request_irq(dev, pci_irq_vector(pdev, i),
840 vmd_irq, IRQF_NO_THREAD,
841 "vmd", &vmd->irqs[i]);
842 if (err)
843 return err;
844 }
845
846 pci_restore_state(pdev);
847 return 0;
848}
849#endif
850static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
851
852static const struct pci_device_id vmd_ids[] = {
853 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_201D),},
854 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0),
855 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW |
856 VMD_FEAT_HAS_BUS_RESTRICTIONS,},
857 {0,}
858};
859MODULE_DEVICE_TABLE(pci, vmd_ids);
860
861static struct pci_driver vmd_drv = {
862 .name = "vmd",
863 .id_table = vmd_ids,
864 .probe = vmd_probe,
865 .remove = vmd_remove,
866 .driver = {
867 .pm = &vmd_dev_pm_ops,
868 },
869};
870module_pci_driver(vmd_drv);
871
872MODULE_AUTHOR("Intel Corporation");
873MODULE_LICENSE("GPL v2");
874MODULE_VERSION("0.6");
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-acpi.h>
15#include <linux/pci-ecam.h>
16#include <linux/srcu.h>
17#include <linux/rculist.h>
18#include <linux/rcupdate.h>
19
20#include <asm/irqdomain.h>
21
22#define VMD_CFGBAR 0
23#define VMD_MEMBAR1 2
24#define VMD_MEMBAR2 4
25
26#define PCI_REG_VMCAP 0x40
27#define BUS_RESTRICT_CAP(vmcap) (vmcap & 0x1)
28#define PCI_REG_VMCONFIG 0x44
29#define BUS_RESTRICT_CFG(vmcfg) ((vmcfg >> 8) & 0x3)
30#define VMCONFIG_MSI_REMAP 0x2
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
37enum 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 * Device can bypass remapping MSI-X transactions into its MSI-X table,
65 * avoiding the requirement of a VMD MSI domain for child device
66 * interrupt handling.
67 */
68 VMD_FEAT_CAN_BYPASS_MSI_REMAP = (1 << 4),
69};
70
71static DEFINE_IDA(vmd_instance_ida);
72
73/*
74 * Lock for manipulating VMD IRQ lists.
75 */
76static DEFINE_RAW_SPINLOCK(list_lock);
77
78/**
79 * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
80 * @node: list item for parent traversal.
81 * @irq: back pointer to parent.
82 * @enabled: true if driver enabled IRQ
83 * @virq: the virtual IRQ value provided to the requesting driver.
84 *
85 * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
86 * a VMD IRQ using this structure.
87 */
88struct vmd_irq {
89 struct list_head node;
90 struct vmd_irq_list *irq;
91 bool enabled;
92 unsigned int virq;
93};
94
95/**
96 * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
97 * @irq_list: the list of irq's the VMD one demuxes to.
98 * @srcu: SRCU struct for local synchronization.
99 * @count: number of child IRQs assigned to this vector; used to track
100 * sharing.
101 * @virq: The underlying VMD Linux interrupt number
102 */
103struct vmd_irq_list {
104 struct list_head irq_list;
105 struct srcu_struct srcu;
106 unsigned int count;
107 unsigned int virq;
108};
109
110struct vmd_dev {
111 struct pci_dev *dev;
112
113 spinlock_t cfg_lock;
114 void __iomem *cfgbar;
115
116 int msix_count;
117 struct vmd_irq_list *irqs;
118
119 struct pci_sysdata sysdata;
120 struct resource resources[3];
121 struct irq_domain *irq_domain;
122 struct pci_bus *bus;
123 u8 busn_start;
124 u8 first_vec;
125 char *name;
126 int instance;
127};
128
129static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
130{
131 return container_of(bus->sysdata, struct vmd_dev, sysdata);
132}
133
134static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
135 struct vmd_irq_list *irqs)
136{
137 return irqs - vmd->irqs;
138}
139
140/*
141 * Drivers managing a device in a VMD domain allocate their own IRQs as before,
142 * but the MSI entry for the hardware it's driving will be programmed with a
143 * destination ID for the VMD MSI-X table. The VMD muxes interrupts in its
144 * domain into one of its own, and the VMD driver de-muxes these for the
145 * handlers sharing that VMD IRQ. The vmd irq_domain provides the operations
146 * and irq_chip to set this up.
147 */
148static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
149{
150 struct vmd_irq *vmdirq = data->chip_data;
151 struct vmd_irq_list *irq = vmdirq->irq;
152 struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
153
154 memset(msg, 0, sizeof(*msg));
155 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
156 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
157 msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq);
158}
159
160/*
161 * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
162 */
163static void vmd_irq_enable(struct irq_data *data)
164{
165 struct vmd_irq *vmdirq = data->chip_data;
166 unsigned long flags;
167
168 raw_spin_lock_irqsave(&list_lock, flags);
169 WARN_ON(vmdirq->enabled);
170 list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
171 vmdirq->enabled = true;
172 raw_spin_unlock_irqrestore(&list_lock, flags);
173
174 data->chip->irq_unmask(data);
175}
176
177static void vmd_irq_disable(struct irq_data *data)
178{
179 struct vmd_irq *vmdirq = data->chip_data;
180 unsigned long flags;
181
182 data->chip->irq_mask(data);
183
184 raw_spin_lock_irqsave(&list_lock, flags);
185 if (vmdirq->enabled) {
186 list_del_rcu(&vmdirq->node);
187 vmdirq->enabled = false;
188 }
189 raw_spin_unlock_irqrestore(&list_lock, flags);
190}
191
192/*
193 * XXX: Stubbed until we develop acceptable way to not create conflicts with
194 * other devices sharing the same vector.
195 */
196static int vmd_irq_set_affinity(struct irq_data *data,
197 const struct cpumask *dest, bool force)
198{
199 return -EINVAL;
200}
201
202static struct irq_chip vmd_msi_controller = {
203 .name = "VMD-MSI",
204 .irq_enable = vmd_irq_enable,
205 .irq_disable = vmd_irq_disable,
206 .irq_compose_msi_msg = vmd_compose_msi_msg,
207 .irq_set_affinity = vmd_irq_set_affinity,
208};
209
210static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
211 msi_alloc_info_t *arg)
212{
213 return 0;
214}
215
216/*
217 * XXX: We can be even smarter selecting the best IRQ once we solve the
218 * affinity problem.
219 */
220static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
221{
222 unsigned long flags;
223 int i, best;
224
225 if (vmd->msix_count == 1 + vmd->first_vec)
226 return &vmd->irqs[vmd->first_vec];
227
228 /*
229 * White list for fast-interrupt handlers. All others will share the
230 * "slow" interrupt vector.
231 */
232 switch (msi_desc_to_pci_dev(desc)->class) {
233 case PCI_CLASS_STORAGE_EXPRESS:
234 break;
235 default:
236 return &vmd->irqs[vmd->first_vec];
237 }
238
239 raw_spin_lock_irqsave(&list_lock, flags);
240 best = vmd->first_vec + 1;
241 for (i = best; i < vmd->msix_count; i++)
242 if (vmd->irqs[i].count < vmd->irqs[best].count)
243 best = i;
244 vmd->irqs[best].count++;
245 raw_spin_unlock_irqrestore(&list_lock, flags);
246
247 return &vmd->irqs[best];
248}
249
250static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
251 unsigned int virq, irq_hw_number_t hwirq,
252 msi_alloc_info_t *arg)
253{
254 struct msi_desc *desc = arg->desc;
255 struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
256 struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
257
258 if (!vmdirq)
259 return -ENOMEM;
260
261 INIT_LIST_HEAD(&vmdirq->node);
262 vmdirq->irq = vmd_next_irq(vmd, desc);
263 vmdirq->virq = virq;
264
265 irq_domain_set_info(domain, virq, vmdirq->irq->virq, info->chip, vmdirq,
266 handle_untracked_irq, vmd, NULL);
267 return 0;
268}
269
270static void vmd_msi_free(struct irq_domain *domain,
271 struct msi_domain_info *info, unsigned int virq)
272{
273 struct vmd_irq *vmdirq = irq_get_chip_data(virq);
274 unsigned long flags;
275
276 synchronize_srcu(&vmdirq->irq->srcu);
277
278 /* XXX: Potential optimization to rebalance */
279 raw_spin_lock_irqsave(&list_lock, flags);
280 vmdirq->irq->count--;
281 raw_spin_unlock_irqrestore(&list_lock, flags);
282
283 kfree(vmdirq);
284}
285
286static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
287 int nvec, msi_alloc_info_t *arg)
288{
289 struct pci_dev *pdev = to_pci_dev(dev);
290 struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
291
292 if (nvec > vmd->msix_count)
293 return vmd->msix_count;
294
295 memset(arg, 0, sizeof(*arg));
296 return 0;
297}
298
299static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
300{
301 arg->desc = desc;
302}
303
304static struct msi_domain_ops vmd_msi_domain_ops = {
305 .get_hwirq = vmd_get_hwirq,
306 .msi_init = vmd_msi_init,
307 .msi_free = vmd_msi_free,
308 .msi_prepare = vmd_msi_prepare,
309 .set_desc = vmd_set_desc,
310};
311
312static struct msi_domain_info vmd_msi_domain_info = {
313 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
314 MSI_FLAG_PCI_MSIX,
315 .ops = &vmd_msi_domain_ops,
316 .chip = &vmd_msi_controller,
317};
318
319static void vmd_set_msi_remapping(struct vmd_dev *vmd, bool enable)
320{
321 u16 reg;
322
323 pci_read_config_word(vmd->dev, PCI_REG_VMCONFIG, ®);
324 reg = enable ? (reg & ~VMCONFIG_MSI_REMAP) :
325 (reg | VMCONFIG_MSI_REMAP);
326 pci_write_config_word(vmd->dev, PCI_REG_VMCONFIG, reg);
327}
328
329static int vmd_create_irq_domain(struct vmd_dev *vmd)
330{
331 struct fwnode_handle *fn;
332
333 fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
334 if (!fn)
335 return -ENODEV;
336
337 vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL);
338 if (!vmd->irq_domain) {
339 irq_domain_free_fwnode(fn);
340 return -ENODEV;
341 }
342
343 return 0;
344}
345
346static void vmd_remove_irq_domain(struct vmd_dev *vmd)
347{
348 /*
349 * Some production BIOS won't enable remapping between soft reboots.
350 * Ensure remapping is restored before unloading the driver.
351 */
352 if (!vmd->msix_count)
353 vmd_set_msi_remapping(vmd, true);
354
355 if (vmd->irq_domain) {
356 struct fwnode_handle *fn = vmd->irq_domain->fwnode;
357
358 irq_domain_remove(vmd->irq_domain);
359 irq_domain_free_fwnode(fn);
360 }
361}
362
363static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
364 unsigned int devfn, int reg, int len)
365{
366 unsigned int busnr_ecam = bus->number - vmd->busn_start;
367 u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
368
369 if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR]))
370 return NULL;
371
372 return vmd->cfgbar + offset;
373}
374
375/*
376 * CPU may deadlock if config space is not serialized on some versions of this
377 * hardware, so all config space access is done under a spinlock.
378 */
379static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
380 int len, u32 *value)
381{
382 struct vmd_dev *vmd = vmd_from_bus(bus);
383 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
384 unsigned long flags;
385 int ret = 0;
386
387 if (!addr)
388 return -EFAULT;
389
390 spin_lock_irqsave(&vmd->cfg_lock, flags);
391 switch (len) {
392 case 1:
393 *value = readb(addr);
394 break;
395 case 2:
396 *value = readw(addr);
397 break;
398 case 4:
399 *value = readl(addr);
400 break;
401 default:
402 ret = -EINVAL;
403 break;
404 }
405 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
406 return ret;
407}
408
409/*
410 * VMD h/w converts non-posted config writes to posted memory writes. The
411 * read-back in this function forces the completion so it returns only after
412 * the config space was written, as expected.
413 */
414static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
415 int len, u32 value)
416{
417 struct vmd_dev *vmd = vmd_from_bus(bus);
418 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
419 unsigned long flags;
420 int ret = 0;
421
422 if (!addr)
423 return -EFAULT;
424
425 spin_lock_irqsave(&vmd->cfg_lock, flags);
426 switch (len) {
427 case 1:
428 writeb(value, addr);
429 readb(addr);
430 break;
431 case 2:
432 writew(value, addr);
433 readw(addr);
434 break;
435 case 4:
436 writel(value, addr);
437 readl(addr);
438 break;
439 default:
440 ret = -EINVAL;
441 break;
442 }
443 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
444 return ret;
445}
446
447static struct pci_ops vmd_ops = {
448 .read = vmd_pci_read,
449 .write = vmd_pci_write,
450};
451
452#ifdef CONFIG_ACPI
453static struct acpi_device *vmd_acpi_find_companion(struct pci_dev *pci_dev)
454{
455 struct pci_host_bridge *bridge;
456 u32 busnr, addr;
457
458 if (pci_dev->bus->ops != &vmd_ops)
459 return NULL;
460
461 bridge = pci_find_host_bridge(pci_dev->bus);
462 busnr = pci_dev->bus->number - bridge->bus->number;
463 /*
464 * The address computation below is only applicable to relative bus
465 * numbers below 32.
466 */
467 if (busnr > 31)
468 return NULL;
469
470 addr = (busnr << 24) | ((u32)pci_dev->devfn << 16) | 0x8000FFFFU;
471
472 dev_dbg(&pci_dev->dev, "Looking for ACPI companion (address 0x%x)\n",
473 addr);
474
475 return acpi_find_child_device(ACPI_COMPANION(bridge->dev.parent), addr,
476 false);
477}
478
479static bool hook_installed;
480
481static void vmd_acpi_begin(void)
482{
483 if (pci_acpi_set_companion_lookup_hook(vmd_acpi_find_companion))
484 return;
485
486 hook_installed = true;
487}
488
489static void vmd_acpi_end(void)
490{
491 if (!hook_installed)
492 return;
493
494 pci_acpi_clear_companion_lookup_hook();
495 hook_installed = false;
496}
497#else
498static inline void vmd_acpi_begin(void) { }
499static inline void vmd_acpi_end(void) { }
500#endif /* CONFIG_ACPI */
501
502static void vmd_domain_reset(struct vmd_dev *vmd)
503{
504 u16 bus, max_buses = resource_size(&vmd->resources[0]);
505 u8 dev, functions, fn, hdr_type;
506 char __iomem *base;
507
508 for (bus = 0; bus < max_buses; bus++) {
509 for (dev = 0; dev < 32; dev++) {
510 base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus,
511 PCI_DEVFN(dev, 0), 0);
512
513 hdr_type = readb(base + PCI_HEADER_TYPE) &
514 PCI_HEADER_TYPE_MASK;
515
516 functions = (hdr_type & 0x80) ? 8 : 1;
517 for (fn = 0; fn < functions; fn++) {
518 base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus,
519 PCI_DEVFN(dev, fn), 0);
520
521 hdr_type = readb(base + PCI_HEADER_TYPE) &
522 PCI_HEADER_TYPE_MASK;
523
524 if (hdr_type != PCI_HEADER_TYPE_BRIDGE ||
525 (readw(base + PCI_CLASS_DEVICE) !=
526 PCI_CLASS_BRIDGE_PCI))
527 continue;
528
529 memset_io(base + PCI_IO_BASE, 0,
530 PCI_ROM_ADDRESS1 - PCI_IO_BASE);
531 }
532 }
533 }
534}
535
536static void vmd_attach_resources(struct vmd_dev *vmd)
537{
538 vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
539 vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
540}
541
542static void vmd_detach_resources(struct vmd_dev *vmd)
543{
544 vmd->dev->resource[VMD_MEMBAR1].child = NULL;
545 vmd->dev->resource[VMD_MEMBAR2].child = NULL;
546}
547
548/*
549 * VMD domains start at 0x10000 to not clash with ACPI _SEG domains.
550 * Per ACPI r6.0, sec 6.5.6, _SEG returns an integer, of which the lower
551 * 16 bits are the PCI Segment Group (domain) number. Other bits are
552 * currently reserved.
553 */
554static int vmd_find_free_domain(void)
555{
556 int domain = 0xffff;
557 struct pci_bus *bus = NULL;
558
559 while ((bus = pci_find_next_bus(bus)) != NULL)
560 domain = max_t(int, domain, pci_domain_nr(bus));
561 return domain + 1;
562}
563
564static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
565 resource_size_t *offset1,
566 resource_size_t *offset2)
567{
568 struct pci_dev *dev = vmd->dev;
569 u64 phys1, phys2;
570
571 if (native_hint) {
572 u32 vmlock;
573 int ret;
574
575 ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
576 if (ret || PCI_POSSIBLE_ERROR(vmlock))
577 return -ENODEV;
578
579 if (MB2_SHADOW_EN(vmlock)) {
580 void __iomem *membar2;
581
582 membar2 = pci_iomap(dev, VMD_MEMBAR2, 0);
583 if (!membar2)
584 return -ENOMEM;
585 phys1 = readq(membar2 + MB2_SHADOW_OFFSET);
586 phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8);
587 pci_iounmap(dev, membar2);
588 } else
589 return 0;
590 } else {
591 /* Hypervisor-Emulated Vendor-Specific Capability */
592 int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
593 u32 reg, regu;
594
595 pci_read_config_dword(dev, pos + 4, ®);
596
597 /* "SHDW" */
598 if (pos && reg == 0x53484457) {
599 pci_read_config_dword(dev, pos + 8, ®);
600 pci_read_config_dword(dev, pos + 12, ®u);
601 phys1 = (u64) regu << 32 | reg;
602
603 pci_read_config_dword(dev, pos + 16, ®);
604 pci_read_config_dword(dev, pos + 20, ®u);
605 phys2 = (u64) regu << 32 | reg;
606 } else
607 return 0;
608 }
609
610 *offset1 = dev->resource[VMD_MEMBAR1].start -
611 (phys1 & PCI_BASE_ADDRESS_MEM_MASK);
612 *offset2 = dev->resource[VMD_MEMBAR2].start -
613 (phys2 & PCI_BASE_ADDRESS_MEM_MASK);
614
615 return 0;
616}
617
618static int vmd_get_bus_number_start(struct vmd_dev *vmd)
619{
620 struct pci_dev *dev = vmd->dev;
621 u16 reg;
622
623 pci_read_config_word(dev, PCI_REG_VMCAP, ®);
624 if (BUS_RESTRICT_CAP(reg)) {
625 pci_read_config_word(dev, PCI_REG_VMCONFIG, ®);
626
627 switch (BUS_RESTRICT_CFG(reg)) {
628 case 0:
629 vmd->busn_start = 0;
630 break;
631 case 1:
632 vmd->busn_start = 128;
633 break;
634 case 2:
635 vmd->busn_start = 224;
636 break;
637 default:
638 pci_err(dev, "Unknown Bus Offset Setting (%d)\n",
639 BUS_RESTRICT_CFG(reg));
640 return -ENODEV;
641 }
642 }
643
644 return 0;
645}
646
647static irqreturn_t vmd_irq(int irq, void *data)
648{
649 struct vmd_irq_list *irqs = data;
650 struct vmd_irq *vmdirq;
651 int idx;
652
653 idx = srcu_read_lock(&irqs->srcu);
654 list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
655 generic_handle_irq(vmdirq->virq);
656 srcu_read_unlock(&irqs->srcu, idx);
657
658 return IRQ_HANDLED;
659}
660
661static int vmd_alloc_irqs(struct vmd_dev *vmd)
662{
663 struct pci_dev *dev = vmd->dev;
664 int i, err;
665
666 vmd->msix_count = pci_msix_vec_count(dev);
667 if (vmd->msix_count < 0)
668 return -ENODEV;
669
670 vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1,
671 vmd->msix_count, PCI_IRQ_MSIX);
672 if (vmd->msix_count < 0)
673 return vmd->msix_count;
674
675 vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
676 GFP_KERNEL);
677 if (!vmd->irqs)
678 return -ENOMEM;
679
680 for (i = 0; i < vmd->msix_count; i++) {
681 err = init_srcu_struct(&vmd->irqs[i].srcu);
682 if (err)
683 return err;
684
685 INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
686 vmd->irqs[i].virq = pci_irq_vector(dev, i);
687 err = devm_request_irq(&dev->dev, vmd->irqs[i].virq,
688 vmd_irq, IRQF_NO_THREAD,
689 vmd->name, &vmd->irqs[i]);
690 if (err)
691 return err;
692 }
693
694 return 0;
695}
696
697/*
698 * Since VMD is an aperture to regular PCIe root ports, only allow it to
699 * control features that the OS is allowed to control on the physical PCI bus.
700 */
701static void vmd_copy_host_bridge_flags(struct pci_host_bridge *root_bridge,
702 struct pci_host_bridge *vmd_bridge)
703{
704 vmd_bridge->native_pcie_hotplug = root_bridge->native_pcie_hotplug;
705 vmd_bridge->native_shpc_hotplug = root_bridge->native_shpc_hotplug;
706 vmd_bridge->native_aer = root_bridge->native_aer;
707 vmd_bridge->native_pme = root_bridge->native_pme;
708 vmd_bridge->native_ltr = root_bridge->native_ltr;
709 vmd_bridge->native_dpc = root_bridge->native_dpc;
710}
711
712static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
713{
714 struct pci_sysdata *sd = &vmd->sysdata;
715 struct resource *res;
716 u32 upper_bits;
717 unsigned long flags;
718 LIST_HEAD(resources);
719 resource_size_t offset[2] = {0};
720 resource_size_t membar2_offset = 0x2000;
721 struct pci_bus *child;
722 struct pci_dev *dev;
723 int ret;
724
725 /*
726 * Shadow registers may exist in certain VMD device ids which allow
727 * guests to correctly assign host physical addresses to the root ports
728 * and child devices. These registers will either return the host value
729 * or 0, depending on an enable bit in the VMD device.
730 */
731 if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
732 membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
733 ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]);
734 if (ret)
735 return ret;
736 } else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
737 ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]);
738 if (ret)
739 return ret;
740 }
741
742 /*
743 * Certain VMD devices may have a root port configuration option which
744 * limits the bus range to between 0-127, 128-255, or 224-255
745 */
746 if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {
747 ret = vmd_get_bus_number_start(vmd);
748 if (ret)
749 return ret;
750 }
751
752 res = &vmd->dev->resource[VMD_CFGBAR];
753 vmd->resources[0] = (struct resource) {
754 .name = "VMD CFGBAR",
755 .start = vmd->busn_start,
756 .end = vmd->busn_start + (resource_size(res) >> 20) - 1,
757 .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
758 };
759
760 /*
761 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
762 * put 32-bit resources in the window.
763 *
764 * There's no hardware reason why a 64-bit window *couldn't*
765 * contain a 32-bit resource, but pbus_size_mem() computes the
766 * bridge window size assuming a 64-bit window will contain no
767 * 32-bit resources. __pci_assign_resource() enforces that
768 * artificial restriction to make sure everything will fit.
769 *
770 * The only way we could use a 64-bit non-prefetchable MEMBAR is
771 * if its address is <4GB so that we can convert it to a 32-bit
772 * resource. To be visible to the host OS, all VMD endpoints must
773 * be initially configured by platform BIOS, which includes setting
774 * up these resources. We can assume the device is configured
775 * according to the platform needs.
776 */
777 res = &vmd->dev->resource[VMD_MEMBAR1];
778 upper_bits = upper_32_bits(res->end);
779 flags = res->flags & ~IORESOURCE_SIZEALIGN;
780 if (!upper_bits)
781 flags &= ~IORESOURCE_MEM_64;
782 vmd->resources[1] = (struct resource) {
783 .name = "VMD MEMBAR1",
784 .start = res->start,
785 .end = res->end,
786 .flags = flags,
787 .parent = res,
788 };
789
790 res = &vmd->dev->resource[VMD_MEMBAR2];
791 upper_bits = upper_32_bits(res->end);
792 flags = res->flags & ~IORESOURCE_SIZEALIGN;
793 if (!upper_bits)
794 flags &= ~IORESOURCE_MEM_64;
795 vmd->resources[2] = (struct resource) {
796 .name = "VMD MEMBAR2",
797 .start = res->start + membar2_offset,
798 .end = res->end,
799 .flags = flags,
800 .parent = res,
801 };
802
803 sd->vmd_dev = vmd->dev;
804 sd->domain = vmd_find_free_domain();
805 if (sd->domain < 0)
806 return sd->domain;
807
808 sd->node = pcibus_to_node(vmd->dev->bus);
809
810 /*
811 * Currently MSI remapping must be enabled in guest passthrough mode
812 * due to some missing interrupt remapping plumbing. This is probably
813 * acceptable because the guest is usually CPU-limited and MSI
814 * remapping doesn't become a performance bottleneck.
815 */
816 if (!(features & VMD_FEAT_CAN_BYPASS_MSI_REMAP) ||
817 offset[0] || offset[1]) {
818 ret = vmd_alloc_irqs(vmd);
819 if (ret)
820 return ret;
821
822 vmd_set_msi_remapping(vmd, true);
823
824 ret = vmd_create_irq_domain(vmd);
825 if (ret)
826 return ret;
827
828 /*
829 * Override the IRQ domain bus token so the domain can be
830 * distinguished from a regular PCI/MSI domain.
831 */
832 irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI);
833 } else {
834 vmd_set_msi_remapping(vmd, false);
835 }
836
837 pci_add_resource(&resources, &vmd->resources[0]);
838 pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);
839 pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]);
840
841 vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start,
842 &vmd_ops, sd, &resources);
843 if (!vmd->bus) {
844 pci_free_resource_list(&resources);
845 vmd_remove_irq_domain(vmd);
846 return -ENODEV;
847 }
848
849 vmd_copy_host_bridge_flags(pci_find_host_bridge(vmd->dev->bus),
850 to_pci_host_bridge(vmd->bus->bridge));
851
852 vmd_attach_resources(vmd);
853 if (vmd->irq_domain)
854 dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
855 else
856 dev_set_msi_domain(&vmd->bus->dev,
857 dev_get_msi_domain(&vmd->dev->dev));
858
859 vmd_acpi_begin();
860
861 pci_scan_child_bus(vmd->bus);
862 vmd_domain_reset(vmd);
863
864 /* When Intel VMD is enabled, the OS does not discover the Root Ports
865 * owned by Intel VMD within the MMCFG space. pci_reset_bus() applies
866 * a reset to the parent of the PCI device supplied as argument. This
867 * is why we pass a child device, so the reset can be triggered at
868 * the Intel bridge level and propagated to all the children in the
869 * hierarchy.
870 */
871 list_for_each_entry(child, &vmd->bus->children, node) {
872 if (!list_empty(&child->devices)) {
873 dev = list_first_entry(&child->devices,
874 struct pci_dev, bus_list);
875 if (pci_reset_bus(dev))
876 pci_warn(dev, "can't reset device: %d\n", ret);
877
878 break;
879 }
880 }
881
882 pci_assign_unassigned_bus_resources(vmd->bus);
883
884 /*
885 * VMD root buses are virtual and don't return true on pci_is_pcie()
886 * and will fail pcie_bus_configure_settings() early. It can instead be
887 * run on each of the real root ports.
888 */
889 list_for_each_entry(child, &vmd->bus->children, node)
890 pcie_bus_configure_settings(child);
891
892 pci_bus_add_devices(vmd->bus);
893
894 vmd_acpi_end();
895
896 WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
897 "domain"), "Can't create symlink to domain\n");
898 return 0;
899}
900
901static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
902{
903 unsigned long features = (unsigned long) id->driver_data;
904 struct vmd_dev *vmd;
905 int err;
906
907 if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
908 return -ENOMEM;
909
910 vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
911 if (!vmd)
912 return -ENOMEM;
913
914 vmd->dev = dev;
915 vmd->instance = ida_simple_get(&vmd_instance_ida, 0, 0, GFP_KERNEL);
916 if (vmd->instance < 0)
917 return vmd->instance;
918
919 vmd->name = devm_kasprintf(&dev->dev, GFP_KERNEL, "vmd%d",
920 vmd->instance);
921 if (!vmd->name) {
922 err = -ENOMEM;
923 goto out_release_instance;
924 }
925
926 err = pcim_enable_device(dev);
927 if (err < 0)
928 goto out_release_instance;
929
930 vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
931 if (!vmd->cfgbar) {
932 err = -ENOMEM;
933 goto out_release_instance;
934 }
935
936 pci_set_master(dev);
937 if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
938 dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32))) {
939 err = -ENODEV;
940 goto out_release_instance;
941 }
942
943 if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
944 vmd->first_vec = 1;
945
946 spin_lock_init(&vmd->cfg_lock);
947 pci_set_drvdata(dev, vmd);
948 err = vmd_enable_domain(vmd, features);
949 if (err)
950 goto out_release_instance;
951
952 dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
953 vmd->sysdata.domain);
954 return 0;
955
956 out_release_instance:
957 ida_simple_remove(&vmd_instance_ida, vmd->instance);
958 return err;
959}
960
961static void vmd_cleanup_srcu(struct vmd_dev *vmd)
962{
963 int i;
964
965 for (i = 0; i < vmd->msix_count; i++)
966 cleanup_srcu_struct(&vmd->irqs[i].srcu);
967}
968
969static void vmd_remove(struct pci_dev *dev)
970{
971 struct vmd_dev *vmd = pci_get_drvdata(dev);
972
973 sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
974 pci_stop_root_bus(vmd->bus);
975 pci_remove_root_bus(vmd->bus);
976 vmd_cleanup_srcu(vmd);
977 vmd_detach_resources(vmd);
978 vmd_remove_irq_domain(vmd);
979 ida_simple_remove(&vmd_instance_ida, vmd->instance);
980}
981
982#ifdef CONFIG_PM_SLEEP
983static int vmd_suspend(struct device *dev)
984{
985 struct pci_dev *pdev = to_pci_dev(dev);
986 struct vmd_dev *vmd = pci_get_drvdata(pdev);
987 int i;
988
989 for (i = 0; i < vmd->msix_count; i++)
990 devm_free_irq(dev, vmd->irqs[i].virq, &vmd->irqs[i]);
991
992 return 0;
993}
994
995static int vmd_resume(struct device *dev)
996{
997 struct pci_dev *pdev = to_pci_dev(dev);
998 struct vmd_dev *vmd = pci_get_drvdata(pdev);
999 int err, i;
1000
1001 if (vmd->irq_domain)
1002 vmd_set_msi_remapping(vmd, true);
1003 else
1004 vmd_set_msi_remapping(vmd, false);
1005
1006 for (i = 0; i < vmd->msix_count; i++) {
1007 err = devm_request_irq(dev, vmd->irqs[i].virq,
1008 vmd_irq, IRQF_NO_THREAD,
1009 vmd->name, &vmd->irqs[i]);
1010 if (err)
1011 return err;
1012 }
1013
1014 return 0;
1015}
1016#endif
1017static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
1018
1019static const struct pci_device_id vmd_ids[] = {
1020 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_201D),
1021 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP,},
1022 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0),
1023 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW |
1024 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1025 VMD_FEAT_CAN_BYPASS_MSI_REMAP,},
1026 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x467f),
1027 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1028 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1029 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1030 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x4c3d),
1031 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1032 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1033 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1034 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xa77f),
1035 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1036 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1037 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1038 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x7d0b),
1039 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1040 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1041 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1042 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xad0b),
1043 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1044 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1045 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1046 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
1047 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
1048 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1049 VMD_FEAT_OFFSET_FIRST_VECTOR,},
1050 {0,}
1051};
1052MODULE_DEVICE_TABLE(pci, vmd_ids);
1053
1054static struct pci_driver vmd_drv = {
1055 .name = "vmd",
1056 .id_table = vmd_ids,
1057 .probe = vmd_probe,
1058 .remove = vmd_remove,
1059 .driver = {
1060 .pm = &vmd_dev_pm_ops,
1061 },
1062};
1063module_pci_driver(vmd_drv);
1064
1065MODULE_AUTHOR("Intel Corporation");
1066MODULE_LICENSE("GPL v2");
1067MODULE_VERSION("0.6");