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 #include <asm/device.h>
22 #include <asm/msi.h>
23
24 #define VMD_CFGBAR 0
25 #define VMD_MEMBAR1 2
26 #define VMD_MEMBAR2 4
27
28 #define PCI_REG_VMCAP 0x40
29 #define BUS_RESTRICT_CAP(vmcap) (vmcap & 0x1)
30 #define PCI_REG_VMCONFIG 0x44
31 #define BUS_RESTRICT_CFG(vmcfg) ((vmcfg >> 8) & 0x3)
32 #define VMCONFIG_MSI_REMAP 0x2
33 #define PCI_REG_VMLOCK 0x70
34 #define MB2_SHADOW_EN(vmlock) (vmlock & 0x2)
35
36 #define MB2_SHADOW_OFFSET 0x2000
37 #define MB2_SHADOW_SIZE 16
38
39 enum vmd_features {
40 /*
41 * Device may contain registers which hint the physical location of the
42 * membars, in order to allow proper address translation during
43 * resource assignment to enable guest virtualization
44 */
45 VMD_FEAT_HAS_MEMBAR_SHADOW = (1 << 0),
46
47 /*
48 * Device may provide root port configuration information which limits
49 * bus numbering
50 */
51 VMD_FEAT_HAS_BUS_RESTRICTIONS = (1 << 1),
52
53 /*
54 * Device contains physical location shadow registers in
55 * vendor-specific capability space
56 */
57 VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP = (1 << 2),
58
59 /*
60 * Device may use MSI-X vector 0 for software triggering and will not
61 * be used for MSI remapping
62 */
63 VMD_FEAT_OFFSET_FIRST_VECTOR = (1 << 3),
64
65 /*
66 * Device can bypass remapping MSI-X transactions into its MSI-X table,
67 * avoiding the requirement of a VMD MSI domain for child device
68 * interrupt handling.
69 */
70 VMD_FEAT_CAN_BYPASS_MSI_REMAP = (1 << 4),
71 };
72
73 /*
74 * Lock for manipulating VMD IRQ lists.
75 */
76 static 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 */
88 struct 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 */
102 struct vmd_irq_list {
103 struct list_head irq_list;
104 struct srcu_struct srcu;
105 unsigned int count;
106 };
107
108 struct vmd_dev {
109 struct pci_dev *dev;
110
111 spinlock_t cfg_lock;
112 void __iomem *cfgbar;
113
114 int msix_count;
115 struct vmd_irq_list *irqs;
116
117 struct pci_sysdata sysdata;
118 struct resource resources[3];
119 struct irq_domain *irq_domain;
120 struct pci_bus *bus;
121 u8 busn_start;
122 u8 first_vec;
123 };
124
vmd_from_bus(struct pci_bus * bus)125 static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
126 {
127 return container_of(bus->sysdata, struct vmd_dev, sysdata);
128 }
129
index_from_irqs(struct vmd_dev * vmd,struct vmd_irq_list * irqs)130 static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
131 struct vmd_irq_list *irqs)
132 {
133 return irqs - vmd->irqs;
134 }
135
136 /*
137 * Drivers managing a device in a VMD domain allocate their own IRQs as before,
138 * but the MSI entry for the hardware it's driving will be programmed with a
139 * destination ID for the VMD MSI-X table. The VMD muxes interrupts in its
140 * domain into one of its own, and the VMD driver de-muxes these for the
141 * handlers sharing that VMD IRQ. The vmd irq_domain provides the operations
142 * and irq_chip to set this up.
143 */
vmd_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)144 static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
145 {
146 struct vmd_irq *vmdirq = data->chip_data;
147 struct vmd_irq_list *irq = vmdirq->irq;
148 struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
149
150 memset(msg, 0, sizeof(*msg));
151 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
152 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
153 msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq);
154 }
155
156 /*
157 * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
158 */
vmd_irq_enable(struct irq_data * data)159 static void vmd_irq_enable(struct irq_data *data)
160 {
161 struct vmd_irq *vmdirq = data->chip_data;
162 unsigned long flags;
163
164 raw_spin_lock_irqsave(&list_lock, flags);
165 WARN_ON(vmdirq->enabled);
166 list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
167 vmdirq->enabled = true;
168 raw_spin_unlock_irqrestore(&list_lock, flags);
169
170 data->chip->irq_unmask(data);
171 }
172
vmd_irq_disable(struct irq_data * data)173 static void vmd_irq_disable(struct irq_data *data)
174 {
175 struct vmd_irq *vmdirq = data->chip_data;
176 unsigned long flags;
177
178 data->chip->irq_mask(data);
179
180 raw_spin_lock_irqsave(&list_lock, flags);
181 if (vmdirq->enabled) {
182 list_del_rcu(&vmdirq->node);
183 vmdirq->enabled = false;
184 }
185 raw_spin_unlock_irqrestore(&list_lock, flags);
186 }
187
188 /*
189 * XXX: Stubbed until we develop acceptable way to not create conflicts with
190 * other devices sharing the same vector.
191 */
vmd_irq_set_affinity(struct irq_data * data,const struct cpumask * dest,bool force)192 static int vmd_irq_set_affinity(struct irq_data *data,
193 const struct cpumask *dest, bool force)
194 {
195 return -EINVAL;
196 }
197
198 static struct irq_chip vmd_msi_controller = {
199 .name = "VMD-MSI",
200 .irq_enable = vmd_irq_enable,
201 .irq_disable = vmd_irq_disable,
202 .irq_compose_msi_msg = vmd_compose_msi_msg,
203 .irq_set_affinity = vmd_irq_set_affinity,
204 };
205
vmd_get_hwirq(struct msi_domain_info * info,msi_alloc_info_t * arg)206 static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
207 msi_alloc_info_t *arg)
208 {
209 return 0;
210 }
211
212 /*
213 * XXX: We can be even smarter selecting the best IRQ once we solve the
214 * affinity problem.
215 */
vmd_next_irq(struct vmd_dev * vmd,struct msi_desc * desc)216 static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
217 {
218 unsigned long flags;
219 int i, best;
220
221 if (vmd->msix_count == 1 + vmd->first_vec)
222 return &vmd->irqs[vmd->first_vec];
223
224 /*
225 * White list for fast-interrupt handlers. All others will share the
226 * "slow" interrupt vector.
227 */
228 switch (msi_desc_to_pci_dev(desc)->class) {
229 case PCI_CLASS_STORAGE_EXPRESS:
230 break;
231 default:
232 return &vmd->irqs[vmd->first_vec];
233 }
234
235 raw_spin_lock_irqsave(&list_lock, flags);
236 best = vmd->first_vec + 1;
237 for (i = best; i < vmd->msix_count; i++)
238 if (vmd->irqs[i].count < vmd->irqs[best].count)
239 best = i;
240 vmd->irqs[best].count++;
241 raw_spin_unlock_irqrestore(&list_lock, flags);
242
243 return &vmd->irqs[best];
244 }
245
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)246 static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
247 unsigned int virq, irq_hw_number_t hwirq,
248 msi_alloc_info_t *arg)
249 {
250 struct msi_desc *desc = arg->desc;
251 struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
252 struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
253 unsigned int index, vector;
254
255 if (!vmdirq)
256 return -ENOMEM;
257
258 INIT_LIST_HEAD(&vmdirq->node);
259 vmdirq->irq = vmd_next_irq(vmd, desc);
260 vmdirq->virq = virq;
261 index = index_from_irqs(vmd, vmdirq->irq);
262 vector = pci_irq_vector(vmd->dev, index);
263
264 irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
265 handle_untracked_irq, vmd, NULL);
266 return 0;
267 }
268
vmd_msi_free(struct irq_domain * domain,struct msi_domain_info * info,unsigned int virq)269 static void vmd_msi_free(struct irq_domain *domain,
270 struct msi_domain_info *info, unsigned int virq)
271 {
272 struct vmd_irq *vmdirq = irq_get_chip_data(virq);
273 unsigned long flags;
274
275 synchronize_srcu(&vmdirq->irq->srcu);
276
277 /* XXX: Potential optimization to rebalance */
278 raw_spin_lock_irqsave(&list_lock, flags);
279 vmdirq->irq->count--;
280 raw_spin_unlock_irqrestore(&list_lock, flags);
281
282 kfree(vmdirq);
283 }
284
vmd_msi_prepare(struct irq_domain * domain,struct device * dev,int nvec,msi_alloc_info_t * arg)285 static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
286 int nvec, msi_alloc_info_t *arg)
287 {
288 struct pci_dev *pdev = to_pci_dev(dev);
289 struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
290
291 if (nvec > vmd->msix_count)
292 return vmd->msix_count;
293
294 memset(arg, 0, sizeof(*arg));
295 return 0;
296 }
297
vmd_set_desc(msi_alloc_info_t * arg,struct msi_desc * desc)298 static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
299 {
300 arg->desc = desc;
301 }
302
303 static struct msi_domain_ops vmd_msi_domain_ops = {
304 .get_hwirq = vmd_get_hwirq,
305 .msi_init = vmd_msi_init,
306 .msi_free = vmd_msi_free,
307 .msi_prepare = vmd_msi_prepare,
308 .set_desc = vmd_set_desc,
309 };
310
311 static struct msi_domain_info vmd_msi_domain_info = {
312 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
313 MSI_FLAG_PCI_MSIX,
314 .ops = &vmd_msi_domain_ops,
315 .chip = &vmd_msi_controller,
316 };
317
vmd_set_msi_remapping(struct vmd_dev * vmd,bool enable)318 static void vmd_set_msi_remapping(struct vmd_dev *vmd, bool enable)
319 {
320 u16 reg;
321
322 pci_read_config_word(vmd->dev, PCI_REG_VMCONFIG, ®);
323 reg = enable ? (reg & ~VMCONFIG_MSI_REMAP) :
324 (reg | VMCONFIG_MSI_REMAP);
325 pci_write_config_word(vmd->dev, PCI_REG_VMCONFIG, reg);
326 }
327
vmd_create_irq_domain(struct vmd_dev * vmd)328 static int vmd_create_irq_domain(struct vmd_dev *vmd)
329 {
330 struct fwnode_handle *fn;
331
332 fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
333 if (!fn)
334 return -ENODEV;
335
336 vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL);
337 if (!vmd->irq_domain) {
338 irq_domain_free_fwnode(fn);
339 return -ENODEV;
340 }
341
342 return 0;
343 }
344
vmd_remove_irq_domain(struct vmd_dev * vmd)345 static void vmd_remove_irq_domain(struct vmd_dev *vmd)
346 {
347 /*
348 * Some production BIOS won't enable remapping between soft reboots.
349 * Ensure remapping is restored before unloading the driver.
350 */
351 if (!vmd->msix_count)
352 vmd_set_msi_remapping(vmd, true);
353
354 if (vmd->irq_domain) {
355 struct fwnode_handle *fn = vmd->irq_domain->fwnode;
356
357 irq_domain_remove(vmd->irq_domain);
358 irq_domain_free_fwnode(fn);
359 }
360 }
361
vmd_cfg_addr(struct vmd_dev * vmd,struct pci_bus * bus,unsigned int devfn,int reg,int len)362 static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
363 unsigned int devfn, int reg, int len)
364 {
365 unsigned int busnr_ecam = bus->number - vmd->busn_start;
366 u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
367
368 if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR]))
369 return NULL;
370
371 return vmd->cfgbar + offset;
372 }
373
374 /*
375 * CPU may deadlock if config space is not serialized on some versions of this
376 * hardware, so all config space access is done under a spinlock.
377 */
vmd_pci_read(struct pci_bus * bus,unsigned int devfn,int reg,int len,u32 * value)378 static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
379 int len, u32 *value)
380 {
381 struct vmd_dev *vmd = vmd_from_bus(bus);
382 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
383 unsigned long flags;
384 int ret = 0;
385
386 if (!addr)
387 return -EFAULT;
388
389 spin_lock_irqsave(&vmd->cfg_lock, flags);
390 switch (len) {
391 case 1:
392 *value = readb(addr);
393 break;
394 case 2:
395 *value = readw(addr);
396 break;
397 case 4:
398 *value = readl(addr);
399 break;
400 default:
401 ret = -EINVAL;
402 break;
403 }
404 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
405 return ret;
406 }
407
408 /*
409 * VMD h/w converts non-posted config writes to posted memory writes. The
410 * read-back in this function forces the completion so it returns only after
411 * the config space was written, as expected.
412 */
vmd_pci_write(struct pci_bus * bus,unsigned int devfn,int reg,int len,u32 value)413 static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
414 int len, u32 value)
415 {
416 struct vmd_dev *vmd = vmd_from_bus(bus);
417 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
418 unsigned long flags;
419 int ret = 0;
420
421 if (!addr)
422 return -EFAULT;
423
424 spin_lock_irqsave(&vmd->cfg_lock, flags);
425 switch (len) {
426 case 1:
427 writeb(value, addr);
428 readb(addr);
429 break;
430 case 2:
431 writew(value, addr);
432 readw(addr);
433 break;
434 case 4:
435 writel(value, addr);
436 readl(addr);
437 break;
438 default:
439 ret = -EINVAL;
440 break;
441 }
442 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
443 return ret;
444 }
445
446 static struct pci_ops vmd_ops = {
447 .read = vmd_pci_read,
448 .write = vmd_pci_write,
449 };
450
451 #ifdef CONFIG_ACPI
vmd_acpi_find_companion(struct pci_dev * pci_dev)452 static struct acpi_device *vmd_acpi_find_companion(struct pci_dev *pci_dev)
453 {
454 struct pci_host_bridge *bridge;
455 u32 busnr, addr;
456
457 if (pci_dev->bus->ops != &vmd_ops)
458 return NULL;
459
460 bridge = pci_find_host_bridge(pci_dev->bus);
461 busnr = pci_dev->bus->number - bridge->bus->number;
462 /*
463 * The address computation below is only applicable to relative bus
464 * numbers below 32.
465 */
466 if (busnr > 31)
467 return NULL;
468
469 addr = (busnr << 24) | ((u32)pci_dev->devfn << 16) | 0x8000FFFFU;
470
471 dev_dbg(&pci_dev->dev, "Looking for ACPI companion (address 0x%x)\n",
472 addr);
473
474 return acpi_find_child_device(ACPI_COMPANION(bridge->dev.parent), addr,
475 false);
476 }
477
478 static bool hook_installed;
479
vmd_acpi_begin(void)480 static void vmd_acpi_begin(void)
481 {
482 if (pci_acpi_set_companion_lookup_hook(vmd_acpi_find_companion))
483 return;
484
485 hook_installed = true;
486 }
487
vmd_acpi_end(void)488 static void vmd_acpi_end(void)
489 {
490 if (!hook_installed)
491 return;
492
493 pci_acpi_clear_companion_lookup_hook();
494 hook_installed = false;
495 }
496 #else
vmd_acpi_begin(void)497 static inline void vmd_acpi_begin(void) { }
vmd_acpi_end(void)498 static inline void vmd_acpi_end(void) { }
499 #endif /* CONFIG_ACPI */
500
vmd_attach_resources(struct vmd_dev * vmd)501 static void vmd_attach_resources(struct vmd_dev *vmd)
502 {
503 vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
504 vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
505 }
506
vmd_detach_resources(struct vmd_dev * vmd)507 static void vmd_detach_resources(struct vmd_dev *vmd)
508 {
509 vmd->dev->resource[VMD_MEMBAR1].child = NULL;
510 vmd->dev->resource[VMD_MEMBAR2].child = NULL;
511 }
512
513 /*
514 * VMD domains start at 0x10000 to not clash with ACPI _SEG domains.
515 * Per ACPI r6.0, sec 6.5.6, _SEG returns an integer, of which the lower
516 * 16 bits are the PCI Segment Group (domain) number. Other bits are
517 * currently reserved.
518 */
vmd_find_free_domain(void)519 static int vmd_find_free_domain(void)
520 {
521 int domain = 0xffff;
522 struct pci_bus *bus = NULL;
523
524 while ((bus = pci_find_next_bus(bus)) != NULL)
525 domain = max_t(int, domain, pci_domain_nr(bus));
526 return domain + 1;
527 }
528
vmd_get_phys_offsets(struct vmd_dev * vmd,bool native_hint,resource_size_t * offset1,resource_size_t * offset2)529 static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
530 resource_size_t *offset1,
531 resource_size_t *offset2)
532 {
533 struct pci_dev *dev = vmd->dev;
534 u64 phys1, phys2;
535
536 if (native_hint) {
537 u32 vmlock;
538 int ret;
539
540 ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
541 if (ret || vmlock == ~0)
542 return -ENODEV;
543
544 if (MB2_SHADOW_EN(vmlock)) {
545 void __iomem *membar2;
546
547 membar2 = pci_iomap(dev, VMD_MEMBAR2, 0);
548 if (!membar2)
549 return -ENOMEM;
550 phys1 = readq(membar2 + MB2_SHADOW_OFFSET);
551 phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8);
552 pci_iounmap(dev, membar2);
553 } else
554 return 0;
555 } else {
556 /* Hypervisor-Emulated Vendor-Specific Capability */
557 int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
558 u32 reg, regu;
559
560 pci_read_config_dword(dev, pos + 4, ®);
561
562 /* "SHDW" */
563 if (pos && reg == 0x53484457) {
564 pci_read_config_dword(dev, pos + 8, ®);
565 pci_read_config_dword(dev, pos + 12, ®u);
566 phys1 = (u64) regu << 32 | reg;
567
568 pci_read_config_dword(dev, pos + 16, ®);
569 pci_read_config_dword(dev, pos + 20, ®u);
570 phys2 = (u64) regu << 32 | reg;
571 } else
572 return 0;
573 }
574
575 *offset1 = dev->resource[VMD_MEMBAR1].start -
576 (phys1 & PCI_BASE_ADDRESS_MEM_MASK);
577 *offset2 = dev->resource[VMD_MEMBAR2].start -
578 (phys2 & PCI_BASE_ADDRESS_MEM_MASK);
579
580 return 0;
581 }
582
vmd_get_bus_number_start(struct vmd_dev * vmd)583 static int vmd_get_bus_number_start(struct vmd_dev *vmd)
584 {
585 struct pci_dev *dev = vmd->dev;
586 u16 reg;
587
588 pci_read_config_word(dev, PCI_REG_VMCAP, ®);
589 if (BUS_RESTRICT_CAP(reg)) {
590 pci_read_config_word(dev, PCI_REG_VMCONFIG, ®);
591
592 switch (BUS_RESTRICT_CFG(reg)) {
593 case 0:
594 vmd->busn_start = 0;
595 break;
596 case 1:
597 vmd->busn_start = 128;
598 break;
599 case 2:
600 vmd->busn_start = 224;
601 break;
602 default:
603 pci_err(dev, "Unknown Bus Offset Setting (%d)\n",
604 BUS_RESTRICT_CFG(reg));
605 return -ENODEV;
606 }
607 }
608
609 return 0;
610 }
611
vmd_irq(int irq,void * data)612 static irqreturn_t vmd_irq(int irq, void *data)
613 {
614 struct vmd_irq_list *irqs = data;
615 struct vmd_irq *vmdirq;
616 int idx;
617
618 idx = srcu_read_lock(&irqs->srcu);
619 list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
620 generic_handle_irq(vmdirq->virq);
621 srcu_read_unlock(&irqs->srcu, idx);
622
623 return IRQ_HANDLED;
624 }
625
vmd_alloc_irqs(struct vmd_dev * vmd)626 static int vmd_alloc_irqs(struct vmd_dev *vmd)
627 {
628 struct pci_dev *dev = vmd->dev;
629 int i, err;
630
631 vmd->msix_count = pci_msix_vec_count(dev);
632 if (vmd->msix_count < 0)
633 return -ENODEV;
634
635 vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1,
636 vmd->msix_count, PCI_IRQ_MSIX);
637 if (vmd->msix_count < 0)
638 return vmd->msix_count;
639
640 vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
641 GFP_KERNEL);
642 if (!vmd->irqs)
643 return -ENOMEM;
644
645 for (i = 0; i < vmd->msix_count; i++) {
646 err = init_srcu_struct(&vmd->irqs[i].srcu);
647 if (err)
648 return err;
649
650 INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
651 err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
652 vmd_irq, IRQF_NO_THREAD,
653 "vmd", &vmd->irqs[i]);
654 if (err)
655 return err;
656 }
657
658 return 0;
659 }
660
vmd_enable_domain(struct vmd_dev * vmd,unsigned long features)661 static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
662 {
663 struct pci_sysdata *sd = &vmd->sysdata;
664 struct resource *res;
665 u32 upper_bits;
666 unsigned long flags;
667 LIST_HEAD(resources);
668 resource_size_t offset[2] = {0};
669 resource_size_t membar2_offset = 0x2000;
670 struct pci_bus *child;
671 int ret;
672
673 /*
674 * Shadow registers may exist in certain VMD device ids which allow
675 * guests to correctly assign host physical addresses to the root ports
676 * and child devices. These registers will either return the host value
677 * or 0, depending on an enable bit in the VMD device.
678 */
679 if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
680 membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
681 ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]);
682 if (ret)
683 return ret;
684 } else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
685 ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]);
686 if (ret)
687 return ret;
688 }
689
690 /*
691 * Certain VMD devices may have a root port configuration option which
692 * limits the bus range to between 0-127, 128-255, or 224-255
693 */
694 if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {
695 ret = vmd_get_bus_number_start(vmd);
696 if (ret)
697 return ret;
698 }
699
700 res = &vmd->dev->resource[VMD_CFGBAR];
701 vmd->resources[0] = (struct resource) {
702 .name = "VMD CFGBAR",
703 .start = vmd->busn_start,
704 .end = vmd->busn_start + (resource_size(res) >> 20) - 1,
705 .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
706 };
707
708 /*
709 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
710 * put 32-bit resources in the window.
711 *
712 * There's no hardware reason why a 64-bit window *couldn't*
713 * contain a 32-bit resource, but pbus_size_mem() computes the
714 * bridge window size assuming a 64-bit window will contain no
715 * 32-bit resources. __pci_assign_resource() enforces that
716 * artificial restriction to make sure everything will fit.
717 *
718 * The only way we could use a 64-bit non-prefetchable MEMBAR is
719 * if its address is <4GB so that we can convert it to a 32-bit
720 * resource. To be visible to the host OS, all VMD endpoints must
721 * be initially configured by platform BIOS, which includes setting
722 * up these resources. We can assume the device is configured
723 * according to the platform needs.
724 */
725 res = &vmd->dev->resource[VMD_MEMBAR1];
726 upper_bits = upper_32_bits(res->end);
727 flags = res->flags & ~IORESOURCE_SIZEALIGN;
728 if (!upper_bits)
729 flags &= ~IORESOURCE_MEM_64;
730 vmd->resources[1] = (struct resource) {
731 .name = "VMD MEMBAR1",
732 .start = res->start,
733 .end = res->end,
734 .flags = flags,
735 .parent = res,
736 };
737
738 res = &vmd->dev->resource[VMD_MEMBAR2];
739 upper_bits = upper_32_bits(res->end);
740 flags = res->flags & ~IORESOURCE_SIZEALIGN;
741 if (!upper_bits)
742 flags &= ~IORESOURCE_MEM_64;
743 vmd->resources[2] = (struct resource) {
744 .name = "VMD MEMBAR2",
745 .start = res->start + membar2_offset,
746 .end = res->end,
747 .flags = flags,
748 .parent = res,
749 };
750
751 sd->vmd_dev = vmd->dev;
752 sd->domain = vmd_find_free_domain();
753 if (sd->domain < 0)
754 return sd->domain;
755
756 sd->node = pcibus_to_node(vmd->dev->bus);
757
758 /*
759 * Currently MSI remapping must be enabled in guest passthrough mode
760 * due to some missing interrupt remapping plumbing. This is probably
761 * acceptable because the guest is usually CPU-limited and MSI
762 * remapping doesn't become a performance bottleneck.
763 */
764 if (!(features & VMD_FEAT_CAN_BYPASS_MSI_REMAP) ||
765 offset[0] || offset[1]) {
766 ret = vmd_alloc_irqs(vmd);
767 if (ret)
768 return ret;
769
770 vmd_set_msi_remapping(vmd, true);
771
772 ret = vmd_create_irq_domain(vmd);
773 if (ret)
774 return ret;
775
776 /*
777 * Override the IRQ domain bus token so the domain can be
778 * distinguished from a regular PCI/MSI domain.
779 */
780 irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI);
781 } else {
782 vmd_set_msi_remapping(vmd, false);
783 }
784
785 pci_add_resource(&resources, &vmd->resources[0]);
786 pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);
787 pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]);
788
789 vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start,
790 &vmd_ops, sd, &resources);
791 if (!vmd->bus) {
792 pci_free_resource_list(&resources);
793 vmd_remove_irq_domain(vmd);
794 return -ENODEV;
795 }
796
797 vmd_attach_resources(vmd);
798 if (vmd->irq_domain)
799 dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
800
801 vmd_acpi_begin();
802
803 pci_scan_child_bus(vmd->bus);
804 pci_assign_unassigned_bus_resources(vmd->bus);
805
806 /*
807 * VMD root buses are virtual and don't return true on pci_is_pcie()
808 * and will fail pcie_bus_configure_settings() early. It can instead be
809 * run on each of the real root ports.
810 */
811 list_for_each_entry(child, &vmd->bus->children, node)
812 pcie_bus_configure_settings(child);
813
814 pci_bus_add_devices(vmd->bus);
815
816 vmd_acpi_end();
817
818 WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
819 "domain"), "Can't create symlink to domain\n");
820 return 0;
821 }
822
vmd_probe(struct pci_dev * dev,const struct pci_device_id * id)823 static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
824 {
825 unsigned long features = (unsigned long) id->driver_data;
826 struct vmd_dev *vmd;
827 int err;
828
829 if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
830 return -ENOMEM;
831
832 vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
833 if (!vmd)
834 return -ENOMEM;
835
836 vmd->dev = dev;
837 err = pcim_enable_device(dev);
838 if (err < 0)
839 return err;
840
841 vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
842 if (!vmd->cfgbar)
843 return -ENOMEM;
844
845 pci_set_master(dev);
846 if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
847 dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
848 return -ENODEV;
849
850 if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
851 vmd->first_vec = 1;
852
853 spin_lock_init(&vmd->cfg_lock);
854 pci_set_drvdata(dev, vmd);
855 err = vmd_enable_domain(vmd, features);
856 if (err)
857 return err;
858
859 dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
860 vmd->sysdata.domain);
861 return 0;
862 }
863
vmd_cleanup_srcu(struct vmd_dev * vmd)864 static void vmd_cleanup_srcu(struct vmd_dev *vmd)
865 {
866 int i;
867
868 for (i = 0; i < vmd->msix_count; i++)
869 cleanup_srcu_struct(&vmd->irqs[i].srcu);
870 }
871
vmd_remove(struct pci_dev * dev)872 static void vmd_remove(struct pci_dev *dev)
873 {
874 struct vmd_dev *vmd = pci_get_drvdata(dev);
875
876 sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
877 pci_stop_root_bus(vmd->bus);
878 pci_remove_root_bus(vmd->bus);
879 vmd_cleanup_srcu(vmd);
880 vmd_detach_resources(vmd);
881 vmd_remove_irq_domain(vmd);
882 }
883
vmd_shutdown(struct pci_dev * dev)884 static void vmd_shutdown(struct pci_dev *dev)
885 {
886 struct vmd_dev *vmd = pci_get_drvdata(dev);
887
888 vmd_remove_irq_domain(vmd);
889 }
890
891 #ifdef CONFIG_PM_SLEEP
vmd_suspend(struct device * dev)892 static int vmd_suspend(struct device *dev)
893 {
894 struct pci_dev *pdev = to_pci_dev(dev);
895 struct vmd_dev *vmd = pci_get_drvdata(pdev);
896 int i;
897
898 for (i = 0; i < vmd->msix_count; i++)
899 devm_free_irq(dev, pci_irq_vector(pdev, i), &vmd->irqs[i]);
900
901 return 0;
902 }
903
vmd_resume(struct device * dev)904 static int vmd_resume(struct device *dev)
905 {
906 struct pci_dev *pdev = to_pci_dev(dev);
907 struct vmd_dev *vmd = pci_get_drvdata(pdev);
908 int err, i;
909
910 if (vmd->irq_domain)
911 vmd_set_msi_remapping(vmd, true);
912 else
913 vmd_set_msi_remapping(vmd, false);
914
915 for (i = 0; i < vmd->msix_count; i++) {
916 err = devm_request_irq(dev, pci_irq_vector(pdev, i),
917 vmd_irq, IRQF_NO_THREAD,
918 "vmd", &vmd->irqs[i]);
919 if (err)
920 return err;
921 }
922
923 return 0;
924 }
925 #endif
926 static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
927
928 static const struct pci_device_id vmd_ids[] = {
929 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_201D),
930 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP,},
931 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0),
932 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW |
933 VMD_FEAT_HAS_BUS_RESTRICTIONS |
934 VMD_FEAT_CAN_BYPASS_MSI_REMAP,},
935 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x467f),
936 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
937 VMD_FEAT_HAS_BUS_RESTRICTIONS |
938 VMD_FEAT_OFFSET_FIRST_VECTOR,},
939 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x4c3d),
940 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
941 VMD_FEAT_HAS_BUS_RESTRICTIONS |
942 VMD_FEAT_OFFSET_FIRST_VECTOR,},
943 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
944 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
945 VMD_FEAT_HAS_BUS_RESTRICTIONS |
946 VMD_FEAT_OFFSET_FIRST_VECTOR,},
947 {0,}
948 };
949 MODULE_DEVICE_TABLE(pci, vmd_ids);
950
951 static struct pci_driver vmd_drv = {
952 .name = "vmd",
953 .id_table = vmd_ids,
954 .probe = vmd_probe,
955 .remove = vmd_remove,
956 .shutdown = vmd_shutdown,
957 .driver = {
958 .pm = &vmd_dev_pm_ops,
959 },
960 };
961 module_pci_driver(vmd_drv);
962
963 MODULE_AUTHOR("Intel Corporation");
964 MODULE_LICENSE("GPL v2");
965 MODULE_VERSION("0.6");
966