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
37 enum vmd_features {
38 /*
39 * Device may contain registers which hint the physical location of the
40 * membars, in order to allow proper address translation during
41 * resource assignment to enable guest virtualization
42 */
43 VMD_FEAT_HAS_MEMBAR_SHADOW = (1 << 0),
44
45 /*
46 * Device may provide root port configuration information which limits
47 * bus numbering
48 */
49 VMD_FEAT_HAS_BUS_RESTRICTIONS = (1 << 1),
50
51 /*
52 * Device contains physical location shadow registers in
53 * vendor-specific capability space
54 */
55 VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP = (1 << 2),
56
57 /*
58 * Device may use MSI-X vector 0 for software triggering and will not
59 * be used for MSI remapping
60 */
61 VMD_FEAT_OFFSET_FIRST_VECTOR = (1 << 3),
62
63 /*
64 * 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 /*
71 * Enable ASPM on the PCIE root ports and set the default LTR of the
72 * storage devices on platforms where these values are not configured by
73 * BIOS. This is needed for laptops, which require these settings for
74 * proper power management of the SoC.
75 */
76 VMD_FEAT_BIOS_PM_QUIRK = (1 << 5),
77 };
78
79 #define VMD_BIOS_PM_QUIRK_LTR 0x1003 /* 3145728 ns */
80
81 #define VMD_FEATS_CLIENT (VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP | \
82 VMD_FEAT_HAS_BUS_RESTRICTIONS | \
83 VMD_FEAT_OFFSET_FIRST_VECTOR | \
84 VMD_FEAT_BIOS_PM_QUIRK)
85
86 static DEFINE_IDA(vmd_instance_ida);
87
88 /*
89 * Lock for manipulating VMD IRQ lists.
90 */
91 static DEFINE_RAW_SPINLOCK(list_lock);
92
93 /**
94 * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
95 * @node: list item for parent traversal.
96 * @irq: back pointer to parent.
97 * @enabled: true if driver enabled IRQ
98 * @virq: the virtual IRQ value provided to the requesting driver.
99 *
100 * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
101 * a VMD IRQ using this structure.
102 */
103 struct vmd_irq {
104 struct list_head node;
105 struct vmd_irq_list *irq;
106 bool enabled;
107 unsigned int virq;
108 };
109
110 /**
111 * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
112 * @irq_list: the list of irq's the VMD one demuxes to.
113 * @srcu: SRCU struct for local synchronization.
114 * @count: number of child IRQs assigned to this vector; used to track
115 * sharing.
116 * @virq: The underlying VMD Linux interrupt number
117 */
118 struct vmd_irq_list {
119 struct list_head irq_list;
120 struct srcu_struct srcu;
121 unsigned int count;
122 unsigned int virq;
123 };
124
125 struct vmd_dev {
126 struct pci_dev *dev;
127
128 spinlock_t cfg_lock;
129 void __iomem *cfgbar;
130
131 int msix_count;
132 struct vmd_irq_list *irqs;
133
134 struct pci_sysdata sysdata;
135 struct resource resources[3];
136 struct irq_domain *irq_domain;
137 struct pci_bus *bus;
138 u8 busn_start;
139 u8 first_vec;
140 char *name;
141 int instance;
142 };
143
vmd_from_bus(struct pci_bus * bus)144 static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
145 {
146 return container_of(bus->sysdata, struct vmd_dev, sysdata);
147 }
148
index_from_irqs(struct vmd_dev * vmd,struct vmd_irq_list * irqs)149 static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
150 struct vmd_irq_list *irqs)
151 {
152 return irqs - vmd->irqs;
153 }
154
155 /*
156 * Drivers managing a device in a VMD domain allocate their own IRQs as before,
157 * but the MSI entry for the hardware it's driving will be programmed with a
158 * destination ID for the VMD MSI-X table. The VMD muxes interrupts in its
159 * domain into one of its own, and the VMD driver de-muxes these for the
160 * handlers sharing that VMD IRQ. The vmd irq_domain provides the operations
161 * and irq_chip to set this up.
162 */
vmd_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)163 static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
164 {
165 struct vmd_irq *vmdirq = data->chip_data;
166 struct vmd_irq_list *irq = vmdirq->irq;
167 struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
168
169 memset(msg, 0, sizeof(*msg));
170 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
171 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
172 msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq);
173 }
174
175 /*
176 * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
177 */
vmd_irq_enable(struct irq_data * data)178 static void vmd_irq_enable(struct irq_data *data)
179 {
180 struct vmd_irq *vmdirq = data->chip_data;
181 unsigned long flags;
182
183 raw_spin_lock_irqsave(&list_lock, flags);
184 WARN_ON(vmdirq->enabled);
185 list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
186 vmdirq->enabled = true;
187 raw_spin_unlock_irqrestore(&list_lock, flags);
188
189 data->chip->irq_unmask(data);
190 }
191
vmd_irq_disable(struct irq_data * data)192 static void vmd_irq_disable(struct irq_data *data)
193 {
194 struct vmd_irq *vmdirq = data->chip_data;
195 unsigned long flags;
196
197 data->chip->irq_mask(data);
198
199 raw_spin_lock_irqsave(&list_lock, flags);
200 if (vmdirq->enabled) {
201 list_del_rcu(&vmdirq->node);
202 vmdirq->enabled = false;
203 }
204 raw_spin_unlock_irqrestore(&list_lock, flags);
205 }
206
207 /*
208 * XXX: Stubbed until we develop acceptable way to not create conflicts with
209 * other devices sharing the same vector.
210 */
vmd_irq_set_affinity(struct irq_data * data,const struct cpumask * dest,bool force)211 static int vmd_irq_set_affinity(struct irq_data *data,
212 const struct cpumask *dest, bool force)
213 {
214 return -EINVAL;
215 }
216
217 static struct irq_chip vmd_msi_controller = {
218 .name = "VMD-MSI",
219 .irq_enable = vmd_irq_enable,
220 .irq_disable = vmd_irq_disable,
221 .irq_compose_msi_msg = vmd_compose_msi_msg,
222 .irq_set_affinity = vmd_irq_set_affinity,
223 };
224
vmd_get_hwirq(struct msi_domain_info * info,msi_alloc_info_t * arg)225 static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
226 msi_alloc_info_t *arg)
227 {
228 return 0;
229 }
230
231 /*
232 * XXX: We can be even smarter selecting the best IRQ once we solve the
233 * affinity problem.
234 */
vmd_next_irq(struct vmd_dev * vmd,struct msi_desc * desc)235 static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
236 {
237 unsigned long flags;
238 int i, best;
239
240 if (vmd->msix_count == 1 + vmd->first_vec)
241 return &vmd->irqs[vmd->first_vec];
242
243 /*
244 * White list for fast-interrupt handlers. All others will share the
245 * "slow" interrupt vector.
246 */
247 switch (msi_desc_to_pci_dev(desc)->class) {
248 case PCI_CLASS_STORAGE_EXPRESS:
249 break;
250 default:
251 return &vmd->irqs[vmd->first_vec];
252 }
253
254 raw_spin_lock_irqsave(&list_lock, flags);
255 best = vmd->first_vec + 1;
256 for (i = best; i < vmd->msix_count; i++)
257 if (vmd->irqs[i].count < vmd->irqs[best].count)
258 best = i;
259 vmd->irqs[best].count++;
260 raw_spin_unlock_irqrestore(&list_lock, flags);
261
262 return &vmd->irqs[best];
263 }
264
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)265 static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
266 unsigned int virq, irq_hw_number_t hwirq,
267 msi_alloc_info_t *arg)
268 {
269 struct msi_desc *desc = arg->desc;
270 struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
271 struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
272
273 if (!vmdirq)
274 return -ENOMEM;
275
276 INIT_LIST_HEAD(&vmdirq->node);
277 vmdirq->irq = vmd_next_irq(vmd, desc);
278 vmdirq->virq = virq;
279
280 irq_domain_set_info(domain, virq, vmdirq->irq->virq, info->chip, vmdirq,
281 handle_untracked_irq, vmd, NULL);
282 return 0;
283 }
284
vmd_msi_free(struct irq_domain * domain,struct msi_domain_info * info,unsigned int virq)285 static void vmd_msi_free(struct irq_domain *domain,
286 struct msi_domain_info *info, unsigned int virq)
287 {
288 struct vmd_irq *vmdirq = irq_get_chip_data(virq);
289 unsigned long flags;
290
291 synchronize_srcu(&vmdirq->irq->srcu);
292
293 /* XXX: Potential optimization to rebalance */
294 raw_spin_lock_irqsave(&list_lock, flags);
295 vmdirq->irq->count--;
296 raw_spin_unlock_irqrestore(&list_lock, flags);
297
298 kfree(vmdirq);
299 }
300
vmd_msi_prepare(struct irq_domain * domain,struct device * dev,int nvec,msi_alloc_info_t * arg)301 static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
302 int nvec, msi_alloc_info_t *arg)
303 {
304 struct pci_dev *pdev = to_pci_dev(dev);
305 struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
306
307 if (nvec > vmd->msix_count)
308 return vmd->msix_count;
309
310 memset(arg, 0, sizeof(*arg));
311 return 0;
312 }
313
vmd_set_desc(msi_alloc_info_t * arg,struct msi_desc * desc)314 static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
315 {
316 arg->desc = desc;
317 }
318
319 static struct msi_domain_ops vmd_msi_domain_ops = {
320 .get_hwirq = vmd_get_hwirq,
321 .msi_init = vmd_msi_init,
322 .msi_free = vmd_msi_free,
323 .msi_prepare = vmd_msi_prepare,
324 .set_desc = vmd_set_desc,
325 };
326
327 static struct msi_domain_info vmd_msi_domain_info = {
328 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
329 MSI_FLAG_PCI_MSIX,
330 .ops = &vmd_msi_domain_ops,
331 .chip = &vmd_msi_controller,
332 };
333
vmd_set_msi_remapping(struct vmd_dev * vmd,bool enable)334 static void vmd_set_msi_remapping(struct vmd_dev *vmd, bool enable)
335 {
336 u16 reg;
337
338 pci_read_config_word(vmd->dev, PCI_REG_VMCONFIG, ®);
339 reg = enable ? (reg & ~VMCONFIG_MSI_REMAP) :
340 (reg | VMCONFIG_MSI_REMAP);
341 pci_write_config_word(vmd->dev, PCI_REG_VMCONFIG, reg);
342 }
343
vmd_create_irq_domain(struct vmd_dev * vmd)344 static int vmd_create_irq_domain(struct vmd_dev *vmd)
345 {
346 struct fwnode_handle *fn;
347
348 fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
349 if (!fn)
350 return -ENODEV;
351
352 vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL);
353 if (!vmd->irq_domain) {
354 irq_domain_free_fwnode(fn);
355 return -ENODEV;
356 }
357
358 return 0;
359 }
360
vmd_remove_irq_domain(struct vmd_dev * vmd)361 static void vmd_remove_irq_domain(struct vmd_dev *vmd)
362 {
363 /*
364 * Some production BIOS won't enable remapping between soft reboots.
365 * Ensure remapping is restored before unloading the driver.
366 */
367 if (!vmd->msix_count)
368 vmd_set_msi_remapping(vmd, true);
369
370 if (vmd->irq_domain) {
371 struct fwnode_handle *fn = vmd->irq_domain->fwnode;
372
373 irq_domain_remove(vmd->irq_domain);
374 irq_domain_free_fwnode(fn);
375 }
376 }
377
vmd_cfg_addr(struct vmd_dev * vmd,struct pci_bus * bus,unsigned int devfn,int reg,int len)378 static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
379 unsigned int devfn, int reg, int len)
380 {
381 unsigned int busnr_ecam = bus->number - vmd->busn_start;
382 u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
383
384 if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR]))
385 return NULL;
386
387 return vmd->cfgbar + offset;
388 }
389
390 /*
391 * CPU may deadlock if config space is not serialized on some versions of this
392 * hardware, so all config space access is done under a spinlock.
393 */
vmd_pci_read(struct pci_bus * bus,unsigned int devfn,int reg,int len,u32 * value)394 static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
395 int len, u32 *value)
396 {
397 struct vmd_dev *vmd = vmd_from_bus(bus);
398 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
399 unsigned long flags;
400 int ret = 0;
401
402 if (!addr)
403 return -EFAULT;
404
405 spin_lock_irqsave(&vmd->cfg_lock, flags);
406 switch (len) {
407 case 1:
408 *value = readb(addr);
409 break;
410 case 2:
411 *value = readw(addr);
412 break;
413 case 4:
414 *value = readl(addr);
415 break;
416 default:
417 ret = -EINVAL;
418 break;
419 }
420 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
421 return ret;
422 }
423
424 /*
425 * VMD h/w converts non-posted config writes to posted memory writes. The
426 * read-back in this function forces the completion so it returns only after
427 * the config space was written, as expected.
428 */
vmd_pci_write(struct pci_bus * bus,unsigned int devfn,int reg,int len,u32 value)429 static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
430 int len, u32 value)
431 {
432 struct vmd_dev *vmd = vmd_from_bus(bus);
433 void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
434 unsigned long flags;
435 int ret = 0;
436
437 if (!addr)
438 return -EFAULT;
439
440 spin_lock_irqsave(&vmd->cfg_lock, flags);
441 switch (len) {
442 case 1:
443 writeb(value, addr);
444 readb(addr);
445 break;
446 case 2:
447 writew(value, addr);
448 readw(addr);
449 break;
450 case 4:
451 writel(value, addr);
452 readl(addr);
453 break;
454 default:
455 ret = -EINVAL;
456 break;
457 }
458 spin_unlock_irqrestore(&vmd->cfg_lock, flags);
459 return ret;
460 }
461
462 static struct pci_ops vmd_ops = {
463 .read = vmd_pci_read,
464 .write = vmd_pci_write,
465 };
466
467 #ifdef CONFIG_ACPI
vmd_acpi_find_companion(struct pci_dev * pci_dev)468 static struct acpi_device *vmd_acpi_find_companion(struct pci_dev *pci_dev)
469 {
470 struct pci_host_bridge *bridge;
471 u32 busnr, addr;
472
473 if (pci_dev->bus->ops != &vmd_ops)
474 return NULL;
475
476 bridge = pci_find_host_bridge(pci_dev->bus);
477 busnr = pci_dev->bus->number - bridge->bus->number;
478 /*
479 * The address computation below is only applicable to relative bus
480 * numbers below 32.
481 */
482 if (busnr > 31)
483 return NULL;
484
485 addr = (busnr << 24) | ((u32)pci_dev->devfn << 16) | 0x8000FFFFU;
486
487 dev_dbg(&pci_dev->dev, "Looking for ACPI companion (address 0x%x)\n",
488 addr);
489
490 return acpi_find_child_device(ACPI_COMPANION(bridge->dev.parent), addr,
491 false);
492 }
493
494 static bool hook_installed;
495
vmd_acpi_begin(void)496 static void vmd_acpi_begin(void)
497 {
498 if (pci_acpi_set_companion_lookup_hook(vmd_acpi_find_companion))
499 return;
500
501 hook_installed = true;
502 }
503
vmd_acpi_end(void)504 static void vmd_acpi_end(void)
505 {
506 if (!hook_installed)
507 return;
508
509 pci_acpi_clear_companion_lookup_hook();
510 hook_installed = false;
511 }
512 #else
vmd_acpi_begin(void)513 static inline void vmd_acpi_begin(void) { }
vmd_acpi_end(void)514 static inline void vmd_acpi_end(void) { }
515 #endif /* CONFIG_ACPI */
516
vmd_domain_reset(struct vmd_dev * vmd)517 static void vmd_domain_reset(struct vmd_dev *vmd)
518 {
519 u16 bus, max_buses = resource_size(&vmd->resources[0]);
520 u8 dev, functions, fn, hdr_type;
521 char __iomem *base;
522
523 for (bus = 0; bus < max_buses; bus++) {
524 for (dev = 0; dev < 32; dev++) {
525 base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus,
526 PCI_DEVFN(dev, 0), 0);
527
528 hdr_type = readb(base + PCI_HEADER_TYPE);
529
530 functions = (hdr_type & 0x80) ? 8 : 1;
531 for (fn = 0; fn < functions; fn++) {
532 base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus,
533 PCI_DEVFN(dev, fn), 0);
534
535 hdr_type = readb(base + PCI_HEADER_TYPE) &
536 PCI_HEADER_TYPE_MASK;
537
538 if (hdr_type != PCI_HEADER_TYPE_BRIDGE ||
539 (readw(base + PCI_CLASS_DEVICE) !=
540 PCI_CLASS_BRIDGE_PCI))
541 continue;
542
543 /*
544 * Temporarily disable the I/O range before updating
545 * PCI_IO_BASE.
546 */
547 writel(0x0000ffff, base + PCI_IO_BASE_UPPER16);
548 /* Update lower 16 bits of I/O base/limit */
549 writew(0x00f0, base + PCI_IO_BASE);
550 /* Update upper 16 bits of I/O base/limit */
551 writel(0, base + PCI_IO_BASE_UPPER16);
552
553 /* MMIO Base/Limit */
554 writel(0x0000fff0, base + PCI_MEMORY_BASE);
555
556 /* Prefetchable MMIO Base/Limit */
557 writel(0, base + PCI_PREF_LIMIT_UPPER32);
558 writel(0x0000fff0, base + PCI_PREF_MEMORY_BASE);
559 writel(0xffffffff, base + PCI_PREF_BASE_UPPER32);
560 }
561 }
562 }
563 }
564
vmd_attach_resources(struct vmd_dev * vmd)565 static void vmd_attach_resources(struct vmd_dev *vmd)
566 {
567 vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
568 vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
569 }
570
vmd_detach_resources(struct vmd_dev * vmd)571 static void vmd_detach_resources(struct vmd_dev *vmd)
572 {
573 vmd->dev->resource[VMD_MEMBAR1].child = NULL;
574 vmd->dev->resource[VMD_MEMBAR2].child = NULL;
575 }
576
577 /*
578 * VMD domains start at 0x10000 to not clash with ACPI _SEG domains.
579 * Per ACPI r6.0, sec 6.5.6, _SEG returns an integer, of which the lower
580 * 16 bits are the PCI Segment Group (domain) number. Other bits are
581 * currently reserved.
582 */
vmd_find_free_domain(void)583 static int vmd_find_free_domain(void)
584 {
585 int domain = 0xffff;
586 struct pci_bus *bus = NULL;
587
588 while ((bus = pci_find_next_bus(bus)) != NULL)
589 domain = max_t(int, domain, pci_domain_nr(bus));
590 return domain + 1;
591 }
592
vmd_get_phys_offsets(struct vmd_dev * vmd,bool native_hint,resource_size_t * offset1,resource_size_t * offset2)593 static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
594 resource_size_t *offset1,
595 resource_size_t *offset2)
596 {
597 struct pci_dev *dev = vmd->dev;
598 u64 phys1, phys2;
599
600 if (native_hint) {
601 u32 vmlock;
602 int ret;
603
604 ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
605 if (ret || PCI_POSSIBLE_ERROR(vmlock))
606 return -ENODEV;
607
608 if (MB2_SHADOW_EN(vmlock)) {
609 void __iomem *membar2;
610
611 membar2 = pci_iomap(dev, VMD_MEMBAR2, 0);
612 if (!membar2)
613 return -ENOMEM;
614 phys1 = readq(membar2 + MB2_SHADOW_OFFSET);
615 phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8);
616 pci_iounmap(dev, membar2);
617 } else
618 return 0;
619 } else {
620 /* Hypervisor-Emulated Vendor-Specific Capability */
621 int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
622 u32 reg, regu;
623
624 pci_read_config_dword(dev, pos + 4, ®);
625
626 /* "SHDW" */
627 if (pos && reg == 0x53484457) {
628 pci_read_config_dword(dev, pos + 8, ®);
629 pci_read_config_dword(dev, pos + 12, ®u);
630 phys1 = (u64) regu << 32 | reg;
631
632 pci_read_config_dword(dev, pos + 16, ®);
633 pci_read_config_dword(dev, pos + 20, ®u);
634 phys2 = (u64) regu << 32 | reg;
635 } else
636 return 0;
637 }
638
639 *offset1 = dev->resource[VMD_MEMBAR1].start -
640 (phys1 & PCI_BASE_ADDRESS_MEM_MASK);
641 *offset2 = dev->resource[VMD_MEMBAR2].start -
642 (phys2 & PCI_BASE_ADDRESS_MEM_MASK);
643
644 return 0;
645 }
646
vmd_get_bus_number_start(struct vmd_dev * vmd)647 static int vmd_get_bus_number_start(struct vmd_dev *vmd)
648 {
649 struct pci_dev *dev = vmd->dev;
650 u16 reg;
651
652 pci_read_config_word(dev, PCI_REG_VMCAP, ®);
653 if (BUS_RESTRICT_CAP(reg)) {
654 pci_read_config_word(dev, PCI_REG_VMCONFIG, ®);
655
656 switch (BUS_RESTRICT_CFG(reg)) {
657 case 0:
658 vmd->busn_start = 0;
659 break;
660 case 1:
661 vmd->busn_start = 128;
662 break;
663 case 2:
664 vmd->busn_start = 224;
665 break;
666 default:
667 pci_err(dev, "Unknown Bus Offset Setting (%d)\n",
668 BUS_RESTRICT_CFG(reg));
669 return -ENODEV;
670 }
671 }
672
673 return 0;
674 }
675
vmd_irq(int irq,void * data)676 static irqreturn_t vmd_irq(int irq, void *data)
677 {
678 struct vmd_irq_list *irqs = data;
679 struct vmd_irq *vmdirq;
680 int idx;
681
682 idx = srcu_read_lock(&irqs->srcu);
683 list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
684 generic_handle_irq(vmdirq->virq);
685 srcu_read_unlock(&irqs->srcu, idx);
686
687 return IRQ_HANDLED;
688 }
689
vmd_alloc_irqs(struct vmd_dev * vmd)690 static int vmd_alloc_irqs(struct vmd_dev *vmd)
691 {
692 struct pci_dev *dev = vmd->dev;
693 int i, err;
694
695 vmd->msix_count = pci_msix_vec_count(dev);
696 if (vmd->msix_count < 0)
697 return -ENODEV;
698
699 vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1,
700 vmd->msix_count, PCI_IRQ_MSIX);
701 if (vmd->msix_count < 0)
702 return vmd->msix_count;
703
704 vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
705 GFP_KERNEL);
706 if (!vmd->irqs)
707 return -ENOMEM;
708
709 for (i = 0; i < vmd->msix_count; i++) {
710 err = init_srcu_struct(&vmd->irqs[i].srcu);
711 if (err)
712 return err;
713
714 INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
715 vmd->irqs[i].virq = pci_irq_vector(dev, i);
716 err = devm_request_irq(&dev->dev, vmd->irqs[i].virq,
717 vmd_irq, IRQF_NO_THREAD,
718 vmd->name, &vmd->irqs[i]);
719 if (err)
720 return err;
721 }
722
723 return 0;
724 }
725
726 /*
727 * Since VMD is an aperture to regular PCIe root ports, only allow it to
728 * control features that the OS is allowed to control on the physical PCI bus.
729 */
vmd_copy_host_bridge_flags(struct pci_host_bridge * root_bridge,struct pci_host_bridge * vmd_bridge)730 static void vmd_copy_host_bridge_flags(struct pci_host_bridge *root_bridge,
731 struct pci_host_bridge *vmd_bridge)
732 {
733 vmd_bridge->native_pcie_hotplug = root_bridge->native_pcie_hotplug;
734 vmd_bridge->native_shpc_hotplug = root_bridge->native_shpc_hotplug;
735 vmd_bridge->native_aer = root_bridge->native_aer;
736 vmd_bridge->native_pme = root_bridge->native_pme;
737 vmd_bridge->native_ltr = root_bridge->native_ltr;
738 vmd_bridge->native_dpc = root_bridge->native_dpc;
739 }
740
741 /*
742 * Enable ASPM and LTR settings on devices that aren't configured by BIOS.
743 */
vmd_pm_enable_quirk(struct pci_dev * pdev,void * userdata)744 static int vmd_pm_enable_quirk(struct pci_dev *pdev, void *userdata)
745 {
746 unsigned long features = *(unsigned long *)userdata;
747 u16 ltr = VMD_BIOS_PM_QUIRK_LTR;
748 u32 ltr_reg;
749 int pos;
750
751 if (!(features & VMD_FEAT_BIOS_PM_QUIRK))
752 return 0;
753
754 pci_enable_link_state_locked(pdev, PCIE_LINK_STATE_ALL);
755
756 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_LTR);
757 if (!pos)
758 return 0;
759
760 /*
761 * Skip if the max snoop LTR is non-zero, indicating BIOS has set it
762 * so the LTR quirk is not needed.
763 */
764 pci_read_config_dword(pdev, pos + PCI_LTR_MAX_SNOOP_LAT, <r_reg);
765 if (!!(ltr_reg & (PCI_LTR_VALUE_MASK | PCI_LTR_SCALE_MASK)))
766 return 0;
767
768 /*
769 * Set the default values to the maximum required by the platform to
770 * allow the deepest power management savings. Write as a DWORD where
771 * the lower word is the max snoop latency and the upper word is the
772 * max non-snoop latency.
773 */
774 ltr_reg = (ltr << 16) | ltr;
775 pci_write_config_dword(pdev, pos + PCI_LTR_MAX_SNOOP_LAT, ltr_reg);
776 pci_info(pdev, "VMD: Default LTR value set by driver\n");
777
778 return 0;
779 }
780
vmd_enable_domain(struct vmd_dev * vmd,unsigned long features)781 static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
782 {
783 struct pci_sysdata *sd = &vmd->sysdata;
784 struct resource *res;
785 u32 upper_bits;
786 unsigned long flags;
787 LIST_HEAD(resources);
788 resource_size_t offset[2] = {0};
789 resource_size_t membar2_offset = 0x2000;
790 struct pci_bus *child;
791 struct pci_dev *dev;
792 int ret;
793
794 /*
795 * Shadow registers may exist in certain VMD device ids which allow
796 * guests to correctly assign host physical addresses to the root ports
797 * and child devices. These registers will either return the host value
798 * or 0, depending on an enable bit in the VMD device.
799 */
800 if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
801 membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
802 ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]);
803 if (ret)
804 return ret;
805 } else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
806 ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]);
807 if (ret)
808 return ret;
809 }
810
811 /*
812 * Certain VMD devices may have a root port configuration option which
813 * limits the bus range to between 0-127, 128-255, or 224-255
814 */
815 if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {
816 ret = vmd_get_bus_number_start(vmd);
817 if (ret)
818 return ret;
819 }
820
821 res = &vmd->dev->resource[VMD_CFGBAR];
822 vmd->resources[0] = (struct resource) {
823 .name = "VMD CFGBAR",
824 .start = vmd->busn_start,
825 .end = vmd->busn_start + (resource_size(res) >> 20) - 1,
826 .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
827 };
828
829 /*
830 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
831 * put 32-bit resources in the window.
832 *
833 * There's no hardware reason why a 64-bit window *couldn't*
834 * contain a 32-bit resource, but pbus_size_mem() computes the
835 * bridge window size assuming a 64-bit window will contain no
836 * 32-bit resources. __pci_assign_resource() enforces that
837 * artificial restriction to make sure everything will fit.
838 *
839 * The only way we could use a 64-bit non-prefetchable MEMBAR is
840 * if its address is <4GB so that we can convert it to a 32-bit
841 * resource. To be visible to the host OS, all VMD endpoints must
842 * be initially configured by platform BIOS, which includes setting
843 * up these resources. We can assume the device is configured
844 * according to the platform needs.
845 */
846 res = &vmd->dev->resource[VMD_MEMBAR1];
847 upper_bits = upper_32_bits(res->end);
848 flags = res->flags & ~IORESOURCE_SIZEALIGN;
849 if (!upper_bits)
850 flags &= ~IORESOURCE_MEM_64;
851 vmd->resources[1] = (struct resource) {
852 .name = "VMD MEMBAR1",
853 .start = res->start,
854 .end = res->end,
855 .flags = flags,
856 .parent = res,
857 };
858
859 res = &vmd->dev->resource[VMD_MEMBAR2];
860 upper_bits = upper_32_bits(res->end);
861 flags = res->flags & ~IORESOURCE_SIZEALIGN;
862 if (!upper_bits)
863 flags &= ~IORESOURCE_MEM_64;
864 vmd->resources[2] = (struct resource) {
865 .name = "VMD MEMBAR2",
866 .start = res->start + membar2_offset,
867 .end = res->end,
868 .flags = flags,
869 .parent = res,
870 };
871
872 sd->vmd_dev = vmd->dev;
873 sd->domain = vmd_find_free_domain();
874 if (sd->domain < 0)
875 return sd->domain;
876
877 sd->node = pcibus_to_node(vmd->dev->bus);
878
879 /*
880 * Currently MSI remapping must be enabled in guest passthrough mode
881 * due to some missing interrupt remapping plumbing. This is probably
882 * acceptable because the guest is usually CPU-limited and MSI
883 * remapping doesn't become a performance bottleneck.
884 */
885 if (!(features & VMD_FEAT_CAN_BYPASS_MSI_REMAP) ||
886 offset[0] || offset[1]) {
887 ret = vmd_alloc_irqs(vmd);
888 if (ret)
889 return ret;
890
891 vmd_set_msi_remapping(vmd, true);
892
893 ret = vmd_create_irq_domain(vmd);
894 if (ret)
895 return ret;
896
897 /*
898 * Override the IRQ domain bus token so the domain can be
899 * distinguished from a regular PCI/MSI domain.
900 */
901 irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI);
902 } else {
903 vmd_set_msi_remapping(vmd, false);
904 }
905
906 pci_add_resource(&resources, &vmd->resources[0]);
907 pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]);
908 pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]);
909
910 vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start,
911 &vmd_ops, sd, &resources);
912 if (!vmd->bus) {
913 pci_free_resource_list(&resources);
914 vmd_remove_irq_domain(vmd);
915 return -ENODEV;
916 }
917
918 vmd_copy_host_bridge_flags(pci_find_host_bridge(vmd->dev->bus),
919 to_pci_host_bridge(vmd->bus->bridge));
920
921 vmd_attach_resources(vmd);
922 if (vmd->irq_domain)
923 dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
924 else
925 dev_set_msi_domain(&vmd->bus->dev,
926 dev_get_msi_domain(&vmd->dev->dev));
927
928 vmd_acpi_begin();
929
930 pci_scan_child_bus(vmd->bus);
931 vmd_domain_reset(vmd);
932
933 /* When Intel VMD is enabled, the OS does not discover the Root Ports
934 * owned by Intel VMD within the MMCFG space. pci_reset_bus() applies
935 * a reset to the parent of the PCI device supplied as argument. This
936 * is why we pass a child device, so the reset can be triggered at
937 * the Intel bridge level and propagated to all the children in the
938 * hierarchy.
939 */
940 list_for_each_entry(child, &vmd->bus->children, node) {
941 if (!list_empty(&child->devices)) {
942 dev = list_first_entry(&child->devices,
943 struct pci_dev, bus_list);
944 ret = pci_reset_bus(dev);
945 if (ret)
946 pci_warn(dev, "can't reset device: %d\n", ret);
947
948 break;
949 }
950 }
951
952 pci_assign_unassigned_bus_resources(vmd->bus);
953
954 pci_walk_bus(vmd->bus, vmd_pm_enable_quirk, &features);
955
956 /*
957 * VMD root buses are virtual and don't return true on pci_is_pcie()
958 * and will fail pcie_bus_configure_settings() early. It can instead be
959 * run on each of the real root ports.
960 */
961 list_for_each_entry(child, &vmd->bus->children, node)
962 pcie_bus_configure_settings(child);
963
964 pci_bus_add_devices(vmd->bus);
965
966 vmd_acpi_end();
967
968 WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
969 "domain"), "Can't create symlink to domain\n");
970 return 0;
971 }
972
vmd_probe(struct pci_dev * dev,const struct pci_device_id * id)973 static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
974 {
975 unsigned long features = (unsigned long) id->driver_data;
976 struct vmd_dev *vmd;
977 int err;
978
979 if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
980 return -ENOMEM;
981
982 vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
983 if (!vmd)
984 return -ENOMEM;
985
986 vmd->dev = dev;
987 vmd->instance = ida_simple_get(&vmd_instance_ida, 0, 0, GFP_KERNEL);
988 if (vmd->instance < 0)
989 return vmd->instance;
990
991 vmd->name = devm_kasprintf(&dev->dev, GFP_KERNEL, "vmd%d",
992 vmd->instance);
993 if (!vmd->name) {
994 err = -ENOMEM;
995 goto out_release_instance;
996 }
997
998 err = pcim_enable_device(dev);
999 if (err < 0)
1000 goto out_release_instance;
1001
1002 vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
1003 if (!vmd->cfgbar) {
1004 err = -ENOMEM;
1005 goto out_release_instance;
1006 }
1007
1008 pci_set_master(dev);
1009 if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
1010 dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32))) {
1011 err = -ENODEV;
1012 goto out_release_instance;
1013 }
1014
1015 if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
1016 vmd->first_vec = 1;
1017
1018 spin_lock_init(&vmd->cfg_lock);
1019 pci_set_drvdata(dev, vmd);
1020 err = vmd_enable_domain(vmd, features);
1021 if (err)
1022 goto out_release_instance;
1023
1024 dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
1025 vmd->sysdata.domain);
1026 return 0;
1027
1028 out_release_instance:
1029 ida_simple_remove(&vmd_instance_ida, vmd->instance);
1030 return err;
1031 }
1032
vmd_cleanup_srcu(struct vmd_dev * vmd)1033 static void vmd_cleanup_srcu(struct vmd_dev *vmd)
1034 {
1035 int i;
1036
1037 for (i = 0; i < vmd->msix_count; i++)
1038 cleanup_srcu_struct(&vmd->irqs[i].srcu);
1039 }
1040
vmd_remove(struct pci_dev * dev)1041 static void vmd_remove(struct pci_dev *dev)
1042 {
1043 struct vmd_dev *vmd = pci_get_drvdata(dev);
1044
1045 sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
1046 pci_stop_root_bus(vmd->bus);
1047 pci_remove_root_bus(vmd->bus);
1048 vmd_cleanup_srcu(vmd);
1049 vmd_detach_resources(vmd);
1050 vmd_remove_irq_domain(vmd);
1051 ida_simple_remove(&vmd_instance_ida, vmd->instance);
1052 }
1053
vmd_shutdown(struct pci_dev * dev)1054 static void vmd_shutdown(struct pci_dev *dev)
1055 {
1056 struct vmd_dev *vmd = pci_get_drvdata(dev);
1057
1058 vmd_remove_irq_domain(vmd);
1059 }
1060
1061 #ifdef CONFIG_PM_SLEEP
vmd_suspend(struct device * dev)1062 static int vmd_suspend(struct device *dev)
1063 {
1064 struct pci_dev *pdev = to_pci_dev(dev);
1065 struct vmd_dev *vmd = pci_get_drvdata(pdev);
1066 int i;
1067
1068 for (i = 0; i < vmd->msix_count; i++)
1069 devm_free_irq(dev, vmd->irqs[i].virq, &vmd->irqs[i]);
1070
1071 return 0;
1072 }
1073
vmd_resume(struct device * dev)1074 static int vmd_resume(struct device *dev)
1075 {
1076 struct pci_dev *pdev = to_pci_dev(dev);
1077 struct vmd_dev *vmd = pci_get_drvdata(pdev);
1078 int err, i;
1079
1080 if (vmd->irq_domain)
1081 vmd_set_msi_remapping(vmd, true);
1082 else
1083 vmd_set_msi_remapping(vmd, false);
1084
1085 for (i = 0; i < vmd->msix_count; i++) {
1086 err = devm_request_irq(dev, vmd->irqs[i].virq,
1087 vmd_irq, IRQF_NO_THREAD,
1088 vmd->name, &vmd->irqs[i]);
1089 if (err)
1090 return err;
1091 }
1092
1093 return 0;
1094 }
1095 #endif
1096 static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
1097
1098 static const struct pci_device_id vmd_ids[] = {
1099 {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_201D),
1100 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP,},
1101 {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0),
1102 .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW |
1103 VMD_FEAT_HAS_BUS_RESTRICTIONS |
1104 VMD_FEAT_CAN_BYPASS_MSI_REMAP,},
1105 {PCI_VDEVICE(INTEL, 0x467f),
1106 .driver_data = VMD_FEATS_CLIENT,},
1107 {PCI_VDEVICE(INTEL, 0x4c3d),
1108 .driver_data = VMD_FEATS_CLIENT,},
1109 {PCI_VDEVICE(INTEL, 0xa77f),
1110 .driver_data = VMD_FEATS_CLIENT,},
1111 {PCI_VDEVICE(INTEL, 0x7d0b),
1112 .driver_data = VMD_FEATS_CLIENT,},
1113 {PCI_VDEVICE(INTEL, 0xad0b),
1114 .driver_data = VMD_FEATS_CLIENT,},
1115 {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
1116 .driver_data = VMD_FEATS_CLIENT,},
1117 {0,}
1118 };
1119 MODULE_DEVICE_TABLE(pci, vmd_ids);
1120
1121 static struct pci_driver vmd_drv = {
1122 .name = "vmd",
1123 .id_table = vmd_ids,
1124 .probe = vmd_probe,
1125 .remove = vmd_remove,
1126 .shutdown = vmd_shutdown,
1127 .driver = {
1128 .pm = &vmd_dev_pm_ops,
1129 },
1130 };
1131 module_pci_driver(vmd_drv);
1132
1133 MODULE_AUTHOR("Intel Corporation");
1134 MODULE_LICENSE("GPL v2");
1135 MODULE_VERSION("0.6");
1136