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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * PCI Message Signaled Interrupt (MSI)
 
   4 *
   5 * Copyright (C) 2003-2004 Intel
   6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
   7 * Copyright (C) 2016 Christoph Hellwig.
   8 */
   9
  10#include <linux/err.h>
  11#include <linux/mm.h>
  12#include <linux/irq.h>
  13#include <linux/interrupt.h>
  14#include <linux/export.h>
  15#include <linux/ioport.h>
  16#include <linux/pci.h>
  17#include <linux/proc_fs.h>
  18#include <linux/msi.h>
  19#include <linux/smp.h>
  20#include <linux/errno.h>
  21#include <linux/io.h>
  22#include <linux/acpi_iort.h>
  23#include <linux/slab.h>
  24#include <linux/irqdomain.h>
  25#include <linux/of_irq.h>
  26
  27#include "pci.h"
  28
  29static int pci_msi_enable = 1;
  30int pci_msi_ignore_mask;
  31
  32#define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
  33
  34#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
  35static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 
 
 
 
 
 
 
 
  36{
  37	struct irq_domain *domain;
  38
  39	domain = dev_get_msi_domain(&dev->dev);
 
 
 
 
 
 
 
 
 
 
 
  40	if (domain && irq_domain_is_hierarchy(domain))
  41		return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
  42
  43	return arch_setup_msi_irqs(dev, nvec, type);
  44}
  45
  46static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
  47{
  48	struct irq_domain *domain;
  49
  50	domain = dev_get_msi_domain(&dev->dev);
  51	if (domain && irq_domain_is_hierarchy(domain))
  52		msi_domain_free_irqs(domain, &dev->dev);
  53	else
  54		arch_teardown_msi_irqs(dev);
  55}
  56#else
  57#define pci_msi_setup_msi_irqs		arch_setup_msi_irqs
  58#define pci_msi_teardown_msi_irqs	arch_teardown_msi_irqs
  59#endif
  60
  61/* Arch hooks */
  62
  63int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
  64{
  65	struct msi_controller *chip = dev->bus->msi;
  66	int err;
  67
  68	if (!chip || !chip->setup_irq)
  69		return -EINVAL;
  70
  71	err = chip->setup_irq(chip, dev, desc);
  72	if (err < 0)
  73		return err;
  74
  75	irq_set_chip_data(desc->irq, chip);
  76
  77	return 0;
  78}
  79
  80void __weak arch_teardown_msi_irq(unsigned int irq)
  81{
  82	struct msi_controller *chip = irq_get_chip_data(irq);
  83
  84	if (!chip || !chip->teardown_irq)
  85		return;
  86
  87	chip->teardown_irq(chip, irq);
  88}
  89
  90int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  91{
  92	struct msi_controller *chip = dev->bus->msi;
  93	struct msi_desc *entry;
  94	int ret;
  95
  96	if (chip && chip->setup_irqs)
  97		return chip->setup_irqs(chip, dev, nvec, type);
  98	/*
  99	 * If an architecture wants to support multiple MSI, it needs to
 100	 * override arch_setup_msi_irqs()
 101	 */
 102	if (type == PCI_CAP_ID_MSI && nvec > 1)
 103		return 1;
 104
 105	for_each_pci_msi_entry(entry, dev) {
 106		ret = arch_setup_msi_irq(dev, entry);
 107		if (ret < 0)
 108			return ret;
 109		if (ret > 0)
 110			return -ENOSPC;
 111	}
 112
 113	return 0;
 114}
 115
 116/*
 117 * We have a default implementation available as a separate non-weak
 118 * function, as it is used by the Xen x86 PCI code
 119 */
 120void default_teardown_msi_irqs(struct pci_dev *dev)
 121{
 122	int i;
 123	struct msi_desc *entry;
 124
 125	for_each_pci_msi_entry(entry, dev)
 126		if (entry->irq)
 127			for (i = 0; i < entry->nvec_used; i++)
 128				arch_teardown_msi_irq(entry->irq + i);
 129}
 130
 131void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
 132{
 133	return default_teardown_msi_irqs(dev);
 134}
 135
 136static void default_restore_msi_irq(struct pci_dev *dev, int irq)
 137{
 138	struct msi_desc *entry;
 139
 140	entry = NULL;
 141	if (dev->msix_enabled) {
 142		for_each_pci_msi_entry(entry, dev) {
 143			if (irq == entry->irq)
 144				break;
 145		}
 146	} else if (dev->msi_enabled)  {
 147		entry = irq_get_msi_desc(irq);
 148	}
 149
 150	if (entry)
 151		__pci_write_msi_msg(entry, &entry->msg);
 152}
 153
 154void __weak arch_restore_msi_irqs(struct pci_dev *dev)
 155{
 156	return default_restore_msi_irqs(dev);
 157}
 158
 159static inline __attribute_const__ u32 msi_mask(unsigned x)
 160{
 161	/* Don't shift by >= width of type */
 162	if (x >= 5)
 163		return 0xffffffff;
 164	return (1 << (1 << x)) - 1;
 165}
 166
 167/*
 168 * PCI 2.3 does not specify mask bits for each MSI interrupt.  Attempting to
 169 * mask all MSI interrupts by clearing the MSI enable bit does not work
 170 * reliably as devices without an INTx disable bit will then generate a
 171 * level IRQ which will never be cleared.
 172 */
 173u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 174{
 175	u32 mask_bits = desc->masked;
 176
 177	if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit)
 178		return 0;
 179
 180	mask_bits &= ~mask;
 181	mask_bits |= flag;
 182	pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->mask_pos,
 183			       mask_bits);
 184
 185	return mask_bits;
 186}
 187
 188static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 189{
 190	desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag);
 191}
 192
 193static void __iomem *pci_msix_desc_addr(struct msi_desc *desc)
 194{
 195	if (desc->msi_attrib.is_virtual)
 196		return NULL;
 197
 198	return desc->mask_base +
 199		desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 200}
 201
 202/*
 203 * This internal function does not flush PCI writes to the device.
 204 * All users must ensure that they read from the device before either
 205 * assuming that the device state is up to date, or returning out of this
 206 * file.  This saves a few milliseconds when initialising devices with lots
 207 * of MSI-X interrupts.
 208 */
 209u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
 210{
 211	u32 mask_bits = desc->masked;
 212	void __iomem *desc_addr;
 213
 214	if (pci_msi_ignore_mask)
 215		return 0;
 216	desc_addr = pci_msix_desc_addr(desc);
 217	if (!desc_addr)
 218		return 0;
 219
 220	mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
 221	if (flag)
 222		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
 223
 224	writel(mask_bits, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL);
 225
 226	return mask_bits;
 227}
 228
 229static void msix_mask_irq(struct msi_desc *desc, u32 flag)
 230{
 231	desc->masked = __pci_msix_desc_mask_irq(desc, flag);
 232}
 233
 234static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 235{
 236	struct msi_desc *desc = irq_data_get_msi_desc(data);
 237
 238	if (desc->msi_attrib.is_msix) {
 239		msix_mask_irq(desc, flag);
 240		readl(desc->mask_base);		/* Flush write to device */
 241	} else {
 242		unsigned offset = data->irq - desc->irq;
 243		msi_mask_irq(desc, 1 << offset, flag << offset);
 244	}
 245}
 246
 247/**
 248 * pci_msi_mask_irq - Generic IRQ chip callback to mask PCI/MSI interrupts
 249 * @data:	pointer to irqdata associated to that interrupt
 250 */
 251void pci_msi_mask_irq(struct irq_data *data)
 252{
 253	msi_set_mask_bit(data, 1);
 254}
 255EXPORT_SYMBOL_GPL(pci_msi_mask_irq);
 256
 257/**
 258 * pci_msi_unmask_irq - Generic IRQ chip callback to unmask PCI/MSI interrupts
 259 * @data:	pointer to irqdata associated to that interrupt
 260 */
 261void pci_msi_unmask_irq(struct irq_data *data)
 262{
 263	msi_set_mask_bit(data, 0);
 264}
 265EXPORT_SYMBOL_GPL(pci_msi_unmask_irq);
 266
 267void default_restore_msi_irqs(struct pci_dev *dev)
 268{
 269	struct msi_desc *entry;
 270
 271	for_each_pci_msi_entry(entry, dev)
 272		default_restore_msi_irq(dev, entry->irq);
 273}
 274
 275void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 276{
 277	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 278
 279	BUG_ON(dev->current_state != PCI_D0);
 280
 281	if (entry->msi_attrib.is_msix) {
 282		void __iomem *base = pci_msix_desc_addr(entry);
 283
 284		if (!base) {
 285			WARN_ON(1);
 286			return;
 287		}
 288
 289		msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
 290		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
 291		msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
 292	} else {
 293		int pos = dev->msi_cap;
 294		u16 data;
 295
 296		pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
 297				      &msg->address_lo);
 298		if (entry->msi_attrib.is_64) {
 299			pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
 300					      &msg->address_hi);
 301			pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data);
 302		} else {
 303			msg->address_hi = 0;
 304			pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data);
 305		}
 306		msg->data = data;
 307	}
 308}
 309
 310void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 311{
 312	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 313
 314	if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) {
 315		/* Don't touch the hardware now */
 316	} else if (entry->msi_attrib.is_msix) {
 317		void __iomem *base = pci_msix_desc_addr(entry);
 318
 319		if (!base)
 320			goto skip;
 321
 322		writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
 323		writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
 324		writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
 325	} else {
 326		int pos = dev->msi_cap;
 327		u16 msgctl;
 328
 329		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
 330		msgctl &= ~PCI_MSI_FLAGS_QSIZE;
 331		msgctl |= entry->msi_attrib.multiple << 4;
 332		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl);
 333
 334		pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
 335				       msg->address_lo);
 336		if (entry->msi_attrib.is_64) {
 337			pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
 338					       msg->address_hi);
 339			pci_write_config_word(dev, pos + PCI_MSI_DATA_64,
 340					      msg->data);
 341		} else {
 342			pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
 343					      msg->data);
 344		}
 345	}
 346
 347skip:
 348	entry->msg = *msg;
 349
 350	if (entry->write_msi_msg)
 351		entry->write_msi_msg(entry, entry->write_msi_msg_data);
 352
 353}
 354
 355void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
 356{
 357	struct msi_desc *entry = irq_get_msi_desc(irq);
 358
 359	__pci_write_msi_msg(entry, msg);
 360}
 361EXPORT_SYMBOL_GPL(pci_write_msi_msg);
 362
 363static void free_msi_irqs(struct pci_dev *dev)
 364{
 365	struct list_head *msi_list = dev_to_msi_list(&dev->dev);
 366	struct msi_desc *entry, *tmp;
 367	struct attribute **msi_attrs;
 368	struct device_attribute *dev_attr;
 369	int i, count = 0;
 370
 371	for_each_pci_msi_entry(entry, dev)
 372		if (entry->irq)
 373			for (i = 0; i < entry->nvec_used; i++)
 374				BUG_ON(irq_has_action(entry->irq + i));
 375
 376	pci_msi_teardown_msi_irqs(dev);
 377
 378	list_for_each_entry_safe(entry, tmp, msi_list, list) {
 379		if (entry->msi_attrib.is_msix) {
 380			if (list_is_last(&entry->list, msi_list))
 381				iounmap(entry->mask_base);
 382		}
 383
 384		list_del(&entry->list);
 385		free_msi_entry(entry);
 386	}
 387
 388	if (dev->msi_irq_groups) {
 389		sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
 390		msi_attrs = dev->msi_irq_groups[0]->attrs;
 391		while (msi_attrs[count]) {
 392			dev_attr = container_of(msi_attrs[count],
 393						struct device_attribute, attr);
 394			kfree(dev_attr->attr.name);
 395			kfree(dev_attr);
 396			++count;
 397		}
 398		kfree(msi_attrs);
 399		kfree(dev->msi_irq_groups[0]);
 400		kfree(dev->msi_irq_groups);
 401		dev->msi_irq_groups = NULL;
 402	}
 403}
 404
 405static void pci_intx_for_msi(struct pci_dev *dev, int enable)
 406{
 407	if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
 408		pci_intx(dev, enable);
 409}
 410
 411static void __pci_restore_msi_state(struct pci_dev *dev)
 412{
 413	u16 control;
 414	struct msi_desc *entry;
 415
 416	if (!dev->msi_enabled)
 417		return;
 418
 419	entry = irq_get_msi_desc(dev->irq);
 420
 421	pci_intx_for_msi(dev, 0);
 422	pci_msi_set_enable(dev, 0);
 423	arch_restore_msi_irqs(dev);
 424
 425	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 426	msi_mask_irq(entry, msi_mask(entry->msi_attrib.multi_cap),
 427		     entry->masked);
 428	control &= ~PCI_MSI_FLAGS_QSIZE;
 429	control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE;
 430	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
 431}
 432
 433static void __pci_restore_msix_state(struct pci_dev *dev)
 434{
 435	struct msi_desc *entry;
 436
 437	if (!dev->msix_enabled)
 438		return;
 439	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
 440
 441	/* route the table */
 442	pci_intx_for_msi(dev, 0);
 443	pci_msix_clear_and_set_ctrl(dev, 0,
 444				PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL);
 445
 446	arch_restore_msi_irqs(dev);
 447	for_each_pci_msi_entry(entry, dev)
 448		msix_mask_irq(entry, entry->masked);
 449
 450	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 451}
 452
 453void pci_restore_msi_state(struct pci_dev *dev)
 454{
 455	__pci_restore_msi_state(dev);
 456	__pci_restore_msix_state(dev);
 457}
 458EXPORT_SYMBOL_GPL(pci_restore_msi_state);
 459
 460static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
 461			     char *buf)
 462{
 463	struct msi_desc *entry;
 464	unsigned long irq;
 465	int retval;
 466
 467	retval = kstrtoul(attr->attr.name, 10, &irq);
 468	if (retval)
 469		return retval;
 470
 471	entry = irq_get_msi_desc(irq);
 472	if (entry)
 473		return sprintf(buf, "%s\n",
 474				entry->msi_attrib.is_msix ? "msix" : "msi");
 475
 476	return -ENODEV;
 477}
 478
 479static int populate_msi_sysfs(struct pci_dev *pdev)
 480{
 481	struct attribute **msi_attrs;
 482	struct attribute *msi_attr;
 483	struct device_attribute *msi_dev_attr;
 484	struct attribute_group *msi_irq_group;
 485	const struct attribute_group **msi_irq_groups;
 486	struct msi_desc *entry;
 487	int ret = -ENOMEM;
 488	int num_msi = 0;
 489	int count = 0;
 490	int i;
 491
 492	/* Determine how many msi entries we have */
 493	for_each_pci_msi_entry(entry, pdev)
 494		num_msi += entry->nvec_used;
 495	if (!num_msi)
 496		return 0;
 497
 498	/* Dynamically create the MSI attributes for the PCI device */
 499	msi_attrs = kcalloc(num_msi + 1, sizeof(void *), GFP_KERNEL);
 500	if (!msi_attrs)
 501		return -ENOMEM;
 502	for_each_pci_msi_entry(entry, pdev) {
 503		for (i = 0; i < entry->nvec_used; i++) {
 504			msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);
 505			if (!msi_dev_attr)
 506				goto error_attrs;
 507			msi_attrs[count] = &msi_dev_attr->attr;
 508
 509			sysfs_attr_init(&msi_dev_attr->attr);
 510			msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",
 511							    entry->irq + i);
 512			if (!msi_dev_attr->attr.name)
 513				goto error_attrs;
 514			msi_dev_attr->attr.mode = S_IRUGO;
 515			msi_dev_attr->show = msi_mode_show;
 516			++count;
 517		}
 518	}
 519
 520	msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL);
 521	if (!msi_irq_group)
 522		goto error_attrs;
 523	msi_irq_group->name = "msi_irqs";
 524	msi_irq_group->attrs = msi_attrs;
 525
 526	msi_irq_groups = kcalloc(2, sizeof(void *), GFP_KERNEL);
 527	if (!msi_irq_groups)
 528		goto error_irq_group;
 529	msi_irq_groups[0] = msi_irq_group;
 530
 531	ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups);
 532	if (ret)
 533		goto error_irq_groups;
 534	pdev->msi_irq_groups = msi_irq_groups;
 535
 536	return 0;
 537
 538error_irq_groups:
 539	kfree(msi_irq_groups);
 540error_irq_group:
 541	kfree(msi_irq_group);
 542error_attrs:
 543	count = 0;
 544	msi_attr = msi_attrs[count];
 545	while (msi_attr) {
 546		msi_dev_attr = container_of(msi_attr, struct device_attribute, attr);
 547		kfree(msi_attr->name);
 548		kfree(msi_dev_attr);
 549		++count;
 550		msi_attr = msi_attrs[count];
 551	}
 552	kfree(msi_attrs);
 553	return ret;
 554}
 555
 556static struct msi_desc *
 557msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd)
 558{
 559	struct irq_affinity_desc *masks = NULL;
 560	struct msi_desc *entry;
 561	u16 control;
 562
 563	if (affd)
 564		masks = irq_create_affinity_masks(nvec, affd);
 
 
 
 565
 566	/* MSI Entry Initialization */
 567	entry = alloc_msi_entry(&dev->dev, nvec, masks);
 568	if (!entry)
 569		goto out;
 570
 571	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 572
 573	entry->msi_attrib.is_msix	= 0;
 574	entry->msi_attrib.is_64		= !!(control & PCI_MSI_FLAGS_64BIT);
 575	entry->msi_attrib.is_virtual    = 0;
 576	entry->msi_attrib.entry_nr	= 0;
 577	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
 578	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
 579	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
 580	entry->msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));
 581
 582	if (control & PCI_MSI_FLAGS_64BIT)
 583		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
 584	else
 585		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;
 586
 587	/* Save the initial mask status */
 588	if (entry->msi_attrib.maskbit)
 589		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
 590
 591out:
 592	kfree(masks);
 593	return entry;
 594}
 595
 596static int msi_verify_entries(struct pci_dev *dev)
 597{
 598	struct msi_desc *entry;
 599
 600	for_each_pci_msi_entry(entry, dev) {
 601		if (!dev->no_64bit_msi || !entry->msg.address_hi)
 602			continue;
 603		pci_err(dev, "Device has broken 64-bit MSI but arch"
 604			" tried to assign one above 4G\n");
 605		return -EIO;
 606	}
 607	return 0;
 608}
 609
 610/**
 611 * msi_capability_init - configure device's MSI capability structure
 612 * @dev: pointer to the pci_dev data structure of MSI device function
 613 * @nvec: number of interrupts to allocate
 614 * @affd: description of automatic IRQ affinity assignments (may be %NULL)
 615 *
 616 * Setup the MSI capability structure of the device with the requested
 617 * number of interrupts.  A return value of zero indicates the successful
 618 * setup of an entry with the new MSI IRQ.  A negative return value indicates
 619 * an error, and a positive return value indicates the number of interrupts
 620 * which could have been allocated.
 621 */
 622static int msi_capability_init(struct pci_dev *dev, int nvec,
 623			       struct irq_affinity *affd)
 624{
 625	struct msi_desc *entry;
 626	int ret;
 627	unsigned mask;
 628
 629	pci_msi_set_enable(dev, 0);	/* Disable MSI during set up */
 630
 631	entry = msi_setup_entry(dev, nvec, affd);
 632	if (!entry)
 633		return -ENOMEM;
 634
 635	/* All MSIs are unmasked by default; mask them all */
 636	mask = msi_mask(entry->msi_attrib.multi_cap);
 637	msi_mask_irq(entry, mask, mask);
 638
 639	list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
 640
 641	/* Configure MSI capability structure */
 642	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
 643	if (ret) {
 644		msi_mask_irq(entry, mask, ~mask);
 645		free_msi_irqs(dev);
 646		return ret;
 647	}
 648
 649	ret = msi_verify_entries(dev);
 650	if (ret) {
 651		msi_mask_irq(entry, mask, ~mask);
 652		free_msi_irqs(dev);
 653		return ret;
 654	}
 655
 656	ret = populate_msi_sysfs(dev);
 657	if (ret) {
 658		msi_mask_irq(entry, mask, ~mask);
 659		free_msi_irqs(dev);
 660		return ret;
 661	}
 662
 663	/* Set MSI enabled bits	*/
 664	pci_intx_for_msi(dev, 0);
 665	pci_msi_set_enable(dev, 1);
 666	dev->msi_enabled = 1;
 667
 668	pcibios_free_irq(dev);
 669	dev->irq = entry->irq;
 670	return 0;
 671}
 672
 673static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
 674{
 675	resource_size_t phys_addr;
 676	u32 table_offset;
 677	unsigned long flags;
 678	u8 bir;
 679
 680	pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
 681			      &table_offset);
 682	bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
 683	flags = pci_resource_flags(dev, bir);
 684	if (!flags || (flags & IORESOURCE_UNSET))
 685		return NULL;
 686
 687	table_offset &= PCI_MSIX_TABLE_OFFSET;
 688	phys_addr = pci_resource_start(dev, bir) + table_offset;
 689
 690	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
 691}
 692
 693static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
 694			      struct msix_entry *entries, int nvec,
 695			      struct irq_affinity *affd)
 696{
 697	struct irq_affinity_desc *curmsk, *masks = NULL;
 698	struct msi_desc *entry;
 699	int ret, i;
 700	int vec_count = pci_msix_vec_count(dev);
 701
 702	if (affd)
 703		masks = irq_create_affinity_masks(nvec, affd);
 
 
 
 704
 705	for (i = 0, curmsk = masks; i < nvec; i++) {
 706		entry = alloc_msi_entry(&dev->dev, 1, curmsk);
 707		if (!entry) {
 708			if (!i)
 709				iounmap(base);
 710			else
 711				free_msi_irqs(dev);
 712			/* No enough memory. Don't try again */
 713			ret = -ENOMEM;
 714			goto out;
 715		}
 716
 717		entry->msi_attrib.is_msix	= 1;
 718		entry->msi_attrib.is_64		= 1;
 719		if (entries)
 720			entry->msi_attrib.entry_nr = entries[i].entry;
 721		else
 722			entry->msi_attrib.entry_nr = i;
 723
 724		entry->msi_attrib.is_virtual =
 725			entry->msi_attrib.entry_nr >= vec_count;
 726
 727		entry->msi_attrib.default_irq	= dev->irq;
 728		entry->mask_base		= base;
 729
 730		list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
 731		if (masks)
 732			curmsk++;
 733	}
 734	ret = 0;
 735out:
 736	kfree(masks);
 737	return ret;
 738}
 739
 740static void msix_program_entries(struct pci_dev *dev,
 741				 struct msix_entry *entries)
 742{
 743	struct msi_desc *entry;
 744	int i = 0;
 745	void __iomem *desc_addr;
 746
 747	for_each_pci_msi_entry(entry, dev) {
 748		if (entries)
 749			entries[i++].vector = entry->irq;
 750
 751		desc_addr = pci_msix_desc_addr(entry);
 752		if (desc_addr)
 753			entry->masked = readl(desc_addr +
 754					      PCI_MSIX_ENTRY_VECTOR_CTRL);
 755		else
 756			entry->masked = 0;
 757
 758		msix_mask_irq(entry, 1);
 759	}
 760}
 761
 762/**
 763 * msix_capability_init - configure device's MSI-X capability
 764 * @dev: pointer to the pci_dev data structure of MSI-X device function
 765 * @entries: pointer to an array of struct msix_entry entries
 766 * @nvec: number of @entries
 767 * @affd: Optional pointer to enable automatic affinity assignment
 768 *
 769 * Setup the MSI-X capability structure of device function with a
 770 * single MSI-X IRQ. A return of zero indicates the successful setup of
 771 * requested MSI-X entries with allocated IRQs or non-zero for otherwise.
 772 **/
 773static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
 774				int nvec, struct irq_affinity *affd)
 775{
 776	int ret;
 777	u16 control;
 778	void __iomem *base;
 779
 780	/* Ensure MSI-X is disabled while it is set up */
 781	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
 782
 783	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 784	/* Request & Map MSI-X table region */
 785	base = msix_map_region(dev, msix_table_size(control));
 786	if (!base)
 787		return -ENOMEM;
 788
 789	ret = msix_setup_entries(dev, base, entries, nvec, affd);
 790	if (ret)
 791		return ret;
 792
 793	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
 794	if (ret)
 795		goto out_avail;
 796
 797	/* Check if all MSI entries honor device restrictions */
 798	ret = msi_verify_entries(dev);
 799	if (ret)
 800		goto out_free;
 801
 802	/*
 803	 * Some devices require MSI-X to be enabled before we can touch the
 804	 * MSI-X registers.  We need to mask all the vectors to prevent
 805	 * interrupts coming in before they're fully set up.
 806	 */
 807	pci_msix_clear_and_set_ctrl(dev, 0,
 808				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
 809
 810	msix_program_entries(dev, entries);
 811
 812	ret = populate_msi_sysfs(dev);
 813	if (ret)
 814		goto out_free;
 815
 816	/* Set MSI-X enabled bits and unmask the function */
 817	pci_intx_for_msi(dev, 0);
 818	dev->msix_enabled = 1;
 819	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 820
 821	pcibios_free_irq(dev);
 822	return 0;
 823
 824out_avail:
 825	if (ret < 0) {
 826		/*
 827		 * If we had some success, report the number of IRQs
 828		 * we succeeded in setting up.
 829		 */
 830		struct msi_desc *entry;
 831		int avail = 0;
 832
 833		for_each_pci_msi_entry(entry, dev) {
 834			if (entry->irq != 0)
 835				avail++;
 836		}
 837		if (avail != 0)
 838			ret = avail;
 839	}
 840
 841out_free:
 842	free_msi_irqs(dev);
 843
 844	return ret;
 845}
 846
 847/**
 848 * pci_msi_supported - check whether MSI may be enabled on a device
 849 * @dev: pointer to the pci_dev data structure of MSI device function
 850 * @nvec: how many MSIs have been requested?
 851 *
 852 * Look at global flags, the device itself, and its parent buses
 853 * to determine if MSI/-X are supported for the device. If MSI/-X is
 854 * supported return 1, else return 0.
 855 **/
 856static int pci_msi_supported(struct pci_dev *dev, int nvec)
 857{
 858	struct pci_bus *bus;
 859
 860	/* MSI must be globally enabled and supported by the device */
 861	if (!pci_msi_enable)
 862		return 0;
 863
 864	if (!dev || dev->no_msi || dev->current_state != PCI_D0)
 865		return 0;
 866
 867	/*
 868	 * You can't ask to have 0 or less MSIs configured.
 869	 *  a) it's stupid ..
 870	 *  b) the list manipulation code assumes nvec >= 1.
 871	 */
 872	if (nvec < 1)
 873		return 0;
 874
 875	/*
 876	 * Any bridge which does NOT route MSI transactions from its
 877	 * secondary bus to its primary bus must set NO_MSI flag on
 878	 * the secondary pci_bus.
 879	 * We expect only arch-specific PCI host bus controller driver
 880	 * or quirks for specific PCI bridges to be setting NO_MSI.
 881	 */
 882	for (bus = dev->bus; bus; bus = bus->parent)
 883		if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
 884			return 0;
 885
 886	return 1;
 887}
 888
 889/**
 890 * pci_msi_vec_count - Return the number of MSI vectors a device can send
 891 * @dev: device to report about
 892 *
 893 * This function returns the number of MSI vectors a device requested via
 894 * Multiple Message Capable register. It returns a negative errno if the
 895 * device is not capable sending MSI interrupts. Otherwise, the call succeeds
 896 * and returns a power of two, up to a maximum of 2^5 (32), according to the
 897 * MSI specification.
 898 **/
 899int pci_msi_vec_count(struct pci_dev *dev)
 900{
 901	int ret;
 902	u16 msgctl;
 903
 904	if (!dev->msi_cap)
 905		return -EINVAL;
 906
 907	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl);
 908	ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);
 909
 910	return ret;
 911}
 912EXPORT_SYMBOL(pci_msi_vec_count);
 913
 914static void pci_msi_shutdown(struct pci_dev *dev)
 915{
 916	struct msi_desc *desc;
 917	u32 mask;
 918
 919	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 920		return;
 921
 922	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
 923	desc = first_pci_msi_entry(dev);
 924
 925	pci_msi_set_enable(dev, 0);
 926	pci_intx_for_msi(dev, 1);
 927	dev->msi_enabled = 0;
 928
 929	/* Return the device with MSI unmasked as initial states */
 930	mask = msi_mask(desc->msi_attrib.multi_cap);
 931	/* Keep cached state to be restored */
 932	__pci_msi_desc_mask_irq(desc, mask, ~mask);
 933
 934	/* Restore dev->irq to its default pin-assertion IRQ */
 935	dev->irq = desc->msi_attrib.default_irq;
 936	pcibios_alloc_irq(dev);
 937}
 938
 939void pci_disable_msi(struct pci_dev *dev)
 940{
 941	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 942		return;
 943
 944	pci_msi_shutdown(dev);
 945	free_msi_irqs(dev);
 946}
 947EXPORT_SYMBOL(pci_disable_msi);
 948
 949/**
 950 * pci_msix_vec_count - return the number of device's MSI-X table entries
 951 * @dev: pointer to the pci_dev data structure of MSI-X device function
 952 * This function returns the number of device's MSI-X table entries and
 953 * therefore the number of MSI-X vectors device is capable of sending.
 954 * It returns a negative errno if the device is not capable of sending MSI-X
 955 * interrupts.
 956 **/
 957int pci_msix_vec_count(struct pci_dev *dev)
 958{
 959	u16 control;
 960
 961	if (!dev->msix_cap)
 962		return -EINVAL;
 963
 964	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 965	return msix_table_size(control);
 966}
 967EXPORT_SYMBOL(pci_msix_vec_count);
 968
 969static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
 970			     int nvec, struct irq_affinity *affd, int flags)
 971{
 972	int nr_entries;
 973	int i, j;
 974
 975	if (!pci_msi_supported(dev, nvec))
 976		return -EINVAL;
 977
 978	nr_entries = pci_msix_vec_count(dev);
 979	if (nr_entries < 0)
 980		return nr_entries;
 981	if (nvec > nr_entries && !(flags & PCI_IRQ_VIRTUAL))
 982		return nr_entries;
 983
 984	if (entries) {
 985		/* Check for any invalid entries */
 986		for (i = 0; i < nvec; i++) {
 987			if (entries[i].entry >= nr_entries)
 988				return -EINVAL;		/* invalid entry */
 989			for (j = i + 1; j < nvec; j++) {
 990				if (entries[i].entry == entries[j].entry)
 991					return -EINVAL;	/* duplicate entry */
 992			}
 993		}
 994	}
 
 995
 996	/* Check whether driver already requested for MSI IRQ */
 997	if (dev->msi_enabled) {
 998		pci_info(dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
 999		return -EINVAL;
1000	}
1001	return msix_capability_init(dev, entries, nvec, affd);
1002}
1003
1004static void pci_msix_shutdown(struct pci_dev *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1005{
1006	struct msi_desc *entry;
1007
1008	if (!pci_msi_enable || !dev || !dev->msix_enabled)
1009		return;
1010
1011	if (pci_dev_is_disconnected(dev)) {
1012		dev->msix_enabled = 0;
1013		return;
1014	}
1015
1016	/* Return the device with MSI-X masked as initial states */
1017	for_each_pci_msi_entry(entry, dev) {
1018		/* Keep cached states to be restored */
1019		__pci_msix_desc_mask_irq(entry, 1);
1020	}
1021
1022	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1023	pci_intx_for_msi(dev, 1);
1024	dev->msix_enabled = 0;
1025	pcibios_alloc_irq(dev);
1026}
1027
1028void pci_disable_msix(struct pci_dev *dev)
1029{
1030	if (!pci_msi_enable || !dev || !dev->msix_enabled)
1031		return;
1032
1033	pci_msix_shutdown(dev);
1034	free_msi_irqs(dev);
1035}
1036EXPORT_SYMBOL(pci_disable_msix);
1037
1038void pci_no_msi(void)
1039{
1040	pci_msi_enable = 0;
1041}
1042
1043/**
1044 * pci_msi_enabled - is MSI enabled?
1045 *
1046 * Returns true if MSI has not been disabled by the command-line option
1047 * pci=nomsi.
1048 **/
1049int pci_msi_enabled(void)
1050{
1051	return pci_msi_enable;
1052}
1053EXPORT_SYMBOL(pci_msi_enabled);
1054
1055static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
1056				  struct irq_affinity *affd)
1057{
1058	int nvec;
1059	int rc;
1060
1061	if (!pci_msi_supported(dev, minvec))
1062		return -EINVAL;
1063
1064	/* Check whether driver already requested MSI-X IRQs */
 
 
1065	if (dev->msix_enabled) {
1066		pci_info(dev, "can't enable MSI (MSI-X already enabled)\n");
 
1067		return -EINVAL;
1068	}
1069
1070	if (maxvec < minvec)
1071		return -ERANGE;
1072
1073	if (WARN_ON_ONCE(dev->msi_enabled))
1074		return -EINVAL;
1075
1076	nvec = pci_msi_vec_count(dev);
1077	if (nvec < 0)
1078		return nvec;
1079	if (nvec < minvec)
1080		return -ENOSPC;
1081
1082	if (nvec > maxvec)
1083		nvec = maxvec;
1084
1085	for (;;) {
1086		if (affd) {
1087			nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
1088			if (nvec < minvec)
1089				return -ENOSPC;
1090		}
1091
1092		rc = msi_capability_init(dev, nvec, affd);
1093		if (rc == 0)
1094			return nvec;
1095
1096		if (rc < 0)
1097			return rc;
1098		if (rc < minvec)
1099			return -ENOSPC;
1100
1101		nvec = rc;
1102	}
1103}
1104
1105/* deprecated, don't use */
1106int pci_enable_msi(struct pci_dev *dev)
 
 
 
 
 
 
 
 
 
 
 
1107{
1108	int rc = __pci_enable_msi_range(dev, 1, 1, NULL);
1109	if (rc < 0)
1110		return rc;
1111	return 0;
1112}
1113EXPORT_SYMBOL(pci_enable_msi);
1114
1115static int __pci_enable_msix_range(struct pci_dev *dev,
1116				   struct msix_entry *entries, int minvec,
1117				   int maxvec, struct irq_affinity *affd,
1118				   int flags)
1119{
1120	int rc, nvec = maxvec;
1121
1122	if (maxvec < minvec)
1123		return -ERANGE;
1124
1125	if (WARN_ON_ONCE(dev->msix_enabled))
1126		return -EINVAL;
1127
1128	for (;;) {
1129		if (affd) {
1130			nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
1131			if (nvec < minvec)
1132				return -ENOSPC;
1133		}
1134
1135		rc = __pci_enable_msix(dev, entries, nvec, affd, flags);
1136		if (rc == 0)
1137			return nvec;
1138
1139		if (rc < 0)
1140			return rc;
1141		if (rc < minvec)
1142			return -ENOSPC;
1143
1144		nvec = rc;
1145	}
1146}
1147
1148/**
1149 * pci_enable_msix_range - configure device's MSI-X capability structure
1150 * @dev: pointer to the pci_dev data structure of MSI-X device function
1151 * @entries: pointer to an array of MSI-X entries
1152 * @minvec: minimum number of MSI-X IRQs requested
1153 * @maxvec: maximum number of MSI-X IRQs requested
1154 *
1155 * Setup the MSI-X capability structure of device function with a maximum
1156 * possible number of interrupts in the range between @minvec and @maxvec
1157 * upon its software driver call to request for MSI-X mode enabled on its
1158 * hardware device function. It returns a negative errno if an error occurs.
1159 * If it succeeds, it returns the actual number of interrupts allocated and
1160 * indicates the successful configuration of MSI-X capability structure
1161 * with new allocated MSI-X interrupts.
1162 **/
1163int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
1164		int minvec, int maxvec)
1165{
1166	return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL, 0);
1167}
1168EXPORT_SYMBOL(pci_enable_msix_range);
1169
1170/**
1171 * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
1172 * @dev:		PCI device to operate on
1173 * @min_vecs:		minimum number of vectors required (must be >= 1)
1174 * @max_vecs:		maximum (desired) number of vectors
1175 * @flags:		flags or quirks for the allocation
1176 * @affd:		optional description of the affinity requirements
1177 *
1178 * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
1179 * vectors if available, and fall back to a single legacy vector
1180 * if neither is available.  Return the number of vectors allocated,
1181 * (which might be smaller than @max_vecs) if successful, or a negative
1182 * error code on error. If less than @min_vecs interrupt vectors are
1183 * available for @dev the function will fail with -ENOSPC.
1184 *
1185 * To get the Linux IRQ number used for a vector that can be passed to
1186 * request_irq() use the pci_irq_vector() helper.
1187 */
1188int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
1189				   unsigned int max_vecs, unsigned int flags,
1190				   struct irq_affinity *affd)
1191{
1192	struct irq_affinity msi_default_affd = {0};
1193	int msix_vecs = -ENOSPC;
1194	int msi_vecs = -ENOSPC;
1195
1196	if (flags & PCI_IRQ_AFFINITY) {
1197		if (!affd)
1198			affd = &msi_default_affd;
 
 
 
 
 
 
 
 
 
 
1199	} else {
1200		if (WARN_ON(affd))
1201			affd = NULL;
1202	}
1203
1204	if (flags & PCI_IRQ_MSIX) {
1205		msix_vecs = __pci_enable_msix_range(dev, NULL, min_vecs,
1206						    max_vecs, affd, flags);
1207		if (msix_vecs > 0)
1208			return msix_vecs;
1209	}
1210
1211	if (flags & PCI_IRQ_MSI) {
1212		msi_vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs,
1213						  affd);
1214		if (msi_vecs > 0)
1215			return msi_vecs;
1216	}
1217
1218	/* use legacy IRQ if allowed */
1219	if (flags & PCI_IRQ_LEGACY) {
1220		if (min_vecs == 1 && dev->irq) {
1221			/*
1222			 * Invoke the affinity spreading logic to ensure that
1223			 * the device driver can adjust queue configuration
1224			 * for the single interrupt case.
1225			 */
1226			if (affd)
1227				irq_create_affinity_masks(1, affd);
1228			pci_intx(dev, 1);
1229			return 1;
1230		}
1231	}
1232
1233	if (msix_vecs == -ENOSPC)
1234		return -ENOSPC;
1235	return msi_vecs;
1236}
1237EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
1238
1239/**
1240 * pci_free_irq_vectors - free previously allocated IRQs for a device
1241 * @dev:		PCI device to operate on
1242 *
1243 * Undoes the allocations and enabling in pci_alloc_irq_vectors().
1244 */
1245void pci_free_irq_vectors(struct pci_dev *dev)
1246{
1247	pci_disable_msix(dev);
1248	pci_disable_msi(dev);
1249}
1250EXPORT_SYMBOL(pci_free_irq_vectors);
1251
1252/**
1253 * pci_irq_vector - return Linux IRQ number of a device vector
1254 * @dev: PCI device to operate on
1255 * @nr: device-relative interrupt vector index (0-based).
1256 */
1257int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
1258{
1259	if (dev->msix_enabled) {
1260		struct msi_desc *entry;
1261		int i = 0;
1262
1263		for_each_pci_msi_entry(entry, dev) {
1264			if (i == nr)
1265				return entry->irq;
1266			i++;
1267		}
1268		WARN_ON_ONCE(1);
1269		return -EINVAL;
1270	}
1271
1272	if (dev->msi_enabled) {
1273		struct msi_desc *entry = first_pci_msi_entry(dev);
1274
1275		if (WARN_ON_ONCE(nr >= entry->nvec_used))
1276			return -EINVAL;
1277	} else {
1278		if (WARN_ON_ONCE(nr > 0))
1279			return -EINVAL;
1280	}
1281
1282	return dev->irq + nr;
1283}
1284EXPORT_SYMBOL(pci_irq_vector);
1285
1286/**
1287 * pci_irq_get_affinity - return the affinity of a particular MSI vector
1288 * @dev:	PCI device to operate on
1289 * @nr:		device-relative interrupt vector index (0-based).
1290 */
1291const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
1292{
1293	if (dev->msix_enabled) {
1294		struct msi_desc *entry;
1295		int i = 0;
1296
1297		for_each_pci_msi_entry(entry, dev) {
1298			if (i == nr)
1299				return &entry->affinity->mask;
1300			i++;
1301		}
1302		WARN_ON_ONCE(1);
1303		return NULL;
1304	} else if (dev->msi_enabled) {
1305		struct msi_desc *entry = first_pci_msi_entry(dev);
1306
1307		if (WARN_ON_ONCE(!entry || !entry->affinity ||
1308				 nr >= entry->nvec_used))
1309			return NULL;
1310
1311		return &entry->affinity[nr].mask;
1312	} else {
1313		return cpu_possible_mask;
1314	}
1315}
1316EXPORT_SYMBOL(pci_irq_get_affinity);
1317
1318/**
1319 * pci_irq_get_node - return the NUMA node of a particular MSI vector
1320 * @pdev:	PCI device to operate on
1321 * @vec:	device-relative interrupt vector index (0-based).
1322 */
1323int pci_irq_get_node(struct pci_dev *pdev, int vec)
1324{
1325	const struct cpumask *mask;
1326
1327	mask = pci_irq_get_affinity(pdev, vec);
1328	if (mask)
1329		return local_memory_node(cpu_to_node(cpumask_first(mask)));
1330	return dev_to_node(&pdev->dev);
1331}
1332EXPORT_SYMBOL(pci_irq_get_node);
1333
1334struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc)
1335{
1336	return to_pci_dev(desc->dev);
1337}
1338EXPORT_SYMBOL(msi_desc_to_pci_dev);
1339
1340void *msi_desc_to_pci_sysdata(struct msi_desc *desc)
1341{
1342	struct pci_dev *dev = msi_desc_to_pci_dev(desc);
1343
1344	return dev->bus->sysdata;
1345}
1346EXPORT_SYMBOL_GPL(msi_desc_to_pci_sysdata);
1347
1348#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
1349/**
1350 * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
1351 * @irq_data:	Pointer to interrupt data of the MSI interrupt
1352 * @msg:	Pointer to the message
1353 */
1354void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
1355{
1356	struct msi_desc *desc = irq_data_get_msi_desc(irq_data);
1357
1358	/*
1359	 * For MSI-X desc->irq is always equal to irq_data->irq. For
1360	 * MSI only the first interrupt of MULTI MSI passes the test.
1361	 */
1362	if (desc->irq == irq_data->irq)
1363		__pci_write_msi_msg(desc, msg);
1364}
1365
1366/**
1367 * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
1368 * @dev:	Pointer to the PCI device
1369 * @desc:	Pointer to the MSI descriptor
1370 *
1371 * The ID number is only used within the irqdomain.
1372 */
1373irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
1374					  struct msi_desc *desc)
1375{
1376	return (irq_hw_number_t)desc->msi_attrib.entry_nr |
1377		pci_dev_id(dev) << 11 |
1378		(pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27;
1379}
1380
1381static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
1382{
1383	return !desc->msi_attrib.is_msix && desc->nvec_used > 1;
1384}
1385
1386/**
1387 * pci_msi_domain_check_cap - Verify that @domain supports the capabilities
1388 * 			      for @dev
1389 * @domain:	The interrupt domain to check
1390 * @info:	The domain info for verification
1391 * @dev:	The device to check
1392 *
1393 * Returns:
1394 *  0 if the functionality is supported
1395 *  1 if Multi MSI is requested, but the domain does not support it
1396 *  -ENOTSUPP otherwise
1397 */
1398int pci_msi_domain_check_cap(struct irq_domain *domain,
1399			     struct msi_domain_info *info, struct device *dev)
1400{
1401	struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));
1402
1403	/* Special handling to support __pci_enable_msi_range() */
1404	if (pci_msi_desc_is_multi_msi(desc) &&
1405	    !(info->flags & MSI_FLAG_MULTI_PCI_MSI))
1406		return 1;
1407	else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX))
1408		return -ENOTSUPP;
1409
1410	return 0;
1411}
1412
1413static int pci_msi_domain_handle_error(struct irq_domain *domain,
1414				       struct msi_desc *desc, int error)
1415{
1416	/* Special handling to support __pci_enable_msi_range() */
1417	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
1418		return 1;
1419
1420	return error;
1421}
1422
1423#ifdef GENERIC_MSI_DOMAIN_OPS
1424static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
1425				    struct msi_desc *desc)
1426{
1427	arg->desc = desc;
1428	arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc),
1429					       desc);
1430}
1431#else
1432#define pci_msi_domain_set_desc		NULL
1433#endif
1434
1435static struct msi_domain_ops pci_msi_domain_ops_default = {
1436	.set_desc	= pci_msi_domain_set_desc,
1437	.msi_check	= pci_msi_domain_check_cap,
1438	.handle_error	= pci_msi_domain_handle_error,
1439};
1440
1441static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
1442{
1443	struct msi_domain_ops *ops = info->ops;
1444
1445	if (ops == NULL) {
1446		info->ops = &pci_msi_domain_ops_default;
1447	} else {
1448		if (ops->set_desc == NULL)
1449			ops->set_desc = pci_msi_domain_set_desc;
1450		if (ops->msi_check == NULL)
1451			ops->msi_check = pci_msi_domain_check_cap;
1452		if (ops->handle_error == NULL)
1453			ops->handle_error = pci_msi_domain_handle_error;
1454	}
1455}
1456
1457static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
1458{
1459	struct irq_chip *chip = info->chip;
1460
1461	BUG_ON(!chip);
1462	if (!chip->irq_write_msi_msg)
1463		chip->irq_write_msi_msg = pci_msi_domain_write_msg;
1464	if (!chip->irq_mask)
1465		chip->irq_mask = pci_msi_mask_irq;
1466	if (!chip->irq_unmask)
1467		chip->irq_unmask = pci_msi_unmask_irq;
1468}
1469
1470/**
1471 * pci_msi_create_irq_domain - Create a MSI interrupt domain
1472 * @fwnode:	Optional fwnode of the interrupt controller
1473 * @info:	MSI domain info
1474 * @parent:	Parent irq domain
1475 *
1476 * Updates the domain and chip ops and creates a MSI interrupt domain.
1477 *
1478 * Returns:
1479 * A domain pointer or NULL in case of failure.
1480 */
1481struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
1482					     struct msi_domain_info *info,
1483					     struct irq_domain *parent)
1484{
1485	struct irq_domain *domain;
1486
1487	if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE))
1488		info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
1489
1490	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
1491		pci_msi_domain_update_dom_ops(info);
1492	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
1493		pci_msi_domain_update_chip_ops(info);
1494
1495	info->flags |= MSI_FLAG_ACTIVATE_EARLY;
1496	if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
1497		info->flags |= MSI_FLAG_MUST_REACTIVATE;
1498
1499	/* PCI-MSI is oneshot-safe */
1500	info->chip->flags |= IRQCHIP_ONESHOT_SAFE;
1501
1502	domain = msi_create_irq_domain(fwnode, info, parent);
1503	if (!domain)
1504		return NULL;
1505
1506	irq_domain_update_bus_token(domain, DOMAIN_BUS_PCI_MSI);
1507	return domain;
1508}
1509EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain);
1510
1511/*
1512 * Users of the generic MSI infrastructure expect a device to have a single ID,
1513 * so with DMA aliases we have to pick the least-worst compromise. Devices with
1514 * DMA phantom functions tend to still emit MSIs from the real function number,
1515 * so we ignore those and only consider topological aliases where either the
1516 * alias device or RID appears on a different bus number. We also make the
1517 * reasonable assumption that bridges are walked in an upstream direction (so
1518 * the last one seen wins), and the much braver assumption that the most likely
1519 * case is that of PCI->PCIe so we should always use the alias RID. This echoes
1520 * the logic from intel_irq_remapping's set_msi_sid(), which presumably works
1521 * well enough in practice; in the face of the horrible PCIe<->PCI-X conditions
1522 * for taking ownership all we can really do is close our eyes and hope...
 
 
 
 
 
 
 
 
1523 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1524static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
1525{
1526	u32 *pa = data;
1527	u8 bus = PCI_BUS_NUM(*pa);
1528
1529	if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus)
1530		*pa = alias;
1531
 
1532	return 0;
1533}
1534
1535/**
1536 * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
1537 * @domain:	The interrupt domain
1538 * @pdev:	The PCI device.
1539 *
1540 * The RID for a device is formed from the alias, with a firmware
1541 * supplied mapping applied
1542 *
1543 * Returns: The RID.
1544 */
1545u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
1546{
1547	struct device_node *of_node;
1548	u32 rid = pci_dev_id(pdev);
1549
1550	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
1551
1552	of_node = irq_domain_get_of_node(domain);
1553	rid = of_node ? of_msi_map_rid(&pdev->dev, of_node, rid) :
1554			iort_msi_map_rid(&pdev->dev, rid);
1555
1556	return rid;
1557}
1558
1559/**
1560 * pci_msi_get_device_domain - Get the MSI domain for a given PCI device
1561 * @pdev:	The PCI device
1562 *
1563 * Use the firmware data to find a device-specific MSI domain
1564 * (i.e. not one that is set as a default).
1565 *
1566 * Returns: The corresponding MSI domain or NULL if none has been found.
1567 */
1568struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
1569{
1570	struct irq_domain *dom;
1571	u32 rid = pci_dev_id(pdev);
1572
1573	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
1574	dom = of_msi_map_get_device_domain(&pdev->dev, rid);
1575	if (!dom)
1576		dom = iort_get_device_domain(&pdev->dev, rid);
1577	return dom;
1578}
1579#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
v4.10.11
 
   1/*
   2 * File:	msi.c
   3 * Purpose:	PCI Message Signaled Interrupt (MSI)
   4 *
   5 * Copyright (C) 2003-2004 Intel
   6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
   7 * Copyright (C) 2016 Christoph Hellwig.
   8 */
   9
  10#include <linux/err.h>
  11#include <linux/mm.h>
  12#include <linux/irq.h>
  13#include <linux/interrupt.h>
  14#include <linux/export.h>
  15#include <linux/ioport.h>
  16#include <linux/pci.h>
  17#include <linux/proc_fs.h>
  18#include <linux/msi.h>
  19#include <linux/smp.h>
  20#include <linux/errno.h>
  21#include <linux/io.h>
  22#include <linux/acpi_iort.h>
  23#include <linux/slab.h>
  24#include <linux/irqdomain.h>
  25#include <linux/of_irq.h>
  26
  27#include "pci.h"
  28
  29static int pci_msi_enable = 1;
  30int pci_msi_ignore_mask;
  31
  32#define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
  33
  34#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
  35static struct irq_domain *pci_msi_default_domain;
  36static DEFINE_MUTEX(pci_msi_domain_lock);
  37
  38struct irq_domain * __weak arch_get_pci_msi_domain(struct pci_dev *dev)
  39{
  40	return pci_msi_default_domain;
  41}
  42
  43static struct irq_domain *pci_msi_get_domain(struct pci_dev *dev)
  44{
  45	struct irq_domain *domain;
  46
  47	domain = dev_get_msi_domain(&dev->dev);
  48	if (domain)
  49		return domain;
  50
  51	return arch_get_pci_msi_domain(dev);
  52}
  53
  54static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
  55{
  56	struct irq_domain *domain;
  57
  58	domain = pci_msi_get_domain(dev);
  59	if (domain && irq_domain_is_hierarchy(domain))
  60		return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
  61
  62	return arch_setup_msi_irqs(dev, nvec, type);
  63}
  64
  65static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
  66{
  67	struct irq_domain *domain;
  68
  69	domain = pci_msi_get_domain(dev);
  70	if (domain && irq_domain_is_hierarchy(domain))
  71		pci_msi_domain_free_irqs(domain, dev);
  72	else
  73		arch_teardown_msi_irqs(dev);
  74}
  75#else
  76#define pci_msi_setup_msi_irqs		arch_setup_msi_irqs
  77#define pci_msi_teardown_msi_irqs	arch_teardown_msi_irqs
  78#endif
  79
  80/* Arch hooks */
  81
  82int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
  83{
  84	struct msi_controller *chip = dev->bus->msi;
  85	int err;
  86
  87	if (!chip || !chip->setup_irq)
  88		return -EINVAL;
  89
  90	err = chip->setup_irq(chip, dev, desc);
  91	if (err < 0)
  92		return err;
  93
  94	irq_set_chip_data(desc->irq, chip);
  95
  96	return 0;
  97}
  98
  99void __weak arch_teardown_msi_irq(unsigned int irq)
 100{
 101	struct msi_controller *chip = irq_get_chip_data(irq);
 102
 103	if (!chip || !chip->teardown_irq)
 104		return;
 105
 106	chip->teardown_irq(chip, irq);
 107}
 108
 109int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 110{
 111	struct msi_controller *chip = dev->bus->msi;
 112	struct msi_desc *entry;
 113	int ret;
 114
 115	if (chip && chip->setup_irqs)
 116		return chip->setup_irqs(chip, dev, nvec, type);
 117	/*
 118	 * If an architecture wants to support multiple MSI, it needs to
 119	 * override arch_setup_msi_irqs()
 120	 */
 121	if (type == PCI_CAP_ID_MSI && nvec > 1)
 122		return 1;
 123
 124	for_each_pci_msi_entry(entry, dev) {
 125		ret = arch_setup_msi_irq(dev, entry);
 126		if (ret < 0)
 127			return ret;
 128		if (ret > 0)
 129			return -ENOSPC;
 130	}
 131
 132	return 0;
 133}
 134
 135/*
 136 * We have a default implementation available as a separate non-weak
 137 * function, as it is used by the Xen x86 PCI code
 138 */
 139void default_teardown_msi_irqs(struct pci_dev *dev)
 140{
 141	int i;
 142	struct msi_desc *entry;
 143
 144	for_each_pci_msi_entry(entry, dev)
 145		if (entry->irq)
 146			for (i = 0; i < entry->nvec_used; i++)
 147				arch_teardown_msi_irq(entry->irq + i);
 148}
 149
 150void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
 151{
 152	return default_teardown_msi_irqs(dev);
 153}
 154
 155static void default_restore_msi_irq(struct pci_dev *dev, int irq)
 156{
 157	struct msi_desc *entry;
 158
 159	entry = NULL;
 160	if (dev->msix_enabled) {
 161		for_each_pci_msi_entry(entry, dev) {
 162			if (irq == entry->irq)
 163				break;
 164		}
 165	} else if (dev->msi_enabled)  {
 166		entry = irq_get_msi_desc(irq);
 167	}
 168
 169	if (entry)
 170		__pci_write_msi_msg(entry, &entry->msg);
 171}
 172
 173void __weak arch_restore_msi_irqs(struct pci_dev *dev)
 174{
 175	return default_restore_msi_irqs(dev);
 176}
 177
 178static inline __attribute_const__ u32 msi_mask(unsigned x)
 179{
 180	/* Don't shift by >= width of type */
 181	if (x >= 5)
 182		return 0xffffffff;
 183	return (1 << (1 << x)) - 1;
 184}
 185
 186/*
 187 * PCI 2.3 does not specify mask bits for each MSI interrupt.  Attempting to
 188 * mask all MSI interrupts by clearing the MSI enable bit does not work
 189 * reliably as devices without an INTx disable bit will then generate a
 190 * level IRQ which will never be cleared.
 191 */
 192u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 193{
 194	u32 mask_bits = desc->masked;
 195
 196	if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit)
 197		return 0;
 198
 199	mask_bits &= ~mask;
 200	mask_bits |= flag;
 201	pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->mask_pos,
 202			       mask_bits);
 203
 204	return mask_bits;
 205}
 206
 207static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 208{
 209	desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag);
 210}
 211
 212static void __iomem *pci_msix_desc_addr(struct msi_desc *desc)
 213{
 
 
 
 214	return desc->mask_base +
 215		desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
 216}
 217
 218/*
 219 * This internal function does not flush PCI writes to the device.
 220 * All users must ensure that they read from the device before either
 221 * assuming that the device state is up to date, or returning out of this
 222 * file.  This saves a few milliseconds when initialising devices with lots
 223 * of MSI-X interrupts.
 224 */
 225u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
 226{
 227	u32 mask_bits = desc->masked;
 
 228
 229	if (pci_msi_ignore_mask)
 230		return 0;
 
 
 
 231
 232	mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
 233	if (flag)
 234		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
 235	writel(mask_bits, pci_msix_desc_addr(desc) + PCI_MSIX_ENTRY_VECTOR_CTRL);
 
 236
 237	return mask_bits;
 238}
 239
 240static void msix_mask_irq(struct msi_desc *desc, u32 flag)
 241{
 242	desc->masked = __pci_msix_desc_mask_irq(desc, flag);
 243}
 244
 245static void msi_set_mask_bit(struct irq_data *data, u32 flag)
 246{
 247	struct msi_desc *desc = irq_data_get_msi_desc(data);
 248
 249	if (desc->msi_attrib.is_msix) {
 250		msix_mask_irq(desc, flag);
 251		readl(desc->mask_base);		/* Flush write to device */
 252	} else {
 253		unsigned offset = data->irq - desc->irq;
 254		msi_mask_irq(desc, 1 << offset, flag << offset);
 255	}
 256}
 257
 258/**
 259 * pci_msi_mask_irq - Generic irq chip callback to mask PCI/MSI interrupts
 260 * @data:	pointer to irqdata associated to that interrupt
 261 */
 262void pci_msi_mask_irq(struct irq_data *data)
 263{
 264	msi_set_mask_bit(data, 1);
 265}
 266EXPORT_SYMBOL_GPL(pci_msi_mask_irq);
 267
 268/**
 269 * pci_msi_unmask_irq - Generic irq chip callback to unmask PCI/MSI interrupts
 270 * @data:	pointer to irqdata associated to that interrupt
 271 */
 272void pci_msi_unmask_irq(struct irq_data *data)
 273{
 274	msi_set_mask_bit(data, 0);
 275}
 276EXPORT_SYMBOL_GPL(pci_msi_unmask_irq);
 277
 278void default_restore_msi_irqs(struct pci_dev *dev)
 279{
 280	struct msi_desc *entry;
 281
 282	for_each_pci_msi_entry(entry, dev)
 283		default_restore_msi_irq(dev, entry->irq);
 284}
 285
 286void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 287{
 288	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 289
 290	BUG_ON(dev->current_state != PCI_D0);
 291
 292	if (entry->msi_attrib.is_msix) {
 293		void __iomem *base = pci_msix_desc_addr(entry);
 294
 
 
 
 
 
 295		msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
 296		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
 297		msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
 298	} else {
 299		int pos = dev->msi_cap;
 300		u16 data;
 301
 302		pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
 303				      &msg->address_lo);
 304		if (entry->msi_attrib.is_64) {
 305			pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
 306					      &msg->address_hi);
 307			pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data);
 308		} else {
 309			msg->address_hi = 0;
 310			pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data);
 311		}
 312		msg->data = data;
 313	}
 314}
 315
 316void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 317{
 318	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 319
 320	if (dev->current_state != PCI_D0) {
 321		/* Don't touch the hardware now */
 322	} else if (entry->msi_attrib.is_msix) {
 323		void __iomem *base = pci_msix_desc_addr(entry);
 324
 
 
 
 325		writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
 326		writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
 327		writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
 328	} else {
 329		int pos = dev->msi_cap;
 330		u16 msgctl;
 331
 332		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
 333		msgctl &= ~PCI_MSI_FLAGS_QSIZE;
 334		msgctl |= entry->msi_attrib.multiple << 4;
 335		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl);
 336
 337		pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
 338				       msg->address_lo);
 339		if (entry->msi_attrib.is_64) {
 340			pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
 341					       msg->address_hi);
 342			pci_write_config_word(dev, pos + PCI_MSI_DATA_64,
 343					      msg->data);
 344		} else {
 345			pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
 346					      msg->data);
 347		}
 348	}
 
 
 349	entry->msg = *msg;
 
 
 
 
 350}
 351
 352void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
 353{
 354	struct msi_desc *entry = irq_get_msi_desc(irq);
 355
 356	__pci_write_msi_msg(entry, msg);
 357}
 358EXPORT_SYMBOL_GPL(pci_write_msi_msg);
 359
 360static void free_msi_irqs(struct pci_dev *dev)
 361{
 362	struct list_head *msi_list = dev_to_msi_list(&dev->dev);
 363	struct msi_desc *entry, *tmp;
 364	struct attribute **msi_attrs;
 365	struct device_attribute *dev_attr;
 366	int i, count = 0;
 367
 368	for_each_pci_msi_entry(entry, dev)
 369		if (entry->irq)
 370			for (i = 0; i < entry->nvec_used; i++)
 371				BUG_ON(irq_has_action(entry->irq + i));
 372
 373	pci_msi_teardown_msi_irqs(dev);
 374
 375	list_for_each_entry_safe(entry, tmp, msi_list, list) {
 376		if (entry->msi_attrib.is_msix) {
 377			if (list_is_last(&entry->list, msi_list))
 378				iounmap(entry->mask_base);
 379		}
 380
 381		list_del(&entry->list);
 382		kfree(entry);
 383	}
 384
 385	if (dev->msi_irq_groups) {
 386		sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
 387		msi_attrs = dev->msi_irq_groups[0]->attrs;
 388		while (msi_attrs[count]) {
 389			dev_attr = container_of(msi_attrs[count],
 390						struct device_attribute, attr);
 391			kfree(dev_attr->attr.name);
 392			kfree(dev_attr);
 393			++count;
 394		}
 395		kfree(msi_attrs);
 396		kfree(dev->msi_irq_groups[0]);
 397		kfree(dev->msi_irq_groups);
 398		dev->msi_irq_groups = NULL;
 399	}
 400}
 401
 402static void pci_intx_for_msi(struct pci_dev *dev, int enable)
 403{
 404	if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
 405		pci_intx(dev, enable);
 406}
 407
 408static void __pci_restore_msi_state(struct pci_dev *dev)
 409{
 410	u16 control;
 411	struct msi_desc *entry;
 412
 413	if (!dev->msi_enabled)
 414		return;
 415
 416	entry = irq_get_msi_desc(dev->irq);
 417
 418	pci_intx_for_msi(dev, 0);
 419	pci_msi_set_enable(dev, 0);
 420	arch_restore_msi_irqs(dev);
 421
 422	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 423	msi_mask_irq(entry, msi_mask(entry->msi_attrib.multi_cap),
 424		     entry->masked);
 425	control &= ~PCI_MSI_FLAGS_QSIZE;
 426	control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE;
 427	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
 428}
 429
 430static void __pci_restore_msix_state(struct pci_dev *dev)
 431{
 432	struct msi_desc *entry;
 433
 434	if (!dev->msix_enabled)
 435		return;
 436	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
 437
 438	/* route the table */
 439	pci_intx_for_msi(dev, 0);
 440	pci_msix_clear_and_set_ctrl(dev, 0,
 441				PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL);
 442
 443	arch_restore_msi_irqs(dev);
 444	for_each_pci_msi_entry(entry, dev)
 445		msix_mask_irq(entry, entry->masked);
 446
 447	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 448}
 449
 450void pci_restore_msi_state(struct pci_dev *dev)
 451{
 452	__pci_restore_msi_state(dev);
 453	__pci_restore_msix_state(dev);
 454}
 455EXPORT_SYMBOL_GPL(pci_restore_msi_state);
 456
 457static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
 458			     char *buf)
 459{
 460	struct msi_desc *entry;
 461	unsigned long irq;
 462	int retval;
 463
 464	retval = kstrtoul(attr->attr.name, 10, &irq);
 465	if (retval)
 466		return retval;
 467
 468	entry = irq_get_msi_desc(irq);
 469	if (entry)
 470		return sprintf(buf, "%s\n",
 471				entry->msi_attrib.is_msix ? "msix" : "msi");
 472
 473	return -ENODEV;
 474}
 475
 476static int populate_msi_sysfs(struct pci_dev *pdev)
 477{
 478	struct attribute **msi_attrs;
 479	struct attribute *msi_attr;
 480	struct device_attribute *msi_dev_attr;
 481	struct attribute_group *msi_irq_group;
 482	const struct attribute_group **msi_irq_groups;
 483	struct msi_desc *entry;
 484	int ret = -ENOMEM;
 485	int num_msi = 0;
 486	int count = 0;
 487	int i;
 488
 489	/* Determine how many msi entries we have */
 490	for_each_pci_msi_entry(entry, pdev)
 491		num_msi += entry->nvec_used;
 492	if (!num_msi)
 493		return 0;
 494
 495	/* Dynamically create the MSI attributes for the PCI device */
 496	msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL);
 497	if (!msi_attrs)
 498		return -ENOMEM;
 499	for_each_pci_msi_entry(entry, pdev) {
 500		for (i = 0; i < entry->nvec_used; i++) {
 501			msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);
 502			if (!msi_dev_attr)
 503				goto error_attrs;
 504			msi_attrs[count] = &msi_dev_attr->attr;
 505
 506			sysfs_attr_init(&msi_dev_attr->attr);
 507			msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",
 508							    entry->irq + i);
 509			if (!msi_dev_attr->attr.name)
 510				goto error_attrs;
 511			msi_dev_attr->attr.mode = S_IRUGO;
 512			msi_dev_attr->show = msi_mode_show;
 513			++count;
 514		}
 515	}
 516
 517	msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL);
 518	if (!msi_irq_group)
 519		goto error_attrs;
 520	msi_irq_group->name = "msi_irqs";
 521	msi_irq_group->attrs = msi_attrs;
 522
 523	msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL);
 524	if (!msi_irq_groups)
 525		goto error_irq_group;
 526	msi_irq_groups[0] = msi_irq_group;
 527
 528	ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups);
 529	if (ret)
 530		goto error_irq_groups;
 531	pdev->msi_irq_groups = msi_irq_groups;
 532
 533	return 0;
 534
 535error_irq_groups:
 536	kfree(msi_irq_groups);
 537error_irq_group:
 538	kfree(msi_irq_group);
 539error_attrs:
 540	count = 0;
 541	msi_attr = msi_attrs[count];
 542	while (msi_attr) {
 543		msi_dev_attr = container_of(msi_attr, struct device_attribute, attr);
 544		kfree(msi_attr->name);
 545		kfree(msi_dev_attr);
 546		++count;
 547		msi_attr = msi_attrs[count];
 548	}
 549	kfree(msi_attrs);
 550	return ret;
 551}
 552
 553static struct msi_desc *
 554msi_setup_entry(struct pci_dev *dev, int nvec, const struct irq_affinity *affd)
 555{
 556	struct cpumask *masks = NULL;
 557	struct msi_desc *entry;
 558	u16 control;
 559
 560	if (affd) {
 561		masks = irq_create_affinity_masks(nvec, affd);
 562		if (!masks)
 563			pr_err("Unable to allocate affinity masks, ignoring\n");
 564	}
 565
 566	/* MSI Entry Initialization */
 567	entry = alloc_msi_entry(&dev->dev, nvec, masks);
 568	if (!entry)
 569		goto out;
 570
 571	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
 572
 573	entry->msi_attrib.is_msix	= 0;
 574	entry->msi_attrib.is_64		= !!(control & PCI_MSI_FLAGS_64BIT);
 
 575	entry->msi_attrib.entry_nr	= 0;
 576	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
 577	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
 578	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
 579	entry->msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));
 580
 581	if (control & PCI_MSI_FLAGS_64BIT)
 582		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
 583	else
 584		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;
 585
 586	/* Save the initial mask status */
 587	if (entry->msi_attrib.maskbit)
 588		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
 589
 590out:
 591	kfree(masks);
 592	return entry;
 593}
 594
 595static int msi_verify_entries(struct pci_dev *dev)
 596{
 597	struct msi_desc *entry;
 598
 599	for_each_pci_msi_entry(entry, dev) {
 600		if (!dev->no_64bit_msi || !entry->msg.address_hi)
 601			continue;
 602		dev_err(&dev->dev, "Device has broken 64-bit MSI but arch"
 603			" tried to assign one above 4G\n");
 604		return -EIO;
 605	}
 606	return 0;
 607}
 608
 609/**
 610 * msi_capability_init - configure device's MSI capability structure
 611 * @dev: pointer to the pci_dev data structure of MSI device function
 612 * @nvec: number of interrupts to allocate
 613 * @affinity: flag to indicate cpu irq affinity mask should be set
 614 *
 615 * Setup the MSI capability structure of the device with the requested
 616 * number of interrupts.  A return value of zero indicates the successful
 617 * setup of an entry with the new MSI irq.  A negative return value indicates
 618 * an error, and a positive return value indicates the number of interrupts
 619 * which could have been allocated.
 620 */
 621static int msi_capability_init(struct pci_dev *dev, int nvec,
 622			       const struct irq_affinity *affd)
 623{
 624	struct msi_desc *entry;
 625	int ret;
 626	unsigned mask;
 627
 628	pci_msi_set_enable(dev, 0);	/* Disable MSI during set up */
 629
 630	entry = msi_setup_entry(dev, nvec, affd);
 631	if (!entry)
 632		return -ENOMEM;
 633
 634	/* All MSIs are unmasked by default, Mask them all */
 635	mask = msi_mask(entry->msi_attrib.multi_cap);
 636	msi_mask_irq(entry, mask, mask);
 637
 638	list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
 639
 640	/* Configure MSI capability structure */
 641	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
 642	if (ret) {
 643		msi_mask_irq(entry, mask, ~mask);
 644		free_msi_irqs(dev);
 645		return ret;
 646	}
 647
 648	ret = msi_verify_entries(dev);
 649	if (ret) {
 650		msi_mask_irq(entry, mask, ~mask);
 651		free_msi_irqs(dev);
 652		return ret;
 653	}
 654
 655	ret = populate_msi_sysfs(dev);
 656	if (ret) {
 657		msi_mask_irq(entry, mask, ~mask);
 658		free_msi_irqs(dev);
 659		return ret;
 660	}
 661
 662	/* Set MSI enabled bits	 */
 663	pci_intx_for_msi(dev, 0);
 664	pci_msi_set_enable(dev, 1);
 665	dev->msi_enabled = 1;
 666
 667	pcibios_free_irq(dev);
 668	dev->irq = entry->irq;
 669	return 0;
 670}
 671
 672static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
 673{
 674	resource_size_t phys_addr;
 675	u32 table_offset;
 676	unsigned long flags;
 677	u8 bir;
 678
 679	pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
 680			      &table_offset);
 681	bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
 682	flags = pci_resource_flags(dev, bir);
 683	if (!flags || (flags & IORESOURCE_UNSET))
 684		return NULL;
 685
 686	table_offset &= PCI_MSIX_TABLE_OFFSET;
 687	phys_addr = pci_resource_start(dev, bir) + table_offset;
 688
 689	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
 690}
 691
 692static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
 693			      struct msix_entry *entries, int nvec,
 694			      const struct irq_affinity *affd)
 695{
 696	struct cpumask *curmsk, *masks = NULL;
 697	struct msi_desc *entry;
 698	int ret, i;
 
 699
 700	if (affd) {
 701		masks = irq_create_affinity_masks(nvec, affd);
 702		if (!masks)
 703			pr_err("Unable to allocate affinity masks, ignoring\n");
 704	}
 705
 706	for (i = 0, curmsk = masks; i < nvec; i++) {
 707		entry = alloc_msi_entry(&dev->dev, 1, curmsk);
 708		if (!entry) {
 709			if (!i)
 710				iounmap(base);
 711			else
 712				free_msi_irqs(dev);
 713			/* No enough memory. Don't try again */
 714			ret = -ENOMEM;
 715			goto out;
 716		}
 717
 718		entry->msi_attrib.is_msix	= 1;
 719		entry->msi_attrib.is_64		= 1;
 720		if (entries)
 721			entry->msi_attrib.entry_nr = entries[i].entry;
 722		else
 723			entry->msi_attrib.entry_nr = i;
 
 
 
 
 724		entry->msi_attrib.default_irq	= dev->irq;
 725		entry->mask_base		= base;
 726
 727		list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
 728		if (masks)
 729			curmsk++;
 730	}
 731	ret = 0;
 732out:
 733	kfree(masks);
 734	return 0;
 735}
 736
 737static void msix_program_entries(struct pci_dev *dev,
 738				 struct msix_entry *entries)
 739{
 740	struct msi_desc *entry;
 741	int i = 0;
 
 742
 743	for_each_pci_msi_entry(entry, dev) {
 744		if (entries)
 745			entries[i++].vector = entry->irq;
 746		entry->masked = readl(pci_msix_desc_addr(entry) +
 747				PCI_MSIX_ENTRY_VECTOR_CTRL);
 
 
 
 
 
 
 748		msix_mask_irq(entry, 1);
 749	}
 750}
 751
 752/**
 753 * msix_capability_init - configure device's MSI-X capability
 754 * @dev: pointer to the pci_dev data structure of MSI-X device function
 755 * @entries: pointer to an array of struct msix_entry entries
 756 * @nvec: number of @entries
 757 * @affd: Optional pointer to enable automatic affinity assignement
 758 *
 759 * Setup the MSI-X capability structure of device function with a
 760 * single MSI-X irq. A return of zero indicates the successful setup of
 761 * requested MSI-X entries with allocated irqs or non-zero for otherwise.
 762 **/
 763static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
 764				int nvec, const struct irq_affinity *affd)
 765{
 766	int ret;
 767	u16 control;
 768	void __iomem *base;
 769
 770	/* Ensure MSI-X is disabled while it is set up */
 771	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
 772
 773	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 774	/* Request & Map MSI-X table region */
 775	base = msix_map_region(dev, msix_table_size(control));
 776	if (!base)
 777		return -ENOMEM;
 778
 779	ret = msix_setup_entries(dev, base, entries, nvec, affd);
 780	if (ret)
 781		return ret;
 782
 783	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
 784	if (ret)
 785		goto out_avail;
 786
 787	/* Check if all MSI entries honor device restrictions */
 788	ret = msi_verify_entries(dev);
 789	if (ret)
 790		goto out_free;
 791
 792	/*
 793	 * Some devices require MSI-X to be enabled before we can touch the
 794	 * MSI-X registers.  We need to mask all the vectors to prevent
 795	 * interrupts coming in before they're fully set up.
 796	 */
 797	pci_msix_clear_and_set_ctrl(dev, 0,
 798				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
 799
 800	msix_program_entries(dev, entries);
 801
 802	ret = populate_msi_sysfs(dev);
 803	if (ret)
 804		goto out_free;
 805
 806	/* Set MSI-X enabled bits and unmask the function */
 807	pci_intx_for_msi(dev, 0);
 808	dev->msix_enabled = 1;
 809	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
 810
 811	pcibios_free_irq(dev);
 812	return 0;
 813
 814out_avail:
 815	if (ret < 0) {
 816		/*
 817		 * If we had some success, report the number of irqs
 818		 * we succeeded in setting up.
 819		 */
 820		struct msi_desc *entry;
 821		int avail = 0;
 822
 823		for_each_pci_msi_entry(entry, dev) {
 824			if (entry->irq != 0)
 825				avail++;
 826		}
 827		if (avail != 0)
 828			ret = avail;
 829	}
 830
 831out_free:
 832	free_msi_irqs(dev);
 833
 834	return ret;
 835}
 836
 837/**
 838 * pci_msi_supported - check whether MSI may be enabled on a device
 839 * @dev: pointer to the pci_dev data structure of MSI device function
 840 * @nvec: how many MSIs have been requested ?
 841 *
 842 * Look at global flags, the device itself, and its parent buses
 843 * to determine if MSI/-X are supported for the device. If MSI/-X is
 844 * supported return 1, else return 0.
 845 **/
 846static int pci_msi_supported(struct pci_dev *dev, int nvec)
 847{
 848	struct pci_bus *bus;
 849
 850	/* MSI must be globally enabled and supported by the device */
 851	if (!pci_msi_enable)
 852		return 0;
 853
 854	if (!dev || dev->no_msi || dev->current_state != PCI_D0)
 855		return 0;
 856
 857	/*
 858	 * You can't ask to have 0 or less MSIs configured.
 859	 *  a) it's stupid ..
 860	 *  b) the list manipulation code assumes nvec >= 1.
 861	 */
 862	if (nvec < 1)
 863		return 0;
 864
 865	/*
 866	 * Any bridge which does NOT route MSI transactions from its
 867	 * secondary bus to its primary bus must set NO_MSI flag on
 868	 * the secondary pci_bus.
 869	 * We expect only arch-specific PCI host bus controller driver
 870	 * or quirks for specific PCI bridges to be setting NO_MSI.
 871	 */
 872	for (bus = dev->bus; bus; bus = bus->parent)
 873		if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
 874			return 0;
 875
 876	return 1;
 877}
 878
 879/**
 880 * pci_msi_vec_count - Return the number of MSI vectors a device can send
 881 * @dev: device to report about
 882 *
 883 * This function returns the number of MSI vectors a device requested via
 884 * Multiple Message Capable register. It returns a negative errno if the
 885 * device is not capable sending MSI interrupts. Otherwise, the call succeeds
 886 * and returns a power of two, up to a maximum of 2^5 (32), according to the
 887 * MSI specification.
 888 **/
 889int pci_msi_vec_count(struct pci_dev *dev)
 890{
 891	int ret;
 892	u16 msgctl;
 893
 894	if (!dev->msi_cap)
 895		return -EINVAL;
 896
 897	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl);
 898	ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);
 899
 900	return ret;
 901}
 902EXPORT_SYMBOL(pci_msi_vec_count);
 903
 904void pci_msi_shutdown(struct pci_dev *dev)
 905{
 906	struct msi_desc *desc;
 907	u32 mask;
 908
 909	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 910		return;
 911
 912	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
 913	desc = first_pci_msi_entry(dev);
 914
 915	pci_msi_set_enable(dev, 0);
 916	pci_intx_for_msi(dev, 1);
 917	dev->msi_enabled = 0;
 918
 919	/* Return the device with MSI unmasked as initial states */
 920	mask = msi_mask(desc->msi_attrib.multi_cap);
 921	/* Keep cached state to be restored */
 922	__pci_msi_desc_mask_irq(desc, mask, ~mask);
 923
 924	/* Restore dev->irq to its default pin-assertion irq */
 925	dev->irq = desc->msi_attrib.default_irq;
 926	pcibios_alloc_irq(dev);
 927}
 928
 929void pci_disable_msi(struct pci_dev *dev)
 930{
 931	if (!pci_msi_enable || !dev || !dev->msi_enabled)
 932		return;
 933
 934	pci_msi_shutdown(dev);
 935	free_msi_irqs(dev);
 936}
 937EXPORT_SYMBOL(pci_disable_msi);
 938
 939/**
 940 * pci_msix_vec_count - return the number of device's MSI-X table entries
 941 * @dev: pointer to the pci_dev data structure of MSI-X device function
 942 * This function returns the number of device's MSI-X table entries and
 943 * therefore the number of MSI-X vectors device is capable of sending.
 944 * It returns a negative errno if the device is not capable of sending MSI-X
 945 * interrupts.
 946 **/
 947int pci_msix_vec_count(struct pci_dev *dev)
 948{
 949	u16 control;
 950
 951	if (!dev->msix_cap)
 952		return -EINVAL;
 953
 954	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
 955	return msix_table_size(control);
 956}
 957EXPORT_SYMBOL(pci_msix_vec_count);
 958
 959static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
 960			     int nvec, const struct irq_affinity *affd)
 961{
 962	int nr_entries;
 963	int i, j;
 964
 965	if (!pci_msi_supported(dev, nvec))
 966		return -EINVAL;
 967
 968	nr_entries = pci_msix_vec_count(dev);
 969	if (nr_entries < 0)
 970		return nr_entries;
 971	if (nvec > nr_entries)
 972		return nr_entries;
 973
 974	if (entries) {
 975		/* Check for any invalid entries */
 976		for (i = 0; i < nvec; i++) {
 977			if (entries[i].entry >= nr_entries)
 978				return -EINVAL;		/* invalid entry */
 979			for (j = i + 1; j < nvec; j++) {
 980				if (entries[i].entry == entries[j].entry)
 981					return -EINVAL;	/* duplicate entry */
 982			}
 983		}
 984	}
 985	WARN_ON(!!dev->msix_enabled);
 986
 987	/* Check whether driver already requested for MSI irq */
 988	if (dev->msi_enabled) {
 989		dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
 990		return -EINVAL;
 991	}
 992	return msix_capability_init(dev, entries, nvec, affd);
 993}
 994
 995/**
 996 * pci_enable_msix - configure device's MSI-X capability structure
 997 * @dev: pointer to the pci_dev data structure of MSI-X device function
 998 * @entries: pointer to an array of MSI-X entries (optional)
 999 * @nvec: number of MSI-X irqs requested for allocation by device driver
1000 *
1001 * Setup the MSI-X capability structure of device function with the number
1002 * of requested irqs upon its software driver call to request for
1003 * MSI-X mode enabled on its hardware device function. A return of zero
1004 * indicates the successful configuration of MSI-X capability structure
1005 * with new allocated MSI-X irqs. A return of < 0 indicates a failure.
1006 * Or a return of > 0 indicates that driver request is exceeding the number
1007 * of irqs or MSI-X vectors available. Driver should use the returned value to
1008 * re-send its request.
1009 **/
1010int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
1011{
1012	return __pci_enable_msix(dev, entries, nvec, NULL);
1013}
1014EXPORT_SYMBOL(pci_enable_msix);
1015
1016void pci_msix_shutdown(struct pci_dev *dev)
1017{
1018	struct msi_desc *entry;
1019
1020	if (!pci_msi_enable || !dev || !dev->msix_enabled)
1021		return;
1022
 
 
 
 
 
1023	/* Return the device with MSI-X masked as initial states */
1024	for_each_pci_msi_entry(entry, dev) {
1025		/* Keep cached states to be restored */
1026		__pci_msix_desc_mask_irq(entry, 1);
1027	}
1028
1029	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1030	pci_intx_for_msi(dev, 1);
1031	dev->msix_enabled = 0;
1032	pcibios_alloc_irq(dev);
1033}
1034
1035void pci_disable_msix(struct pci_dev *dev)
1036{
1037	if (!pci_msi_enable || !dev || !dev->msix_enabled)
1038		return;
1039
1040	pci_msix_shutdown(dev);
1041	free_msi_irqs(dev);
1042}
1043EXPORT_SYMBOL(pci_disable_msix);
1044
1045void pci_no_msi(void)
1046{
1047	pci_msi_enable = 0;
1048}
1049
1050/**
1051 * pci_msi_enabled - is MSI enabled?
1052 *
1053 * Returns true if MSI has not been disabled by the command-line option
1054 * pci=nomsi.
1055 **/
1056int pci_msi_enabled(void)
1057{
1058	return pci_msi_enable;
1059}
1060EXPORT_SYMBOL(pci_msi_enabled);
1061
1062static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
1063				  const struct irq_affinity *affd)
1064{
1065	int nvec;
1066	int rc;
1067
1068	if (!pci_msi_supported(dev, minvec))
1069		return -EINVAL;
1070
1071	WARN_ON(!!dev->msi_enabled);
1072
1073	/* Check whether driver already requested MSI-X irqs */
1074	if (dev->msix_enabled) {
1075		dev_info(&dev->dev,
1076			 "can't enable MSI (MSI-X already enabled)\n");
1077		return -EINVAL;
1078	}
1079
1080	if (maxvec < minvec)
1081		return -ERANGE;
1082
 
 
 
1083	nvec = pci_msi_vec_count(dev);
1084	if (nvec < 0)
1085		return nvec;
1086	if (nvec < minvec)
1087		return -EINVAL;
1088
1089	if (nvec > maxvec)
1090		nvec = maxvec;
1091
1092	for (;;) {
1093		if (affd) {
1094			nvec = irq_calc_affinity_vectors(nvec, affd);
1095			if (nvec < minvec)
1096				return -ENOSPC;
1097		}
1098
1099		rc = msi_capability_init(dev, nvec, affd);
1100		if (rc == 0)
1101			return nvec;
1102
1103		if (rc < 0)
1104			return rc;
1105		if (rc < minvec)
1106			return -ENOSPC;
1107
1108		nvec = rc;
1109	}
1110}
1111
1112/**
1113 * pci_enable_msi_range - configure device's MSI capability structure
1114 * @dev: device to configure
1115 * @minvec: minimal number of interrupts to configure
1116 * @maxvec: maximum number of interrupts to configure
1117 *
1118 * This function tries to allocate a maximum possible number of interrupts in a
1119 * range between @minvec and @maxvec. It returns a negative errno if an error
1120 * occurs. If it succeeds, it returns the actual number of interrupts allocated
1121 * and updates the @dev's irq member to the lowest new interrupt number;
1122 * the other interrupt numbers allocated to this device are consecutive.
1123 **/
1124int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
1125{
1126	return __pci_enable_msi_range(dev, minvec, maxvec, NULL);
 
 
 
1127}
1128EXPORT_SYMBOL(pci_enable_msi_range);
1129
1130static int __pci_enable_msix_range(struct pci_dev *dev,
1131				   struct msix_entry *entries, int minvec,
1132				   int maxvec, const struct irq_affinity *affd)
 
1133{
1134	int rc, nvec = maxvec;
1135
1136	if (maxvec < minvec)
1137		return -ERANGE;
1138
 
 
 
1139	for (;;) {
1140		if (affd) {
1141			nvec = irq_calc_affinity_vectors(nvec, affd);
1142			if (nvec < minvec)
1143				return -ENOSPC;
1144		}
1145
1146		rc = __pci_enable_msix(dev, entries, nvec, affd);
1147		if (rc == 0)
1148			return nvec;
1149
1150		if (rc < 0)
1151			return rc;
1152		if (rc < minvec)
1153			return -ENOSPC;
1154
1155		nvec = rc;
1156	}
1157}
1158
1159/**
1160 * pci_enable_msix_range - configure device's MSI-X capability structure
1161 * @dev: pointer to the pci_dev data structure of MSI-X device function
1162 * @entries: pointer to an array of MSI-X entries
1163 * @minvec: minimum number of MSI-X irqs requested
1164 * @maxvec: maximum number of MSI-X irqs requested
1165 *
1166 * Setup the MSI-X capability structure of device function with a maximum
1167 * possible number of interrupts in the range between @minvec and @maxvec
1168 * upon its software driver call to request for MSI-X mode enabled on its
1169 * hardware device function. It returns a negative errno if an error occurs.
1170 * If it succeeds, it returns the actual number of interrupts allocated and
1171 * indicates the successful configuration of MSI-X capability structure
1172 * with new allocated MSI-X interrupts.
1173 **/
1174int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
1175		int minvec, int maxvec)
1176{
1177	return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL);
1178}
1179EXPORT_SYMBOL(pci_enable_msix_range);
1180
1181/**
1182 * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
1183 * @dev:		PCI device to operate on
1184 * @min_vecs:		minimum number of vectors required (must be >= 1)
1185 * @max_vecs:		maximum (desired) number of vectors
1186 * @flags:		flags or quirks for the allocation
1187 * @affd:		optional description of the affinity requirements
1188 *
1189 * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
1190 * vectors if available, and fall back to a single legacy vector
1191 * if neither is available.  Return the number of vectors allocated,
1192 * (which might be smaller than @max_vecs) if successful, or a negative
1193 * error code on error. If less than @min_vecs interrupt vectors are
1194 * available for @dev the function will fail with -ENOSPC.
1195 *
1196 * To get the Linux IRQ number used for a vector that can be passed to
1197 * request_irq() use the pci_irq_vector() helper.
1198 */
1199int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
1200				   unsigned int max_vecs, unsigned int flags,
1201				   const struct irq_affinity *affd)
1202{
1203	static const struct irq_affinity msi_default_affd;
1204	int vecs = -ENOSPC;
 
1205
1206	if (flags & PCI_IRQ_AFFINITY) {
1207		if (!affd)
1208			affd = &msi_default_affd;
1209
1210		if (affd->pre_vectors + affd->post_vectors > min_vecs)
1211			return -EINVAL;
1212
1213		/*
1214		 * If there aren't any vectors left after applying the pre/post
1215		 * vectors don't bother with assigning affinity.
1216		 */
1217		if (affd->pre_vectors + affd->post_vectors == min_vecs)
1218			affd = NULL;
1219	} else {
1220		if (WARN_ON(affd))
1221			affd = NULL;
1222	}
1223
1224	if (flags & PCI_IRQ_MSIX) {
1225		vecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs,
1226				affd);
1227		if (vecs > 0)
1228			return vecs;
1229	}
1230
1231	if (flags & PCI_IRQ_MSI) {
1232		vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd);
1233		if (vecs > 0)
1234			return vecs;
1235	}
1236
1237	/* use legacy irq if allowed */
1238	if ((flags & PCI_IRQ_LEGACY) && min_vecs == 1) {
1239		pci_intx(dev, 1);
1240		return 1;
 
 
 
 
 
 
 
 
 
 
1241	}
1242
1243	return vecs;
 
 
1244}
1245EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
1246
1247/**
1248 * pci_free_irq_vectors - free previously allocated IRQs for a device
1249 * @dev:		PCI device to operate on
1250 *
1251 * Undoes the allocations and enabling in pci_alloc_irq_vectors().
1252 */
1253void pci_free_irq_vectors(struct pci_dev *dev)
1254{
1255	pci_disable_msix(dev);
1256	pci_disable_msi(dev);
1257}
1258EXPORT_SYMBOL(pci_free_irq_vectors);
1259
1260/**
1261 * pci_irq_vector - return Linux IRQ number of a device vector
1262 * @dev: PCI device to operate on
1263 * @nr: device-relative interrupt vector index (0-based).
1264 */
1265int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
1266{
1267	if (dev->msix_enabled) {
1268		struct msi_desc *entry;
1269		int i = 0;
1270
1271		for_each_pci_msi_entry(entry, dev) {
1272			if (i == nr)
1273				return entry->irq;
1274			i++;
1275		}
1276		WARN_ON_ONCE(1);
1277		return -EINVAL;
1278	}
1279
1280	if (dev->msi_enabled) {
1281		struct msi_desc *entry = first_pci_msi_entry(dev);
1282
1283		if (WARN_ON_ONCE(nr >= entry->nvec_used))
1284			return -EINVAL;
1285	} else {
1286		if (WARN_ON_ONCE(nr > 0))
1287			return -EINVAL;
1288	}
1289
1290	return dev->irq + nr;
1291}
1292EXPORT_SYMBOL(pci_irq_vector);
1293
1294/**
1295 * pci_irq_get_affinity - return the affinity of a particular msi vector
1296 * @dev:	PCI device to operate on
1297 * @nr:		device-relative interrupt vector index (0-based).
1298 */
1299const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
1300{
1301	if (dev->msix_enabled) {
1302		struct msi_desc *entry;
1303		int i = 0;
1304
1305		for_each_pci_msi_entry(entry, dev) {
1306			if (i == nr)
1307				return entry->affinity;
1308			i++;
1309		}
1310		WARN_ON_ONCE(1);
1311		return NULL;
1312	} else if (dev->msi_enabled) {
1313		struct msi_desc *entry = first_pci_msi_entry(dev);
1314
1315		if (WARN_ON_ONCE(!entry || !entry->affinity ||
1316				 nr >= entry->nvec_used))
1317			return NULL;
1318
1319		return &entry->affinity[nr];
1320	} else {
1321		return cpu_possible_mask;
1322	}
1323}
1324EXPORT_SYMBOL(pci_irq_get_affinity);
1325
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1326struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc)
1327{
1328	return to_pci_dev(desc->dev);
1329}
1330EXPORT_SYMBOL(msi_desc_to_pci_dev);
1331
1332void *msi_desc_to_pci_sysdata(struct msi_desc *desc)
1333{
1334	struct pci_dev *dev = msi_desc_to_pci_dev(desc);
1335
1336	return dev->bus->sysdata;
1337}
1338EXPORT_SYMBOL_GPL(msi_desc_to_pci_sysdata);
1339
1340#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
1341/**
1342 * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
1343 * @irq_data:	Pointer to interrupt data of the MSI interrupt
1344 * @msg:	Pointer to the message
1345 */
1346void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
1347{
1348	struct msi_desc *desc = irq_data_get_msi_desc(irq_data);
1349
1350	/*
1351	 * For MSI-X desc->irq is always equal to irq_data->irq. For
1352	 * MSI only the first interrupt of MULTI MSI passes the test.
1353	 */
1354	if (desc->irq == irq_data->irq)
1355		__pci_write_msi_msg(desc, msg);
1356}
1357
1358/**
1359 * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
1360 * @dev:	Pointer to the PCI device
1361 * @desc:	Pointer to the msi descriptor
1362 *
1363 * The ID number is only used within the irqdomain.
1364 */
1365irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
1366					  struct msi_desc *desc)
1367{
1368	return (irq_hw_number_t)desc->msi_attrib.entry_nr |
1369		PCI_DEVID(dev->bus->number, dev->devfn) << 11 |
1370		(pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27;
1371}
1372
1373static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
1374{
1375	return !desc->msi_attrib.is_msix && desc->nvec_used > 1;
1376}
1377
1378/**
1379 * pci_msi_domain_check_cap - Verify that @domain supports the capabilities for @dev
 
1380 * @domain:	The interrupt domain to check
1381 * @info:	The domain info for verification
1382 * @dev:	The device to check
1383 *
1384 * Returns:
1385 *  0 if the functionality is supported
1386 *  1 if Multi MSI is requested, but the domain does not support it
1387 *  -ENOTSUPP otherwise
1388 */
1389int pci_msi_domain_check_cap(struct irq_domain *domain,
1390			     struct msi_domain_info *info, struct device *dev)
1391{
1392	struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));
1393
1394	/* Special handling to support pci_enable_msi_range() */
1395	if (pci_msi_desc_is_multi_msi(desc) &&
1396	    !(info->flags & MSI_FLAG_MULTI_PCI_MSI))
1397		return 1;
1398	else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX))
1399		return -ENOTSUPP;
1400
1401	return 0;
1402}
1403
1404static int pci_msi_domain_handle_error(struct irq_domain *domain,
1405				       struct msi_desc *desc, int error)
1406{
1407	/* Special handling to support pci_enable_msi_range() */
1408	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
1409		return 1;
1410
1411	return error;
1412}
1413
1414#ifdef GENERIC_MSI_DOMAIN_OPS
1415static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
1416				    struct msi_desc *desc)
1417{
1418	arg->desc = desc;
1419	arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc),
1420					       desc);
1421}
1422#else
1423#define pci_msi_domain_set_desc		NULL
1424#endif
1425
1426static struct msi_domain_ops pci_msi_domain_ops_default = {
1427	.set_desc	= pci_msi_domain_set_desc,
1428	.msi_check	= pci_msi_domain_check_cap,
1429	.handle_error	= pci_msi_domain_handle_error,
1430};
1431
1432static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
1433{
1434	struct msi_domain_ops *ops = info->ops;
1435
1436	if (ops == NULL) {
1437		info->ops = &pci_msi_domain_ops_default;
1438	} else {
1439		if (ops->set_desc == NULL)
1440			ops->set_desc = pci_msi_domain_set_desc;
1441		if (ops->msi_check == NULL)
1442			ops->msi_check = pci_msi_domain_check_cap;
1443		if (ops->handle_error == NULL)
1444			ops->handle_error = pci_msi_domain_handle_error;
1445	}
1446}
1447
1448static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
1449{
1450	struct irq_chip *chip = info->chip;
1451
1452	BUG_ON(!chip);
1453	if (!chip->irq_write_msi_msg)
1454		chip->irq_write_msi_msg = pci_msi_domain_write_msg;
1455	if (!chip->irq_mask)
1456		chip->irq_mask = pci_msi_mask_irq;
1457	if (!chip->irq_unmask)
1458		chip->irq_unmask = pci_msi_unmask_irq;
1459}
1460
1461/**
1462 * pci_msi_create_irq_domain - Create a MSI interrupt domain
1463 * @fwnode:	Optional fwnode of the interrupt controller
1464 * @info:	MSI domain info
1465 * @parent:	Parent irq domain
1466 *
1467 * Updates the domain and chip ops and creates a MSI interrupt domain.
1468 *
1469 * Returns:
1470 * A domain pointer or NULL in case of failure.
1471 */
1472struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
1473					     struct msi_domain_info *info,
1474					     struct irq_domain *parent)
1475{
1476	struct irq_domain *domain;
1477
 
 
 
1478	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
1479		pci_msi_domain_update_dom_ops(info);
1480	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
1481		pci_msi_domain_update_chip_ops(info);
1482
1483	info->flags |= MSI_FLAG_ACTIVATE_EARLY;
 
 
 
 
 
1484
1485	domain = msi_create_irq_domain(fwnode, info, parent);
1486	if (!domain)
1487		return NULL;
1488
1489	domain->bus_token = DOMAIN_BUS_PCI_MSI;
1490	return domain;
1491}
1492EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain);
1493
1494/**
1495 * pci_msi_domain_alloc_irqs - Allocate interrupts for @dev in @domain
1496 * @domain:	The interrupt domain to allocate from
1497 * @dev:	The device for which to allocate
1498 * @nvec:	The number of interrupts to allocate
1499 * @type:	Unused to allow simpler migration from the arch_XXX interfaces
1500 *
1501 * Returns:
1502 * A virtual interrupt number or an error code in case of failure
1503 */
1504int pci_msi_domain_alloc_irqs(struct irq_domain *domain, struct pci_dev *dev,
1505			      int nvec, int type)
1506{
1507	return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
1508}
1509
1510/**
1511 * pci_msi_domain_free_irqs - Free interrupts for @dev in @domain
1512 * @domain:	The interrupt domain
1513 * @dev:	The device for which to free interrupts
1514 */
1515void pci_msi_domain_free_irqs(struct irq_domain *domain, struct pci_dev *dev)
1516{
1517	msi_domain_free_irqs(domain, &dev->dev);
1518}
1519
1520/**
1521 * pci_msi_create_default_irq_domain - Create a default MSI interrupt domain
1522 * @fwnode:	Optional fwnode of the interrupt controller
1523 * @info:	MSI domain info
1524 * @parent:	Parent irq domain
1525 *
1526 * Returns: A domain pointer or NULL in case of failure. If successful
1527 * the default PCI/MSI irqdomain pointer is updated.
1528 */
1529struct irq_domain *pci_msi_create_default_irq_domain(struct fwnode_handle *fwnode,
1530		struct msi_domain_info *info, struct irq_domain *parent)
1531{
1532	struct irq_domain *domain;
1533
1534	mutex_lock(&pci_msi_domain_lock);
1535	if (pci_msi_default_domain) {
1536		pr_err("PCI: default irq domain for PCI MSI has already been created.\n");
1537		domain = NULL;
1538	} else {
1539		domain = pci_msi_create_irq_domain(fwnode, info, parent);
1540		pci_msi_default_domain = domain;
1541	}
1542	mutex_unlock(&pci_msi_domain_lock);
1543
1544	return domain;
1545}
1546
1547static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
1548{
1549	u32 *pa = data;
 
 
 
 
1550
1551	*pa = alias;
1552	return 0;
1553}
 
1554/**
1555 * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
1556 * @domain:	The interrupt domain
1557 * @pdev:	The PCI device.
1558 *
1559 * The RID for a device is formed from the alias, with a firmware
1560 * supplied mapping applied
1561 *
1562 * Returns: The RID.
1563 */
1564u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
1565{
1566	struct device_node *of_node;
1567	u32 rid = 0;
1568
1569	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
1570
1571	of_node = irq_domain_get_of_node(domain);
1572	rid = of_node ? of_msi_map_rid(&pdev->dev, of_node, rid) :
1573			iort_msi_map_rid(&pdev->dev, rid);
1574
1575	return rid;
1576}
1577
1578/**
1579 * pci_msi_get_device_domain - Get the MSI domain for a given PCI device
1580 * @pdev:	The PCI device
1581 *
1582 * Use the firmware data to find a device-specific MSI domain
1583 * (i.e. not one that is ste as a default).
1584 *
1585 * Returns: The coresponding MSI domain or NULL if none has been found.
1586 */
1587struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
1588{
1589	struct irq_domain *dom;
1590	u32 rid = 0;
1591
1592	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
1593	dom = of_msi_map_get_device_domain(&pdev->dev, rid);
1594	if (!dom)
1595		dom = iort_get_device_domain(&pdev->dev, rid);
1596	return dom;
1597}
1598#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */