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