msi.c 39.2 KB
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// SPDX-License-Identifier: GPL-2.0
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/*
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 * PCI Message Signaled Interrupt (MSI)
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 *
 * Copyright (C) 2003-2004 Intel
 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
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 * Copyright (C) 2016 Christoph Hellwig.
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 */

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#include <linux/err.h>
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#include <linux/mm.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
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#include <linux/export.h>
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#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
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#include <linux/msi.h>
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#include <linux/smp.h>
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#include <linux/errno.h>
#include <linux/io.h>
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#include <linux/acpi_iort.h>
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#include <linux/slab.h>
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#include <linux/irqdomain.h>
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#include <linux/of_irq.h>
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#include "pci.h"

static int pci_msi_enable = 1;
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int pci_msi_ignore_mask;
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#define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)

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#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
	struct irq_domain *domain;

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	domain = dev_get_msi_domain(&dev->dev);
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	if (domain && irq_domain_is_hierarchy(domain))
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		return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
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	return arch_setup_msi_irqs(dev, nvec, type);
}

static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
{
	struct irq_domain *domain;

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	domain = dev_get_msi_domain(&dev->dev);
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	if (domain && irq_domain_is_hierarchy(domain))
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		msi_domain_free_irqs(domain, &dev->dev);
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	else
		arch_teardown_msi_irqs(dev);
}
#else
#define pci_msi_setup_msi_irqs		arch_setup_msi_irqs
#define pci_msi_teardown_msi_irqs	arch_teardown_msi_irqs
#endif
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/* Arch hooks */

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int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
{
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	struct msi_controller *chip = dev->bus->msi;
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	int err;

	if (!chip || !chip->setup_irq)
		return -EINVAL;

	err = chip->setup_irq(chip, dev, desc);
	if (err < 0)
		return err;

	irq_set_chip_data(desc->irq, chip);

	return 0;
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}

void __weak arch_teardown_msi_irq(unsigned int irq)
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{
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	struct msi_controller *chip = irq_get_chip_data(irq);
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	if (!chip || !chip->teardown_irq)
		return;

	chip->teardown_irq(chip, irq);
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}

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int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
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{
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	struct msi_controller *chip = dev->bus->msi;
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	struct msi_desc *entry;
	int ret;

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	if (chip && chip->setup_irqs)
		return chip->setup_irqs(chip, dev, nvec, type);
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	/*
	 * If an architecture wants to support multiple MSI, it needs to
	 * override arch_setup_msi_irqs()
	 */
	if (type == PCI_CAP_ID_MSI && nvec > 1)
		return 1;

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	for_each_pci_msi_entry(entry, dev) {
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		ret = arch_setup_msi_irq(dev, entry);
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		if (ret < 0)
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			return ret;
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		if (ret > 0)
			return -ENOSPC;
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	}

	return 0;
}
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/*
 * We have a default implementation available as a separate non-weak
 * function, as it is used by the Xen x86 PCI code
 */
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void default_teardown_msi_irqs(struct pci_dev *dev)
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{
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	int i;
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	struct msi_desc *entry;

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	for_each_pci_msi_entry(entry, dev)
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		if (entry->irq)
			for (i = 0; i < entry->nvec_used; i++)
				arch_teardown_msi_irq(entry->irq + i);
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}

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void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
{
	return default_teardown_msi_irqs(dev);
}
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static void default_restore_msi_irq(struct pci_dev *dev, int irq)
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{
	struct msi_desc *entry;

	entry = NULL;
	if (dev->msix_enabled) {
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		for_each_pci_msi_entry(entry, dev) {
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			if (irq == entry->irq)
				break;
		}
	} else if (dev->msi_enabled)  {
		entry = irq_get_msi_desc(irq);
	}

	if (entry)
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		__pci_write_msi_msg(entry, &entry->msg);
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}
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void __weak arch_restore_msi_irqs(struct pci_dev *dev)
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{
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	return default_restore_msi_irqs(dev);
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}
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static inline __attribute_const__ u32 msi_mask(unsigned x)
{
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	/* Don't shift by >= width of type */
	if (x >= 5)
		return 0xffffffff;
	return (1 << (1 << x)) - 1;
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}

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/*
 * PCI 2.3 does not specify mask bits for each MSI interrupt.  Attempting to
 * mask all MSI interrupts by clearing the MSI enable bit does not work
 * reliably as devices without an INTx disable bit will then generate a
 * level IRQ which will never be cleared.
 */
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u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
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{
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	u32 mask_bits = desc->masked;
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	if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit)
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		return 0;
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	mask_bits &= ~mask;
	mask_bits |= flag;
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	pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->mask_pos,
			       mask_bits);
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	return mask_bits;
}

static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
{
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	desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag);
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}

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static void __iomem *pci_msix_desc_addr(struct msi_desc *desc)
{
	return desc->mask_base +
		desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
}

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/*
 * This internal function does not flush PCI writes to the device.
 * All users must ensure that they read from the device before either
 * assuming that the device state is up to date, or returning out of this
 * file.  This saves a few milliseconds when initialising devices with lots
 * of MSI-X interrupts.
 */
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u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
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{
	u32 mask_bits = desc->masked;
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	if (pci_msi_ignore_mask)
		return 0;

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	mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
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	if (flag & PCI_MSIX_ENTRY_CTRL_MASKBIT)
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		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
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	writel(mask_bits, pci_msix_desc_addr(desc) + PCI_MSIX_ENTRY_VECTOR_CTRL);
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	return mask_bits;
}

static void msix_mask_irq(struct msi_desc *desc, u32 flag)
{
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	desc->masked = __pci_msix_desc_mask_irq(desc, flag);
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}
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static void msi_set_mask_bit(struct irq_data *data, u32 flag)
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{
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	struct msi_desc *desc = irq_data_get_msi_desc(data);
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	if (desc->msi_attrib.is_msix) {
		msix_mask_irq(desc, flag);
		readl(desc->mask_base);		/* Flush write to device */
	} else {
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		unsigned offset = data->irq - desc->irq;
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		msi_mask_irq(desc, 1 << offset, flag << offset);
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	}
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}

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/**
 * pci_msi_mask_irq - Generic irq chip callback to mask PCI/MSI interrupts
 * @data:	pointer to irqdata associated to that interrupt
 */
void pci_msi_mask_irq(struct irq_data *data)
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{
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	msi_set_mask_bit(data, 1);
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}
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EXPORT_SYMBOL_GPL(pci_msi_mask_irq);
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/**
 * pci_msi_unmask_irq - Generic irq chip callback to unmask PCI/MSI interrupts
 * @data:	pointer to irqdata associated to that interrupt
 */
void pci_msi_unmask_irq(struct irq_data *data)
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{
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	msi_set_mask_bit(data, 0);
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}
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EXPORT_SYMBOL_GPL(pci_msi_unmask_irq);
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void default_restore_msi_irqs(struct pci_dev *dev)
{
	struct msi_desc *entry;

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	for_each_pci_msi_entry(entry, dev)
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		default_restore_msi_irq(dev, entry->irq);
}

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void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
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{
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	struct pci_dev *dev = msi_desc_to_pci_dev(entry);

	BUG_ON(dev->current_state != PCI_D0);
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	if (entry->msi_attrib.is_msix) {
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		void __iomem *base = pci_msix_desc_addr(entry);
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		msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
		msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
		msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
	} else {
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		int pos = dev->msi_cap;
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		u16 data;

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		pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
				      &msg->address_lo);
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		if (entry->msi_attrib.is_64) {
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			pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
					      &msg->address_hi);
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			pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data);
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		} else {
			msg->address_hi = 0;
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			pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data);
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		}
		msg->data = data;
	}
}

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void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
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{
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	struct pci_dev *dev = msi_desc_to_pci_dev(entry);

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	if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) {
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		/* Don't touch the hardware now */
	} else if (entry->msi_attrib.is_msix) {
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		void __iomem *base = pci_msix_desc_addr(entry);
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		writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
		writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
		writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
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	} else {
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		int pos = dev->msi_cap;
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		u16 msgctl;

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		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
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		msgctl &= ~PCI_MSI_FLAGS_QSIZE;
		msgctl |= entry->msi_attrib.multiple << 4;
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		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl);
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		pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO,
				       msg->address_lo);
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		if (entry->msi_attrib.is_64) {
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			pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI,
					       msg->address_hi);
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			pci_write_config_word(dev, pos + PCI_MSI_DATA_64,
					      msg->data);
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		} else {
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			pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
					      msg->data);
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		}
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	}
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	entry->msg = *msg;
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}
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void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
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{
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	struct msi_desc *entry = irq_get_msi_desc(irq);
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	__pci_write_msi_msg(entry, msg);
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}
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EXPORT_SYMBOL_GPL(pci_write_msi_msg);
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static void free_msi_irqs(struct pci_dev *dev)
{
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	struct list_head *msi_list = dev_to_msi_list(&dev->dev);
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	struct msi_desc *entry, *tmp;
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	struct attribute **msi_attrs;
	struct device_attribute *dev_attr;
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	int i, count = 0;
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	for_each_pci_msi_entry(entry, dev)
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		if (entry->irq)
			for (i = 0; i < entry->nvec_used; i++)
				BUG_ON(irq_has_action(entry->irq + i));
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	pci_msi_teardown_msi_irqs(dev);
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	list_for_each_entry_safe(entry, tmp, msi_list, list) {
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		if (entry->msi_attrib.is_msix) {
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			if (list_is_last(&entry->list, msi_list))
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				iounmap(entry->mask_base);
		}
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		list_del(&entry->list);
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		free_msi_entry(entry);
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	}
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	if (dev->msi_irq_groups) {
		sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
		msi_attrs = dev->msi_irq_groups[0]->attrs;
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		while (msi_attrs[count]) {
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			dev_attr = container_of(msi_attrs[count],
						struct device_attribute, attr);
			kfree(dev_attr->attr.name);
			kfree(dev_attr);
			++count;
		}
		kfree(msi_attrs);
		kfree(dev->msi_irq_groups[0]);
		kfree(dev->msi_irq_groups);
		dev->msi_irq_groups = NULL;
	}
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}
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static void pci_intx_for_msi(struct pci_dev *dev, int enable)
{
	if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
		pci_intx(dev, enable);
}

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static void __pci_restore_msi_state(struct pci_dev *dev)
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{
	u16 control;
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	struct msi_desc *entry;
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	if (!dev->msi_enabled)
		return;

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	entry = irq_get_msi_desc(dev->irq);
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	pci_intx_for_msi(dev, 0);
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	pci_msi_set_enable(dev, 0);
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	arch_restore_msi_irqs(dev);
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	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
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	msi_mask_irq(entry, msi_mask(entry->msi_attrib.multi_cap),
		     entry->masked);
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	control &= ~PCI_MSI_FLAGS_QSIZE;
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	control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE;
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	pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
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}

static void __pci_restore_msix_state(struct pci_dev *dev)
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{
	struct msi_desc *entry;

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	if (!dev->msix_enabled)
		return;
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	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
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	/* route the table */
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	pci_intx_for_msi(dev, 0);
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	pci_msix_clear_and_set_ctrl(dev, 0,
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				PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL);
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	arch_restore_msi_irqs(dev);
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	for_each_pci_msi_entry(entry, dev)
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		msix_mask_irq(entry, entry->masked);
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	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
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}
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void pci_restore_msi_state(struct pci_dev *dev)
{
	__pci_restore_msi_state(dev);
	__pci_restore_msix_state(dev);
}
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EXPORT_SYMBOL_GPL(pci_restore_msi_state);
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438
static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
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			     char *buf)
{
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	struct msi_desc *entry;
	unsigned long irq;
	int retval;
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	retval = kstrtoul(attr->attr.name, 10, &irq);
	if (retval)
		return retval;
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	entry = irq_get_msi_desc(irq);
	if (entry)
		return sprintf(buf, "%s\n",
				entry->msi_attrib.is_msix ? "msix" : "msi");

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	return -ENODEV;
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}

static int populate_msi_sysfs(struct pci_dev *pdev)
{
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	struct attribute **msi_attrs;
	struct attribute *msi_attr;
	struct device_attribute *msi_dev_attr;
	struct attribute_group *msi_irq_group;
	const struct attribute_group **msi_irq_groups;
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	struct msi_desc *entry;
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	int ret = -ENOMEM;
	int num_msi = 0;
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	int count = 0;
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	int i;
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470
	/* Determine how many msi entries we have */
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	for_each_pci_msi_entry(entry, pdev)
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		num_msi += entry->nvec_used;
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	if (!num_msi)
		return 0;
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	/* Dynamically create the MSI attributes for the PCI device */
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	msi_attrs = kcalloc(num_msi + 1, sizeof(void *), GFP_KERNEL);
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	if (!msi_attrs)
		return -ENOMEM;
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	for_each_pci_msi_entry(entry, pdev) {
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		for (i = 0; i < entry->nvec_used; i++) {
			msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);
			if (!msi_dev_attr)
				goto error_attrs;
			msi_attrs[count] = &msi_dev_attr->attr;

			sysfs_attr_init(&msi_dev_attr->attr);
			msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",
							    entry->irq + i);
			if (!msi_dev_attr->attr.name)
				goto error_attrs;
			msi_dev_attr->attr.mode = S_IRUGO;
			msi_dev_attr->show = msi_mode_show;
			++count;
		}
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	}

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	msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL);
	if (!msi_irq_group)
		goto error_attrs;
	msi_irq_group->name = "msi_irqs";
	msi_irq_group->attrs = msi_attrs;

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	msi_irq_groups = kcalloc(2, sizeof(void *), GFP_KERNEL);
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	if (!msi_irq_groups)
		goto error_irq_group;
	msi_irq_groups[0] = msi_irq_group;

	ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups);
	if (ret)
		goto error_irq_groups;
	pdev->msi_irq_groups = msi_irq_groups;

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	return 0;

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error_irq_groups:
	kfree(msi_irq_groups);
error_irq_group:
	kfree(msi_irq_group);
error_attrs:
	count = 0;
	msi_attr = msi_attrs[count];
	while (msi_attr) {
		msi_dev_attr = container_of(msi_attr, struct device_attribute, attr);
		kfree(msi_attr->name);
		kfree(msi_dev_attr);
		++count;
		msi_attr = msi_attrs[count];
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	}
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	kfree(msi_attrs);
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	return ret;
}

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static struct msi_desc *
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msi_setup_entry(struct pci_dev *dev, int nvec, const struct irq_affinity *affd)
536
{
537
	struct cpumask *masks = NULL;
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	struct msi_desc *entry;
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	u16 control;

541
	if (affd)
542
		masks = irq_create_affinity_masks(nvec, affd);
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544 545

	/* MSI Entry Initialization */
546
	entry = alloc_msi_entry(&dev->dev, nvec, masks);
547
	if (!entry)
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		goto out;
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	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);

	entry->msi_attrib.is_msix	= 0;
	entry->msi_attrib.is_64		= !!(control & PCI_MSI_FLAGS_64BIT);
	entry->msi_attrib.entry_nr	= 0;
	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
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	entry->msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));
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	if (control & PCI_MSI_FLAGS_64BIT)
		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
	else
		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;

	/* Save the initial mask status */
	if (entry->msi_attrib.maskbit)
		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);

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out:
	kfree(masks);
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	return entry;
}

574 575 576 577
static int msi_verify_entries(struct pci_dev *dev)
{
	struct msi_desc *entry;

578
	for_each_pci_msi_entry(entry, dev) {
579 580
		if (!dev->no_64bit_msi || !entry->msg.address_hi)
			continue;
581
		pci_err(dev, "Device has broken 64-bit MSI but arch"
582 583 584 585 586 587
			" tried to assign one above 4G\n");
		return -EIO;
	}
	return 0;
}

L
Linus Torvalds 已提交
588 589 590
/**
 * msi_capability_init - configure device's MSI capability structure
 * @dev: pointer to the pci_dev data structure of MSI device function
591
 * @nvec: number of interrupts to allocate
592
 * @affd: description of automatic irq affinity assignments (may be %NULL)
L
Linus Torvalds 已提交
593
 *
594 595 596 597 598 599
 * Setup the MSI capability structure of the device with the requested
 * number of interrupts.  A return value of zero indicates the successful
 * setup of an entry with the new MSI irq.  A negative return value indicates
 * an error, and a positive return value indicates the number of interrupts
 * which could have been allocated.
 */
600 601
static int msi_capability_init(struct pci_dev *dev, int nvec,
			       const struct irq_affinity *affd)
L
Linus Torvalds 已提交
602 603
{
	struct msi_desc *entry;
604
	int ret;
605
	unsigned mask;
L
Linus Torvalds 已提交
606

607
	pci_msi_set_enable(dev, 0);	/* Disable MSI during set up */
608

609
	entry = msi_setup_entry(dev, nvec, affd);
610 611
	if (!entry)
		return -ENOMEM;
612

613
	/* All MSIs are unmasked by default, Mask them all */
614
	mask = msi_mask(entry->msi_attrib.multi_cap);
615 616
	msi_mask_irq(entry, mask, mask);

617
	list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
618

L
Linus Torvalds 已提交
619
	/* Configure MSI capability structure */
620
	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
621
	if (ret) {
622
		msi_mask_irq(entry, mask, ~mask);
623
		free_msi_irqs(dev);
624
		return ret;
625
	}
626

627 628 629 630 631 632 633
	ret = msi_verify_entries(dev);
	if (ret) {
		msi_mask_irq(entry, mask, ~mask);
		free_msi_irqs(dev);
		return ret;
	}

634 635 636 637 638 639 640
	ret = populate_msi_sysfs(dev);
	if (ret) {
		msi_mask_irq(entry, mask, ~mask);
		free_msi_irqs(dev);
		return ret;
	}

L
Linus Torvalds 已提交
641
	/* Set MSI enabled bits	 */
642
	pci_intx_for_msi(dev, 0);
643
	pci_msi_set_enable(dev, 1);
644
	dev->msi_enabled = 1;
L
Linus Torvalds 已提交
645

646
	pcibios_free_irq(dev);
647
	dev->irq = entry->irq;
L
Linus Torvalds 已提交
648 649 650
	return 0;
}

651
static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
652
{
653
	resource_size_t phys_addr;
654
	u32 table_offset;
655
	unsigned long flags;
656 657
	u8 bir;

658 659
	pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
			      &table_offset);
660
	bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
661 662 663 664
	flags = pci_resource_flags(dev, bir);
	if (!flags || (flags & IORESOURCE_UNSET))
		return NULL;

665
	table_offset &= PCI_MSIX_TABLE_OFFSET;
666 667 668 669 670
	phys_addr = pci_resource_start(dev, bir) + table_offset;

	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
}

671
static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,
672
			      struct msix_entry *entries, int nvec,
673
			      const struct irq_affinity *affd)
674
{
675
	struct cpumask *curmsk, *masks = NULL;
676
	struct msi_desc *entry;
677
	int ret, i;
678

679
	if (affd)
680
		masks = irq_create_affinity_masks(nvec, affd);
681

682 683
	for (i = 0, curmsk = masks; i < nvec; i++) {
		entry = alloc_msi_entry(&dev->dev, 1, curmsk);
684 685 686 687 688 689
		if (!entry) {
			if (!i)
				iounmap(base);
			else
				free_msi_irqs(dev);
			/* No enough memory. Don't try again */
690 691
			ret = -ENOMEM;
			goto out;
692 693 694 695
		}

		entry->msi_attrib.is_msix	= 1;
		entry->msi_attrib.is_64		= 1;
696 697 698 699
		if (entries)
			entry->msi_attrib.entry_nr = entries[i].entry;
		else
			entry->msi_attrib.entry_nr = i;
700 701 702
		entry->msi_attrib.default_irq	= dev->irq;
		entry->mask_base		= base;

703
		list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));
704 705
		if (masks)
			curmsk++;
706
	}
707 708 709
	ret = 0;
out:
	kfree(masks);
710
	return ret;
711 712
}

713
static void msix_program_entries(struct pci_dev *dev,
714
				 struct msix_entry *entries)
715 716 717 718
{
	struct msi_desc *entry;
	int i = 0;

719
	for_each_pci_msi_entry(entry, dev) {
720 721
		if (entries)
			entries[i++].vector = entry->irq;
722 723
		entry->masked = readl(pci_msix_desc_addr(entry) +
				PCI_MSIX_ENTRY_VECTOR_CTRL);
724 725 726 727
		msix_mask_irq(entry, 1);
	}
}

L
Linus Torvalds 已提交
728 729 730
/**
 * msix_capability_init - configure device's MSI-X capability
 * @dev: pointer to the pci_dev data structure of MSI-X device function
R
Randy Dunlap 已提交
731 732
 * @entries: pointer to an array of struct msix_entry entries
 * @nvec: number of @entries
733
 * @affd: Optional pointer to enable automatic affinity assignement
L
Linus Torvalds 已提交
734
 *
735
 * Setup the MSI-X capability structure of device function with a
736 737
 * single MSI-X irq. A return of zero indicates the successful setup of
 * requested MSI-X entries with allocated irqs or non-zero for otherwise.
L
Linus Torvalds 已提交
738
 **/
739
static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
740
				int nvec, const struct irq_affinity *affd)
L
Linus Torvalds 已提交
741
{
742
	int ret;
743
	u16 control;
L
Linus Torvalds 已提交
744 745
	void __iomem *base;

746
	/* Ensure MSI-X is disabled while it is set up */
747
	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
748

749
	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
L
Linus Torvalds 已提交
750
	/* Request & Map MSI-X table region */
751
	base = msix_map_region(dev, msix_table_size(control));
752
	if (!base)
L
Linus Torvalds 已提交
753 754
		return -ENOMEM;

755
	ret = msix_setup_entries(dev, base, entries, nvec, affd);
756 757
	if (ret)
		return ret;
758

759
	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
760
	if (ret)
761
		goto out_avail;
762

763 764 765 766 767
	/* Check if all MSI entries honor device restrictions */
	ret = msi_verify_entries(dev);
	if (ret)
		goto out_free;

768 769 770 771 772
	/*
	 * Some devices require MSI-X to be enabled before we can touch the
	 * MSI-X registers.  We need to mask all the vectors to prevent
	 * interrupts coming in before they're fully set up.
	 */
773
	pci_msix_clear_and_set_ctrl(dev, 0,
774
				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
775

776
	msix_program_entries(dev, entries);
777

778
	ret = populate_msi_sysfs(dev);
779 780
	if (ret)
		goto out_free;
781

782
	/* Set MSI-X enabled bits and unmask the function */
783
	pci_intx_for_msi(dev, 0);
784
	dev->msix_enabled = 1;
785
	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
786

787
	pcibios_free_irq(dev);
L
Linus Torvalds 已提交
788
	return 0;
789

790
out_avail:
791 792 793 794 795
	if (ret < 0) {
		/*
		 * If we had some success, report the number of irqs
		 * we succeeded in setting up.
		 */
796
		struct msi_desc *entry;
797 798
		int avail = 0;

799
		for_each_pci_msi_entry(entry, dev) {
800 801 802 803 804 805 806
			if (entry->irq != 0)
				avail++;
		}
		if (avail != 0)
			ret = avail;
	}

807
out_free:
808 809 810
	free_msi_irqs(dev);

	return ret;
L
Linus Torvalds 已提交
811 812
}

813
/**
814
 * pci_msi_supported - check whether MSI may be enabled on a device
815
 * @dev: pointer to the pci_dev data structure of MSI device function
816
 * @nvec: how many MSIs have been requested ?
817
 *
818
 * Look at global flags, the device itself, and its parent buses
819
 * to determine if MSI/-X are supported for the device. If MSI/-X is
820
 * supported return 1, else return 0.
821
 **/
822
static int pci_msi_supported(struct pci_dev *dev, int nvec)
823 824 825
{
	struct pci_bus *bus;

826
	/* MSI must be globally enabled and supported by the device */
827
	if (!pci_msi_enable)
828
		return 0;
829 830

	if (!dev || dev->no_msi || dev->current_state != PCI_D0)
831
		return 0;
832

833 834 835 836 837 838
	/*
	 * You can't ask to have 0 or less MSIs configured.
	 *  a) it's stupid ..
	 *  b) the list manipulation code assumes nvec >= 1.
	 */
	if (nvec < 1)
839
		return 0;
840

H
Hidetoshi Seto 已提交
841 842 843
	/*
	 * Any bridge which does NOT route MSI transactions from its
	 * secondary bus to its primary bus must set NO_MSI flag on
844 845 846 847
	 * the secondary pci_bus.
	 * We expect only arch-specific PCI host bus controller driver
	 * or quirks for specific PCI bridges to be setting NO_MSI.
	 */
848 849
	for (bus = dev->bus; bus; bus = bus->parent)
		if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
850
			return 0;
851

852
	return 1;
853 854
}

855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
/**
 * pci_msi_vec_count - Return the number of MSI vectors a device can send
 * @dev: device to report about
 *
 * This function returns the number of MSI vectors a device requested via
 * Multiple Message Capable register. It returns a negative errno if the
 * device is not capable sending MSI interrupts. Otherwise, the call succeeds
 * and returns a power of two, up to a maximum of 2^5 (32), according to the
 * MSI specification.
 **/
int pci_msi_vec_count(struct pci_dev *dev)
{
	int ret;
	u16 msgctl;

	if (!dev->msi_cap)
		return -EINVAL;

	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl);
	ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);

	return ret;
}
EXPORT_SYMBOL(pci_msi_vec_count);

880
static void pci_msi_shutdown(struct pci_dev *dev)
L
Linus Torvalds 已提交
881
{
882 883
	struct msi_desc *desc;
	u32 mask;
L
Linus Torvalds 已提交
884

885
	if (!pci_msi_enable || !dev || !dev->msi_enabled)
E
Eric W. Biederman 已提交
886 887
		return;

888
	BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
889
	desc = first_pci_msi_entry(dev);
890

891
	pci_msi_set_enable(dev, 0);
892
	pci_intx_for_msi(dev, 1);
893
	dev->msi_enabled = 0;
894

895
	/* Return the device with MSI unmasked as initial states */
896
	mask = msi_mask(desc->msi_attrib.multi_cap);
897
	/* Keep cached state to be restored */
898
	__pci_msi_desc_mask_irq(desc, mask, ~mask);
899 900

	/* Restore dev->irq to its default pin-assertion irq */
901
	dev->irq = desc->msi_attrib.default_irq;
902
	pcibios_alloc_irq(dev);
903
}
904

H
Hidetoshi Seto 已提交
905
void pci_disable_msi(struct pci_dev *dev)
906 907 908 909 910
{
	if (!pci_msi_enable || !dev || !dev->msi_enabled)
		return;

	pci_msi_shutdown(dev);
911
	free_msi_irqs(dev);
L
Linus Torvalds 已提交
912
}
913
EXPORT_SYMBOL(pci_disable_msi);
L
Linus Torvalds 已提交
914

915
/**
916
 * pci_msix_vec_count - return the number of device's MSI-X table entries
917
 * @dev: pointer to the pci_dev data structure of MSI-X device function
918 919 920 921 922 923
 * This function returns the number of device's MSI-X table entries and
 * therefore the number of MSI-X vectors device is capable of sending.
 * It returns a negative errno if the device is not capable of sending MSI-X
 * interrupts.
 **/
int pci_msix_vec_count(struct pci_dev *dev)
924 925 926
{
	u16 control;

927
	if (!dev->msix_cap)
928
		return -EINVAL;
929

930
	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
931
	return msix_table_size(control);
932
}
933
EXPORT_SYMBOL(pci_msix_vec_count);
934

935
static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
936
			     int nvec, const struct irq_affinity *affd)
L
Linus Torvalds 已提交
937
{
938
	int nr_entries;
E
Eric W. Biederman 已提交
939
	int i, j;
L
Linus Torvalds 已提交
940

941 942
	if (!pci_msi_supported(dev, nvec))
		return -EINVAL;
943

944 945 946
	nr_entries = pci_msix_vec_count(dev);
	if (nr_entries < 0)
		return nr_entries;
L
Linus Torvalds 已提交
947
	if (nvec > nr_entries)
948
		return nr_entries;
L
Linus Torvalds 已提交
949

950 951 952 953 954 955 956 957 958
	if (entries) {
		/* Check for any invalid entries */
		for (i = 0; i < nvec; i++) {
			if (entries[i].entry >= nr_entries)
				return -EINVAL;		/* invalid entry */
			for (j = i + 1; j < nvec; j++) {
				if (entries[i].entry == entries[j].entry)
					return -EINVAL;	/* duplicate entry */
			}
L
Linus Torvalds 已提交
959 960
		}
	}
961

962
	/* Check whether driver already requested for MSI irq */
H
Hidetoshi Seto 已提交
963
	if (dev->msi_enabled) {
964
		pci_info(dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
L
Linus Torvalds 已提交
965 966
		return -EINVAL;
	}
967
	return msix_capability_init(dev, entries, nvec, affd);
968 969
}

970
static void pci_msix_shutdown(struct pci_dev *dev)
971
{
972 973
	struct msi_desc *entry;

974
	if (!pci_msi_enable || !dev || !dev->msix_enabled)
E
Eric W. Biederman 已提交
975 976
		return;

977 978 979 980 981
	if (pci_dev_is_disconnected(dev)) {
		dev->msix_enabled = 0;
		return;
	}

982
	/* Return the device with MSI-X masked as initial states */
983
	for_each_pci_msi_entry(entry, dev) {
984
		/* Keep cached states to be restored */
985
		__pci_msix_desc_mask_irq(entry, 1);
986 987
	}

988
	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
989
	pci_intx_for_msi(dev, 1);
990
	dev->msix_enabled = 0;
991
	pcibios_alloc_irq(dev);
992
}
993

H
Hidetoshi Seto 已提交
994
void pci_disable_msix(struct pci_dev *dev)
995 996 997 998 999
{
	if (!pci_msi_enable || !dev || !dev->msix_enabled)
		return;

	pci_msix_shutdown(dev);
1000
	free_msi_irqs(dev);
L
Linus Torvalds 已提交
1001
}
1002
EXPORT_SYMBOL(pci_disable_msix);
L
Linus Torvalds 已提交
1003

1004 1005 1006 1007
void pci_no_msi(void)
{
	pci_msi_enable = 0;
}
1008

1009 1010 1011 1012 1013 1014 1015
/**
 * pci_msi_enabled - is MSI enabled?
 *
 * Returns true if MSI has not been disabled by the command-line option
 * pci=nomsi.
 **/
int pci_msi_enabled(void)
1016
{
1017
	return pci_msi_enable;
1018
}
1019
EXPORT_SYMBOL(pci_msi_enabled);
1020

1021
static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
1022
				  const struct irq_affinity *affd)
1023
{
1024
	int nvec;
1025 1026
	int rc;

1027 1028
	if (!pci_msi_supported(dev, minvec))
		return -EINVAL;
1029 1030 1031

	/* Check whether driver already requested MSI-X irqs */
	if (dev->msix_enabled) {
1032
		pci_info(dev, "can't enable MSI (MSI-X already enabled)\n");
1033 1034 1035
		return -EINVAL;
	}

1036 1037 1038
	if (maxvec < minvec)
		return -ERANGE;

1039 1040 1041 1042 1043 1044 1045
	/*
	 * If the caller is passing in sets, we can't support a range of
	 * vectors. The caller needs to handle that.
	 */
	if (affd && affd->nr_sets && minvec != maxvec)
		return -EINVAL;

1046 1047 1048
	if (WARN_ON_ONCE(dev->msi_enabled))
		return -EINVAL;

1049 1050 1051
	nvec = pci_msi_vec_count(dev);
	if (nvec < 0)
		return nvec;
1052
	if (nvec < minvec)
1053
		return -ENOSPC;
1054 1055

	if (nvec > maxvec)
1056 1057
		nvec = maxvec;

1058
	for (;;) {
1059
		if (affd) {
1060
			nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
1061 1062 1063 1064
			if (nvec < minvec)
				return -ENOSPC;
		}

1065
		rc = msi_capability_init(dev, nvec, affd);
1066 1067 1068 1069
		if (rc == 0)
			return nvec;

		if (rc < 0)
1070
			return rc;
1071 1072 1073 1074 1075 1076 1077
		if (rc < minvec)
			return -ENOSPC;

		nvec = rc;
	}
}

1078 1079
/* deprecated, don't use */
int pci_enable_msi(struct pci_dev *dev)
1080
{
1081 1082 1083 1084
	int rc = __pci_enable_msi_range(dev, 1, 1, NULL);
	if (rc < 0)
		return rc;
	return 0;
1085
}
1086
EXPORT_SYMBOL(pci_enable_msi);
1087 1088

static int __pci_enable_msix_range(struct pci_dev *dev,
1089 1090
				   struct msix_entry *entries, int minvec,
				   int maxvec, const struct irq_affinity *affd)
1091
{
1092
	int rc, nvec = maxvec;
1093 1094 1095 1096

	if (maxvec < minvec)
		return -ERANGE;

1097 1098 1099 1100 1101 1102 1103
	/*
	 * If the caller is passing in sets, we can't support a range of
	 * supported vectors. The caller needs to handle that.
	 */
	if (affd && affd->nr_sets && minvec != maxvec)
		return -EINVAL;

1104 1105 1106
	if (WARN_ON_ONCE(dev->msix_enabled))
		return -EINVAL;

1107
	for (;;) {
1108
		if (affd) {
1109
			nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
1110
			if (nvec < minvec)
1111 1112 1113
				return -ENOSPC;
		}

1114
		rc = __pci_enable_msix(dev, entries, nvec, affd);
1115 1116 1117 1118 1119 1120 1121 1122 1123 1124
		if (rc == 0)
			return nvec;

		if (rc < 0)
			return rc;
		if (rc < minvec)
			return -ENOSPC;

		nvec = rc;
	}
1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
}

/**
 * pci_enable_msix_range - configure device's MSI-X capability structure
 * @dev: pointer to the pci_dev data structure of MSI-X device function
 * @entries: pointer to an array of MSI-X entries
 * @minvec: minimum number of MSI-X irqs requested
 * @maxvec: maximum number of MSI-X irqs requested
 *
 * Setup the MSI-X capability structure of device function with a maximum
 * possible number of interrupts in the range between @minvec and @maxvec
 * upon its software driver call to request for MSI-X mode enabled on its
 * hardware device function. It returns a negative errno if an error occurs.
 * If it succeeds, it returns the actual number of interrupts allocated and
 * indicates the successful configuration of MSI-X capability structure
 * with new allocated MSI-X interrupts.
 **/
int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
1143
		int minvec, int maxvec)
1144
{
1145
	return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL);
1146 1147
}
EXPORT_SYMBOL(pci_enable_msix_range);
1148

1149
/**
1150
 * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
1151 1152 1153 1154
 * @dev:		PCI device to operate on
 * @min_vecs:		minimum number of vectors required (must be >= 1)
 * @max_vecs:		maximum (desired) number of vectors
 * @flags:		flags or quirks for the allocation
1155
 * @affd:		optional description of the affinity requirements
1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166
 *
 * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
 * vectors if available, and fall back to a single legacy vector
 * if neither is available.  Return the number of vectors allocated,
 * (which might be smaller than @max_vecs) if successful, or a negative
 * error code on error. If less than @min_vecs interrupt vectors are
 * available for @dev the function will fail with -ENOSPC.
 *
 * To get the Linux IRQ number used for a vector that can be passed to
 * request_irq() use the pci_irq_vector() helper.
 */
1167 1168 1169
int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
				   unsigned int max_vecs, unsigned int flags,
				   const struct irq_affinity *affd)
1170
{
1171
	static const struct irq_affinity msi_default_affd;
1172 1173
	int msix_vecs = -ENOSPC;
	int msi_vecs = -ENOSPC;
1174

1175 1176 1177 1178 1179 1180 1181
	if (flags & PCI_IRQ_AFFINITY) {
		if (!affd)
			affd = &msi_default_affd;
	} else {
		if (WARN_ON(affd))
			affd = NULL;
	}
1182

1183
	if (flags & PCI_IRQ_MSIX) {
1184 1185 1186 1187
		msix_vecs = __pci_enable_msix_range(dev, NULL, min_vecs,
						    max_vecs, affd);
		if (msix_vecs > 0)
			return msix_vecs;
1188 1189
	}

1190
	if (flags & PCI_IRQ_MSI) {
1191 1192 1193 1194
		msi_vecs = __pci_enable_msi_range(dev, min_vecs, max_vecs,
						  affd);
		if (msi_vecs > 0)
			return msi_vecs;
1195 1196 1197
	}

	/* use legacy irq if allowed */
1198 1199 1200 1201 1202
	if (flags & PCI_IRQ_LEGACY) {
		if (min_vecs == 1 && dev->irq) {
			pci_intx(dev, 1);
			return 1;
		}
1203 1204
	}

1205 1206 1207
	if (msix_vecs == -ENOSPC)
		return -ENOSPC;
	return msi_vecs;
1208
}
1209
EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity);
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/**
 * pci_free_irq_vectors - free previously allocated IRQs for a device
 * @dev:		PCI device to operate on
 *
 * Undoes the allocations and enabling in pci_alloc_irq_vectors().
 */
void pci_free_irq_vectors(struct pci_dev *dev)
{
	pci_disable_msix(dev);
	pci_disable_msi(dev);
}
EXPORT_SYMBOL(pci_free_irq_vectors);

/**
 * pci_irq_vector - return Linux IRQ number of a device vector
 * @dev: PCI device to operate on
 * @nr: device-relative interrupt vector index (0-based).
 */
int pci_irq_vector(struct pci_dev *dev, unsigned int nr)
{
	if (dev->msix_enabled) {
		struct msi_desc *entry;
		int i = 0;

		for_each_pci_msi_entry(entry, dev) {
			if (i == nr)
				return entry->irq;
			i++;
		}
		WARN_ON_ONCE(1);
		return -EINVAL;
	}

	if (dev->msi_enabled) {
		struct msi_desc *entry = first_pci_msi_entry(dev);

		if (WARN_ON_ONCE(nr >= entry->nvec_used))
			return -EINVAL;
	} else {
		if (WARN_ON_ONCE(nr > 0))
			return -EINVAL;
	}

	return dev->irq + nr;
}
EXPORT_SYMBOL(pci_irq_vector);

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/**
 * pci_irq_get_affinity - return the affinity of a particular msi vector
 * @dev:	PCI device to operate on
 * @nr:		device-relative interrupt vector index (0-based).
 */
const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
{
	if (dev->msix_enabled) {
		struct msi_desc *entry;
		int i = 0;

		for_each_pci_msi_entry(entry, dev) {
			if (i == nr)
				return entry->affinity;
			i++;
		}
		WARN_ON_ONCE(1);
		return NULL;
	} else if (dev->msi_enabled) {
		struct msi_desc *entry = first_pci_msi_entry(dev);

1279 1280
		if (WARN_ON_ONCE(!entry || !entry->affinity ||
				 nr >= entry->nvec_used))
1281 1282 1283 1284 1285 1286 1287 1288 1289
			return NULL;

		return &entry->affinity[nr];
	} else {
		return cpu_possible_mask;
	}
}
EXPORT_SYMBOL(pci_irq_get_affinity);

1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305
/**
 * pci_irq_get_node - return the numa node of a particular msi vector
 * @pdev:	PCI device to operate on
 * @vec:	device-relative interrupt vector index (0-based).
 */
int pci_irq_get_node(struct pci_dev *pdev, int vec)
{
	const struct cpumask *mask;

	mask = pci_irq_get_affinity(pdev, vec);
	if (mask)
		return local_memory_node(cpu_to_node(cpumask_first(mask)));
	return dev_to_node(&pdev->dev);
}
EXPORT_SYMBOL(pci_irq_get_node);

1306 1307 1308 1309
struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc)
{
	return to_pci_dev(desc->dev);
}
1310
EXPORT_SYMBOL(msi_desc_to_pci_dev);
1311

1312 1313 1314 1315 1316 1317 1318 1319
void *msi_desc_to_pci_sysdata(struct msi_desc *desc)
{
	struct pci_dev *dev = msi_desc_to_pci_dev(desc);

	return dev->bus->sysdata;
}
EXPORT_SYMBOL_GPL(msi_desc_to_pci_sysdata);

1320 1321 1322 1323 1324 1325 1326 1327
#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
/**
 * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
 * @irq_data:	Pointer to interrupt data of the MSI interrupt
 * @msg:	Pointer to the message
 */
void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
{
1328
	struct msi_desc *desc = irq_data_get_msi_desc(irq_data);
1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373

	/*
	 * For MSI-X desc->irq is always equal to irq_data->irq. For
	 * MSI only the first interrupt of MULTI MSI passes the test.
	 */
	if (desc->irq == irq_data->irq)
		__pci_write_msi_msg(desc, msg);
}

/**
 * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
 * @dev:	Pointer to the PCI device
 * @desc:	Pointer to the msi descriptor
 *
 * The ID number is only used within the irqdomain.
 */
irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
					  struct msi_desc *desc)
{
	return (irq_hw_number_t)desc->msi_attrib.entry_nr |
		PCI_DEVID(dev->bus->number, dev->devfn) << 11 |
		(pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27;
}

static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
{
	return !desc->msi_attrib.is_msix && desc->nvec_used > 1;
}

/**
 * pci_msi_domain_check_cap - Verify that @domain supports the capabilities for @dev
 * @domain:	The interrupt domain to check
 * @info:	The domain info for verification
 * @dev:	The device to check
 *
 * Returns:
 *  0 if the functionality is supported
 *  1 if Multi MSI is requested, but the domain does not support it
 *  -ENOTSUPP otherwise
 */
int pci_msi_domain_check_cap(struct irq_domain *domain,
			     struct msi_domain_info *info, struct device *dev)
{
	struct msi_desc *desc = first_pci_msi_entry(to_pci_dev(dev));

1374
	/* Special handling to support __pci_enable_msi_range() */
1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386
	if (pci_msi_desc_is_multi_msi(desc) &&
	    !(info->flags & MSI_FLAG_MULTI_PCI_MSI))
		return 1;
	else if (desc->msi_attrib.is_msix && !(info->flags & MSI_FLAG_PCI_MSIX))
		return -ENOTSUPP;

	return 0;
}

static int pci_msi_domain_handle_error(struct irq_domain *domain,
				       struct msi_desc *desc, int error)
{
1387
	/* Special handling to support __pci_enable_msi_range() */
1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434
	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
		return 1;

	return error;
}

#ifdef GENERIC_MSI_DOMAIN_OPS
static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
				    struct msi_desc *desc)
{
	arg->desc = desc;
	arg->hwirq = pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc),
					       desc);
}
#else
#define pci_msi_domain_set_desc		NULL
#endif

static struct msi_domain_ops pci_msi_domain_ops_default = {
	.set_desc	= pci_msi_domain_set_desc,
	.msi_check	= pci_msi_domain_check_cap,
	.handle_error	= pci_msi_domain_handle_error,
};

static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
{
	struct msi_domain_ops *ops = info->ops;

	if (ops == NULL) {
		info->ops = &pci_msi_domain_ops_default;
	} else {
		if (ops->set_desc == NULL)
			ops->set_desc = pci_msi_domain_set_desc;
		if (ops->msi_check == NULL)
			ops->msi_check = pci_msi_domain_check_cap;
		if (ops->handle_error == NULL)
			ops->handle_error = pci_msi_domain_handle_error;
	}
}

static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
{
	struct irq_chip *chip = info->chip;

	BUG_ON(!chip);
	if (!chip->irq_write_msi_msg)
		chip->irq_write_msi_msg = pci_msi_domain_write_msg;
1435 1436 1437 1438
	if (!chip->irq_mask)
		chip->irq_mask = pci_msi_mask_irq;
	if (!chip->irq_unmask)
		chip->irq_unmask = pci_msi_unmask_irq;
1439 1440 1441
}

/**
1442 1443
 * pci_msi_create_irq_domain - Create a MSI interrupt domain
 * @fwnode:	Optional fwnode of the interrupt controller
1444 1445 1446 1447 1448 1449 1450 1451
 * @info:	MSI domain info
 * @parent:	Parent irq domain
 *
 * Updates the domain and chip ops and creates a MSI interrupt domain.
 *
 * Returns:
 * A domain pointer or NULL in case of failure.
 */
1452
struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
1453 1454 1455
					     struct msi_domain_info *info,
					     struct irq_domain *parent)
{
1456 1457
	struct irq_domain *domain;

1458 1459 1460
	if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE))
		info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;

1461 1462 1463 1464 1465
	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
		pci_msi_domain_update_dom_ops(info);
	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
		pci_msi_domain_update_chip_ops(info);

1466
	info->flags |= MSI_FLAG_ACTIVATE_EARLY;
1467 1468
	if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
		info->flags |= MSI_FLAG_MUST_REACTIVATE;
1469

1470 1471 1472
	/* PCI-MSI is oneshot-safe */
	info->chip->flags |= IRQCHIP_ONESHOT_SAFE;

1473
	domain = msi_create_irq_domain(fwnode, info, parent);
1474 1475 1476
	if (!domain)
		return NULL;

1477
	irq_domain_update_bus_token(domain, DOMAIN_BUS_PCI_MSI);
1478
	return domain;
1479
}
1480
EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain);
1481

1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494
/*
 * Users of the generic MSI infrastructure expect a device to have a single ID,
 * so with DMA aliases we have to pick the least-worst compromise. Devices with
 * DMA phantom functions tend to still emit MSIs from the real function number,
 * so we ignore those and only consider topological aliases where either the
 * alias device or RID appears on a different bus number. We also make the
 * reasonable assumption that bridges are walked in an upstream direction (so
 * the last one seen wins), and the much braver assumption that the most likely
 * case is that of PCI->PCIe so we should always use the alias RID. This echoes
 * the logic from intel_irq_remapping's set_msi_sid(), which presumably works
 * well enough in practice; in the face of the horrible PCIe<->PCI-X conditions
 * for taking ownership all we can really do is close our eyes and hope...
 */
1495 1496 1497
static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
{
	u32 *pa = data;
1498 1499 1500 1501
	u8 bus = PCI_BUS_NUM(*pa);

	if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus)
		*pa = alias;
1502 1503 1504

	return 0;
}
1505

1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518
/**
 * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
 * @domain:	The interrupt domain
 * @pdev:	The PCI device.
 *
 * The RID for a device is formed from the alias, with a firmware
 * supplied mapping applied
 *
 * Returns: The RID.
 */
u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
{
	struct device_node *of_node;
1519
	u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn);
1520 1521 1522 1523

	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);

	of_node = irq_domain_get_of_node(domain);
1524 1525
	rid = of_node ? of_msi_map_rid(&pdev->dev, of_node, rid) :
			iort_msi_map_rid(&pdev->dev, rid);
1526 1527 1528

	return rid;
}
1529 1530 1531 1532 1533 1534

/**
 * pci_msi_get_device_domain - Get the MSI domain for a given PCI device
 * @pdev:	The PCI device
 *
 * Use the firmware data to find a device-specific MSI domain
1535
 * (i.e. not one that is set as a default).
1536
 *
1537
 * Returns: The corresponding MSI domain or NULL if none has been found.
1538 1539 1540
 */
struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
{
1541
	struct irq_domain *dom;
1542
	u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn);
1543 1544

	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
1545 1546 1547 1548
	dom = of_msi_map_get_device_domain(&pdev->dev, rid);
	if (!dom)
		dom = iort_get_device_domain(&pdev->dev, rid);
	return dom;
1549
}
1550
#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */