The following commit has been merged into the irq/msi branch of tip: Commit-ID: 288c81ce4be7c15544605594966faaeb8803b5da Gitweb: https://git.kernel.org/tip/288c81ce4be7c15544605594966faaeb8803b5da Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Mon, 06 Dec 2021 23:27:47 +01:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Thu, 09 Dec 2021 11:52:22 +01:00 PCI/MSI: Move code into a separate directory msi.c is getting larger and really could do with a splitup. Move it into its own directory to prepare for that. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Tested-by: Juergen Gross <jgross@xxxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Link: https://lore.kernel.org/r/20211206210224.655043033@xxxxxxxxxxxxx --- Documentation/driver-api/pci/pci.rst | 2 +- drivers/pci/Makefile | 3 +- drivers/pci/msi.c | 1532 +------------------------- drivers/pci/msi/Makefile | 4 +- drivers/pci/msi/msi.c | 1532 +++++++++++++++++++++++++- 5 files changed, 1539 insertions(+), 1534 deletions(-) delete mode 100644 drivers/pci/msi.c create mode 100644 drivers/pci/msi/Makefile create mode 100644 drivers/pci/msi/msi.c diff --git a/Documentation/driver-api/pci/pci.rst b/Documentation/driver-api/pci/pci.rst index ca85e5e..4843cfa 100644 --- a/Documentation/driver-api/pci/pci.rst +++ b/Documentation/driver-api/pci/pci.rst @@ -13,7 +13,7 @@ PCI Support Library .. kernel-doc:: drivers/pci/search.c :export: -.. kernel-doc:: drivers/pci/msi.c +.. kernel-doc:: drivers/pci/msi/msi.c :export: .. kernel-doc:: drivers/pci/bus.c diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile index d62c4ac..37be95a 100644 --- a/drivers/pci/Makefile +++ b/drivers/pci/Makefile @@ -5,8 +5,9 @@ obj-$(CONFIG_PCI) += access.o bus.o probe.o host-bridge.o \ remove.o pci.o pci-driver.o search.o \ pci-sysfs.o rom.o setup-res.o irq.o vpd.o \ - setup-bus.o vc.o mmap.o setup-irq.o msi.o + setup-bus.o vc.o mmap.o setup-irq.o +obj-$(CONFIG_PCI) += msi/ obj-$(CONFIG_PCI) += pcie/ ifdef CONFIG_PCI diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c deleted file mode 100644 index 1573091..0000000 --- a/drivers/pci/msi.c +++ /dev/null @@ -1,1532 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * PCI Message Signaled Interrupt (MSI) - * - * Copyright (C) 2003-2004 Intel - * Copyright (C) Tom Long Nguyen (tom.l.nguyen@xxxxxxxxx) - * Copyright (C) 2016 Christoph Hellwig. - */ - -#include <linux/acpi_iort.h> -#include <linux/err.h> -#include <linux/export.h> -#include <linux/irq.h> -#include <linux/irqdomain.h> -#include <linux/msi.h> -#include <linux/of_irq.h> -#include <linux/pci.h> - -#include "pci.h" - -#ifdef CONFIG_PCI_MSI - -static int pci_msi_enable = 1; -int pci_msi_ignore_mask; - -#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) - -#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; - - domain = dev_get_msi_domain(&dev->dev); - if (domain && irq_domain_is_hierarchy(domain)) - return msi_domain_alloc_irqs(domain, &dev->dev, nvec); - - return arch_setup_msi_irqs(dev, nvec, type); -} - -static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) -{ - struct irq_domain *domain; - - domain = dev_get_msi_domain(&dev->dev); - if (domain && irq_domain_is_hierarchy(domain)) - msi_domain_free_irqs(domain, &dev->dev); - 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 - -#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS -/* Arch hooks */ -int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) -{ - return -EINVAL; -} - -void __weak arch_teardown_msi_irq(unsigned int irq) -{ -} - -int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) -{ - struct msi_desc *entry; - int ret; - - /* - * 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; - - for_each_pci_msi_entry(entry, dev) { - ret = arch_setup_msi_irq(dev, entry); - if (ret < 0) - return ret; - if (ret > 0) - return -ENOSPC; - } - - return 0; -} - -void __weak arch_teardown_msi_irqs(struct pci_dev *dev) -{ - int i; - struct msi_desc *entry; - - for_each_pci_msi_entry(entry, dev) - if (entry->irq) - for (i = 0; i < entry->nvec_used; i++) - arch_teardown_msi_irq(entry->irq + i); -} -#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */ - -/* - * 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. - */ -static inline __attribute_const__ u32 msi_multi_mask(struct msi_desc *desc) -{ - /* Don't shift by >= width of type */ - if (desc->pci.msi_attrib.multi_cap >= 5) - return 0xffffffff; - return (1 << (1 << desc->pci.msi_attrib.multi_cap)) - 1; -} - -static noinline void pci_msi_update_mask(struct msi_desc *desc, u32 clear, u32 set) -{ - raw_spinlock_t *lock = &desc->dev->msi_lock; - unsigned long flags; - - if (!desc->pci.msi_attrib.can_mask) - return; - - raw_spin_lock_irqsave(lock, flags); - desc->pci.msi_mask &= ~clear; - desc->pci.msi_mask |= set; - pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->pci.mask_pos, - desc->pci.msi_mask); - raw_spin_unlock_irqrestore(lock, flags); -} - -static inline void pci_msi_mask(struct msi_desc *desc, u32 mask) -{ - pci_msi_update_mask(desc, 0, mask); -} - -static inline void pci_msi_unmask(struct msi_desc *desc, u32 mask) -{ - pci_msi_update_mask(desc, mask, 0); -} - -static inline void __iomem *pci_msix_desc_addr(struct msi_desc *desc) -{ - return desc->pci.mask_base + desc->pci.msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; -} - -/* - * 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. - * It does not affect the msi_desc::msix_ctrl cache either. Use with care! - */ -static void pci_msix_write_vector_ctrl(struct msi_desc *desc, u32 ctrl) -{ - void __iomem *desc_addr = pci_msix_desc_addr(desc); - - if (desc->pci.msi_attrib.can_mask) - writel(ctrl, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL); -} - -static inline void pci_msix_mask(struct msi_desc *desc) -{ - desc->pci.msix_ctrl |= PCI_MSIX_ENTRY_CTRL_MASKBIT; - pci_msix_write_vector_ctrl(desc, desc->pci.msix_ctrl); - /* Flush write to device */ - readl(desc->pci.mask_base); -} - -static inline void pci_msix_unmask(struct msi_desc *desc) -{ - desc->pci.msix_ctrl &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; - pci_msix_write_vector_ctrl(desc, desc->pci.msix_ctrl); -} - -static void __pci_msi_mask_desc(struct msi_desc *desc, u32 mask) -{ - if (desc->pci.msi_attrib.is_msix) - pci_msix_mask(desc); - else - pci_msi_mask(desc, mask); -} - -static void __pci_msi_unmask_desc(struct msi_desc *desc, u32 mask) -{ - if (desc->pci.msi_attrib.is_msix) - pci_msix_unmask(desc); - else - pci_msi_unmask(desc, mask); -} - -/** - * 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) -{ - struct msi_desc *desc = irq_data_get_msi_desc(data); - - __pci_msi_mask_desc(desc, BIT(data->irq - desc->irq)); -} -EXPORT_SYMBOL_GPL(pci_msi_mask_irq); - -/** - * 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) -{ - struct msi_desc *desc = irq_data_get_msi_desc(data); - - __pci_msi_unmask_desc(desc, BIT(data->irq - desc->irq)); -} -EXPORT_SYMBOL_GPL(pci_msi_unmask_irq); - -void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg) -{ - struct pci_dev *dev = msi_desc_to_pci_dev(entry); - - BUG_ON(dev->current_state != PCI_D0); - - if (entry->pci.msi_attrib.is_msix) { - void __iomem *base = pci_msix_desc_addr(entry); - - if (WARN_ON_ONCE(entry->pci.msi_attrib.is_virtual)) - return; - - 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 { - int pos = dev->msi_cap; - u16 data; - - pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, - &msg->address_lo); - if (entry->pci.msi_attrib.is_64) { - pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, - &msg->address_hi); - pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data); - } else { - msg->address_hi = 0; - pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data); - } - msg->data = data; - } -} - -void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg) -{ - struct pci_dev *dev = msi_desc_to_pci_dev(entry); - - if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) { - /* Don't touch the hardware now */ - } else if (entry->pci.msi_attrib.is_msix) { - void __iomem *base = pci_msix_desc_addr(entry); - u32 ctrl = entry->pci.msix_ctrl; - bool unmasked = !(ctrl & PCI_MSIX_ENTRY_CTRL_MASKBIT); - - if (entry->pci.msi_attrib.is_virtual) - goto skip; - - /* - * The specification mandates that the entry is masked - * when the message is modified: - * - * "If software changes the Address or Data value of an - * entry while the entry is unmasked, the result is - * undefined." - */ - if (unmasked) - pci_msix_write_vector_ctrl(entry, ctrl | PCI_MSIX_ENTRY_CTRL_MASKBIT); - - 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); - - if (unmasked) - pci_msix_write_vector_ctrl(entry, ctrl); - - /* Ensure that the writes are visible in the device */ - readl(base + PCI_MSIX_ENTRY_DATA); - } else { - int pos = dev->msi_cap; - u16 msgctl; - - pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); - msgctl &= ~PCI_MSI_FLAGS_QSIZE; - msgctl |= entry->pci.msi_attrib.multiple << 4; - pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl); - - pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, - msg->address_lo); - if (entry->pci.msi_attrib.is_64) { - pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, - msg->address_hi); - pci_write_config_word(dev, pos + PCI_MSI_DATA_64, - msg->data); - } else { - pci_write_config_word(dev, pos + PCI_MSI_DATA_32, - msg->data); - } - /* Ensure that the writes are visible in the device */ - pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); - } - -skip: - entry->msg = *msg; - - if (entry->write_msi_msg) - entry->write_msi_msg(entry, entry->write_msi_msg_data); - -} - -void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg) -{ - struct msi_desc *entry = irq_get_msi_desc(irq); - - __pci_write_msi_msg(entry, msg); -} -EXPORT_SYMBOL_GPL(pci_write_msi_msg); - -static void free_msi_irqs(struct pci_dev *dev) -{ - struct list_head *msi_list = dev_to_msi_list(&dev->dev); - struct msi_desc *entry, *tmp; - int i; - - for_each_pci_msi_entry(entry, dev) - if (entry->irq) - for (i = 0; i < entry->nvec_used; i++) - BUG_ON(irq_has_action(entry->irq + i)); - - if (dev->msi_irq_groups) { - msi_destroy_sysfs(&dev->dev, dev->msi_irq_groups); - dev->msi_irq_groups = NULL; - } - - pci_msi_teardown_msi_irqs(dev); - - list_for_each_entry_safe(entry, tmp, msi_list, list) { - if (entry->pci.msi_attrib.is_msix) { - if (list_is_last(&entry->list, msi_list)) - iounmap(entry->pci.mask_base); - } - - list_del(&entry->list); - free_msi_entry(entry); - } -} - -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); -} - -static void pci_msi_set_enable(struct pci_dev *dev, int enable) -{ - u16 control; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - control &= ~PCI_MSI_FLAGS_ENABLE; - if (enable) - control |= PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); -} - -/* - * Architecture override returns true when the PCI MSI message should be - * written by the generic restore function. - */ -bool __weak arch_restore_msi_irqs(struct pci_dev *dev) -{ - return true; -} - -static void __pci_restore_msi_state(struct pci_dev *dev) -{ - struct msi_desc *entry; - u16 control; - - if (!dev->msi_enabled) - return; - - entry = irq_get_msi_desc(dev->irq); - - pci_intx_for_msi(dev, 0); - pci_msi_set_enable(dev, 0); - if (arch_restore_msi_irqs(dev)) - __pci_write_msi_msg(entry, &entry->msg); - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - pci_msi_update_mask(entry, 0, 0); - control &= ~PCI_MSI_FLAGS_QSIZE; - control |= (entry->pci.msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); -} - -static void pci_msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set) -{ - u16 ctrl; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl); - ctrl &= ~clear; - ctrl |= set; - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl); -} - -static void __pci_restore_msix_state(struct pci_dev *dev) -{ - struct msi_desc *entry; - bool write_msg; - - if (!dev->msix_enabled) - return; - BUG_ON(list_empty(dev_to_msi_list(&dev->dev))); - - /* route the table */ - pci_intx_for_msi(dev, 0); - pci_msix_clear_and_set_ctrl(dev, 0, - PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL); - - write_msg = arch_restore_msi_irqs(dev); - - for_each_pci_msi_entry(entry, dev) { - if (write_msg) - __pci_write_msi_msg(entry, &entry->msg); - pci_msix_write_vector_ctrl(entry, entry->pci.msix_ctrl); - } - - pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0); -} - -void pci_restore_msi_state(struct pci_dev *dev) -{ - __pci_restore_msi_state(dev); - __pci_restore_msix_state(dev); -} -EXPORT_SYMBOL_GPL(pci_restore_msi_state); - -static struct msi_desc * -msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd) -{ - struct irq_affinity_desc *masks = NULL; - struct msi_desc *entry; - u16 control; - - if (affd) - masks = irq_create_affinity_masks(nvec, affd); - - /* MSI Entry Initialization */ - entry = alloc_msi_entry(&dev->dev, nvec, masks); - if (!entry) - goto out; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); - /* Lies, damned lies, and MSIs */ - if (dev->dev_flags & PCI_DEV_FLAGS_HAS_MSI_MASKING) - control |= PCI_MSI_FLAGS_MASKBIT; - - entry->pci.msi_attrib.is_msix = 0; - entry->pci.msi_attrib.is_64 = !!(control & PCI_MSI_FLAGS_64BIT); - entry->pci.msi_attrib.is_virtual = 0; - entry->pci.msi_attrib.entry_nr = 0; - entry->pci.msi_attrib.can_mask = !pci_msi_ignore_mask && - !!(control & PCI_MSI_FLAGS_MASKBIT); - entry->pci.msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ - entry->pci.msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; - entry->pci.msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); - - if (control & PCI_MSI_FLAGS_64BIT) - entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_64; - else - entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_32; - - /* Save the initial mask status */ - if (entry->pci.msi_attrib.can_mask) - pci_read_config_dword(dev, entry->pci.mask_pos, &entry->pci.msi_mask); - -out: - kfree(masks); - return entry; -} - -static int msi_verify_entries(struct pci_dev *dev) -{ - struct msi_desc *entry; - - if (!dev->no_64bit_msi) - return 0; - - for_each_pci_msi_entry(entry, dev) { - if (entry->msg.address_hi) { - pci_err(dev, "arch assigned 64-bit MSI address %#x%08x but device only supports 32 bits\n", - entry->msg.address_hi, entry->msg.address_lo); - return -EIO; - } - } - return 0; -} - -/** - * msi_capability_init - configure device's MSI capability structure - * @dev: pointer to the pci_dev data structure of MSI device function - * @nvec: number of interrupts to allocate - * @affd: description of automatic IRQ affinity assignments (may be %NULL) - * - * 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. - */ -static int msi_capability_init(struct pci_dev *dev, int nvec, - struct irq_affinity *affd) -{ - const struct attribute_group **groups; - struct msi_desc *entry; - int ret; - - pci_msi_set_enable(dev, 0); /* Disable MSI during set up */ - - entry = msi_setup_entry(dev, nvec, affd); - if (!entry) - return -ENOMEM; - - /* All MSIs are unmasked by default; mask them all */ - pci_msi_mask(entry, msi_multi_mask(entry)); - - list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); - - /* Configure MSI capability structure */ - ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI); - if (ret) - goto err; - - ret = msi_verify_entries(dev); - if (ret) - goto err; - - groups = msi_populate_sysfs(&dev->dev); - if (IS_ERR(groups)) { - ret = PTR_ERR(groups); - goto err; - } - - dev->msi_irq_groups = groups; - - /* Set MSI enabled bits */ - pci_intx_for_msi(dev, 0); - pci_msi_set_enable(dev, 1); - dev->msi_enabled = 1; - - pcibios_free_irq(dev); - dev->irq = entry->irq; - return 0; - -err: - pci_msi_unmask(entry, msi_multi_mask(entry)); - free_msi_irqs(dev); - return ret; -} - -static void __iomem *msix_map_region(struct pci_dev *dev, - unsigned int nr_entries) -{ - resource_size_t phys_addr; - u32 table_offset; - unsigned long flags; - u8 bir; - - pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE, - &table_offset); - bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); - flags = pci_resource_flags(dev, bir); - if (!flags || (flags & IORESOURCE_UNSET)) - return NULL; - - table_offset &= PCI_MSIX_TABLE_OFFSET; - phys_addr = pci_resource_start(dev, bir) + table_offset; - - return ioremap(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE); -} - -static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, - struct msix_entry *entries, int nvec, - struct irq_affinity *affd) -{ - struct irq_affinity_desc *curmsk, *masks = NULL; - struct msi_desc *entry; - void __iomem *addr; - int ret, i; - int vec_count = pci_msix_vec_count(dev); - - if (affd) - masks = irq_create_affinity_masks(nvec, affd); - - for (i = 0, curmsk = masks; i < nvec; i++) { - entry = alloc_msi_entry(&dev->dev, 1, curmsk); - if (!entry) { - if (!i) - iounmap(base); - else - free_msi_irqs(dev); - /* No enough memory. Don't try again */ - ret = -ENOMEM; - goto out; - } - - entry->pci.msi_attrib.is_msix = 1; - entry->pci.msi_attrib.is_64 = 1; - - if (entries) - entry->pci.msi_attrib.entry_nr = entries[i].entry; - else - entry->pci.msi_attrib.entry_nr = i; - - entry->pci.msi_attrib.is_virtual = - entry->pci.msi_attrib.entry_nr >= vec_count; - - entry->pci.msi_attrib.can_mask = !pci_msi_ignore_mask && - !entry->pci.msi_attrib.is_virtual; - - entry->pci.msi_attrib.default_irq = dev->irq; - entry->pci.mask_base = base; - - if (entry->pci.msi_attrib.can_mask) { - addr = pci_msix_desc_addr(entry); - entry->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL); - } - - list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); - if (masks) - curmsk++; - } - ret = 0; -out: - kfree(masks); - return ret; -} - -static void msix_update_entries(struct pci_dev *dev, struct msix_entry *entries) -{ - struct msi_desc *entry; - - if (entries) { - for_each_pci_msi_entry(entry, dev) { - entries->vector = entry->irq; - entries++; - } - } -} - -static void msix_mask_all(void __iomem *base, int tsize) -{ - u32 ctrl = PCI_MSIX_ENTRY_CTRL_MASKBIT; - int i; - - if (pci_msi_ignore_mask) - return; - - for (i = 0; i < tsize; i++, base += PCI_MSIX_ENTRY_SIZE) - writel(ctrl, base + PCI_MSIX_ENTRY_VECTOR_CTRL); -} - -/** - * msix_capability_init - configure device's MSI-X capability - * @dev: pointer to the pci_dev data structure of MSI-X device function - * @entries: pointer to an array of struct msix_entry entries - * @nvec: number of @entries - * @affd: Optional pointer to enable automatic affinity assignment - * - * Setup the MSI-X capability structure of device function with a - * 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. - **/ -static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, - int nvec, struct irq_affinity *affd) -{ - const struct attribute_group **groups; - void __iomem *base; - int ret, tsize; - u16 control; - - /* - * Some devices require MSI-X to be enabled before the MSI-X - * registers can be accessed. Mask all the vectors to prevent - * interrupts coming in before they're fully set up. - */ - pci_msix_clear_and_set_ctrl(dev, 0, PCI_MSIX_FLAGS_MASKALL | - PCI_MSIX_FLAGS_ENABLE); - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - /* Request & Map MSI-X table region */ - tsize = msix_table_size(control); - base = msix_map_region(dev, tsize); - if (!base) { - ret = -ENOMEM; - goto out_disable; - } - - /* Ensure that all table entries are masked. */ - msix_mask_all(base, tsize); - - ret = msix_setup_entries(dev, base, entries, nvec, affd); - if (ret) - goto out_disable; - - ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX); - if (ret) - goto out_avail; - - /* Check if all MSI entries honor device restrictions */ - ret = msi_verify_entries(dev); - if (ret) - goto out_free; - - msix_update_entries(dev, entries); - - groups = msi_populate_sysfs(&dev->dev); - if (IS_ERR(groups)) { - ret = PTR_ERR(groups); - goto out_free; - } - - dev->msi_irq_groups = groups; - - /* Set MSI-X enabled bits and unmask the function */ - pci_intx_for_msi(dev, 0); - dev->msix_enabled = 1; - pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0); - - pcibios_free_irq(dev); - return 0; - -out_avail: - if (ret < 0) { - /* - * If we had some success, report the number of IRQs - * we succeeded in setting up. - */ - struct msi_desc *entry; - int avail = 0; - - for_each_pci_msi_entry(entry, dev) { - if (entry->irq != 0) - avail++; - } - if (avail != 0) - ret = avail; - } - -out_free: - free_msi_irqs(dev); - -out_disable: - pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0); - - return ret; -} - -/** - * pci_msi_supported - check whether MSI may be enabled on a device - * @dev: pointer to the pci_dev data structure of MSI device function - * @nvec: how many MSIs have been requested? - * - * Look at global flags, the device itself, and its parent buses - * to determine if MSI/-X are supported for the device. If MSI/-X is - * supported return 1, else return 0. - **/ -static int pci_msi_supported(struct pci_dev *dev, int nvec) -{ - struct pci_bus *bus; - - /* MSI must be globally enabled and supported by the device */ - if (!pci_msi_enable) - return 0; - - if (!dev || dev->no_msi) - return 0; - - /* - * 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) - return 0; - - /* - * Any bridge which does NOT route MSI transactions from its - * secondary bus to its primary bus must set NO_MSI flag on - * the secondary pci_bus. - * - * The NO_MSI flag can either be set directly by: - * - arch-specific PCI host bus controller drivers (deprecated) - * - quirks for specific PCI bridges - * - * or indirectly by platform-specific PCI host bridge drivers by - * advertising the 'msi_domain' property, which results in - * the NO_MSI flag when no MSI domain is found for this bridge - * at probe time. - */ - for (bus = dev->bus; bus; bus = bus->parent) - if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI) - return 0; - - return 1; -} - -/** - * 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); - -static void pci_msi_shutdown(struct pci_dev *dev) -{ - struct msi_desc *desc; - - if (!pci_msi_enable || !dev || !dev->msi_enabled) - return; - - BUG_ON(list_empty(dev_to_msi_list(&dev->dev))); - desc = first_pci_msi_entry(dev); - - pci_msi_set_enable(dev, 0); - pci_intx_for_msi(dev, 1); - dev->msi_enabled = 0; - - /* Return the device with MSI unmasked as initial states */ - pci_msi_unmask(desc, msi_multi_mask(desc)); - - /* Restore dev->irq to its default pin-assertion IRQ */ - dev->irq = desc->pci.msi_attrib.default_irq; - pcibios_alloc_irq(dev); -} - -void pci_disable_msi(struct pci_dev *dev) -{ - if (!pci_msi_enable || !dev || !dev->msi_enabled) - return; - - pci_msi_shutdown(dev); - free_msi_irqs(dev); -} -EXPORT_SYMBOL(pci_disable_msi); - -/** - * pci_msix_vec_count - return the number of device's MSI-X table entries - * @dev: pointer to the pci_dev data structure of MSI-X device function - * 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) -{ - u16 control; - - if (!dev->msix_cap) - return -EINVAL; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); - return msix_table_size(control); -} -EXPORT_SYMBOL(pci_msix_vec_count); - -static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, - int nvec, struct irq_affinity *affd, int flags) -{ - int nr_entries; - int i, j; - - if (!pci_msi_supported(dev, nvec) || dev->current_state != PCI_D0) - return -EINVAL; - - nr_entries = pci_msix_vec_count(dev); - if (nr_entries < 0) - return nr_entries; - if (nvec > nr_entries && !(flags & PCI_IRQ_VIRTUAL)) - return nr_entries; - - 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 */ - } - } - } - - /* Check whether driver already requested for MSI IRQ */ - if (dev->msi_enabled) { - pci_info(dev, "can't enable MSI-X (MSI IRQ already assigned)\n"); - return -EINVAL; - } - return msix_capability_init(dev, entries, nvec, affd); -} - -static void pci_msix_shutdown(struct pci_dev *dev) -{ - struct msi_desc *entry; - - if (!pci_msi_enable || !dev || !dev->msix_enabled) - return; - - if (pci_dev_is_disconnected(dev)) { - dev->msix_enabled = 0; - return; - } - - /* Return the device with MSI-X masked as initial states */ - for_each_pci_msi_entry(entry, dev) - pci_msix_mask(entry); - - pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0); - pci_intx_for_msi(dev, 1); - dev->msix_enabled = 0; - pcibios_alloc_irq(dev); -} - -void pci_disable_msix(struct pci_dev *dev) -{ - if (!pci_msi_enable || !dev || !dev->msix_enabled) - return; - - pci_msix_shutdown(dev); - free_msi_irqs(dev); -} -EXPORT_SYMBOL(pci_disable_msix); - -void pci_no_msi(void) -{ - pci_msi_enable = 0; -} - -/** - * 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) -{ - return pci_msi_enable; -} -EXPORT_SYMBOL(pci_msi_enabled); - -static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, - struct irq_affinity *affd) -{ - int nvec; - int rc; - - if (!pci_msi_supported(dev, minvec) || dev->current_state != PCI_D0) - return -EINVAL; - - /* Check whether driver already requested MSI-X IRQs */ - if (dev->msix_enabled) { - pci_info(dev, "can't enable MSI (MSI-X already enabled)\n"); - return -EINVAL; - } - - if (maxvec < minvec) - return -ERANGE; - - if (WARN_ON_ONCE(dev->msi_enabled)) - return -EINVAL; - - nvec = pci_msi_vec_count(dev); - if (nvec < 0) - return nvec; - if (nvec < minvec) - return -ENOSPC; - - if (nvec > maxvec) - nvec = maxvec; - - for (;;) { - if (affd) { - nvec = irq_calc_affinity_vectors(minvec, nvec, affd); - if (nvec < minvec) - return -ENOSPC; - } - - rc = msi_capability_init(dev, nvec, affd); - if (rc == 0) - return nvec; - - if (rc < 0) - return rc; - if (rc < minvec) - return -ENOSPC; - - nvec = rc; - } -} - -/* deprecated, don't use */ -int pci_enable_msi(struct pci_dev *dev) -{ - int rc = __pci_enable_msi_range(dev, 1, 1, NULL); - if (rc < 0) - return rc; - return 0; -} -EXPORT_SYMBOL(pci_enable_msi); - -static int __pci_enable_msix_range(struct pci_dev *dev, - struct msix_entry *entries, int minvec, - int maxvec, struct irq_affinity *affd, - int flags) -{ - int rc, nvec = maxvec; - - if (maxvec < minvec) - return -ERANGE; - - if (WARN_ON_ONCE(dev->msix_enabled)) - return -EINVAL; - - for (;;) { - if (affd) { - nvec = irq_calc_affinity_vectors(minvec, nvec, affd); - if (nvec < minvec) - return -ENOSPC; - } - - rc = __pci_enable_msix(dev, entries, nvec, affd, flags); - if (rc == 0) - return nvec; - - if (rc < 0) - return rc; - if (rc < minvec) - return -ENOSPC; - - nvec = rc; - } -} - -/** - * 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, - int minvec, int maxvec) -{ - return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL, 0); -} -EXPORT_SYMBOL(pci_enable_msix_range); - -/** - * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device - * @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 - * @affd: optional description of the affinity requirements - * - * 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. - */ -int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, - unsigned int max_vecs, unsigned int flags, - struct irq_affinity *affd) -{ - struct irq_affinity msi_default_affd = {0}; - int nvecs = -ENOSPC; - - if (flags & PCI_IRQ_AFFINITY) { - if (!affd) - affd = &msi_default_affd; - } else { - if (WARN_ON(affd)) - affd = NULL; - } - - if (flags & PCI_IRQ_MSIX) { - nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, - affd, flags); - if (nvecs > 0) - return nvecs; - } - - if (flags & PCI_IRQ_MSI) { - nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd); - if (nvecs > 0) - return nvecs; - } - - /* use legacy IRQ if allowed */ - if (flags & PCI_IRQ_LEGACY) { - if (min_vecs == 1 && dev->irq) { - /* - * Invoke the affinity spreading logic to ensure that - * the device driver can adjust queue configuration - * for the single interrupt case. - */ - if (affd) - irq_create_affinity_masks(1, affd); - pci_intx(dev, 1); - return 1; - } - } - - return nvecs; -} -EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity); - -/** - * 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: Interrupt vector index (0-based) - * - * @nr has the following meanings depending on the interrupt mode: - * MSI-X: The index in the MSI-X vector table - * MSI: The index of the enabled MSI vectors - * INTx: Must be 0 - * - * Return: The Linux interrupt number or -EINVAl if @nr is out of range. - */ -int pci_irq_vector(struct pci_dev *dev, unsigned int nr) -{ - if (dev->msix_enabled) { - struct msi_desc *entry; - - for_each_pci_msi_entry(entry, dev) { - if (entry->pci.msi_attrib.entry_nr == nr) - return entry->irq; - } - 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); - -/** - * 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). - * - * @nr has the following meanings depending on the interrupt mode: - * MSI-X: The index in the MSI-X vector table - * MSI: The index of the enabled MSI vectors - * INTx: Must be 0 - * - * Return: A cpumask pointer or NULL if @nr is out of range - */ -const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr) -{ - if (dev->msix_enabled) { - struct msi_desc *entry; - - for_each_pci_msi_entry(entry, dev) { - if (entry->pci.msi_attrib.entry_nr == nr) - return &entry->affinity->mask; - } - WARN_ON_ONCE(1); - return NULL; - } else if (dev->msi_enabled) { - struct msi_desc *entry = first_pci_msi_entry(dev); - - if (WARN_ON_ONCE(!entry || !entry->affinity || - nr >= entry->nvec_used)) - return NULL; - - return &entry->affinity[nr].mask; - } else { - return cpu_possible_mask; - } -} -EXPORT_SYMBOL(pci_irq_get_affinity); - -struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc) -{ - return to_pci_dev(desc->dev); -} -EXPORT_SYMBOL(msi_desc_to_pci_dev); - -#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 - */ -static void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg) -{ - struct msi_desc *desc = irq_data_get_msi_desc(irq_data); - - /* - * 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 - * @desc: Pointer to the MSI descriptor - * - * The ID number is only used within the irqdomain. - */ -static irq_hw_number_t pci_msi_domain_calc_hwirq(struct msi_desc *desc) -{ - struct pci_dev *dev = msi_desc_to_pci_dev(desc); - - return (irq_hw_number_t)desc->pci.msi_attrib.entry_nr | - pci_dev_id(dev) << 11 | - (pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27; -} - -static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc) -{ - return !desc->pci.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)); - - /* Special handling to support __pci_enable_msi_range() */ - if (pci_msi_desc_is_multi_msi(desc) && - !(info->flags & MSI_FLAG_MULTI_PCI_MSI)) - return 1; - else if (desc->pci.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) -{ - /* Special handling to support __pci_enable_msi_range() */ - if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC) - return 1; - - return error; -} - -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(desc); -} - -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; - if (!chip->irq_mask) - chip->irq_mask = pci_msi_mask_irq; - if (!chip->irq_unmask) - chip->irq_unmask = pci_msi_unmask_irq; -} - -/** - * pci_msi_create_irq_domain - Create a MSI interrupt domain - * @fwnode: Optional fwnode of the interrupt controller - * @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. - */ -struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode, - struct msi_domain_info *info, - struct irq_domain *parent) -{ - struct irq_domain *domain; - - if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE)) - info->flags &= ~MSI_FLAG_LEVEL_CAPABLE; - - 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); - - info->flags |= MSI_FLAG_ACTIVATE_EARLY; - if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE)) - info->flags |= MSI_FLAG_MUST_REACTIVATE; - - /* PCI-MSI is oneshot-safe */ - info->chip->flags |= IRQCHIP_ONESHOT_SAFE; - - domain = msi_create_irq_domain(fwnode, info, parent); - if (!domain) - return NULL; - - irq_domain_update_bus_token(domain, DOMAIN_BUS_PCI_MSI); - return domain; -} -EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain); - -/* - * 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... - */ -static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data) -{ - u32 *pa = data; - u8 bus = PCI_BUS_NUM(*pa); - - if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus) - *pa = alias; - - return 0; -} - -/** - * 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; - u32 rid = pci_dev_id(pdev); - - pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); - - of_node = irq_domain_get_of_node(domain); - rid = of_node ? of_msi_map_id(&pdev->dev, of_node, rid) : - iort_msi_map_id(&pdev->dev, rid); - - return rid; -} - -/** - * 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 - * (i.e. not one that is set as a default). - * - * Returns: The corresponding MSI domain or NULL if none has been found. - */ -struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) -{ - struct irq_domain *dom; - u32 rid = pci_dev_id(pdev); - - pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); - dom = of_msi_map_get_device_domain(&pdev->dev, rid, DOMAIN_BUS_PCI_MSI); - if (!dom) - dom = iort_get_device_domain(&pdev->dev, rid, - DOMAIN_BUS_PCI_MSI); - return dom; -} - -/** - * pci_dev_has_special_msi_domain - Check whether the device is handled by - * a non-standard PCI-MSI domain - * @pdev: The PCI device to check. - * - * Returns: True if the device irqdomain or the bus irqdomain is - * non-standard PCI/MSI. - */ -bool pci_dev_has_special_msi_domain(struct pci_dev *pdev) -{ - struct irq_domain *dom = dev_get_msi_domain(&pdev->dev); - - if (!dom) - dom = dev_get_msi_domain(&pdev->bus->dev); - - if (!dom) - return true; - - return dom->bus_token != DOMAIN_BUS_PCI_MSI; -} - -#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ -#endif /* CONFIG_PCI_MSI */ - -void pci_msi_init(struct pci_dev *dev) -{ - u16 ctrl; - - /* - * Disable the MSI hardware to avoid screaming interrupts - * during boot. This is the power on reset default so - * usually this should be a noop. - */ - dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI); - if (!dev->msi_cap) - return; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl); - if (ctrl & PCI_MSI_FLAGS_ENABLE) - pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, - ctrl & ~PCI_MSI_FLAGS_ENABLE); - - if (!(ctrl & PCI_MSI_FLAGS_64BIT)) - dev->no_64bit_msi = 1; -} - -void pci_msix_init(struct pci_dev *dev) -{ - u16 ctrl; - - dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX); - if (!dev->msix_cap) - return; - - pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl); - if (ctrl & PCI_MSIX_FLAGS_ENABLE) - pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, - ctrl & ~PCI_MSIX_FLAGS_ENABLE); -} diff --git a/drivers/pci/msi/Makefile b/drivers/pci/msi/Makefile new file mode 100644 index 0000000..79a6013 --- /dev/null +++ b/drivers/pci/msi/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the PCI/MSI +obj-$(CONFIG_PCI) += msi.o diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c new file mode 100644 index 0000000..00233b0 --- /dev/null +++ b/drivers/pci/msi/msi.c @@ -0,0 +1,1532 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI Message Signaled Interrupt (MSI) + * + * Copyright (C) 2003-2004 Intel + * Copyright (C) Tom Long Nguyen (tom.l.nguyen@xxxxxxxxx) + * Copyright (C) 2016 Christoph Hellwig. + */ + +#include <linux/acpi_iort.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/msi.h> +#include <linux/of_irq.h> +#include <linux/pci.h> + +#include "../pci.h" + +#ifdef CONFIG_PCI_MSI + +static int pci_msi_enable = 1; +int pci_msi_ignore_mask; + +#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) + +#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; + + domain = dev_get_msi_domain(&dev->dev); + if (domain && irq_domain_is_hierarchy(domain)) + return msi_domain_alloc_irqs(domain, &dev->dev, nvec); + + return arch_setup_msi_irqs(dev, nvec, type); +} + +static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) +{ + struct irq_domain *domain; + + domain = dev_get_msi_domain(&dev->dev); + if (domain && irq_domain_is_hierarchy(domain)) + msi_domain_free_irqs(domain, &dev->dev); + 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 + +#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS +/* Arch hooks */ +int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) +{ + return -EINVAL; +} + +void __weak arch_teardown_msi_irq(unsigned int irq) +{ +} + +int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +{ + struct msi_desc *entry; + int ret; + + /* + * 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; + + for_each_pci_msi_entry(entry, dev) { + ret = arch_setup_msi_irq(dev, entry); + if (ret < 0) + return ret; + if (ret > 0) + return -ENOSPC; + } + + return 0; +} + +void __weak arch_teardown_msi_irqs(struct pci_dev *dev) +{ + int i; + struct msi_desc *entry; + + for_each_pci_msi_entry(entry, dev) + if (entry->irq) + for (i = 0; i < entry->nvec_used; i++) + arch_teardown_msi_irq(entry->irq + i); +} +#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */ + +/* + * 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. + */ +static inline __attribute_const__ u32 msi_multi_mask(struct msi_desc *desc) +{ + /* Don't shift by >= width of type */ + if (desc->pci.msi_attrib.multi_cap >= 5) + return 0xffffffff; + return (1 << (1 << desc->pci.msi_attrib.multi_cap)) - 1; +} + +static noinline void pci_msi_update_mask(struct msi_desc *desc, u32 clear, u32 set) +{ + raw_spinlock_t *lock = &desc->dev->msi_lock; + unsigned long flags; + + if (!desc->pci.msi_attrib.can_mask) + return; + + raw_spin_lock_irqsave(lock, flags); + desc->pci.msi_mask &= ~clear; + desc->pci.msi_mask |= set; + pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->pci.mask_pos, + desc->pci.msi_mask); + raw_spin_unlock_irqrestore(lock, flags); +} + +static inline void pci_msi_mask(struct msi_desc *desc, u32 mask) +{ + pci_msi_update_mask(desc, 0, mask); +} + +static inline void pci_msi_unmask(struct msi_desc *desc, u32 mask) +{ + pci_msi_update_mask(desc, mask, 0); +} + +static inline void __iomem *pci_msix_desc_addr(struct msi_desc *desc) +{ + return desc->pci.mask_base + desc->pci.msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; +} + +/* + * 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. + * It does not affect the msi_desc::msix_ctrl cache either. Use with care! + */ +static void pci_msix_write_vector_ctrl(struct msi_desc *desc, u32 ctrl) +{ + void __iomem *desc_addr = pci_msix_desc_addr(desc); + + if (desc->pci.msi_attrib.can_mask) + writel(ctrl, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL); +} + +static inline void pci_msix_mask(struct msi_desc *desc) +{ + desc->pci.msix_ctrl |= PCI_MSIX_ENTRY_CTRL_MASKBIT; + pci_msix_write_vector_ctrl(desc, desc->pci.msix_ctrl); + /* Flush write to device */ + readl(desc->pci.mask_base); +} + +static inline void pci_msix_unmask(struct msi_desc *desc) +{ + desc->pci.msix_ctrl &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; + pci_msix_write_vector_ctrl(desc, desc->pci.msix_ctrl); +} + +static void __pci_msi_mask_desc(struct msi_desc *desc, u32 mask) +{ + if (desc->pci.msi_attrib.is_msix) + pci_msix_mask(desc); + else + pci_msi_mask(desc, mask); +} + +static void __pci_msi_unmask_desc(struct msi_desc *desc, u32 mask) +{ + if (desc->pci.msi_attrib.is_msix) + pci_msix_unmask(desc); + else + pci_msi_unmask(desc, mask); +} + +/** + * 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) +{ + struct msi_desc *desc = irq_data_get_msi_desc(data); + + __pci_msi_mask_desc(desc, BIT(data->irq - desc->irq)); +} +EXPORT_SYMBOL_GPL(pci_msi_mask_irq); + +/** + * 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) +{ + struct msi_desc *desc = irq_data_get_msi_desc(data); + + __pci_msi_unmask_desc(desc, BIT(data->irq - desc->irq)); +} +EXPORT_SYMBOL_GPL(pci_msi_unmask_irq); + +void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg) +{ + struct pci_dev *dev = msi_desc_to_pci_dev(entry); + + BUG_ON(dev->current_state != PCI_D0); + + if (entry->pci.msi_attrib.is_msix) { + void __iomem *base = pci_msix_desc_addr(entry); + + if (WARN_ON_ONCE(entry->pci.msi_attrib.is_virtual)) + return; + + 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 { + int pos = dev->msi_cap; + u16 data; + + pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, + &msg->address_lo); + if (entry->pci.msi_attrib.is_64) { + pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, + &msg->address_hi); + pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data); + } else { + msg->address_hi = 0; + pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data); + } + msg->data = data; + } +} + +void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg) +{ + struct pci_dev *dev = msi_desc_to_pci_dev(entry); + + if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) { + /* Don't touch the hardware now */ + } else if (entry->pci.msi_attrib.is_msix) { + void __iomem *base = pci_msix_desc_addr(entry); + u32 ctrl = entry->pci.msix_ctrl; + bool unmasked = !(ctrl & PCI_MSIX_ENTRY_CTRL_MASKBIT); + + if (entry->pci.msi_attrib.is_virtual) + goto skip; + + /* + * The specification mandates that the entry is masked + * when the message is modified: + * + * "If software changes the Address or Data value of an + * entry while the entry is unmasked, the result is + * undefined." + */ + if (unmasked) + pci_msix_write_vector_ctrl(entry, ctrl | PCI_MSIX_ENTRY_CTRL_MASKBIT); + + 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); + + if (unmasked) + pci_msix_write_vector_ctrl(entry, ctrl); + + /* Ensure that the writes are visible in the device */ + readl(base + PCI_MSIX_ENTRY_DATA); + } else { + int pos = dev->msi_cap; + u16 msgctl; + + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); + msgctl &= ~PCI_MSI_FLAGS_QSIZE; + msgctl |= entry->pci.msi_attrib.multiple << 4; + pci_write_config_word(dev, pos + PCI_MSI_FLAGS, msgctl); + + pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, + msg->address_lo); + if (entry->pci.msi_attrib.is_64) { + pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, + msg->address_hi); + pci_write_config_word(dev, pos + PCI_MSI_DATA_64, + msg->data); + } else { + pci_write_config_word(dev, pos + PCI_MSI_DATA_32, + msg->data); + } + /* Ensure that the writes are visible in the device */ + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); + } + +skip: + entry->msg = *msg; + + if (entry->write_msi_msg) + entry->write_msi_msg(entry, entry->write_msi_msg_data); + +} + +void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg) +{ + struct msi_desc *entry = irq_get_msi_desc(irq); + + __pci_write_msi_msg(entry, msg); +} +EXPORT_SYMBOL_GPL(pci_write_msi_msg); + +static void free_msi_irqs(struct pci_dev *dev) +{ + struct list_head *msi_list = dev_to_msi_list(&dev->dev); + struct msi_desc *entry, *tmp; + int i; + + for_each_pci_msi_entry(entry, dev) + if (entry->irq) + for (i = 0; i < entry->nvec_used; i++) + BUG_ON(irq_has_action(entry->irq + i)); + + if (dev->msi_irq_groups) { + msi_destroy_sysfs(&dev->dev, dev->msi_irq_groups); + dev->msi_irq_groups = NULL; + } + + pci_msi_teardown_msi_irqs(dev); + + list_for_each_entry_safe(entry, tmp, msi_list, list) { + if (entry->pci.msi_attrib.is_msix) { + if (list_is_last(&entry->list, msi_list)) + iounmap(entry->pci.mask_base); + } + + list_del(&entry->list); + free_msi_entry(entry); + } +} + +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); +} + +static void pci_msi_set_enable(struct pci_dev *dev, int enable) +{ + u16 control; + + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); + control &= ~PCI_MSI_FLAGS_ENABLE; + if (enable) + control |= PCI_MSI_FLAGS_ENABLE; + pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); +} + +/* + * Architecture override returns true when the PCI MSI message should be + * written by the generic restore function. + */ +bool __weak arch_restore_msi_irqs(struct pci_dev *dev) +{ + return true; +} + +static void __pci_restore_msi_state(struct pci_dev *dev) +{ + struct msi_desc *entry; + u16 control; + + if (!dev->msi_enabled) + return; + + entry = irq_get_msi_desc(dev->irq); + + pci_intx_for_msi(dev, 0); + pci_msi_set_enable(dev, 0); + if (arch_restore_msi_irqs(dev)) + __pci_write_msi_msg(entry, &entry->msg); + + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); + pci_msi_update_mask(entry, 0, 0); + control &= ~PCI_MSI_FLAGS_QSIZE; + control |= (entry->pci.msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE; + pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); +} + +static void pci_msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set) +{ + u16 ctrl; + + pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl); + ctrl &= ~clear; + ctrl |= set; + pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl); +} + +static void __pci_restore_msix_state(struct pci_dev *dev) +{ + struct msi_desc *entry; + bool write_msg; + + if (!dev->msix_enabled) + return; + BUG_ON(list_empty(dev_to_msi_list(&dev->dev))); + + /* route the table */ + pci_intx_for_msi(dev, 0); + pci_msix_clear_and_set_ctrl(dev, 0, + PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL); + + write_msg = arch_restore_msi_irqs(dev); + + for_each_pci_msi_entry(entry, dev) { + if (write_msg) + __pci_write_msi_msg(entry, &entry->msg); + pci_msix_write_vector_ctrl(entry, entry->pci.msix_ctrl); + } + + pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0); +} + +void pci_restore_msi_state(struct pci_dev *dev) +{ + __pci_restore_msi_state(dev); + __pci_restore_msix_state(dev); +} +EXPORT_SYMBOL_GPL(pci_restore_msi_state); + +static struct msi_desc * +msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd) +{ + struct irq_affinity_desc *masks = NULL; + struct msi_desc *entry; + u16 control; + + if (affd) + masks = irq_create_affinity_masks(nvec, affd); + + /* MSI Entry Initialization */ + entry = alloc_msi_entry(&dev->dev, nvec, masks); + if (!entry) + goto out; + + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); + /* Lies, damned lies, and MSIs */ + if (dev->dev_flags & PCI_DEV_FLAGS_HAS_MSI_MASKING) + control |= PCI_MSI_FLAGS_MASKBIT; + + entry->pci.msi_attrib.is_msix = 0; + entry->pci.msi_attrib.is_64 = !!(control & PCI_MSI_FLAGS_64BIT); + entry->pci.msi_attrib.is_virtual = 0; + entry->pci.msi_attrib.entry_nr = 0; + entry->pci.msi_attrib.can_mask = !pci_msi_ignore_mask && + !!(control & PCI_MSI_FLAGS_MASKBIT); + entry->pci.msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ + entry->pci.msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1; + entry->pci.msi_attrib.multiple = ilog2(__roundup_pow_of_two(nvec)); + + if (control & PCI_MSI_FLAGS_64BIT) + entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_64; + else + entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_32; + + /* Save the initial mask status */ + if (entry->pci.msi_attrib.can_mask) + pci_read_config_dword(dev, entry->pci.mask_pos, &entry->pci.msi_mask); + +out: + kfree(masks); + return entry; +} + +static int msi_verify_entries(struct pci_dev *dev) +{ + struct msi_desc *entry; + + if (!dev->no_64bit_msi) + return 0; + + for_each_pci_msi_entry(entry, dev) { + if (entry->msg.address_hi) { + pci_err(dev, "arch assigned 64-bit MSI address %#x%08x but device only supports 32 bits\n", + entry->msg.address_hi, entry->msg.address_lo); + return -EIO; + } + } + return 0; +} + +/** + * msi_capability_init - configure device's MSI capability structure + * @dev: pointer to the pci_dev data structure of MSI device function + * @nvec: number of interrupts to allocate + * @affd: description of automatic IRQ affinity assignments (may be %NULL) + * + * 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. + */ +static int msi_capability_init(struct pci_dev *dev, int nvec, + struct irq_affinity *affd) +{ + const struct attribute_group **groups; + struct msi_desc *entry; + int ret; + + pci_msi_set_enable(dev, 0); /* Disable MSI during set up */ + + entry = msi_setup_entry(dev, nvec, affd); + if (!entry) + return -ENOMEM; + + /* All MSIs are unmasked by default; mask them all */ + pci_msi_mask(entry, msi_multi_mask(entry)); + + list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); + + /* Configure MSI capability structure */ + ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI); + if (ret) + goto err; + + ret = msi_verify_entries(dev); + if (ret) + goto err; + + groups = msi_populate_sysfs(&dev->dev); + if (IS_ERR(groups)) { + ret = PTR_ERR(groups); + goto err; + } + + dev->msi_irq_groups = groups; + + /* Set MSI enabled bits */ + pci_intx_for_msi(dev, 0); + pci_msi_set_enable(dev, 1); + dev->msi_enabled = 1; + + pcibios_free_irq(dev); + dev->irq = entry->irq; + return 0; + +err: + pci_msi_unmask(entry, msi_multi_mask(entry)); + free_msi_irqs(dev); + return ret; +} + +static void __iomem *msix_map_region(struct pci_dev *dev, + unsigned int nr_entries) +{ + resource_size_t phys_addr; + u32 table_offset; + unsigned long flags; + u8 bir; + + pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE, + &table_offset); + bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); + flags = pci_resource_flags(dev, bir); + if (!flags || (flags & IORESOURCE_UNSET)) + return NULL; + + table_offset &= PCI_MSIX_TABLE_OFFSET; + phys_addr = pci_resource_start(dev, bir) + table_offset; + + return ioremap(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE); +} + +static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, + struct msix_entry *entries, int nvec, + struct irq_affinity *affd) +{ + struct irq_affinity_desc *curmsk, *masks = NULL; + struct msi_desc *entry; + void __iomem *addr; + int ret, i; + int vec_count = pci_msix_vec_count(dev); + + if (affd) + masks = irq_create_affinity_masks(nvec, affd); + + for (i = 0, curmsk = masks; i < nvec; i++) { + entry = alloc_msi_entry(&dev->dev, 1, curmsk); + if (!entry) { + if (!i) + iounmap(base); + else + free_msi_irqs(dev); + /* No enough memory. Don't try again */ + ret = -ENOMEM; + goto out; + } + + entry->pci.msi_attrib.is_msix = 1; + entry->pci.msi_attrib.is_64 = 1; + + if (entries) + entry->pci.msi_attrib.entry_nr = entries[i].entry; + else + entry->pci.msi_attrib.entry_nr = i; + + entry->pci.msi_attrib.is_virtual = + entry->pci.msi_attrib.entry_nr >= vec_count; + + entry->pci.msi_attrib.can_mask = !pci_msi_ignore_mask && + !entry->pci.msi_attrib.is_virtual; + + entry->pci.msi_attrib.default_irq = dev->irq; + entry->pci.mask_base = base; + + if (entry->pci.msi_attrib.can_mask) { + addr = pci_msix_desc_addr(entry); + entry->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL); + } + + list_add_tail(&entry->list, dev_to_msi_list(&dev->dev)); + if (masks) + curmsk++; + } + ret = 0; +out: + kfree(masks); + return ret; +} + +static void msix_update_entries(struct pci_dev *dev, struct msix_entry *entries) +{ + struct msi_desc *entry; + + if (entries) { + for_each_pci_msi_entry(entry, dev) { + entries->vector = entry->irq; + entries++; + } + } +} + +static void msix_mask_all(void __iomem *base, int tsize) +{ + u32 ctrl = PCI_MSIX_ENTRY_CTRL_MASKBIT; + int i; + + if (pci_msi_ignore_mask) + return; + + for (i = 0; i < tsize; i++, base += PCI_MSIX_ENTRY_SIZE) + writel(ctrl, base + PCI_MSIX_ENTRY_VECTOR_CTRL); +} + +/** + * msix_capability_init - configure device's MSI-X capability + * @dev: pointer to the pci_dev data structure of MSI-X device function + * @entries: pointer to an array of struct msix_entry entries + * @nvec: number of @entries + * @affd: Optional pointer to enable automatic affinity assignment + * + * Setup the MSI-X capability structure of device function with a + * 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. + **/ +static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, + int nvec, struct irq_affinity *affd) +{ + const struct attribute_group **groups; + void __iomem *base; + int ret, tsize; + u16 control; + + /* + * Some devices require MSI-X to be enabled before the MSI-X + * registers can be accessed. Mask all the vectors to prevent + * interrupts coming in before they're fully set up. + */ + pci_msix_clear_and_set_ctrl(dev, 0, PCI_MSIX_FLAGS_MASKALL | + PCI_MSIX_FLAGS_ENABLE); + + pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); + /* Request & Map MSI-X table region */ + tsize = msix_table_size(control); + base = msix_map_region(dev, tsize); + if (!base) { + ret = -ENOMEM; + goto out_disable; + } + + /* Ensure that all table entries are masked. */ + msix_mask_all(base, tsize); + + ret = msix_setup_entries(dev, base, entries, nvec, affd); + if (ret) + goto out_disable; + + ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX); + if (ret) + goto out_avail; + + /* Check if all MSI entries honor device restrictions */ + ret = msi_verify_entries(dev); + if (ret) + goto out_free; + + msix_update_entries(dev, entries); + + groups = msi_populate_sysfs(&dev->dev); + if (IS_ERR(groups)) { + ret = PTR_ERR(groups); + goto out_free; + } + + dev->msi_irq_groups = groups; + + /* Set MSI-X enabled bits and unmask the function */ + pci_intx_for_msi(dev, 0); + dev->msix_enabled = 1; + pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0); + + pcibios_free_irq(dev); + return 0; + +out_avail: + if (ret < 0) { + /* + * If we had some success, report the number of IRQs + * we succeeded in setting up. + */ + struct msi_desc *entry; + int avail = 0; + + for_each_pci_msi_entry(entry, dev) { + if (entry->irq != 0) + avail++; + } + if (avail != 0) + ret = avail; + } + +out_free: + free_msi_irqs(dev); + +out_disable: + pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0); + + return ret; +} + +/** + * pci_msi_supported - check whether MSI may be enabled on a device + * @dev: pointer to the pci_dev data structure of MSI device function + * @nvec: how many MSIs have been requested? + * + * Look at global flags, the device itself, and its parent buses + * to determine if MSI/-X are supported for the device. If MSI/-X is + * supported return 1, else return 0. + **/ +static int pci_msi_supported(struct pci_dev *dev, int nvec) +{ + struct pci_bus *bus; + + /* MSI must be globally enabled and supported by the device */ + if (!pci_msi_enable) + return 0; + + if (!dev || dev->no_msi) + return 0; + + /* + * 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) + return 0; + + /* + * Any bridge which does NOT route MSI transactions from its + * secondary bus to its primary bus must set NO_MSI flag on + * the secondary pci_bus. + * + * The NO_MSI flag can either be set directly by: + * - arch-specific PCI host bus controller drivers (deprecated) + * - quirks for specific PCI bridges + * + * or indirectly by platform-specific PCI host bridge drivers by + * advertising the 'msi_domain' property, which results in + * the NO_MSI flag when no MSI domain is found for this bridge + * at probe time. + */ + for (bus = dev->bus; bus; bus = bus->parent) + if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI) + return 0; + + return 1; +} + +/** + * 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); + +static void pci_msi_shutdown(struct pci_dev *dev) +{ + struct msi_desc *desc; + + if (!pci_msi_enable || !dev || !dev->msi_enabled) + return; + + BUG_ON(list_empty(dev_to_msi_list(&dev->dev))); + desc = first_pci_msi_entry(dev); + + pci_msi_set_enable(dev, 0); + pci_intx_for_msi(dev, 1); + dev->msi_enabled = 0; + + /* Return the device with MSI unmasked as initial states */ + pci_msi_unmask(desc, msi_multi_mask(desc)); + + /* Restore dev->irq to its default pin-assertion IRQ */ + dev->irq = desc->pci.msi_attrib.default_irq; + pcibios_alloc_irq(dev); +} + +void pci_disable_msi(struct pci_dev *dev) +{ + if (!pci_msi_enable || !dev || !dev->msi_enabled) + return; + + pci_msi_shutdown(dev); + free_msi_irqs(dev); +} +EXPORT_SYMBOL(pci_disable_msi); + +/** + * pci_msix_vec_count - return the number of device's MSI-X table entries + * @dev: pointer to the pci_dev data structure of MSI-X device function + * 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) +{ + u16 control; + + if (!dev->msix_cap) + return -EINVAL; + + pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); + return msix_table_size(control); +} +EXPORT_SYMBOL(pci_msix_vec_count); + +static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, + int nvec, struct irq_affinity *affd, int flags) +{ + int nr_entries; + int i, j; + + if (!pci_msi_supported(dev, nvec) || dev->current_state != PCI_D0) + return -EINVAL; + + nr_entries = pci_msix_vec_count(dev); + if (nr_entries < 0) + return nr_entries; + if (nvec > nr_entries && !(flags & PCI_IRQ_VIRTUAL)) + return nr_entries; + + 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 */ + } + } + } + + /* Check whether driver already requested for MSI IRQ */ + if (dev->msi_enabled) { + pci_info(dev, "can't enable MSI-X (MSI IRQ already assigned)\n"); + return -EINVAL; + } + return msix_capability_init(dev, entries, nvec, affd); +} + +static void pci_msix_shutdown(struct pci_dev *dev) +{ + struct msi_desc *entry; + + if (!pci_msi_enable || !dev || !dev->msix_enabled) + return; + + if (pci_dev_is_disconnected(dev)) { + dev->msix_enabled = 0; + return; + } + + /* Return the device with MSI-X masked as initial states */ + for_each_pci_msi_entry(entry, dev) + pci_msix_mask(entry); + + pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0); + pci_intx_for_msi(dev, 1); + dev->msix_enabled = 0; + pcibios_alloc_irq(dev); +} + +void pci_disable_msix(struct pci_dev *dev) +{ + if (!pci_msi_enable || !dev || !dev->msix_enabled) + return; + + pci_msix_shutdown(dev); + free_msi_irqs(dev); +} +EXPORT_SYMBOL(pci_disable_msix); + +void pci_no_msi(void) +{ + pci_msi_enable = 0; +} + +/** + * 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) +{ + return pci_msi_enable; +} +EXPORT_SYMBOL(pci_msi_enabled); + +static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, + struct irq_affinity *affd) +{ + int nvec; + int rc; + + if (!pci_msi_supported(dev, minvec) || dev->current_state != PCI_D0) + return -EINVAL; + + /* Check whether driver already requested MSI-X IRQs */ + if (dev->msix_enabled) { + pci_info(dev, "can't enable MSI (MSI-X already enabled)\n"); + return -EINVAL; + } + + if (maxvec < minvec) + return -ERANGE; + + if (WARN_ON_ONCE(dev->msi_enabled)) + return -EINVAL; + + nvec = pci_msi_vec_count(dev); + if (nvec < 0) + return nvec; + if (nvec < minvec) + return -ENOSPC; + + if (nvec > maxvec) + nvec = maxvec; + + for (;;) { + if (affd) { + nvec = irq_calc_affinity_vectors(minvec, nvec, affd); + if (nvec < minvec) + return -ENOSPC; + } + + rc = msi_capability_init(dev, nvec, affd); + if (rc == 0) + return nvec; + + if (rc < 0) + return rc; + if (rc < minvec) + return -ENOSPC; + + nvec = rc; + } +} + +/* deprecated, don't use */ +int pci_enable_msi(struct pci_dev *dev) +{ + int rc = __pci_enable_msi_range(dev, 1, 1, NULL); + if (rc < 0) + return rc; + return 0; +} +EXPORT_SYMBOL(pci_enable_msi); + +static int __pci_enable_msix_range(struct pci_dev *dev, + struct msix_entry *entries, int minvec, + int maxvec, struct irq_affinity *affd, + int flags) +{ + int rc, nvec = maxvec; + + if (maxvec < minvec) + return -ERANGE; + + if (WARN_ON_ONCE(dev->msix_enabled)) + return -EINVAL; + + for (;;) { + if (affd) { + nvec = irq_calc_affinity_vectors(minvec, nvec, affd); + if (nvec < minvec) + return -ENOSPC; + } + + rc = __pci_enable_msix(dev, entries, nvec, affd, flags); + if (rc == 0) + return nvec; + + if (rc < 0) + return rc; + if (rc < minvec) + return -ENOSPC; + + nvec = rc; + } +} + +/** + * 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, + int minvec, int maxvec) +{ + return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL, 0); +} +EXPORT_SYMBOL(pci_enable_msix_range); + +/** + * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device + * @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 + * @affd: optional description of the affinity requirements + * + * 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. + */ +int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs, + unsigned int max_vecs, unsigned int flags, + struct irq_affinity *affd) +{ + struct irq_affinity msi_default_affd = {0}; + int nvecs = -ENOSPC; + + if (flags & PCI_IRQ_AFFINITY) { + if (!affd) + affd = &msi_default_affd; + } else { + if (WARN_ON(affd)) + affd = NULL; + } + + if (flags & PCI_IRQ_MSIX) { + nvecs = __pci_enable_msix_range(dev, NULL, min_vecs, max_vecs, + affd, flags); + if (nvecs > 0) + return nvecs; + } + + if (flags & PCI_IRQ_MSI) { + nvecs = __pci_enable_msi_range(dev, min_vecs, max_vecs, affd); + if (nvecs > 0) + return nvecs; + } + + /* use legacy IRQ if allowed */ + if (flags & PCI_IRQ_LEGACY) { + if (min_vecs == 1 && dev->irq) { + /* + * Invoke the affinity spreading logic to ensure that + * the device driver can adjust queue configuration + * for the single interrupt case. + */ + if (affd) + irq_create_affinity_masks(1, affd); + pci_intx(dev, 1); + return 1; + } + } + + return nvecs; +} +EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity); + +/** + * 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: Interrupt vector index (0-based) + * + * @nr has the following meanings depending on the interrupt mode: + * MSI-X: The index in the MSI-X vector table + * MSI: The index of the enabled MSI vectors + * INTx: Must be 0 + * + * Return: The Linux interrupt number or -EINVAl if @nr is out of range. + */ +int pci_irq_vector(struct pci_dev *dev, unsigned int nr) +{ + if (dev->msix_enabled) { + struct msi_desc *entry; + + for_each_pci_msi_entry(entry, dev) { + if (entry->pci.msi_attrib.entry_nr == nr) + return entry->irq; + } + 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); + +/** + * 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). + * + * @nr has the following meanings depending on the interrupt mode: + * MSI-X: The index in the MSI-X vector table + * MSI: The index of the enabled MSI vectors + * INTx: Must be 0 + * + * Return: A cpumask pointer or NULL if @nr is out of range + */ +const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr) +{ + if (dev->msix_enabled) { + struct msi_desc *entry; + + for_each_pci_msi_entry(entry, dev) { + if (entry->pci.msi_attrib.entry_nr == nr) + return &entry->affinity->mask; + } + WARN_ON_ONCE(1); + return NULL; + } else if (dev->msi_enabled) { + struct msi_desc *entry = first_pci_msi_entry(dev); + + if (WARN_ON_ONCE(!entry || !entry->affinity || + nr >= entry->nvec_used)) + return NULL; + + return &entry->affinity[nr].mask; + } else { + return cpu_possible_mask; + } +} +EXPORT_SYMBOL(pci_irq_get_affinity); + +struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc) +{ + return to_pci_dev(desc->dev); +} +EXPORT_SYMBOL(msi_desc_to_pci_dev); + +#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 + */ +static void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg) +{ + struct msi_desc *desc = irq_data_get_msi_desc(irq_data); + + /* + * 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 + * @desc: Pointer to the MSI descriptor + * + * The ID number is only used within the irqdomain. + */ +static irq_hw_number_t pci_msi_domain_calc_hwirq(struct msi_desc *desc) +{ + struct pci_dev *dev = msi_desc_to_pci_dev(desc); + + return (irq_hw_number_t)desc->pci.msi_attrib.entry_nr | + pci_dev_id(dev) << 11 | + (pci_domain_nr(dev->bus) & 0xFFFFFFFF) << 27; +} + +static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc) +{ + return !desc->pci.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)); + + /* Special handling to support __pci_enable_msi_range() */ + if (pci_msi_desc_is_multi_msi(desc) && + !(info->flags & MSI_FLAG_MULTI_PCI_MSI)) + return 1; + else if (desc->pci.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) +{ + /* Special handling to support __pci_enable_msi_range() */ + if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC) + return 1; + + return error; +} + +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(desc); +} + +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; + if (!chip->irq_mask) + chip->irq_mask = pci_msi_mask_irq; + if (!chip->irq_unmask) + chip->irq_unmask = pci_msi_unmask_irq; +} + +/** + * pci_msi_create_irq_domain - Create a MSI interrupt domain + * @fwnode: Optional fwnode of the interrupt controller + * @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. + */ +struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode, + struct msi_domain_info *info, + struct irq_domain *parent) +{ + struct irq_domain *domain; + + if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE)) + info->flags &= ~MSI_FLAG_LEVEL_CAPABLE; + + 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); + + info->flags |= MSI_FLAG_ACTIVATE_EARLY; + if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE)) + info->flags |= MSI_FLAG_MUST_REACTIVATE; + + /* PCI-MSI is oneshot-safe */ + info->chip->flags |= IRQCHIP_ONESHOT_SAFE; + + domain = msi_create_irq_domain(fwnode, info, parent); + if (!domain) + return NULL; + + irq_domain_update_bus_token(domain, DOMAIN_BUS_PCI_MSI); + return domain; +} +EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain); + +/* + * 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... + */ +static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data) +{ + u32 *pa = data; + u8 bus = PCI_BUS_NUM(*pa); + + if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus) + *pa = alias; + + return 0; +} + +/** + * 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; + u32 rid = pci_dev_id(pdev); + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + + of_node = irq_domain_get_of_node(domain); + rid = of_node ? of_msi_map_id(&pdev->dev, of_node, rid) : + iort_msi_map_id(&pdev->dev, rid); + + return rid; +} + +/** + * 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 + * (i.e. not one that is set as a default). + * + * Returns: The corresponding MSI domain or NULL if none has been found. + */ +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + struct irq_domain *dom; + u32 rid = pci_dev_id(pdev); + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + dom = of_msi_map_get_device_domain(&pdev->dev, rid, DOMAIN_BUS_PCI_MSI); + if (!dom) + dom = iort_get_device_domain(&pdev->dev, rid, + DOMAIN_BUS_PCI_MSI); + return dom; +} + +/** + * pci_dev_has_special_msi_domain - Check whether the device is handled by + * a non-standard PCI-MSI domain + * @pdev: The PCI device to check. + * + * Returns: True if the device irqdomain or the bus irqdomain is + * non-standard PCI/MSI. + */ +bool pci_dev_has_special_msi_domain(struct pci_dev *pdev) +{ + struct irq_domain *dom = dev_get_msi_domain(&pdev->dev); + + if (!dom) + dom = dev_get_msi_domain(&pdev->bus->dev); + + if (!dom) + return true; + + return dom->bus_token != DOMAIN_BUS_PCI_MSI; +} + +#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ +#endif /* CONFIG_PCI_MSI */ + +void pci_msi_init(struct pci_dev *dev) +{ + u16 ctrl; + + /* + * Disable the MSI hardware to avoid screaming interrupts + * during boot. This is the power on reset default so + * usually this should be a noop. + */ + dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI); + if (!dev->msi_cap) + return; + + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl); + if (ctrl & PCI_MSI_FLAGS_ENABLE) + pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, + ctrl & ~PCI_MSI_FLAGS_ENABLE); + + if (!(ctrl & PCI_MSI_FLAGS_64BIT)) + dev->no_64bit_msi = 1; +} + +void pci_msix_init(struct pci_dev *dev) +{ + u16 ctrl; + + dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX); + if (!dev->msix_cap) + return; + + pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl); + if (ctrl & PCI_MSIX_FLAGS_ENABLE) + pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, + ctrl & ~PCI_MSIX_FLAGS_ENABLE); +}
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