![Yijing Wang](/assets/img/avatar_default.png)
Use irq_get_msi_desc() to get MSI IRQ related msi_desc directly instead of searching the dev->msi_list. Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
1152 lines
28 KiB
C
1152 lines
28 KiB
C
/*
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* File: msi.c
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* Purpose: PCI Message Signaled Interrupt (MSI)
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*
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* Copyright (C) 2003-2004 Intel
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* Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
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*/
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#include <linux/err.h>
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#include <linux/mm.h>
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#include <linux/irq.h>
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#include <linux/interrupt.h>
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#include <linux/export.h>
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#include <linux/ioport.h>
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#include <linux/pci.h>
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#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>
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#include <linux/io.h>
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#include <linux/slab.h>
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#include "pci.h"
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static int pci_msi_enable = 1;
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#define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
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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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{
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struct msi_chip *chip = dev->bus->msi;
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int err;
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if (!chip || !chip->setup_irq)
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return -EINVAL;
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err = chip->setup_irq(chip, dev, desc);
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if (err < 0)
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return err;
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irq_set_chip_data(desc->irq, chip);
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return 0;
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}
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void __weak arch_teardown_msi_irq(unsigned int irq)
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{
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struct msi_chip *chip = irq_get_chip_data(irq);
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if (!chip || !chip->teardown_irq)
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return;
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chip->teardown_irq(chip, irq);
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}
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int __weak arch_msi_check_device(struct pci_dev *dev, int nvec, int type)
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{
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struct msi_chip *chip = dev->bus->msi;
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if (!chip || !chip->check_device)
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return 0;
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return chip->check_device(chip, dev, nvec, type);
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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_desc *entry;
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int ret;
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/*
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* If an architecture wants to support multiple MSI, it needs to
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* override arch_setup_msi_irqs()
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*/
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if (type == PCI_CAP_ID_MSI && nvec > 1)
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return 1;
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list_for_each_entry(entry, &dev->msi_list, list) {
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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)
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return -ENOSPC;
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}
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return 0;
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}
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/*
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* We have a default implementation available as a separate non-weak
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* function, as it is used by the Xen x86 PCI code
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*/
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void default_teardown_msi_irqs(struct pci_dev *dev)
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{
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struct msi_desc *entry;
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list_for_each_entry(entry, &dev->msi_list, list) {
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int i, nvec;
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if (entry->irq == 0)
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continue;
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if (entry->nvec_used)
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nvec = entry->nvec_used;
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else
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nvec = 1 << entry->msi_attrib.multiple;
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for (i = 0; i < nvec; i++)
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arch_teardown_msi_irq(entry->irq + i);
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}
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}
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void __weak arch_teardown_msi_irqs(struct pci_dev *dev)
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{
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return default_teardown_msi_irqs(dev);
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}
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static void default_restore_msi_irq(struct pci_dev *dev, int irq)
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{
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struct msi_desc *entry;
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entry = NULL;
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if (dev->msix_enabled) {
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list_for_each_entry(entry, &dev->msi_list, list) {
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if (irq == entry->irq)
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break;
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}
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} else if (dev->msi_enabled) {
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entry = irq_get_msi_desc(irq);
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}
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if (entry)
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write_msi_msg(irq, &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 void msi_set_enable(struct pci_dev *dev, int enable)
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{
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u16 control;
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pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
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control &= ~PCI_MSI_FLAGS_ENABLE;
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if (enable)
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control |= PCI_MSI_FLAGS_ENABLE;
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pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
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}
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static void msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
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{
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u16 ctrl;
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pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
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ctrl &= ~clear;
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ctrl |= set;
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pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
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}
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static inline __attribute_const__ u32 msi_mask(unsigned x)
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{
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/* Don't shift by >= width of type */
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if (x >= 5)
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return 0xffffffff;
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return (1 << (1 << x)) - 1;
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}
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/*
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* PCI 2.3 does not specify mask bits for each MSI interrupt. Attempting to
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* mask all MSI interrupts by clearing the MSI enable bit does not work
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* reliably as devices without an INTx disable bit will then generate a
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* level IRQ which will never be cleared.
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*/
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u32 default_msi_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 (!desc->msi_attrib.maskbit)
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return 0;
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mask_bits &= ~mask;
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mask_bits |= flag;
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pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits);
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return mask_bits;
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}
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__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
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{
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return default_msi_mask_irq(desc, mask, flag);
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}
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static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
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{
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desc->masked = arch_msi_mask_irq(desc, mask, flag);
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}
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/*
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* This internal function does not flush PCI writes to the device.
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* All users must ensure that they read from the device before either
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* assuming that the device state is up to date, or returning out of this
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* file. This saves a few milliseconds when initialising devices with lots
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* of MSI-X interrupts.
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*/
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u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
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{
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u32 mask_bits = desc->masked;
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unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
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PCI_MSIX_ENTRY_VECTOR_CTRL;
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mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
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if (flag)
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mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
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writel(mask_bits, desc->mask_base + offset);
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return mask_bits;
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}
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__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag)
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{
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return default_msix_mask_irq(desc, flag);
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}
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static void msix_mask_irq(struct msi_desc *desc, u32 flag)
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{
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desc->masked = arch_msix_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(data);
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if (desc->msi_attrib.is_msix) {
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msix_mask_irq(desc, flag);
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readl(desc->mask_base); /* Flush write to device */
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} 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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void mask_msi_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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void unmask_msi_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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void default_restore_msi_irqs(struct pci_dev *dev)
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{
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struct msi_desc *entry;
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list_for_each_entry(entry, &dev->msi_list, list) {
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default_restore_msi_irq(dev, entry->irq);
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}
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}
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void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
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{
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BUG_ON(entry->dev->current_state != PCI_D0);
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if (entry->msi_attrib.is_msix) {
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void __iomem *base = entry->mask_base +
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entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
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msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
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msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
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msg->data = readl(base + PCI_MSIX_ENTRY_DATA);
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} else {
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struct pci_dev *dev = entry->dev;
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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,
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&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,
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&msg->address_hi);
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pci_read_config_word(dev, pos + PCI_MSI_DATA_64, &data);
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} else {
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msg->address_hi = 0;
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pci_read_config_word(dev, pos + PCI_MSI_DATA_32, &data);
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}
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msg->data = data;
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}
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}
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void read_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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__read_msi_msg(entry, msg);
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}
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void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
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{
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/* Assert that the cache is valid, assuming that
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* valid messages are not all-zeroes. */
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BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo |
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entry->msg.data));
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*msg = entry->msg;
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}
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void get_cached_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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__get_cached_msi_msg(entry, msg);
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}
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void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
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{
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if (entry->dev->current_state != PCI_D0) {
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/* Don't touch the hardware now */
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} else if (entry->msi_attrib.is_msix) {
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void __iomem *base;
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base = entry->mask_base +
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entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
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writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
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writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
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writel(msg->data, base + PCI_MSIX_ENTRY_DATA);
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} else {
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struct pci_dev *dev = entry->dev;
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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;
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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,
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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,
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msg->address_hi);
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pci_write_config_word(dev, pos + PCI_MSI_DATA_64,
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msg->data);
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} else {
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pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
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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 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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__write_msi_msg(entry, msg);
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}
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static void free_msi_irqs(struct pci_dev *dev)
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{
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struct msi_desc *entry, *tmp;
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struct attribute **msi_attrs;
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struct device_attribute *dev_attr;
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int count = 0;
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list_for_each_entry(entry, &dev->msi_list, list) {
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int i, nvec;
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if (!entry->irq)
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continue;
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if (entry->nvec_used)
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nvec = entry->nvec_used;
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else
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nvec = 1 << entry->msi_attrib.multiple;
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for (i = 0; i < nvec; i++)
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BUG_ON(irq_has_action(entry->irq + i));
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}
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arch_teardown_msi_irqs(dev);
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list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
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if (entry->msi_attrib.is_msix) {
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if (list_is_last(&entry->list, &dev->msi_list))
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iounmap(entry->mask_base);
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}
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/*
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* Its possible that we get into this path
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* When populate_msi_sysfs fails, which means the entries
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* were not registered with sysfs. In that case don't
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* unregister them.
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*/
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if (entry->kobj.parent) {
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kobject_del(&entry->kobj);
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kobject_put(&entry->kobj);
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}
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list_del(&entry->list);
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kfree(entry);
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}
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if (dev->msi_irq_groups) {
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sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);
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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],
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struct device_attribute, attr);
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kfree(dev_attr->attr.name);
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kfree(dev_attr);
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++count;
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}
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kfree(msi_attrs);
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kfree(dev->msi_irq_groups[0]);
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kfree(dev->msi_irq_groups);
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dev->msi_irq_groups = NULL;
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}
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}
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static struct msi_desc *alloc_msi_entry(struct pci_dev *dev)
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{
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struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
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if (!desc)
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return NULL;
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INIT_LIST_HEAD(&desc->list);
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desc->dev = dev;
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return desc;
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}
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static void pci_intx_for_msi(struct pci_dev *dev, int enable)
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{
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if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG))
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pci_intx(dev, enable);
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}
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static void __pci_restore_msi_state(struct pci_dev *dev)
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{
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u16 control;
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struct msi_desc *entry;
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if (!dev->msi_enabled)
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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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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),
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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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}
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static void __pci_restore_msix_state(struct pci_dev *dev)
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{
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struct msi_desc *entry;
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if (!dev->msix_enabled)
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return;
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BUG_ON(list_empty(&dev->msi_list));
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/* route the table */
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pci_intx_for_msi(dev, 0);
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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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list_for_each_entry(entry, &dev->msi_list, list) {
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msix_mask_irq(entry, entry->masked);
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}
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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)
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{
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__pci_restore_msi_state(dev);
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__pci_restore_msix_state(dev);
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}
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EXPORT_SYMBOL_GPL(pci_restore_msi_state);
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static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
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char *buf)
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{
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struct msi_desc *entry;
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unsigned long irq;
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int retval;
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retval = kstrtoul(attr->attr.name, 10, &irq);
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if (retval)
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return retval;
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entry = irq_get_msi_desc(irq);
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if (entry)
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return sprintf(buf, "%s\n",
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entry->msi_attrib.is_msix ? "msix" : "msi");
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return -ENODEV;
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}
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|
|
static int populate_msi_sysfs(struct pci_dev *pdev)
|
|
{
|
|
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;
|
|
struct msi_desc *entry;
|
|
int ret = -ENOMEM;
|
|
int num_msi = 0;
|
|
int count = 0;
|
|
|
|
/* Determine how many msi entries we have */
|
|
list_for_each_entry(entry, &pdev->msi_list, list) {
|
|
++num_msi;
|
|
}
|
|
if (!num_msi)
|
|
return 0;
|
|
|
|
/* Dynamically create the MSI attributes for the PCI device */
|
|
msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL);
|
|
if (!msi_attrs)
|
|
return -ENOMEM;
|
|
list_for_each_entry(entry, &pdev->msi_list, list) {
|
|
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);
|
|
if (!msi_dev_attr->attr.name)
|
|
goto error_attrs;
|
|
msi_dev_attr->attr.mode = S_IRUGO;
|
|
msi_dev_attr->show = msi_mode_show;
|
|
++count;
|
|
}
|
|
|
|
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;
|
|
|
|
msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL);
|
|
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;
|
|
|
|
return 0;
|
|
|
|
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];
|
|
}
|
|
kfree(msi_attrs);
|
|
return ret;
|
|
}
|
|
|
|
static struct msi_desc *msi_setup_entry(struct pci_dev *dev)
|
|
{
|
|
u16 control;
|
|
struct msi_desc *entry;
|
|
|
|
/* MSI Entry Initialization */
|
|
entry = alloc_msi_entry(dev);
|
|
if (!entry)
|
|
return NULL;
|
|
|
|
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.pos = dev->msi_cap;
|
|
entry->msi_attrib.multi_cap = (control & PCI_MSI_FLAGS_QMASK) >> 1;
|
|
|
|
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);
|
|
|
|
return entry;
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
*
|
|
* 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 msi_desc *entry;
|
|
int ret;
|
|
unsigned mask;
|
|
|
|
msi_set_enable(dev, 0); /* Disable MSI during set up */
|
|
|
|
entry = msi_setup_entry(dev);
|
|
if (!entry)
|
|
return -ENOMEM;
|
|
|
|
/* All MSIs are unmasked by default, Mask them all */
|
|
mask = msi_mask(entry->msi_attrib.multi_cap);
|
|
msi_mask_irq(entry, mask, mask);
|
|
|
|
list_add_tail(&entry->list, &dev->msi_list);
|
|
|
|
/* Configure MSI capability structure */
|
|
ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);
|
|
if (ret) {
|
|
msi_mask_irq(entry, mask, ~mask);
|
|
free_msi_irqs(dev);
|
|
return ret;
|
|
}
|
|
|
|
ret = populate_msi_sysfs(dev);
|
|
if (ret) {
|
|
msi_mask_irq(entry, mask, ~mask);
|
|
free_msi_irqs(dev);
|
|
return ret;
|
|
}
|
|
|
|
/* Set MSI enabled bits */
|
|
pci_intx_for_msi(dev, 0);
|
|
msi_set_enable(dev, 1);
|
|
dev->msi_enabled = 1;
|
|
|
|
dev->irq = entry->irq;
|
|
return 0;
|
|
}
|
|
|
|
static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
|
|
{
|
|
resource_size_t phys_addr;
|
|
u32 table_offset;
|
|
u8 bir;
|
|
|
|
pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE,
|
|
&table_offset);
|
|
bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
|
|
table_offset &= PCI_MSIX_TABLE_OFFSET;
|
|
phys_addr = pci_resource_start(dev, bir) + table_offset;
|
|
|
|
return ioremap_nocache(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 msi_desc *entry;
|
|
int i;
|
|
|
|
for (i = 0; i < nvec; i++) {
|
|
entry = alloc_msi_entry(dev);
|
|
if (!entry) {
|
|
if (!i)
|
|
iounmap(base);
|
|
else
|
|
free_msi_irqs(dev);
|
|
/* No enough memory. Don't try again */
|
|
return -ENOMEM;
|
|
}
|
|
|
|
entry->msi_attrib.is_msix = 1;
|
|
entry->msi_attrib.is_64 = 1;
|
|
entry->msi_attrib.entry_nr = entries[i].entry;
|
|
entry->msi_attrib.default_irq = dev->irq;
|
|
entry->msi_attrib.pos = dev->msix_cap;
|
|
entry->mask_base = base;
|
|
|
|
list_add_tail(&entry->list, &dev->msi_list);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void msix_program_entries(struct pci_dev *dev,
|
|
struct msix_entry *entries)
|
|
{
|
|
struct msi_desc *entry;
|
|
int i = 0;
|
|
|
|
list_for_each_entry(entry, &dev->msi_list, list) {
|
|
int offset = entries[i].entry * PCI_MSIX_ENTRY_SIZE +
|
|
PCI_MSIX_ENTRY_VECTOR_CTRL;
|
|
|
|
entries[i].vector = entry->irq;
|
|
irq_set_msi_desc(entry->irq, entry);
|
|
entry->masked = readl(entry->mask_base + offset);
|
|
msix_mask_irq(entry, 1);
|
|
i++;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
*
|
|
* 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)
|
|
{
|
|
int ret;
|
|
u16 control;
|
|
void __iomem *base;
|
|
|
|
/* Ensure MSI-X is disabled while it is set up */
|
|
msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
|
|
|
|
pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);
|
|
/* Request & Map MSI-X table region */
|
|
base = msix_map_region(dev, msix_table_size(control));
|
|
if (!base)
|
|
return -ENOMEM;
|
|
|
|
ret = msix_setup_entries(dev, base, entries, nvec);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
|
|
if (ret)
|
|
goto out_avail;
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
msix_clear_and_set_ctrl(dev, 0,
|
|
PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
|
|
|
|
msix_program_entries(dev, entries);
|
|
|
|
ret = populate_msi_sysfs(dev);
|
|
if (ret)
|
|
goto out_free;
|
|
|
|
/* Set MSI-X enabled bits and unmask the function */
|
|
pci_intx_for_msi(dev, 0);
|
|
dev->msix_enabled = 1;
|
|
|
|
msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
|
|
|
|
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;
|
|
|
|
list_for_each_entry(entry, &dev->msi_list, list) {
|
|
if (entry->irq != 0)
|
|
avail++;
|
|
}
|
|
if (avail != 0)
|
|
ret = avail;
|
|
}
|
|
|
|
out_free:
|
|
free_msi_irqs(dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* pci_msi_check_device - 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 ?
|
|
* @type: are we checking for MSI or MSI-X ?
|
|
*
|
|
* 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 0, else return an error code.
|
|
**/
|
|
static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
|
|
{
|
|
struct pci_bus *bus;
|
|
int ret;
|
|
|
|
/* MSI must be globally enabled and supported by the device */
|
|
if (!pci_msi_enable || !dev || dev->no_msi)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* 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 -ERANGE;
|
|
|
|
/*
|
|
* 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.
|
|
* We expect only arch-specific PCI host bus controller driver
|
|
* or quirks for specific PCI bridges to be setting NO_MSI.
|
|
*/
|
|
for (bus = dev->bus; bus; bus = bus->parent)
|
|
if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
|
|
return -EINVAL;
|
|
|
|
ret = arch_msi_check_device(dev, nvec, type);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* 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);
|
|
|
|
void pci_msi_shutdown(struct pci_dev *dev)
|
|
{
|
|
struct msi_desc *desc;
|
|
u32 mask;
|
|
|
|
if (!pci_msi_enable || !dev || !dev->msi_enabled)
|
|
return;
|
|
|
|
BUG_ON(list_empty(&dev->msi_list));
|
|
desc = list_first_entry(&dev->msi_list, struct msi_desc, list);
|
|
|
|
msi_set_enable(dev, 0);
|
|
pci_intx_for_msi(dev, 1);
|
|
dev->msi_enabled = 0;
|
|
|
|
/* Return the device with MSI unmasked as initial states */
|
|
mask = msi_mask(desc->msi_attrib.multi_cap);
|
|
/* Keep cached state to be restored */
|
|
arch_msi_mask_irq(desc, mask, ~mask);
|
|
|
|
/* Restore dev->irq to its default pin-assertion irq */
|
|
dev->irq = desc->msi_attrib.default_irq;
|
|
}
|
|
|
|
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);
|
|
|
|
/**
|
|
* pci_enable_msix - 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
|
|
* @nvec: number of MSI-X irqs requested for allocation by device driver
|
|
*
|
|
* Setup the MSI-X capability structure of device function with the number
|
|
* of requested irqs upon its software driver call to request for
|
|
* MSI-X mode enabled on its hardware device function. A return of zero
|
|
* indicates the successful configuration of MSI-X capability structure
|
|
* with new allocated MSI-X irqs. A return of < 0 indicates a failure.
|
|
* Or a return of > 0 indicates that driver request is exceeding the number
|
|
* of irqs or MSI-X vectors available. Driver should use the returned value to
|
|
* re-send its request.
|
|
**/
|
|
int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec)
|
|
{
|
|
int status, nr_entries;
|
|
int i, j;
|
|
|
|
if (!entries || !dev->msix_cap || dev->current_state != PCI_D0)
|
|
return -EINVAL;
|
|
|
|
status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX);
|
|
if (status)
|
|
return status;
|
|
|
|
nr_entries = pci_msix_vec_count(dev);
|
|
if (nr_entries < 0)
|
|
return nr_entries;
|
|
if (nvec > nr_entries)
|
|
return nr_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 */
|
|
}
|
|
}
|
|
WARN_ON(!!dev->msix_enabled);
|
|
|
|
/* Check whether driver already requested for MSI irq */
|
|
if (dev->msi_enabled) {
|
|
dev_info(&dev->dev, "can't enable MSI-X (MSI IRQ already assigned)\n");
|
|
return -EINVAL;
|
|
}
|
|
status = msix_capability_init(dev, entries, nvec);
|
|
return status;
|
|
}
|
|
EXPORT_SYMBOL(pci_enable_msix);
|
|
|
|
void pci_msix_shutdown(struct pci_dev *dev)
|
|
{
|
|
struct msi_desc *entry;
|
|
|
|
if (!pci_msi_enable || !dev || !dev->msix_enabled)
|
|
return;
|
|
|
|
/* Return the device with MSI-X masked as initial states */
|
|
list_for_each_entry(entry, &dev->msi_list, list) {
|
|
/* Keep cached states to be restored */
|
|
arch_msix_mask_irq(entry, 1);
|
|
}
|
|
|
|
msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
|
|
pci_intx_for_msi(dev, 1);
|
|
dev->msix_enabled = 0;
|
|
}
|
|
|
|
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);
|
|
|
|
void pci_msi_init_pci_dev(struct pci_dev *dev)
|
|
{
|
|
INIT_LIST_HEAD(&dev->msi_list);
|
|
|
|
/* 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)
|
|
msi_set_enable(dev, 0);
|
|
|
|
dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
|
|
if (dev->msix_cap)
|
|
msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
|
|
}
|
|
|
|
/**
|
|
* pci_enable_msi_range - configure device's MSI capability structure
|
|
* @dev: device to configure
|
|
* @minvec: minimal number of interrupts to configure
|
|
* @maxvec: maximum number of interrupts to configure
|
|
*
|
|
* This function tries to allocate a maximum possible number of interrupts in a
|
|
* range between @minvec and @maxvec. It returns a negative errno if an error
|
|
* occurs. If it succeeds, it returns the actual number of interrupts allocated
|
|
* and updates the @dev's irq member to the lowest new interrupt number;
|
|
* the other interrupt numbers allocated to this device are consecutive.
|
|
**/
|
|
int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec)
|
|
{
|
|
int nvec;
|
|
int rc;
|
|
|
|
if (dev->current_state != PCI_D0)
|
|
return -EINVAL;
|
|
|
|
WARN_ON(!!dev->msi_enabled);
|
|
|
|
/* Check whether driver already requested MSI-X irqs */
|
|
if (dev->msix_enabled) {
|
|
dev_info(&dev->dev,
|
|
"can't enable MSI (MSI-X already enabled)\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (maxvec < minvec)
|
|
return -ERANGE;
|
|
|
|
nvec = pci_msi_vec_count(dev);
|
|
if (nvec < 0)
|
|
return nvec;
|
|
else if (nvec < minvec)
|
|
return -EINVAL;
|
|
else if (nvec > maxvec)
|
|
nvec = maxvec;
|
|
|
|
do {
|
|
rc = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI);
|
|
if (rc < 0) {
|
|
return rc;
|
|
} else if (rc > 0) {
|
|
if (rc < minvec)
|
|
return -ENOSPC;
|
|
nvec = rc;
|
|
}
|
|
} while (rc);
|
|
|
|
do {
|
|
rc = msi_capability_init(dev, nvec);
|
|
if (rc < 0) {
|
|
return rc;
|
|
} else if (rc > 0) {
|
|
if (rc < minvec)
|
|
return -ENOSPC;
|
|
nvec = rc;
|
|
}
|
|
} while (rc);
|
|
|
|
return nvec;
|
|
}
|
|
EXPORT_SYMBOL(pci_enable_msi_range);
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
int nvec = maxvec;
|
|
int rc;
|
|
|
|
if (maxvec < minvec)
|
|
return -ERANGE;
|
|
|
|
do {
|
|
rc = pci_enable_msix(dev, entries, nvec);
|
|
if (rc < 0) {
|
|
return rc;
|
|
} else if (rc > 0) {
|
|
if (rc < minvec)
|
|
return -ENOSPC;
|
|
nvec = rc;
|
|
}
|
|
} while (rc);
|
|
|
|
return nvec;
|
|
}
|
|
EXPORT_SYMBOL(pci_enable_msix_range);
|