drivers/pci/irq.c

   1 /*
   2  * PCI IRQ failure handing code
   3  *
   4  * Copyright (c) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
   5  */
   6
   7 #include <linux/acpi.h>
   8 #include <linux/device.h>
   9 #include <linux/kernel.h>
  10 #include <linux/export.h>
  11 #include <linux/pci.h>
  12
  13 static void pci_note_irq_problem(struct pci_dev *pdev, const char *reason)
  14 {
  15         struct pci_dev *parent = to_pci_dev(pdev->dev.parent);
  16
  17         dev_printk(KERN_ERR, &pdev->dev,
  18                    "Potentially misrouted IRQ (Bridge %s %04x:%04x)\n",
  19                    dev_name(&parent->dev), parent->vendor, parent->device);
  20         dev_printk(KERN_ERR, &pdev->dev, "%s\n", reason);
  21         dev_printk(KERN_ERR, &pdev->dev, "Please report to linux-kernel@vger.kernel.org\n");
  22         WARN_ON(1);
  23 }
  24
  25 /**
  26  * pci_lost_interrupt - reports a lost PCI interrupt
  27  * @pdev:       device whose interrupt is lost
  28  *
  29  * The primary function of this routine is to report a lost interrupt
  30  * in a standard way which users can recognise (instead of blaming the
  31  * driver).
  32  *
  33  * Returns:
  34  *  a suggestion for fixing it (although the driver is not required to
  35  * act on this).
  36  */
  37 enum pci_lost_interrupt_reason pci_lost_interrupt(struct pci_dev *pdev)
  38 {
  39         if (pdev->msi_enabled || pdev->msix_enabled) {
  40                 enum pci_lost_interrupt_reason ret;
  41
  42                 if (pdev->msix_enabled) {
  43                         pci_note_irq_problem(pdev, "MSIX routing failure");
  44                         ret = PCI_LOST_IRQ_DISABLE_MSIX;
  45                 } else {
  46                         pci_note_irq_problem(pdev, "MSI routing failure");
  47                         ret = PCI_LOST_IRQ_DISABLE_MSI;
  48                 }
  49                 return ret;
  50         }
  51 #ifdef CONFIG_ACPI
  52         if (!(acpi_disabled || acpi_noirq)) {
  53                 pci_note_irq_problem(pdev, "Potential ACPI misrouting please reboot with acpi=noirq");
  54                 /* currently no way to fix acpi on the fly */
  55                 return PCI_LOST_IRQ_DISABLE_ACPI;
  56         }
  57 #endif
  58         pci_note_irq_problem(pdev, "unknown cause (not MSI or ACPI)");
  59         return PCI_LOST_IRQ_NO_INFORMATION;
  60 }
  61 EXPORT_SYMBOL(pci_lost_interrupt);