Commit 5a1e0baa authored Mar 13, 2018 by Bjorn Helgaas

PCI/MSI: Don't set up INTx if MSI or MSI-X is enabled



If MSI or MSI-X is enabled, the device uses that.  It uses INTx only if
both MSI and MSI-X are disabled (see PCIe r4.0, sec 7.7.1.2), so if a
device already has MSI or MSI-X enabled, there's no need to set up its
legacy INTx interrupt.

bba6f6fc ("[PATCH] MSI-X: fix resume crash") changed the cris, frv,
x86, and ia64 arches to skip INTx setup when MSI is enabled.  The cris and
frv arches have since been removed.

16cf0ebc ("x86/PCI: Do not use interrupt links for devices using
MSI-X") extended that by changing x86 to also skip INTx setup when MSI-X is
enabled.

Change ia64 to skip INTx setup when either MSI or MSI-X is enabled by
applying the logic from 16cf0ebc to ia64 as well as x86.

Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

parent 7928b2cb

arch/ia64/pci/pci.c

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -398,7 +398,7 @@ pcibios_enable_device (struct pci_dev *dev, int mask)
	if (ret < 0)		if (ret < 0)
	return ret;		return ret;

	if (!dev->msi_enabled)		if (!pci_dev_msi_enabled(dev))
	return acpi_pci_irq_enable(dev);		return acpi_pci_irq_enable(dev);
	return 0;		return 0;
	}		}
	@@ -407,7 +407,7 @@ void
	pcibios_disable_device (struct pci_dev *dev)		pcibios_disable_device (struct pci_dev *dev)
	{		{
	BUG_ON(atomic_read(&dev->enable_cnt));		BUG_ON(atomic_read(&dev->enable_cnt));
	if (!dev->msi_enabled)		if (!pci_dev_msi_enabled(dev))
	acpi_pci_irq_disable(dev);		acpi_pci_irq_disable(dev);
	}		}