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Merge branch 'pci/host-vmd' into next

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* pci/host-vmd:
  x86/PCI: VMD: Move VMD driver to drivers/pci/host
  x86/PCI: VMD: Synchronize with RCU freeing MSI IRQ descs
  x86/PCI: VMD: Eliminate index member from IRQ list
  x86/PCI: VMD: Eliminate vmd_vector member from list type
  x86/PCI: VMD: Convert to use pci_alloc_irq_vectors() API
  x86/PCI: VMD: Allocate IRQ lists with correct MSI-X count
  PCI: Use positive flags in pci_alloc_irq_vectors()
  PCI: Update "pci=resource_alignment" documentation

Conflicts:
	drivers/pci/host/Kconfig
	drivers/pci/host/Makefile
This commit is contained in:
Bjorn Helgaas
2016-10-05 14:00:21 -05:00
parent 69a06e4984 181ffd19cc
commit bdf530984d
9 changed files with 66 additions and 67 deletions
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24
Documentation/PCI/MSI-HOWTO.txt
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@@ -94,14 +94,11 @@ has a requirements for a minimum number of vectors the driver can pass a
min_vecs argument set to this limit, and the PCI core will return -ENOSPC
if it can't meet the minimum number of vectors.
The flags argument should normally be set to 0, but can be used to pass the
PCI_IRQ_NOMSI and PCI_IRQ_NOMSIX flag in case a device claims to support
MSI or MSI-X, but the support is broken, or to pass PCI_IRQ_NOLEGACY in
case the device does not support legacy interrupt lines.
By default this function will spread the interrupts around the available
CPUs, but this feature can be disabled by passing the PCI_IRQ_NOAFFINITY
flag.
The flags argument is used to specify which type of interrupt can be used
by the device and the driver (PCI_IRQ_LEGACY, PCI_IRQ_MSI, PCI_IRQ_MSIX).
A convenient short-hand (PCI_IRQ_ALL_TYPES) is also available to ask for
any possible kind of interrupt. If the PCI_IRQ_AFFINITY flag is set,
pci_alloc_irq_vectors() will spread the interrupts around the available CPUs.
To get the Linux IRQ numbers passed to request_irq() and free_irq() and the
vectors, use the following function:
@@ -131,7 +128,7 @@ larger than the number supported by the device it will automatically be
capped to the supported limit, so there is no need to query the number of
vectors supported beforehand:
nvec = pci_alloc_irq_vectors(pdev, 1, nvec, 0);
nvec = pci_alloc_irq_vectors(pdev, 1, nvec, PCI_IRQ_ALL_TYPES)
if (nvec < 0)
goto out_err;
@@ -140,7 +137,7 @@ interrupts it can request a particular number of interrupts by passing that
number to pci_alloc_irq_vectors() function as both 'min_vecs' and
'max_vecs' parameters:
ret = pci_alloc_irq_vectors(pdev, nvec, nvec, 0);
ret = pci_alloc_irq_vectors(pdev, nvec, nvec, PCI_IRQ_ALL_TYPES);
if (ret < 0)
goto out_err;
@@ -148,15 +145,14 @@ The most notorious example of the request type described above is enabling
the single MSI mode for a device. It could be done by passing two 1s as
'min_vecs' and 'max_vecs':
ret = pci_alloc_irq_vectors(pdev, 1, 1, 0);
ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
if (ret < 0)
goto out_err;
Some devices might not support using legacy line interrupts, in which case
the PCI_IRQ_NOLEGACY flag can be used to fail the request if the platform
can't provide MSI or MSI-X interrupts:
the driver can specify that only MSI or MSI-X is acceptable:
nvec = pci_alloc_irq_vectors(pdev, 1, nvec, PCI_IRQ_NOLEGACY);
nvec = pci_alloc_irq_vectors(pdev, 1, nvec, PCI_IRQ_MSI | PCI_IRQ_MSIX);
if (nvec < 0)
goto out_err;