linux-toradex.git/drivers/pci/iov.c, branch v5.0

PCI/IOV: Add flag so platforms can skip VF scanning

2019-01-02T01:04:37+00:00

Provide a flag to skip scanning for new VFs after SR-IOV enablement.  This
can be set by implementations for which the VFs are already reported by
other means.

Signed-off-by: Sebastian Ott 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Christoph Hellwig

PCI/IOV: Factor out sriov_add_vfs()

2019-01-02T01:03:51+00:00

Provide sriov_add_vfs() as a wrapper to scan for VFs that cleans up after
itself.  This is just a code simplification.  No functional change.

Signed-off-by: Sebastian Ott 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Christoph Hellwig

PCI/IOV: Remove unnecessary include of

2018-10-11T19:35:12+00:00

iov.c uses nothing declared in , so remove the include of
it.  No functional change intended.

Signed-off-by: Bjorn Helgaas

PCI/IOV: Use VF0 cached config space size for other VFs

2018-10-11T16:49:58+00:00

Cache the config space size from VF0 and use it for all other VFs instead
of reading it from the config space of each VF.  We assume that it will be
the same across all associated VFs.

This is an optimization when enabling SR-IOV on a device with many VFs.

Signed-off-by: KarimAllah Ahmed 
[bhelgaas: use CONFIG_PCI_IOV (not CONFIG_PCI_ATS)]
Signed-off-by: Bjorn Helgaas

Merge branch 'pci/virtualization'

2018-08-15T19:59:06+00:00

  - To avoid bus errors, enable PASID only if entire path supports End-End
    TLP prefixes (Sinan Kaya)

  - Unify slot and bus reset functions and remove hotplug knowledge from
    callers (Sinan Kaya)

  - Add Function-Level Reset quirks for Intel and Samsung NVMe devices to
    fix guest reboot issues (Alex Williamson)

  - Add function 1 DMA alias quirk for Marvell 88SS9183 PCIe SSD Controller
    (Bjorn Helgaas)

* pci/virtualization:
  PCI: Add function 1 DMA alias quirk for Marvell 88SS9183
  PCI: Delay after FLR of Intel DC P3700 NVMe
  PCI: Disable Samsung SM961/PM961 NVMe before FLR
  PCI: Export pcie_has_flr()
  PCI: Rename pci_try_reset_bus() to pci_reset_bus()
  PCI: Deprecate pci_reset_bus() and pci_reset_slot() functions
  PCI: Unify try slot and bus reset API
  PCI: Hide pci_reset_bridge_secondary_bus() from drivers
  IB/hfi1: Use pci_try_reset_bus() for initiating PCI Secondary Bus Reset
  PCI: Handle error return from pci_reset_bridge_secondary_bus()
  PCI/IOV: Tidy pci_sriov_set_totalvfs()
  PCI: Enable PASID only if entire path supports End-End TLP prefixes

# Conflicts:
#	drivers/pci/hotplug/pciehp_hpc.c

PCI/IOV: Tidy pci_sriov_set_totalvfs()

2018-07-19T21:42:21+00:00

Fix minor style issues in pci_sriov_set_totalvfs().  No functional change
intended.

Signed-off-by: Bjorn Helgaas

PCI/IOV: Reset total_VFs limit after detaching PF driver

2018-06-29T20:08:52+00:00

The TotalVFs register in the SR-IOV capability is the hardware limit on the
number of VFs.  A PF driver can limit the number of VFs further with
pci_sriov_set_totalvfs().  When the PF driver is removed, reset any VF
limit that was imposed by the driver because that limit may not apply to
other drivers.

Before 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0"),
pci_sriov_set_totalvfs(pdev, 0) meant "we can enable TotalVFs virtual
functions", and the nfp driver used that to remove the VF limit when the
driver unloads.

8d85a7a4f2c9 broke that because instead of removing the VF limit,
pci_sriov_set_totalvfs(pdev, 0) actually sets the limit to zero, and that
limit persists even if another driver is loaded.

We could fix that by making the nfp driver reset the limit when it unloads,
but it seems more robust to do it in the PCI core instead of relying on the
driver.

The regression scenario is:

  nfp_pci_probe (driver 1)
  ...
  nfp_pci_remove
    pci_sriov_set_totalvfs(pf->pdev, 0)   # limits VFs to 0

  ...
  nfp_pci_probe (driver 2)
    nfp_rtsym_read_le("nfd_vf_cfg_max_vfs")
    # no VF limit from firmware

Now driver 2 is broken because the VF limit is still 0 from driver 1.

Fixes: 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski 
[bhelgaas: changelog, rename functions]
Signed-off-by: Bjorn Helgaas

PCI/IOV: Allow PF drivers to limit total_VFs to 0

2018-05-25T13:18:34+00:00

Some SR-IOV PF drivers implement .sriov_configure(), which allows
user-space to enable VFs by writing the desired number of VFs to the sysfs
"sriov_numvfs" file (see sriov_numvfs_store()).

The PCI core limits the number of VFs to the TotalVFs advertised by the
device in its SR-IOV capability.  The PF driver can limit the number of VFs
to even fewer (it may have pre-allocated data structures or knowledge of
device limitations) by calling pci_sriov_set_totalvfs(), but previously it
could not limit the VFs to 0.

Change pci_sriov_get_totalvfs() so it always respects the VF limit imposed
by the PF driver, even if the limit is 0.

This sequence:

  pci_sriov_set_totalvfs(dev, 0);
  x = pci_sriov_get_totalvfs(dev);

previously set "x" to TotalVFs from the SR-IOV capability.  Now it will set
"x" to 0.

Signed-off-by: Jakub Kicinski 
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas

PCI/IOV: Add pci_sriov_configure_simple()

2018-04-24T21:46:56+00:00

SR-IOV (Single Root I/O Virtualization) is an optional PCIe capability (see
PCIe r4.0, sec 9).  A PCIe Function with the SR-IOV capability is referred
to as a PF (Physical Function).  If SR-IOV is enabled on the PF, several
VFs (Virtual Functions) may be created.  The VFs can be individually
assigned to virtual machines, which allows them to share a single hardware
device while being isolated from each other.

Some SR-IOV devices have resources such as queues and interrupts that must
be set up in the PF before enabling the VFs, so they require a PF driver to
do that.

Other SR-IOV devices don't require any PF setup before enabling VFs.  Add a
pci_sriov_configure_simple() interface so PF drivers for such devices can
use it without repeating the VF-enabling code.

Tested-by: Mark Rustad 
Signed-off-by: Alexander Duyck 
[bhelgaas: changelog, comment]
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Greg Rose 
Reviewed-by: Christoph Hellwig :wq

Merge branch 'pci/virtualization'

2018-04-04T18:28:26+00:00

  - probe for device reset support during enumeration instead of runtime
    (Bjorn Helgaas)

  - add ACS quirk for Ampere (née APM) root ports (Feng Kan)

  - add function 1 DMA alias quirk for Marvell 88SE9220 (Thomas
    Vincent-Cross)

  - protect device restore with device lock (Sinan Kaya)

  - handle failure of FLR gracefully (Sinan Kaya)

  - handle CRS (config retry status) after device resets (Sinan Kaya)

  - skip various config reads for SR-IOV VFs as an optimization (KarimAllah
    Ahmed)

* pci/virtualization:
  PCI/IOV: Add missing prototypes for powerpc pcibios interfaces
  PCI/IOV: Use VF0 cached config registers for other VFs
  PCI/IOV: Skip BAR sizing for VFs
  PCI/IOV: Skip INTx config reads for VFs
  PCI: Wait for device to become ready after secondary bus reset
  PCI: Add a return type for pci_reset_bridge_secondary_bus()
  PCI: Wait for device to become ready after a power management reset
  PCI: Rename pci_flr_wait() to pci_dev_wait() and make it generic
  PCI: Handle FLR failure and allow other reset types
  PCI: Protect restore with device lock to be consistent
  PCI: Add function 1 DMA alias quirk for Marvell 88SE9220
  PCI: Add ACS quirk for Ampere root ports
  PCI: Remove redundant probes for device reset support
  PCI: Probe for device reset support during enumeration

Conflicts:
	include/linux/pci.h