summaryrefslogtreecommitdiffstats
path: root/Documentation/ABI/testing
diff options
context:
space:
mode:
authorDonald Dutile <ddutile@redhat.com>2012-11-27 22:31:37 -0500
committerBjorn Helgaas <bhelgaas@google.com>2012-11-28 11:25:47 -0700
commit2597ba763fc44e247e462177abfe92d95bc5e6d5 (patch)
tree7d971907328ceb025fc079fba4ce2b73c442b70d /Documentation/ABI/testing
parent1452cd76a97bf7b93a015586dcabc73fd935e692 (diff)
PCI: SRIOV control and status via sysfs (documentation)
Add documentation of new sysfs files and new pci_driver SRIOV configuration interface. [bhelgaas: changelog] Signed-off: Donald Dutile <ddutile@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'Documentation/ABI/testing')
-rw-r--r--Documentation/ABI/testing/sysfs-bus-pci34
1 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index dff1f48d252..1ce5ae329c0 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -222,3 +222,37 @@ Description:
satisfied too. Reading this attribute will show the current
value of d3cold_allowed bit. Writing this attribute will set
the value of d3cold_allowed bit.
+
+What: /sys/bus/pci/devices/.../sriov_totalvfs
+Date: November 2012
+Contact: Donald Dutile <ddutile@redhat.com>
+Description:
+ This file appears when a physical PCIe device supports SR-IOV.
+ Userspace applications can read this file to determine the
+ maximum number of Virtual Functions (VFs) a PCIe physical
+ function (PF) can support. Typically, this is the value reported
+ in the PF's SR-IOV extended capability structure's TotalVFs
+ element. Drivers have the ability at probe time to reduce the
+ value read from this file via the pci_sriov_set_totalvfs()
+ function.
+
+What: /sys/bus/pci/devices/.../sriov_numvfs
+Date: November 2012
+Contact: Donald Dutile <ddutile@redhat.com>
+Description:
+ This file appears when a physical PCIe device supports SR-IOV.
+ Userspace applications can read and write to this file to
+ determine and control the enablement or disablement of Virtual
+ Functions (VFs) on the physical function (PF). A read of this
+ file will return the number of VFs that are enabled on this PF.
+ A number written to this file will enable the specified
+ number of VFs. A userspace application would typically read the
+ file and check that the value is zero, and then write the number
+ of VFs that should be enabled on the PF; the value written
+ should be less than or equal to the value in the sriov_totalvfs
+ file. A userspace application wanting to disable the VFs would
+ write a zero to this file. The core ensures that valid values
+ are written to this file, and returns errors when values are not
+ valid. For example, writing a 2 to this file when sriov_numvfs
+ is not 0 and not 2 already will return an error. Writing a 10
+ when the value of sriov_totalvfs is 8 will return an error.