diff options
| author | Yijing Wang <wangyijing@huawei.com> | 2014-09-23 13:27:24 +0800 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2014-10-01 12:21:23 -0600 |
| commit | 468ff15a3ab98ed7153c29c68229ffb97f15a251 (patch) | |
| tree | 33726cffacff157deb298a562ebac0d1062725d6 /Documentation/ABI/testing | |
| parent | 48c3c38f003c25d50a09d3da558667c5ecd530aa (diff) | |
PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpoints
The "msi_bus" sysfs file for bridges sets a bus flag to allow or disallow
future driver requests for MSI or MSI-X. Previously, the sysfs file
existed for endpoints but did nothing.
Add "msi_bus" support for endpoints, so an administrator can prevent the
use of MSI and MSI-X for individual devices.
Note that as for bridges, these changes only affect future driver requests
for MSI or MSI-X, so drivers may need to be reloaded.
Add documentation for the "msi_bus" sysfs file.
[bhelgaas: changelog, comments, add "subordinate", add endpoint printk,
rework bus_flags setting, make bus_flags printk unconditional]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'Documentation/ABI/testing')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 6615fda0abfb..ee6c04036492 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -65,6 +65,16 @@ Description: force a rescan of all PCI buses in the system, and re-discover previously removed devices. +What: /sys/bus/pci/devices/.../msi_bus +Date: September 2014 +Contact: Linux PCI developers <linux-pci@vger.kernel.org> +Description: + Writing a zero value to this attribute disallows MSI and + MSI-X for any future drivers of the device. If the device + is a bridge, MSI and MSI-X will be disallowed for future + drivers of all child devices under the bridge. Drivers + must be reloaded for the new setting to take effect. + What: /sys/bus/pci/devices/.../msi_irqs/ Date: September, 2011 Contact: Neil Horman <nhorman@tuxdriver.com> |