diff options
| author | Stephen Hemminger <sthemmin@microsoft.com> | 2016-10-17 12:33:19 -0700 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2016-10-21 15:10:06 -0600 |
| commit | a164a8a6635469b653fa132a3ec283df6bc147f4 (patch) | |
| tree | f8fd92bfe57d04664eedb67f9ff6bf66b8867076 | |
| parent | 5ac9baf47a571d74c995529b2f7ded8348389e10 (diff) | |
doc: add documentation for uio-hv-generic
Update UIO documentation to include basic information about
uio_hv_generic.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| -rw-r--r-- | Documentation/DocBook/uio-howto.tmpl | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl index cd0e452dfed5..5210f8a577c6 100644 --- a/Documentation/DocBook/uio-howto.tmpl +++ b/Documentation/DocBook/uio-howto.tmpl @@ -46,6 +46,13 @@ GPL version 2. <revhistory> <revision> + <revnumber>0.10</revnumber> + <date>2016-10-17</date> + <authorinitials>sch</authorinitials> + <revremark>Added generic hyperv driver + </revremark> + </revision> + <revision> <revnumber>0.9</revnumber> <date>2009-07-16</date> <authorinitials>mst</authorinitials> @@ -1033,6 +1040,61 @@ int main() </chapter> +<chapter id="uio_hv_generic" xreflabel="Using Generic driver for Hyper-V VMBUS"> +<?dbhtml filename="uio_hv_generic.html"?> +<title>Generic Hyper-V UIO driver</title> + <para> + The generic driver is a kernel module named uio_hv_generic. + It supports devices on the Hyper-V VMBus similar to uio_pci_generic + on PCI bus. + </para> + +<sect1 id="uio_hv_generic_binding"> +<title>Making the driver recognize the device</title> + <para> +Since the driver does not declare any device GUID's, it will not get loaded +automatically and will not automatically bind to any devices, you must load it +and allocate id to the driver yourself. For example, to use the network device +GUID: + <programlisting> + modprobe uio_hv_generic + echo "f8615163-df3e-46c5-913f-f2d2f965ed0e" > /sys/bus/vmbus/drivers/uio_hv_generic/new_id + </programlisting> + </para> + <para> +If there already is a hardware specific kernel driver for the device, the +generic driver still won't bind to it, in this case if you want to use the +generic driver (why would you?) you'll have to manually unbind the hardware +specific driver and bind the generic driver, like this: + <programlisting> + echo -n vmbus-ed963694-e847-4b2a-85af-bc9cfc11d6f3 > /sys/bus/vmbus/drivers/hv_netvsc/unbind + echo -n vmbus-ed963694-e847-4b2a-85af-bc9cfc11d6f3 > /sys/bus/vmbus/drivers/uio_hv_generic/bind + </programlisting> + </para> + <para> +You can verify that the device has been bound to the driver +by looking for it in sysfs, for example like the following: + <programlisting> + ls -l /sys/bus/vmbus/devices/vmbus-ed963694-e847-4b2a-85af-bc9cfc11d6f3/driver + </programlisting> +Which if successful should print + <programlisting> + .../vmbus-ed963694-e847-4b2a-85af-bc9cfc11d6f3/driver -> ../../../bus/vmbus/drivers/uio_hv_generic + </programlisting> + </para> +</sect1> + +<sect1 id="uio_hv_generic_internals"> +<title>Things to know about uio_hv_generic</title> + <para> +On each interrupt, uio_hv_generic sets the Interrupt Disable bit. +This prevents the device from generating further interrupts +until the bit is cleared. The userspace driver should clear this +bit before blocking and waiting for more interrupts. + </para> +</sect1> +</chapter> + <appendix id="app1"> <title>Further information</title> <itemizedlist> |