diff options
Diffstat (limited to 'Documentation/PCI/endpoint/pci-endpoint-cfs.rst')
| -rw-r--r-- | Documentation/PCI/endpoint/pci-endpoint-cfs.rst | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/Documentation/PCI/endpoint/pci-endpoint-cfs.rst b/Documentation/PCI/endpoint/pci-endpoint-cfs.rst index b6d39cdec56e..fb73345cfb8a 100644 --- a/Documentation/PCI/endpoint/pci-endpoint-cfs.rst +++ b/Documentation/PCI/endpoint/pci-endpoint-cfs.rst @@ -24,7 +24,7 @@ Directory Structure The pci_ep configfs has two directories at its root: controllers and functions. Every EPC device present in the system will have an entry in -the *controllers* directory and and every EPF driver present in the system +the *controllers* directory and every EPF driver present in the system will have an entry in the *functions* directory. :: @@ -43,6 +43,7 @@ entries corresponding to EPF driver will be created by the EPF core. .. <EPF Driver1>/ ... <EPF Device 11>/ ... <EPF Device 21>/ + ... <EPF Device 31>/ .. <EPF Driver2>/ ... <EPF Device 12>/ ... <EPF Device 22>/ @@ -68,6 +69,24 @@ created) ... subsys_vendor_id ... subsys_id ... interrupt_pin + ... <Symlink EPF Device 31>/ + ... primary/ + ... <Symlink EPC Device1>/ + ... secondary/ + ... <Symlink EPC Device2>/ + +If an EPF device has to be associated with 2 EPCs (like in the case of +Non-transparent bridge), symlink of endpoint controller connected to primary +interface should be added in 'primary' directory and symlink of endpoint +controller connected to secondary interface should be added in 'secondary' +directory. + +The <EPF Device> directory can have a list of symbolic links +(<Symlink EPF Device 31>) to other <EPF Device>. These symbolic links should +be created by the user to represent the virtual functions that are bound to +the physical function. In the above directory structure <EPF Device 11> is a +physical function and <EPF Device 31> is a virtual function. An EPF device once +it's linked to another EPF device, cannot be linked to a EPC device. EPC Device ========== @@ -88,7 +107,8 @@ entries corresponding to EPC device will be created by the EPC core. The <EPC Device> directory will have a list of symbolic links to <EPF Device>. These symbolic links should be created by the user to -represent the functions present in the endpoint device. +represent the functions present in the endpoint device. Only <EPF Device> +that represents a physical function can be linked to a EPC device. The <EPC Device> directory will also have a *start* field. Once "1" is written to this field, the endpoint device will be ready to @@ -115,4 +135,4 @@ all the EPF devices are created and linked with the EPC device. | interrupt_pin | function -[1] :doc:`pci-endpoint` +[1] Documentation/PCI/endpoint/pci-endpoint.rst |