Documentation/rapidio/sysfs.txt - kernel/msm-4.9 - Gitiles

                          RapidIO sysfs Files

 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 1. RapidIO Device Subdirectories
 --------------------------------

 For each RapidIO device, the RapidIO subsystem creates files in an individual
 subdirectory with the following name, /sys/bus/rapidio/devices/<device_name>.

 The format of device_name is "nn:d:iiii", where:

 nn - two-digit hexadecimal ID of RapidIO network where the device resides
 d  - device typr: 'e' - for endpoint or 's' - for switch
 iiii - four-digit device destID for endpoints, or switchID for switches

 For example, below is a list of device directories that represents a typical
 RapidIO network with one switch, one host, and two agent endpoints, as it is
 seen by the enumerating host (destID = 1):

 /sys/bus/rapidio/devices/00:e:0000
 /sys/bus/rapidio/devices/00:e:0002
 /sys/bus/rapidio/devices/00:s:0001

 NOTE: An enumerating or discovering endpoint does not create a sysfs entry for
 itself, this is why an endpoint with destID=1 is not shown in the list.

 2. Attributes Common for All RapidIO Devices
 --------------------------------------------

 Each device subdirectory contains the following informational read-only files:

        did - returns the device identifier
        vid - returns the device vendor identifier
 device_rev - returns the device revision level
    asm_did - returns identifier for the assembly containing the device
    asm_rev - returns revision level of the assembly containing the device
    asm_vid - returns vendor identifier of the assembly containing the device
    destid  - returns device destination ID assigned by the enumeration routine
              (see 4.1 for switch specific details)
    lprev   - returns name of previous device (switch) on the path to the device
              that that owns this attribute
   modalias - returns the device modalias

 In addition to the files listed above, each device has a binary attribute file
 that allows read/write access to the device configuration registers using
 the RapidIO maintenance transactions:

  config - reads from and writes to the device configuration registers.

 This attribute is similar in behavior to the "config" attribute of PCI devices
 and provides an access to the RapidIO device registers using standard file read
 and write operations.

 3. RapidIO Endpoint Device Attributes
 -------------------------------------

 Currently Linux RapidIO subsystem does not create any endpoint specific sysfs
 attributes. It is possible that RapidIO master port drivers and endpoint device
 drivers will add their device-specific sysfs attributes but such attributes are
 outside the scope of this document.

 4. RapidIO Switch Device Attributes
 -----------------------------------

 RapidIO switches have additional attributes in sysfs. RapidIO subsystem supports
 common and device-specific sysfs attributes for switches. Because switches are
 integrated into the RapidIO subsystem, it offers a method to create
 device-specific sysfs attributes by specifying a callback function that may be
 set by the switch initialization routine during enumeration or discovery process.

 4.1 Common Switch Attributes

    routes - reports switch routing information in "destID port" format. This
             attribute reports only valid routing table entries, one line for
             each entry.
    destid - device destination ID that defines a route to the switch
  hopcount - number of hops on the path to the switch
     lnext - returns names of devices linked to the switch except one of a device
             linked to the ingress port (reported as "lprev"). This is an array
             names with number of lines equal to number of ports in switch. If
             a switch port has no attached device, returns "null" instead of
             a device name.

 4.2 Device-specific Switch Attributes

 Device-specific switch attributes are listed for each RapidIO switch driver
 that exports additional attributes.

 IDT_GEN2:
  errlog - reads contents of device error log until it is empty.


 5. RapidIO Bus Attributes
 -------------------------

 RapidIO bus subdirectory /sys/bus/rapidio implements the following bus-specific
 attribute:

   scan - allows to trigger enumeration discovery process from user space. This
 	 is a write-only attribute. To initiate an enumeration or discovery
 	 process on specific mport device, a user needs to write mport_ID (not
 	 RapidIO destination ID) into this file. The mport_ID is a sequential
 	 number (0 ... RIO_MAX_MPORTS) assigned to the mport device.
 	 For example, for a machine with a single RapidIO controller, mport_ID
 	 for that controller always will be 0.
 	 To initiate RapidIO enumeration/discovery on all available mports
 	 a user must write '-1' (or RIO_MPORT_ANY) into this attribute file.


 6. RapidIO Bus Controllers/Ports
 --------------------------------

 On-chip RapidIO controllers and PCIe-to-RapidIO bridges (referenced as
 "Master Port" or "mport") are presented in sysfs as the special class of
 devices: "rapidio_port".

 The /sys/class/rapidio_port subdirectory contains individual subdirectories
 named as "rapidioN" where N = mport ID registered with RapidIO subsystem.

 NOTE: An mport ID is not a RapidIO destination ID assigned to a given local
 mport device.

 Each mport device subdirectory in addition to standard entries contains the
 following device-specific attributes:

    port_destid - reports RapidIO destination ID assigned to the given RapidIO
                  mport device. If value 0xFFFFFFFF is returned this means that
                  no valid destination ID have been assigned to the mport (yet).
                  Normally, before enumeration/discovery have been executed only
                  fabric enumerating mports have a valid destination ID assigned
                  to them using "hdid=..." rapidio module parameter.
       sys_size - reports RapidIO common transport system size:
                    0 = small (8-bit destination ID, max. 256 devices),
                    1 = large (16-bit destination ID, max. 65536 devices).

 After enumeration or discovery was performed for a given mport device,
 the corresponding subdirectory will also contain subdirectories for each
 child RapidIO device connected to the mport. Naming conventions for RapidIO
 devices are described in Section 1 above.

 The example below shows mport device subdirectory with several child RapidIO
 devices attached to it.

 [rio@rapidio ~]$ ls /sys/class/rapidio_port/rapidio0/ -l
 total 0
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0001
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0004
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0007
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0002
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0003
 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0005
 lrwxrwxrwx 1 root root    0 Feb 11 15:11 device -> ../../../0000:01:00.0
 -r--r--r-- 1 root root 4096 Feb 11 15:11 port_destid
 drwxr-xr-x 2 root root    0 Feb 11 15:11 power
 lrwxrwxrwx 1 root root    0 Feb 11 15:04 subsystem -> ../../../../../../class/rapidio_port
 -r--r--r-- 1 root root 4096 Feb 11 15:11 sys_size
 -rw-r--r-- 1 root root 4096 Feb 11 15:04 uevent
	RapidIO sysfs Files

	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	1. RapidIO Device Subdirectories
	--------------------------------

	For each RapidIO device, the RapidIO subsystem creates files in an individual
	subdirectory with the following name, /sys/bus/rapidio/devices/<device_name>.

	The format of device_name is "nn:d:iiii", where:

	nn - two-digit hexadecimal ID of RapidIO network where the device resides
	d - device typr: 'e' - for endpoint or 's' - for switch
	iiii - four-digit device destID for endpoints, or switchID for switches

	For example, below is a list of device directories that represents a typical
	RapidIO network with one switch, one host, and two agent endpoints, as it is
	seen by the enumerating host (destID = 1):

	/sys/bus/rapidio/devices/00:e:0000
	/sys/bus/rapidio/devices/00:e:0002
	/sys/bus/rapidio/devices/00:s:0001

	NOTE: An enumerating or discovering endpoint does not create a sysfs entry for
	itself, this is why an endpoint with destID=1 is not shown in the list.

	2. Attributes Common for All RapidIO Devices
	--------------------------------------------

	Each device subdirectory contains the following informational read-only files:

	did - returns the device identifier
	vid - returns the device vendor identifier
	device_rev - returns the device revision level
	asm_did - returns identifier for the assembly containing the device
	asm_rev - returns revision level of the assembly containing the device
	asm_vid - returns vendor identifier of the assembly containing the device
	destid - returns device destination ID assigned by the enumeration routine
	(see 4.1 for switch specific details)
	lprev - returns name of previous device (switch) on the path to the device
	that that owns this attribute
	modalias - returns the device modalias

	In addition to the files listed above, each device has a binary attribute file
	that allows read/write access to the device configuration registers using
	the RapidIO maintenance transactions:

	config - reads from and writes to the device configuration registers.

	This attribute is similar in behavior to the "config" attribute of PCI devices
	and provides an access to the RapidIO device registers using standard file read
	and write operations.

	3. RapidIO Endpoint Device Attributes
	-------------------------------------

	Currently Linux RapidIO subsystem does not create any endpoint specific sysfs
	attributes. It is possible that RapidIO master port drivers and endpoint device
	drivers will add their device-specific sysfs attributes but such attributes are
	outside the scope of this document.

	4. RapidIO Switch Device Attributes
	-----------------------------------

	RapidIO switches have additional attributes in sysfs. RapidIO subsystem supports
	common and device-specific sysfs attributes for switches. Because switches are
	integrated into the RapidIO subsystem, it offers a method to create
	device-specific sysfs attributes by specifying a callback function that may be
	set by the switch initialization routine during enumeration or discovery process.

	4.1 Common Switch Attributes

	routes - reports switch routing information in "destID port" format. This
	attribute reports only valid routing table entries, one line for
	each entry.
	destid - device destination ID that defines a route to the switch
	hopcount - number of hops on the path to the switch
	lnext - returns names of devices linked to the switch except one of a device
	linked to the ingress port (reported as "lprev"). This is an array
	names with number of lines equal to number of ports in switch. If
	a switch port has no attached device, returns "null" instead of
	a device name.

	4.2 Device-specific Switch Attributes

	Device-specific switch attributes are listed for each RapidIO switch driver
	that exports additional attributes.

	IDT_GEN2:
	errlog - reads contents of device error log until it is empty.


	5. RapidIO Bus Attributes
	-------------------------

	RapidIO bus subdirectory /sys/bus/rapidio implements the following bus-specific
	attribute:

	scan - allows to trigger enumeration discovery process from user space. This
	is a write-only attribute. To initiate an enumeration or discovery
	process on specific mport device, a user needs to write mport_ID (not
	RapidIO destination ID) into this file. The mport_ID is a sequential
	number (0 ... RIO_MAX_MPORTS) assigned to the mport device.
	For example, for a machine with a single RapidIO controller, mport_ID
	for that controller always will be 0.
	To initiate RapidIO enumeration/discovery on all available mports
	a user must write '-1' (or RIO_MPORT_ANY) into this attribute file.


	6. RapidIO Bus Controllers/Ports
	--------------------------------

	On-chip RapidIO controllers and PCIe-to-RapidIO bridges (referenced as
	"Master Port" or "mport") are presented in sysfs as the special class of
	devices: "rapidio_port".

	The /sys/class/rapidio_port subdirectory contains individual subdirectories
	named as "rapidioN" where N = mport ID registered with RapidIO subsystem.

	NOTE: An mport ID is not a RapidIO destination ID assigned to a given local
	mport device.

	Each mport device subdirectory in addition to standard entries contains the
	following device-specific attributes:

	port_destid - reports RapidIO destination ID assigned to the given RapidIO
	mport device. If value 0xFFFFFFFF is returned this means that
	no valid destination ID have been assigned to the mport (yet).
	Normally, before enumeration/discovery have been executed only
	fabric enumerating mports have a valid destination ID assigned
	to them using "hdid=..." rapidio module parameter.
	sys_size - reports RapidIO common transport system size:
	0 = small (8-bit destination ID, max. 256 devices),
	1 = large (16-bit destination ID, max. 65536 devices).

	After enumeration or discovery was performed for a given mport device,
	the corresponding subdirectory will also contain subdirectories for each
	child RapidIO device connected to the mport. Naming conventions for RapidIO
	devices are described in Section 1 above.

	The example below shows mport device subdirectory with several child RapidIO
	devices attached to it.

	[rio@rapidio ~]$ ls /sys/class/rapidio_port/rapidio0/ -l
	total 0
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0001
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0004
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0007
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0002
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0003
	drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0005
	lrwxrwxrwx 1 root root 0 Feb 11 15:11 device -> ../../../0000:01:00.0
	-r--r--r-- 1 root root 4096 Feb 11 15:11 port_destid
	drwxr-xr-x 2 root root 0 Feb 11 15:11 power
	lrwxrwxrwx 1 root root 0 Feb 11 15:04 subsystem -> ../../../../../../class/rapidio_port
	-r--r--r-- 1 root root 4096 Feb 11 15:11 sys_size
	-rw-r--r-- 1 root root 4096 Feb 11 15:04 uevent