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+                         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