Documentation/rapidio/sysfs.txt

   1                          RapidIO sysfs Files
   2
   3 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4
   5 1. RapidIO Device Subdirectories
   6 --------------------------------
   7
   8 For each RapidIO device, the RapidIO subsystem creates files in an individual
   9 subdirectory with the following name, /sys/bus/rapidio/devices/<device_name>.
  10
  11 The format of device_name is "nn:d:iiii", where:
  12
  13 nn - two-digit hexadecimal ID of RapidIO network where the device resides
  14 d  - device typr: 'e' - for endpoint or 's' - for switch
  15 iiii - four-digit device destID for endpoints, or switchID for switches
  16
  17 For example, below is a list of device directories that represents a typical
  18 RapidIO network with one switch, one host, and two agent endpoints, as it is
  19 seen by the enumerating host (destID = 1):
  20
  21 /sys/bus/rapidio/devices/00:e:0000
  22 /sys/bus/rapidio/devices/00:e:0002
  23 /sys/bus/rapidio/devices/00:s:0001
  24
  25 NOTE: An enumerating or discovering endpoint does not create a sysfs entry for
  26 itself, this is why an endpoint with destID=1 is not shown in the list.
  27
  28 2. Attributes Common for All RapidIO Devices
  29 --------------------------------------------
  30
  31 Each device subdirectory contains the following informational read-only files:
  32
  33        did - returns the device identifier
  34        vid - returns the device vendor identifier
  35 device_rev - returns the device revision level
  36    asm_did - returns identifier for the assembly containing the device
  37    asm_rev - returns revision level of the assembly containing the device
  38    asm_vid - returns vendor identifier of the assembly containing the device
  39    destid  - returns device destination ID assigned by the enumeration routine
  40              (see 4.1 for switch specific details)
  41    lprev   - returns name of previous device (switch) on the path to the device
  42              that that owns this attribute
  43   modalias - returns the device modalias
  44
  45 In addition to the files listed above, each device has a binary attribute file
  46 that allows read/write access to the device configuration registers using
  47 the RapidIO maintenance transactions:
  48
  49  config - reads from and writes to the device configuration registers.
  50
  51 This attribute is similar in behavior to the "config" attribute of PCI devices
  52 and provides an access to the RapidIO device registers using standard file read
  53 and write operations.
  54
  55 3. RapidIO Endpoint Device Attributes
  56 -------------------------------------
  57
  58 Currently Linux RapidIO subsystem does not create any endpoint specific sysfs
  59 attributes. It is possible that RapidIO master port drivers and endpoint device
  60 drivers will add their device-specific sysfs attributes but such attributes are
  61 outside the scope of this document.
  62
  63 4. RapidIO Switch Device Attributes
  64 -----------------------------------
  65
  66 RapidIO switches have additional attributes in sysfs. RapidIO subsystem supports
  67 common and device-specific sysfs attributes for switches. Because switches are
  68 integrated into the RapidIO subsystem, it offers a method to create
  69 device-specific sysfs attributes by specifying a callback function that may be
  70 set by the switch initialization routine during enumeration or discovery process.
  71
  72 4.1 Common Switch Attributes
  73
  74    routes - reports switch routing information in "destID port" format. This
  75             attribute reports only valid routing table entries, one line for
  76             each entry.
  77    destid - device destination ID that defines a route to the switch
  78  hopcount - number of hops on the path to the switch
  79     lnext - returns names of devices linked to the switch except one of a device
  80             linked to the ingress port (reported as "lprev"). This is an array
  81             names with number of lines equal to number of ports in switch. If
  82             a switch port has no attached device, returns "null" instead of
  83             a device name.
  84
  85 4.2 Device-specific Switch Attributes
  86
  87 Device-specific switch attributes are listed for each RapidIO switch driver
  88 that exports additional attributes.
  89
  90 IDT_GEN2:
  91  errlog - reads contents of device error log until it is empty.
  92
  93
  94 5. RapidIO Bus Attributes
  95 -------------------------
  96
  97 RapidIO bus subdirectory /sys/bus/rapidio implements the following bus-specific
  98 attribute:
  99
 100   scan - allows to trigger enumeration discovery process from user space. This
 101          is a write-only attribute. To initiate an enumeration or discovery
 102          process on specific mport device, a user needs to write mport_ID (not
 103          RapidIO destination ID) into this file. The mport_ID is a sequential
 104          number (0 ... RIO_MAX_MPORTS) assigned to the mport device.
 105          For example, for a machine with a single RapidIO controller, mport_ID
 106          for that controller always will be 0.
 107          To initiate RapidIO enumeration/discovery on all available mports
 108          a user must write '-1' (or RIO_MPORT_ANY) into this attribute file.
 109
 110
 111 6. RapidIO Bus Controllers/Ports
 112 --------------------------------
 113
 114 On-chip RapidIO controllers and PCIe-to-RapidIO bridges (referenced as
 115 "Master Port" or "mport") are presented in sysfs as the special class of
 116 devices: "rapidio_port".
 117
 118 The /sys/class/rapidio_port subdirectory contains individual subdirectories
 119 named as "rapidioN" where N = mport ID registered with RapidIO subsystem.
 120
 121 NOTE: An mport ID is not a RapidIO destination ID assigned to a given local
 122 mport device.
 123
 124 Each mport device subdirectory in addition to standard entries contains the
 125 following device-specific attributes:
 126
 127    port_destid - reports RapidIO destination ID assigned to the given RapidIO
 128                  mport device. If value 0xFFFFFFFF is returned this means that
 129                  no valid destination ID have been assigned to the mport (yet).
 130                  Normally, before enumeration/discovery have been executed only
 131                  fabric enumerating mports have a valid destination ID assigned
 132                  to them using "hdid=..." rapidio module parameter.
 133       sys_size - reports RapidIO common transport system size:
 134                    0 = small (8-bit destination ID, max. 256 devices),
 135                    1 = large (16-bit destination ID, max. 65536 devices).
 136
 137 After enumeration or discovery was performed for a given mport device,
 138 the corresponding subdirectory will also contain subdirectories for each
 139 child RapidIO device connected to the mport. Naming conventions for RapidIO
 140 devices are described in Section 1 above.
 141
 142 The example below shows mport device subdirectory with several child RapidIO
 143 devices attached to it.
 144
 145 [rio@rapidio ~]$ ls /sys/class/rapidio_port/rapidio0/ -l
 146 total 0
 147 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0001
 148 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0004
 149 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:e:0007
 150 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0002
 151 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0003
 152 drwxr-xr-x 3 root root    0 Feb 11 15:10 00:s:0005
 153 lrwxrwxrwx 1 root root    0 Feb 11 15:11 device -> ../../../0000:01:00.0
 154 -r--r--r-- 1 root root 4096 Feb 11 15:11 port_destid
 155 drwxr-xr-x 2 root root    0 Feb 11 15:11 power
 156 lrwxrwxrwx 1 root root    0 Feb 11 15:04 subsystem -> ../../../../../../class/rapidio_port
 157 -r--r--r-- 1 root root 4096 Feb 11 15:11 sys_size
 158 -rw-r--r-- 1 root root 4096 Feb 11 15:04 uevent