Documentation/rapidio/sysfs.txt

   1                          RapidIO sysfs Files
   2
   3 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4
   5 1. 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 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. 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. 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.