Documentation/scsi/hpsa.txt

   1
   2 HPSA - Hewlett Packard Smart Array driver
   3 -----------------------------------------
   4
   5 This file describes the hpsa SCSI driver for HP Smart Array controllers.
   6 The hpsa driver is intended to supplant the cciss driver for newer
   7 Smart Array controllers.  The hpsa driver is a SCSI driver, while the
   8 cciss driver is a "block" driver.  Actually cciss is both a block
   9 driver (for logical drives) AND a SCSI driver (for tape drives). This
  10 "split-brained" design of the cciss driver is a source of excess
  11 complexity and eliminating that complexity is one of the reasons
  12 for hpsa to exist.
  13
  14 Supported devices:
  15 ------------------
  16
  17 Smart Array P212
  18 Smart Array P410
  19 Smart Array P410i
  20 Smart Array P411
  21 Smart Array P812
  22 Smart Array P712m
  23 Smart Array P711m
  24 StorageWorks P1210m
  25
  26 Additionally, older Smart Arrays may work with the hpsa driver if the kernel
  27 boot parameter "hpsa_allow_any=1" is specified, however these are not tested
  28 nor supported by HP with this driver.  For older Smart Arrays, the cciss
  29 driver should still be used.
  30
  31 The "hpsa_simple_mode=1" boot parameter may be used to prevent the driver from
  32 putting the controller into "performant" mode.  The difference is that with simple
  33 mode, each command completion requires an interrupt, while with "performant mode"
  34 (the default, and ordinarily better performing) it is possible to have multiple
  35 command completions indicated by a single interrupt.
  36
  37 HPSA specific entries in /sys
  38 -----------------------------
  39
  40   In addition to the generic SCSI attributes available in /sys, hpsa supports
  41   the following attributes:
  42
  43   HPSA specific host attributes:
  44   ------------------------------
  45
  46   /sys/class/scsi_host/host*/rescan
  47   /sys/class/scsi_host/host*/firmware_revision
  48
  49   the host "rescan" attribute is a write only attribute.  Writing to this
  50   attribute will cause the driver to scan for new, changed, or removed devices
  51   (e.g. hot-plugged tape drives, or newly configured or deleted logical drives,
  52   etc.) and notify the SCSI midlayer of any changes detected.  Normally this is
  53   triggered automatically by HP's Array Configuration Utility (either the GUI or
  54   command line variety) so for logical drive changes, the user should not
  55   normally have to use this.  It may be useful when hot plugging devices like
  56   tape drives, or entire storage boxes containing pre-configured logical drives.
  57
  58   The "firmware_revision" attribute contains the firmware version of the Smart Array.
  59   For example:
  60
  61         root@host:/sys/class/scsi_host/host4# cat firmware_revision
  62         7.14
  63
  64   HPSA specific disk attributes:
  65   ------------------------------
  66
  67   /sys/class/scsi_disk/c:b:t:l/device/unique_id
  68   /sys/class/scsi_disk/c:b:t:l/device/raid_level
  69   /sys/class/scsi_disk/c:b:t:l/device/lunid
  70
  71   (where c:b:t:l are the controller, bus, target and lun of the device)
  72
  73   For example:
  74
  75         root@host:/sys/class/scsi_disk/4:0:0:0/device# cat unique_id
  76         600508B1001044395355323037570F77
  77         root@host:/sys/class/scsi_disk/4:0:0:0/device# cat lunid
  78         0x0000004000000000
  79         root@host:/sys/class/scsi_disk/4:0:0:0/device# cat raid_level
  80         RAID 0
  81
  82 HPSA specific ioctls:
  83 ---------------------
  84
  85   For compatibility with applications written for the cciss driver, many, but
  86   not all of the ioctls supported by the cciss driver are also supported by the
  87   hpsa driver.  The data structures used by these are described in
  88   include/linux/cciss_ioctl.h
  89
  90   CCISS_DEREGDISK
  91   CCISS_REGNEWDISK
  92   CCISS_REGNEWD
  93
  94   The above three ioctls all do exactly the same thing, which is to cause the driver
  95   to rescan for new devices.  This does exactly the same thing as writing to the
  96   hpsa specific host "rescan" attribute.
  97
  98   CCISS_GETPCIINFO
  99
 100         Returns PCI domain, bus, device and function and "board ID" (PCI subsystem ID).
 101
 102   CCISS_GETDRIVVER
 103
 104         Returns driver version in three bytes encoded as:
 105                 (major_version << 16) | (minor_version << 8) | (subminor_version)
 106
 107   CCISS_PASSTHRU
 108   CCISS_BIG_PASSTHRU
 109
 110         Allows "BMIC" and "CISS" commands to be passed through to the Smart Array.
 111         These are used extensively by the HP Array Configuration Utility, SNMP storage
 112         agents, etc.  See cciss_vol_status at http://cciss.sf.net for some examples.
 113