SAS: This is a SAM implementation of Serial Attached SCSI (SAS) disk controller.
It models LSI SAS1064E, which is designed based on the Fusion-MPT (Message Passing 
Technology) architecture. It has PCIE interface through which the controller can 
be connected to any PCIE bus. Each controller can support up to 4 SAS disks (target 0~3). 
This implementation does not include a timing model, so the I/O request is served and 
completed immediately after it is received by the controller assuming no simulated 
disk delay. Also, the SAS disk is implemented based on a generic disk model.


a) sysconf format for this module
sysconf sas <instance name> bus=<bus name> dev=<device id> fun=<function number>
targets=<init file> [-d[0|1|2]]
where,
'instance name' is the name of this controller;
'bus name' is the name of PCIE bus this controller is to be connected;
'device number' is the PCIE device number;
'function number' is the PCIE function number;
'init file' is the configuration file for the attached SAS disks;
'-d' is the optional argument that sets the debug level to 0, 1 or 2.

Examples sysconf line:
sysconf sas sas0 bus=pcie_a dev=0 fun=1 targets=sasdisk.init -d2
# A SAS controller called "sas0" is attached to PCIE bus "pcie_a" as device 0 function 1.
# The configuration for the attached disks is in file "sasdisk.init".
# The debug level is set to 2.


b) UI commands for this module
ui format: <instance name> <command> <command args>
  commands are:
    debug [<level>]
      - set the debug level for debug prints to 'level'
        if 'level' not provided, print current debug level
        'level' = [0|1|2]
    disk
      - show all attached disks
All the above information is available by typing <instance name> on SAM UI prompt.
Eg, 'sas0' based on above example sysconf line.


c) UI commands for attached disks
ui format: gdisk <disk name> <command> <command args>
  commands are:
    label
      - display disk label
    geometry
      - display disk geometry
    stat
      - display any supported stats
    partitions [number]
      - display partition[number] info
      - display all partitions by default
    vpd
      - display supported disk VPD data
    op [file]
      - redirect all o/p to <file>
      - by default print current op file
    debug [level]
      - set debug verbosity to <level>
All the above information is available by typing 'gdisk help' on SAM UI prompt.
Also, typing 'gdisk' will list all attached disks in the system.