man > sg_ses_microcode(8)

SG_SES_MICROCODE(8)                           SG3_UTILS                          SG_SES_MICROCODE(8)

NAME
       sg_ses_microcode - send microcode to a SCSI enclosure

SYNOPSIS
       sg_ses_microcode    [--bpw=CS]   [--dry-run]   [--ealsd]   [--help]   [--id=ID]   [--in=FILE]
       [--length=LEN]    [--mode=MO]    [--non]    [--offset=OFF]    [--skip=SKIP]     [--subenc=MS]
       [--tlength=TLEN] [--verbose] [--version] DEVICE

DESCRIPTION
       This  utility  attempts  to download microcode to an enclosure (or one of its sub-enclosures)
       associated with the DEVICE. The process for doing this is defined in the SCSI Enclosure  Ser‐
       vices (SES) standards and drafts maintained by the T10 committee.

       The  process  is to send one or more sequences containing a SCSI SEND DIAGNOSTIC command fol‐
       lowed optionally by a RECEIVE DIAGNOSTIC RESULTS command. The former sends a Download microc‐
       ode Control diagnostic page (dpage) and the latter fetches a Download microcode status  dpage
       which can be viewed as a report on the former command.

       The default action (i.e. when the --mode=MO option is not given) is to fetch the Download mi‐
       crocode  status dpage and decode it. This does not require the microcode (firmware) itself so
       the --in=FILE option is not required.

       The most recent reference for this utility is the draft SCSI  Enclosure  Services  3  (SES-3)
       document  T10/2149-D Revision 7 at http://www.t10.org .  Existing standards for SES and SES-2
       are ANSI INCITS 305-1998 and ANSI INCITS 448-2008 respectively.

       Most other support for SES in this package (apart from downloading microcode) can be found in
       the sg_ses utility. Another way of downloading firmware to a SCSI device is  with  the  WRITE
       BUFFER command defined in SPC-4, see the sg_write_buffer utility.

OPTIONS
       Arguments to long options are mandatory for short options as well.

       -b, --bpw=CS
              where  CS  is the chunk size in bytes and should be a multiple of 4.  This will be the
              maximum number of bytes sent per SEND DIAGNOSTIC command.  So if CS is less  than  the
              effective  length  of  the  microcode then multiple SEND DIAGNOSTIC commands are sent,
              each taking the next chunk from the read data and increasing the buffer  offset  field
              in  the  Download  microcode control dpage by the appropriate amount. The default is a
              chunk size of 0 which is interpreted as a very large number hence only one SEND  DIAG‐
              NOSTIC command will be sent.
              The  number  in  CS can optionally be followed by ",act" or ",activate".  In this case
              after the microcode has been successfully sent to the DEVICE, an  additional  Download
              microcode  control  dpage  with its mode set to "Activate deferred microcode" [0xf] is
              sent.

       -d, --dry-run
              the actual calls to perform SEND DIAGNOSTIC and RECEIVE  DIAGNOSTIC  RESULTS  commands
              are  skipped when this option is given. No SCSI commands are sent to the DEVICE but it
              is still opened and is required to be given.  A dummy device  such  as  /dev/null  (in
              Unix) can be used.
              This  utility  expects a "sensible" response to the RECEIVE DIAGNOSTIC RESULTS command
              it sends (and will abort if it doesn't receive one). So this option supplies dummy re‐
              sponses with one primary enclosure and three sub-enclosures. The dummy  responses  in‐
              clude good status values.

       -e, --ealsd
              exit  after  last  SEND DIAGNOSTIC command. A SES device should not start its firmware
              update immediately after the last received "chunk" of its firmware.  Rather it  should
              wait till at least one RECEIVE DIAGNOSTIC RESULTS command is sent to give the device a
              chance  to report any error. However some devices do start the firmware update immedi‐
              ately which causes the trailing RECEIVE DIAGNOSTIC RESULTS command to be held  up  and
              often be aborted with a "target reset" error.
              This option causes the trailing RECEIVE DIAGNOSTIC RESULTS command to be skipped. This
              option would be typically used with the --bpw=CS option.
              Prior  to version 1.10 of this utility [20180112] this (i.e. skipping the last RECEIVE
              DIAGNOSTIC RESULTS command) was the default action.

       -h, --help
              output the usage message then exit. If used multiple times also prints the mode  names
              and their acronyms.

       -i, --id=ID
              this  option sets the BUFFER ID field in the Download microcode control dpage. ID is a
              value between 0 (default) and 255 inclusive.

       -I, --in=FILE
              read data from file FILE that will be sent with the SEND DIAGNOSTIC command.  If  FILE
              is '-' then stdin is read until an EOF is detected (this is the same action as --raw).
              Data  is  read from the beginning of FILE except in the case when it is a regular file
              and the --skip=SKIP option is given.

       -l, --length=LEN
              where LEN is the length, in bytes, of data to be written to the device.  If not  given
              (and  the  length cannot be deduced from --in=FILE or --raw) then defaults to zero. If
              the option is given and the length deduced from --in=FILE or --raw is less (or no data
              is provided), then bytes of 0xff are used as fill bytes.

       -m, --mode=MO
              this option sets the MODE. MO is a value between 0 (which is dmc_status  and  the  de‐
              fault)  and  255  inclusive. Alternatively an abbreviation can be given. See the MODES
              section below. To list the available mode abbreviations at run time  give  an  invalid
              one (e.g. '--mode=xxx') or use the '-h' option.

       -N, --non
              allow  for non-standard implementations that reset their Download microcode engine af‐
              ter a RECEIVE DIAGNOSTIC RESULTS command with the Download microcode status  dpage  is
              sent.  When this option is given sending that command and dpage combination is avoided
              unless an error has already occurred.

       -o, --offset=OFF
              this option sets the BUFFER OFFSET field in the Download microcode control dpage.  OFF
              is  a  value between 0 (default) and 2**32-1 . It is a byte offset. This option is ig‐
              nored (and a warning sent to stderr) if the --bpw=CS option is also given.

       -s, --skip=SKIP
              this option is only active when --in=FILE is given and FILE is a regular file,  rather
              than  stdin.  Data  is  read  starting  at byte offset SKIP to the end of file (or the
              amount given by --length=LEN).  If not given the byte offset defaults to 0  (i.e.  the
              start of the file).

       -S, --subenc=SEID
              SEID  is  the  sub-enclosure identify. It defaults to 0 which is the primary enclosure
              identifier.

       -t, --tlength=TLEN
              TLEN is the total length in bytes of the microcode to be (or being) downloaded. It de‐
              faults to 0 which is okay in most cases. This option only comes into play when TLEN is
              greater than LEN. In this case TLEN is sent to the SES DEVICE so that it knows when it
              only receives LEN bytes from this invocation, that it should expect more to be sent in
              the near future (e.g. by another invocation). This option is only needed when sections
              of microcode are being sent in separate invocations of this utility (e.g. the  microc‐
              ode is spread across two files).

       -v, --verbose
              increase the level of verbosity, (i.e. debug output).

       -V, --version
              print the version string and then exit.

MODES
       Following  is  a list accepted by the MO argument of this utility.  First shown is an acronym
       followed in square brackets by the corresponding decimal and hex  values  that  may  also  be
       given for MO.

       dmc_status  [0, 0x0]
              Use  RECEIVE DIAGNOSTIC RESULTS to fetch the Download microcode status dpage and print
              it out.

       dmc_offs  [6, 0x6]
              Download microcode with offsets and activate.

       dmc_offs_save  [7, 0x7]
              Download microcode with offsets, save, and activate.

       dmc_offs_defer  [14, 0xe]
              Download microcode with offsets, save, and defer activate.

       activate_mc  [15, 0xf]
              Activate deferred microcode. There is no follow-up RECEIVE DIAGNOSTIC RESULTS to fetch
              the Download microcode status dpage since the DEVICE might be resetting.

       Apart from dmc_status, these are placed in the Download microcode mode field in the  Download
       microcode  control  dpage.  In  the case of dmc_status the Download microcode status dpage is
       fetched with the RECEIVE DIAGNOSTIC RESULTS command and decoded.

WHEN THE DOWNLOAD FAILS
       Firstly, if it succeeds, this utility should stay silent and return.  Typically vendors  will
       change the "revision" string (which is 4 characters long) whenever they release new firmware.
       That  can  be seen in the response to a SCSI INQUIRY command, for example by using the sg_inq
       utility.  It is possible that the device needs to be power cycled before  the  new  microcode
       becomes active. Also if mode dmc_offs_defer [0xe] is used to download the microcode, then an‐
       other invocation with activate_mc may be needed.

       If  something  goes  wrong, there will typically be messages printed out by this utility. The
       first thing to check is the microcode (firmware) file itself. Is it designed for  the  device
       model;  has  it been corrupted, and if downgrading (i.e. trying to reinstate older firmware),
       does the vendor allow that?

       Getting new firmware on a device is a delicate operation that is not always well  defined  by
       T10's  standards and drafts. One might speculate that they are deliberately vague. In testing
       this utility one vendor's interpretation of the standard was somewhat surprising.  The  --non
       option  was  added to cope with their interpretation. So if the above suggestions don't help,
       try adding the --non option.

NOTES
       This utility can handle a maximum size of 128 MB of microcode which should be sufficient  for
       most  purposes.  In a system that is memory constrained, such large allocations of memory may
       fail.

       The user should be aware that most operating systems have limits on the amount of  data  that
       can  be  sent with one SCSI command. In Linux this depends on the pass through mechanism used
       (e.g. block SG_IO or the sg driver) and various setting in sysfs in the Linux lk 2.6/3 series
       (e.g. /sys/block/sda/queue/max_sectors_kb). Devices (i.e. logical units) also typically  have
       limits  on  the  maximum amount of data they can handle in one command. These two limitations
       suggest that modes containing the word "offset" together with the  --bpw=CS  option  are  re‐
       quired  as  firmware files get larger and larger. And CS can be quite small, for example 4096
       bytes, resulting in many SEND DIAGNOSTIC commands being sent.

       The exact error from the non-standard implementation was a sense key of ILLEGAL  REQUEST  and
       an  asc/ascq code of 0x26,0x0 which is "Invalid field in parameter list". If that is seen try
       again with the --non option.

       Downloading incorrect microcode into a device has the ability to render that device  inopera‐
       ble. One would hope that the device vendor verifies the data before activating it.

       A long (operating system) timeout of 7200 seconds is set on each SEND DIAGNOSTIC command.

       All numbers given with options are assumed to be decimal.  Alternatively numerical values can
       be given in hexadecimal preceded by either "0x" or "0X" (or has a trailing "h" or "H").

EXAMPLES
       If no microcode/firmware file is given then this utility fetches and decodes the Download mi‐
       crocode  status  dpage which could possibly show another initiator in the process of updating
       the microcode. Even if that is happening, fetching the status page should not cause any prob‐
       lems:

         sg_ses_microcode /dev/sg3
       Download microcode status diagnostic page:
         number of secondary sub-enclosures: 0
         generation code: 0x0
          sub-enclosure identifier: 0 [primary]
            download microcode status: No download microcode operation in progress [0x0]
            download microcode additional status: 0x0
            download microcode maximum size: 1048576 bytes
            download microcode expected buffer id: 0x0
            download microcode expected buffer id offset: 0

       The following sends new microcode/firmware to an enclosure. Sending a 1.5 MB file in one com‐
       mand caused the enclosure to lock up temporarily and did not update  the  firmware.  Breaking
       the firmware file into 4 KB chunks (an educated guess) was more successful:

         sg_ses_microcode -b 4k -m dmc_offs_save -I firmware.bin /dev/sg4

       The  firmware update occurred in the following enclosure power cycle. With a modern enclosure
       the Extended Inquiry VPD page gives indications in which situations a firmware  upgrade  will
       take place.

EXIT STATUS
       The  exit  status  of  sg_ses_microcode  is  0  when  it  is  successful.  Otherwise  see the
       sg3_utils(8) man page.

AUTHORS
       Written by Douglas Gilbert.

REPORTING BUGS
       Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT
       Copyright © 2014-2018 Douglas Gilbert
       This software is distributed under a FreeBSD license. There is NO warranty; not even for MER‐
       CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

SEE ALSO
       sg_ses, sg_write_buffer, sg_inq(sg3_utils)

sg3_utils-1.43                              January 2018                         SG_SES_MICROCODE(8)