1.. _mcumgr_smp_group_0:
2
3Default/OS Management Group
4###########################
5
6OS management group defines following commands:
7
8.. table::
9    :align: center
10
11    +-------------------+-----------------------------------------------+
12    | ``Command ID``    | Command description                           |
13    +===================+===============================================+
14    | ``0``             | Echo                                          |
15    +-------------------+-----------------------------------------------+
16    | ``1``             | Console/Terminal echo control;                |
17    |                   | unimplemented by Zephyr                       |
18    +-------------------+-----------------------------------------------+
19    | ``2``             | Task Statistics                               |
20    +-------------------+-----------------------------------------------+
21    | ``3``             | Memory pool statistics                        |
22    +-------------------+-----------------------------------------------+
23    | ``4``             | Date-time string                              |
24    +-------------------+-----------------------------------------------+
25    | ``5``             | System reset                                  |
26    +-------------------+-----------------------------------------------+
27    | ``6``             | MCUMGR parameters                             |
28    +-------------------+-----------------------------------------------+
29    | ``7``             | OS/Application info                           |
30    +-------------------+-----------------------------------------------+
31    | ``8``             | Bootloader information                        |
32    +-------------------+-----------------------------------------------+
33
34Echo command
35************
36
37Echo command responses by sending back string that it has received.
38
39Echo request
40============
41
42Echo request header fields:
43
44.. table::
45    :align: center
46
47    +--------------------+--------------+----------------+
48    | ``OP``             | ``Group ID`` | ``Command ID`` |
49    +====================+==============+================+
50    | ``0`` or ``2``     | ``0``        |  ``0``         |
51    +--------------------+--------------+----------------+
52
53CBOR data of request:
54
55.. code-block:: none
56
57    {
58        (str)"d" : (str)
59    }
60
61where:
62
63.. table::
64    :align: center
65
66    +-----------------------+---------------------------------------------------+
67    | "d"                   | string to be replied by echo service.             |
68    +-----------------------+---------------------------------------------------+
69
70Echo response
71=============
72
73Echo response header fields:
74
75.. table::
76    :align: center
77
78    +--------+--------------+----------------+----------------------------------+
79    | ``OP`` | ``Group ID`` | ``Command ID`` | Note                             |
80    +========+==============+================+==================================+
81    | ``1``  | ``0``        |  ``0``         | When request ``OP`` was ``0``    |
82    +--------+--------------+----------------+----------------------------------+
83    | ``3``  | ``0``        |  ``0``         | When request ``OP`` was ``2``    |
84    +--------+--------------+----------------+----------------------------------+
85
86CBOR data of successful response:
87
88.. code-block:: none
89
90    {
91        (str)"r"        : (str)
92    }
93
94In case of error the CBOR data takes the form:
95
96.. tabs::
97
98   .. group-tab:: SMP version 2
99
100      .. code-block:: none
101
102          {
103              (str)"err" : {
104                  (str)"group"    : (uint)
105                  (str)"rc"       : (uint)
106              }
107          }
108
109   .. group-tab:: SMP version 1 (and non-group SMP version 2)
110
111      .. code-block:: none
112
113          {
114              (str)"rc"       : (int)
115          }
116
117where:
118
119.. table::
120    :align: center
121
122    +------------------+-------------------------------------------------------------------------+
123    | "r"              | replying echo string.                                                   |
124    +------------------+-------------------------------------------------------------------------+
125    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
126    |                  | appears if an error is returned when using SMP version 2.               |
127    +------------------+-------------------------------------------------------------------------+
128    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
129    |                  | non-zero (error condition) when using SMP version 2.                    |
130    +------------------+-------------------------------------------------------------------------+
131    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
132    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
133    +------------------+-------------------------------------------------------------------------+
134
135Task statistics command
136***********************
137
138The command responds with some system statistics.
139
140Task statistics request
141=======================
142
143Task statistics request header fields:
144
145.. table::
146    :align: center
147
148    +--------+--------------+----------------+
149    | ``OP`` | ``Group ID`` | ``Command ID`` |
150    +========+==============+================+
151    | ``0``  | ``0``        |  ``2``         |
152    +--------+--------------+----------------+
153
154The command sends an empty CBOR map as data.
155
156
157Task statistics response
158========================
159
160Task statistics response header fields:
161
162.. table::
163    :align: center
164
165    +--------+--------------+----------------+
166    | ``OP`` | ``Group ID`` | ``Command ID`` |
167    +========+==============+================+
168    | ``1``  | ``0``        |  ``2``         |
169    +--------+--------------+----------------+
170
171CBOR data of successful response:
172
173.. code-block:: none
174
175    {
176        (str)"tasks" : {
177            (str)<task_name> : {
178                (str)"prio"         : (uint)
179                (str)"tid"          : (uint)
180                (str)"state"        : (uint)
181                (str)"stkuse"       : (uint)
182                (str)"stksiz"       : (uint)
183                (str)"cswcnt"       : (uint)
184                (str)"runtime"      : (uint)
185                (str)"last_checkin" : (uint)
186                (str)"next_checkin" : (uint)
187            }
188            ...
189        }
190    }
191
192In case of error the CBOR data takes the form:
193
194.. tabs::
195
196   .. group-tab:: SMP version 2
197
198      .. code-block:: none
199
200          {
201              (str)"err" : {
202                  (str)"group"    : (uint)
203                  (str)"rc"       : (uint)
204              }
205          }
206
207   .. group-tab:: SMP version 1 (and non-group SMP version 2)
208
209      .. code-block:: none
210
211          {
212              (str)"rc"       : (int)
213          }
214
215where:
216
217.. table::
218    :align: center
219
220    +------------------+-------------------------------------------------------------------------+
221    | <task_name>      | string identifying task.                                                |
222    +------------------+-------------------------------------------------------------------------+
223    | "prio"           | task priority.                                                          |
224    +------------------+-------------------------------------------------------------------------+
225    | "tid"            | numeric task ID.                                                        |
226    +------------------+-------------------------------------------------------------------------+
227    | "state"          | numeric task state.                                                     |
228    +------------------+-------------------------------------------------------------------------+
229    | "stkuse"         | task's/thread's stack usage.                                            |
230    +------------------+-------------------------------------------------------------------------+
231    | "stksiz"         | task's/thread's stack size.                                             |
232    +------------------+-------------------------------------------------------------------------+
233    | "cswcnt"         | task's/thread's context switches.                                       |
234    +------------------+-------------------------------------------------------------------------+
235    | "runtime"        | task's/thread's runtime in "ticks".                                     |
236    +------------------+-------------------------------------------------------------------------+
237    | "last_checkin"   | set to 0 by Zephyr.                                                     |
238    +------------------+-------------------------------------------------------------------------+
239    | "next_checkin"   | set to 0 by Zephyr.                                                     |
240    +------------------+-------------------------------------------------------------------------+
241    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
242    |                  | appears if an error is returned when using SMP version 2.               |
243    +------------------+-------------------------------------------------------------------------+
244    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
245    |                  | non-zero (error condition) when using SMP version 2.                    |
246    +------------------+-------------------------------------------------------------------------+
247    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
248    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
249    +------------------+-------------------------------------------------------------------------+
250
251.. note::
252    The unit for "stkuse" and "stksiz" is system dependent and in case of Zephyr
253    this is number of 4 byte words.
254
255Memory pool statistics
256**********************
257
258The command is used to obtain information on memory pools active in running
259system.
260
261Memory pool statistic request
262=============================
263
264Memory pool statistics request header fields:
265
266.. table::
267    :align: center
268
269    +--------+--------------+----------------+
270    | ``OP`` | ``Group ID`` | ``Command ID`` |
271    +========+==============+================+
272    | ``0``  | ``0``        |  ``3``         |
273    +--------+--------------+----------------+
274
275The command sends an empty CBOR map as data.
276
277Memory pool statistics response
278===============================
279
280Memory pool statistics response header fields:
281
282.. table::
283    :align: center
284
285    +--------+--------------+----------------+
286    | ``OP`` | ``Group ID`` | ``Command ID`` |
287    +========+==============+================+
288    | ``1``  | ``0``        |  ``3``         |
289    +--------+--------------+----------------+
290
291CBOR data of successful response:
292
293.. code-block:: none
294
295    {
296        (str)<pool_name> {
297            (str)"blksiz"   : (int)
298            (str)"nblks"    : (int)
299            (str)"nfree"    : (int)
300            (str)"min'      : (int)
301        }
302        ...
303    }
304
305In case of error the CBOR data takes the form:
306
307.. tabs::
308
309   .. group-tab:: SMP version 2
310
311      .. code-block:: none
312
313          {
314              (str)"err" : {
315                  (str)"group"    : (uint)
316                  (str)"rc"       : (uint)
317              }
318          }
319
320   .. group-tab:: SMP version 1 (and non-group SMP version 2)
321
322      .. code-block:: none
323
324          {
325              (str)"rc"       : (int)
326          }
327
328where:
329
330.. table::
331    :align: center
332
333    +------------------+-------------------------------------------------------------------------+
334    | <pool_name>      | string representing the pool name, used as a key for dictionary with    |
335    |                  | pool statistics data.                                                   |
336    +------------------+-------------------------------------------------------------------------+
337    | "blksiz"         | size of the memory block in the pool.                                   |
338    +------------------+-------------------------------------------------------------------------+
339    | "nblks"          | number of blocks in the pool.                                           |
340    +------------------+-------------------------------------------------------------------------+
341    | "nfree"          | number of free blocks.                                                  |
342    +------------------+-------------------------------------------------------------------------+
343    | "min"            | lowest number of free blocks the pool reached during run-time.          |
344    +------------------+-------------------------------------------------------------------------+
345    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
346    |                  | appears if an error is returned when using SMP version 2.               |
347    +------------------+-------------------------------------------------------------------------+
348    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
349    |                  | non-zero (error condition) when using SMP version 2.                    |
350    +------------------+-------------------------------------------------------------------------+
351    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
352    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
353    +------------------+-------------------------------------------------------------------------+
354
355Date-time command
356*****************
357
358The command allows to obtain string representing current time-date on a device
359or set a new time to a device.
360The time format used, by both set and get operations, is:
361
362    "yyyy-MM-dd'T'HH:mm:ss.SSSSSSZZZZZ"
363
364Date-time get
365=============
366
367The command allows to obtain date-time from a device.
368
369Date-time get request
370---------------------
371
372Date-time request header fields:
373
374.. table::
375    :align: center
376
377    +--------+--------------+----------------+
378    | ``OP`` | ``Group ID`` | ``Command ID`` |
379    +========+==============+================+
380    | ``0``  | ``0``        |  ``4``         |
381    +--------+--------------+----------------+
382
383The command sends an empty CBOR map as data.
384
385Date-time get response
386----------------------
387
388Date-time get response header fields:
389
390.. table::
391    :align: center
392
393    +--------+--------------+----------------+
394    | ``OP`` | ``Group ID`` | ``Command ID`` |
395    +========+==============+================+
396    | ``1``  | ``0``        |  ``4``         |
397    +--------+--------------+----------------+
398
399CBOR data of successful response:
400
401.. code-block:: none
402
403    {
404        (str)"datetime" : (str)
405    }
406
407In case of error the CBOR data takes the form:
408
409.. tabs::
410
411   .. group-tab:: SMP version 2
412
413      .. code-block:: none
414
415          {
416              (str)"err" : {
417                  (str)"group"    : (uint)
418                  (str)"rc"       : (uint)
419              }
420          }
421
422   .. group-tab:: SMP version 1 (and non-group SMP version 2)
423
424      .. code-block:: none
425
426          {
427              (str)"rc"       : (int)
428          }
429
430where:
431
432.. table::
433    :align: center
434
435    +------------------+-------------------------------------------------------------------------+
436    | "datetime"       | String in format: ``yyyy-MM-dd'T'HH:mm:ss.SSSSSSZZZZZ``.                |
437    +------------------+-------------------------------------------------------------------------+
438    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
439    |                  | appears if an error is returned when using SMP version 2.               |
440    +------------------+-------------------------------------------------------------------------+
441    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
442    |                  | non-zero (error condition) when using SMP version 2.                    |
443    +------------------+-------------------------------------------------------------------------+
444    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
445    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
446    +------------------+-------------------------------------------------------------------------+
447
448
449Date-time set
450=============
451
452The command allows to set date-time to a device.
453
454Date-time set request
455---------------------
456
457Date-time set request header fields:
458
459.. table::
460    :align: center
461
462    +--------+--------------+----------------+
463    | ``OP`` | ``Group ID`` | ``Command ID`` |
464    +========+==============+================+
465    | ``2``  | ``0``        |  ``4``         |
466    +--------+--------------+----------------+
467
468CBOR data of response:
469
470.. code-block:: none
471
472    {
473        (str)"datetime" : (str)
474    }
475
476where:
477
478.. table::
479    :align: center
480
481    +---------------+----------------------------------------------------------+
482    | "datetime"    | String in format: ``yyyy-MM-dd'T'HH:mm:ss.SSSSSSZZZZZ``. |
483    +---------------+----------------------------------------------------------+
484
485Date-time set response
486----------------------
487
488Date-time set response header fields:
489
490.. table::
491    :align: center
492
493    +--------+--------------+----------------+
494    | ``OP`` | ``Group ID`` | ``Command ID`` |
495    +========+==============+================+
496    | ``3``  | ``0``        |  ``4``         |
497    +--------+--------------+----------------+
498
499The command sends an empty CBOR map as data if successful. In case of error the
500CBOR data takes the form:
501
502.. tabs::
503
504   .. group-tab:: SMP version 2
505
506      .. code-block:: none
507
508          {
509              (str)"err" : {
510                  (str)"group"    : (uint)
511                  (str)"rc"       : (uint)
512              }
513          }
514
515   .. group-tab:: SMP version 1 (and non-group SMP version 2)
516
517      .. code-block:: none
518
519          {
520              (str)"rc"       : (int)
521          }
522
523where:
524
525.. table::
526    :align: center
527
528    +------------------+-------------------------------------------------------------------------+
529    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
530    |                  | appears if an error is returned when using SMP version 2.               |
531    +------------------+-------------------------------------------------------------------------+
532    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
533    |                  | non-zero (error condition) when using SMP version 2.                    |
534    +------------------+-------------------------------------------------------------------------+
535    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
536    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
537    +------------------+-------------------------------------------------------------------------+
538
539System reset
540************
541
542Performs reset of system. The device should issue response before resetting so
543that the SMP client could receive information that the command has been
544accepted. By default, this command is accepted in all conditions, however if
545the :kconfig:option:`CONFIG_MCUMGR_GRP_OS_RESET_HOOK` is enabled and an
546application registers a callback, the callback will be called when this command
547is issued and can be used to perform any necessary tidy operations prior to the
548module rebooting, or to reject the reset request outright altogether with an
549error response. For details on this functionality, see `ref:`mcumgr_callbacks`.
550
551System reset request
552====================
553
554System reset request header fields:
555
556.. table::
557    :align: center
558
559    +--------+--------------+----------------+
560    | ``OP`` | ``Group ID`` | ``Command ID`` |
561    +========+==============+================+
562    | ``2``  | ``0``        |  ``5``         |
563    +--------+--------------+----------------+
564
565Normally the command sends an empty CBOR map as data, but if a previous reset
566attempt has responded with "rc" equal to :c:enum:`MGMT_ERR_EBUSY` then the
567following map may be sent to force a reset:
568
569.. code-block:: none
570
571    {
572        (opt)"force"       : (int)
573    }
574
575where:
576
577.. table::
578    :align: center
579
580    +-----------------------+---------------------------------------------------+
581    | "force"               | Force reset if value > 0, optional if 0.          |
582    +-----------------------+---------------------------------------------------+
583
584
585System reset response
586=====================
587
588System reset response header fields
589
590.. table::
591    :align: center
592
593    +--------+--------------+----------------+
594    | ``OP`` | ``Group ID`` | ``Command ID`` |
595    +========+==============+================+
596    | ``3``  | ``0``        |  ``5``         |
597    +--------+--------------+----------------+
598
599The command sends an empty CBOR map as data if successful. In case of error the
600CBOR data takes the form:
601
602.. tabs::
603
604   .. group-tab:: SMP version 2
605
606      .. code-block:: none
607
608          {
609              (str)"err" : {
610                  (str)"group"    : (uint)
611                  (str)"rc"       : (uint)
612              }
613          }
614
615   .. group-tab:: SMP version 1 (and non-group SMP version 2)
616
617      .. code-block:: none
618
619          {
620              (str)"rc"       : (int)
621          }
622
623where:
624
625.. table::
626    :align: center
627
628    +------------------+-------------------------------------------------------------------------+
629    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
630    |                  | appears if an error is returned when using SMP version 2.               |
631    +------------------+-------------------------------------------------------------------------+
632    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
633    |                  | non-zero (error condition) when using SMP version 2.                    |
634    +------------------+-------------------------------------------------------------------------+
635    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
636    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
637    +------------------+-------------------------------------------------------------------------+
638
639MCUmgr Parameters
640*****************
641
642Used to obtain parameters of mcumgr library.
643
644MCUmgr Parameters Request
645=========================
646
647MCUmgr parameters request header fields:
648
649.. table::
650    :align: center
651
652    +--------+--------------+----------------+
653    | ``OP`` | ``Group ID`` | ``Command ID`` |
654    +========+==============+================+
655    | ``0``  | ``0``        |  ``6``         |
656    +--------+--------------+----------------+
657
658The command sends an empty CBOR map as data.
659
660MCUmgr Parameters Response
661==========================
662
663MCUmgr parameters response header fields
664
665.. table::
666    :align: center
667
668    +--------+--------------+----------------+
669    | ``OP`` | ``Group ID`` | ``Command ID`` |
670    +========+==============+================+
671    | ``1``  | ``0``        |  ``6``         |
672    +--------+--------------+----------------+
673
674CBOR data of successful response:
675
676.. code-block:: none
677
678    {
679        (str)"buf_size"     : (uint)
680        (str)"buf_count"    : (uint)
681    }
682
683In case of error the CBOR data takes the form:
684
685.. tabs::
686
687   .. group-tab:: SMP version 2
688
689      .. code-block:: none
690
691          {
692              (str)"err" : {
693                  (str)"group"    : (uint)
694                  (str)"rc"       : (uint)
695              }
696          }
697
698   .. group-tab:: SMP version 1 (and non-group SMP version 2)
699
700      .. code-block:: none
701
702          {
703              (str)"rc"       : (int)
704          }
705
706where:
707
708.. table::
709    :align: center
710
711    +------------------+-------------------------------------------------------------------------+
712    | "buf_size"       | Single SMP buffer size, this includes SMP header and CBOR payload.      |
713    +------------------+-------------------------------------------------------------------------+
714    | "buf_count"      | Number of SMP buffers supported.                                        |
715    +------------------+-------------------------------------------------------------------------+
716    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
717    |                  | appears if an error is returned when using SMP version 2.               |
718    +------------------+-------------------------------------------------------------------------+
719    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
720    |                  | non-zero (error condition) when using SMP version 2.                    |
721    +------------------+-------------------------------------------------------------------------+
722    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
723    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
724    +------------------+-------------------------------------------------------------------------+
725
726.. _mcumgr_os_application_info:
727
728OS/Application Info
729*******************
730
731Used to obtain information on running image, similar functionality to the linux
732uname command, allowing details such as kernel name, kernel version, build
733date/time, processor type and application-defined details to be returned. This
734functionality can be enabled with :kconfig:option:`CONFIG_MCUMGR_GRP_OS_INFO`.
735
736OS/Application Info Request
737===========================
738
739OS/Application info request header fields:
740
741.. table::
742    :align: center
743
744    +--------+--------------+----------------+
745    | ``OP`` | ``Group ID`` | ``Command ID`` |
746    +========+==============+================+
747    | ``0``  | ``0``        |  ``7``         |
748    +--------+--------------+----------------+
749
750CBOR data of request:
751
752.. code-block:: none
753
754    {
755        (str,opt)"format"      : (str)
756    }
757
758where:
759
760.. table::
761    :align: center
762
763    +----------+-------------------------------------------------------------------+
764    | "format" | Format specifier of returned response, fields are appended in     |
765    |          | their natural ascending index order, not the order of             |
766    |          | characters that are received by the command. Format               |
767    |          | specifiers: |br|                                                  |
768    |          | * ``s`` Kernel name |br|                                          |
769    |          | * ``n`` Node name |br|                                            |
770    |          | * ``r`` Kernel release |br|                                       |
771    |          | * ``v`` Kernel version |br|                                       |
772    |          | * ``b`` Build date and time (requires                             |
773    |          | :kconfig:option:`CONFIG_MCUMGR_GRP_OS_INFO_BUILD_DATE_TIME`) |br| |
774    |          | * ``m`` Machine |br|                                              |
775    |          | * ``p`` Processor |br|                                            |
776    |          | * ``i`` Hardware platform |br|                                    |
777    |          | * ``o`` Operating system |br|                                     |
778    |          | * ``a`` All fields (shorthand for all above options) |br|         |
779    |          | If this option is not provided, the ``s`` Kernel name option      |
780    |          | will be used.                                                     |
781    +----------+-------------------------------------------------------------------+
782
783OS/Application Info Response
784============================
785
786OS/Application info response header fields
787
788.. table::
789    :align: center
790
791    +--------+--------------+----------------+
792    | ``OP`` | ``Group ID`` | ``Command ID`` |
793    +========+==============+================+
794    | ``1``  | ``0``        |  ``7``         |
795    +--------+--------------+----------------+
796
797CBOR data of successful response:
798
799.. code-block:: none
800
801    {
802        (str)"output"       : (str)
803    }
804
805In case of error the CBOR data takes the form:
806
807.. tabs::
808
809   .. group-tab:: SMP version 2
810
811      .. code-block:: none
812
813          {
814              (str)"err" : {
815                  (str)"group"    : (uint)
816                  (str)"rc"       : (uint)
817              }
818          }
819
820   .. group-tab:: SMP version 1 (and non-group SMP version 2)
821
822      .. code-block:: none
823
824          {
825              (str)"rc"       : (int)
826          }
827
828where:
829
830.. table::
831    :align: center
832
833    +------------------+-------------------------------------------------------------------------+
834    | "output"         | Text response including requested parameters.                           |
835    +------------------+-------------------------------------------------------------------------+
836    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
837    |                  | appears if an error is returned when using SMP version 2.               |
838    +------------------+-------------------------------------------------------------------------+
839    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
840    |                  | non-zero (error condition) when using SMP version 2.                    |
841    +------------------+-------------------------------------------------------------------------+
842    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
843    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
844    +------------------+-------------------------------------------------------------------------+
845
846Bootloader Information
847**********************
848
849Allows retrieving information about the on-board bootloader and its parameters.
850
851Bootloader Information Request
852==============================
853
854Bootloader information request header:
855
856.. table::
857    :align: center
858
859    +--------+--------------+----------------+
860    | ``OP`` | ``Group ID`` | ``Command ID`` |
861    +========+==============+================+
862    | ``0``  | ``0``        |  ``8``         |
863    +--------+--------------+----------------+
864
865CBOR data of request:
866
867.. code-block:: none
868
869    {
870        (str,opt)"query"  : (str)
871    }
872
873where:
874
875.. table::
876    :align: center
877
878    +--------------+-----------------------------------------------+
879    | "query"      | Is string representing query for parameters,  |
880    |              | with no restrictions how the query looks like |
881    |              | as processing of query is left for bootloader |
882    |              | backend.                                      |
883    |              | If there is no query, then response will      |
884    |              | return string identifying the bootloader.     |
885    +--------------+-----------------------------------------------+
886
887Bootloader Information Response
888===============================
889
890Bootloader information response header:
891
892.. table::
893    :align: center
894
895    +--------+--------------+----------------+
896    | ``OP`` | ``Group ID`` | ``Command ID`` |
897    +========+==============+================+
898    | ``1``  | ``0``        |  ``8``         |
899    +--------+--------------+----------------+
900
901In case when no "query" has been provided in request,
902CBOR data of response:
903
904.. code-block:: none
905
906    {
907        (str)"bootloader"      : (str)
908    }
909
910where:
911
912.. table::
913    :align: center
914
915    +--------------+-----------------------------------------------+
916    | "bootloader" | String representing bootloader name           |
917    +--------------+-----------------------------------------------+
918
919In case when "query" is provided:
920
921.. code-block:: none
922
923    {
924        (str,opt)<response>   : ()
925	...
926    }
927
928where:
929
930.. table::
931    :align: center
932
933    +------------------+-------------------------------------------------------------------------+
934    | <response>       | Response to "query". This is optional and may be left out in case when  |
935    |                  | query yields no response, SMP version 2 error code of                   |
936    |                  | `OS_MGMT_ERR_QUERY_YIELDS_NO_ANSWER` is expected.                       |
937    |                  | Response may have more than one parameter reported back or it may be    |
938    |                  | a map, that is dependent on bootloader backednd and query.              |
939    +------------------+-------------------------------------------------------------------------+
940    | ...              | Parameter characteristic information.                                   |
941    +------------------+-------------------------------------------------------------------------+
942
943Parameter may be accompanied by additional, parameter specific, information keywords with
944assigned values.
945
946In case of error the CBOR data takes the form:
947
948.. tabs::
949
950   .. group-tab:: SMP version 2
951
952      .. code-block:: none
953
954          {
955              (str)"err" : {
956                  (str)"group"    : (uint)
957                  (str)"rc"       : (uint)
958              }
959          }
960
961   .. group-tab:: SMP version 1 (and non-group SMP version 2)
962
963      .. code-block:: none
964
965          {
966              (str)"rc"       : (int)
967          }
968
969where:
970
971.. table::
972    :align: center
973
974    +------------------+-------------------------------------------------------------------------+
975    | "err" -> "group" | :c:enum:`mcumgr_group_t` group of the group-based error code. Only      |
976    |                  | appears if an error is returned when using SMP version 2.               |
977    +------------------+-------------------------------------------------------------------------+
978    | "err" -> "rc"    | contains the index of the group-based error code. Only appears if       |
979    |                  | non-zero (error condition) when using SMP version 2.                    |
980    +------------------+-------------------------------------------------------------------------+
981    | "rc"             | :c:enum:`mcumgr_err_t` only appears if non-zero (error condition) when  |
982    |                  | using SMP version 1 or for SMP errors when using SMP version 2.         |
983    +------------------+-------------------------------------------------------------------------+
984
985Bootloader Information: MCUboot
986===============================
987
988In case when MCUboot is application bootloader, empty request will
989be responded with:
990
991.. code-block:: none
992
993    {
994        (str)"bootloader"      : (str)"MCUboot"
995    }
996
997Currently "MCUboot" supports querying for mode of operation:
998
999.. code-block:: none
1000
1001    {
1002        (str)"query"           : (str)"mode"
1003    }
1004
1005Response to "mode" is:
1006
1007.. code-block:: none
1008
1009    {
1010        (str)"mode"                     : (int)
1011        (str,opt)"no-downgrade"         : (bool)
1012    }
1013
1014where "mode" is one of:
1015
1016.. table::
1017    :align: center
1018
1019    +-----+-----------------------------------------------------+
1020    | -1  | Unknown mode of MCUboot.                            |
1021    +-----+-----------------------------------------------------+
1022    |  0  | MCUboot is in single application mode.              |
1023    +-----+-----------------------------------------------------+
1024    |  1  | MCUboot is in swap using scratch partition mode.    |
1025    +-----+-----------------------------------------------------+
1026    |  2  | MCUboot is in overwrite (upgrade-only) mode.        |
1027    +-----+-----------------------------------------------------+
1028    |  3  | MCUboot is in swap without scratch mode.            |
1029    +-----+-----------------------------------------------------+
1030    |  4  | MCUboot is in DirectXIP without revert mode.        |
1031    +-----+-----------------------------------------------------+
1032    |  5  | MCUboot is in DirectXIP with revert mode.           |
1033    +-----+-----------------------------------------------------+
1034    |  6  | MCUboot is in RAM loader mode.                      |
1035    +-----+-----------------------------------------------------+
1036
1037The ``no-downgrade`` field is a flag, which is always sent when true, indicating that MCUboot has
1038downgrade prevention enabled; downgrade prevention means that if the uploaded image has a lower
1039version than the currently running application, it will not be used for an update by MCUboot.
1040
1041MCUmgr may reject images with a lower version in this configuration.
1042