Get System Interface Capabilities
更新时间： 2026/08/06
在Gitcode上查看源码Get System Interface Capabilities
Change History
| openUBMC Version | Revision Date | Description |
|---|---|---|
| 25.06 | 2025/06/26 | Initial draft: add command details |
Basic Information
Function Description
This command is used to obtain the system interface function.
Privilege
ReadOnly
Command Information
Request Information
| Byte | Data Field |
|---|---|
| NetFn | App 06h |
| CMD | 57h |
| 1 | System Interface Type [7:4]-reserved [3:0]-System Interface Type (For BT use the Get BT Interface Capabilities command) 0h=SSIF 1h=KCS 2h=SMIC all other=reserved |
Response Information
| Byte | Data Field |
|---|---|
| 1 | Completion Code |
| 2 | Reserved, Returned as 00h |
| For System Interface Type=SSIF: | |
| 3 | [7:6]-Transaction support 00b=only single-part reads/writes supported 01b=multi-part reads/writes supported. Start and End transactions only. 10b=multi-part reads/writes supported. Start, Middle, and End transactions supported 11b=reserved [5:4]-reserved [3]-PEC support 1b=implements PEC. BMC will start using PEC in read transactions after it receives any SSIF write transaction that includes a valid PEC. The BMC ceases using PEC if it receives an SSIF write transaction that does not include PEC 0b=does not support PEC. Note that a BMC implementation may reject write transactions that include a PEC byte [2:0]-SSIF Version 000b=version 1 (version defined in this specification) |
| 4 | Input message size in bytes. (1 based) Number of bytes of IPMI message data that the BMC can accept This number does not include slave address, SMBus length, PEC, or SMBus CMD bytes, just the IPMI message data A BMC that just supports single-part writes would return 32 (20h) for this value A BMC that supports multi-part Start and End would return a value from 33 to 64. A BMC that supports multi-part with Middle transactions would return a value from 65 to 255 |
| 5 | Output message size in bytes. (1 based) Maximum number of bytes of IPMI message data that can be read from the BMC. This number does not include slave address, SMBus length, PEC, SMBus CMD bytes, special bytes (such as the special bytes following the length byte in the multi-part read middle and end transactions) just the IPMI message data A BMC that just supports single-part reads would return 20h (32) for this value A BMC that supports multi-part Start and End would return a value from 33 to 62 (the reason this is 62 instead of 64 is that there are two special bytes after the length byte.) A BMC that supports multi-part with Middle transactions would return a value from 63 to 255 |
| For System Interface Type=KCS or SMIC | |
| 3 | [7:3]-reserved [2:0]-System Interface Version 000b=version 1 (conformant with KCS or SMIC interface as defined in this specification) |
| 4 | Input maximum message size in bytes. (1 based) Largest number of bytes that can be transferred in a KCS FFh means 255 or more |
Command Example
Obtain the system interface function.
Request:
bash
ipmicmd -k "0f 00 06 57 01" smi 0Response:
text
0f 07 00 57 00 00 00 28