| What: /dev/raw-kcs* |
| Date: 2021-02-15 |
| KernelVersion: 5.13 |
| Contact: openbmc@lists.ozlabs.org |
| Contact: openipmi-developer@lists.sourceforge.net |
| Contact: Andrew Jeffery <andrew@aj.id.au> |
| Description: ``/dev/raw-kcs*`` exposes to userspace the data and |
| status registers of Keyboard-Controller-Style (KCS) IPMI |
| interfaces via read() and write() syscalls. Direct |
| exposure of the data and status registers enables |
| inefficient but arbitrary protocols to be implemented |
| over the device. A typical approach is to use KCS |
| devices for out-of-band signalling for bulk data |
| transfers over other interfaces between a Baseboard |
| Management Controller and its host. |
| |
| +--------+--------+---------+ |
| | Offset | read() | write() | |
| +--------+--------+---------+ |
| | 0 | IDR | ODR | |
| +--------+--------+---------+ |
| | 1 | STR | STR | |
| +--------+--------+---------+ |
| |
| Users: libmctp: https://github.com/openbmc/libmctp |
