Artesyn ATCA-9305 User's Manual (May 2014) - Manual (Page 146)

System Management
ATCA-9305 User’s Manual (10009109-07) 146
2. The BMR-H8S-AMCc returns its IPMB address in the Get Address Info reply. In this example,
72
16
is the IPMB-0 address of the IPMC.
{B4 00 01 00 00 FF 72 FF 00 01 07]
3. The payload software composes a Get Address Info command requesting the responder to
provide its addressing information for FRU device 0. The request is composed in the IPMB
format. The responder address is set to 20
16 (for the shelf manager). The requester
address is set to the value obtained in the previous step.
{20 B0 30 72 00 01 00 8D]
4. The payload software forwards the command composed in the previous step to the shelf
manager using the Send Message command. The Send/Get Message in SIPL format is:
[18 xx 34 40 20 B0 30 72 00 01 00 8D]
5. The BMR-H8S-AMCc firmware sends the Get Address Info request to the shelf manager,
waits for a reply to this request, and sends this reply to the payload software in the
Send/Get Message response.
[1C 00 34 00 72 B4 DA 20 00 01 00 00 41 82 FF 00 FF 00 1E]
6. The payload software extracts the Get Address info reply from the Send/Get Message
response and retrieves the physical address of the board from it.
The second message bridging implementation, bridging via LUN 10, allows the payload to
receive responses to requests sent to IPMB-0 via the Send Message command with request
tracking disabled, as well as receive requests from IPMB-0. To provide this functionality, the
ATCA-9305 IPMC places all messages coming to LUN 10 from IPMB-0 in a dedicated Receive
Message Queue, and those messages are processed by the payload instead of the IPMC
firmware. To read messages from the Receive Message Queue, the payload software uses the
standard Get Message command. The payload software is notified about messages coming to
LUN 10 via the Get Status command of the SIPL protocol and the payload notification
mechanism, or, if the LPC/KCS-based Payload Interface is used, using the KCS interrupt. The
Receive Message Queue of the ATCA-9305 IPMC is limited to 128 bytes, which is sufficient for
storing at least three IPMB messages, but may be not enough for a larger number of messages.
Taking this into account, the payload software must read messages from the queue as fast as
possible, caching them on the on-carrier payload side for further handling, if it is necessary. If
the Receive Message Queue is full, the ATCA-9305 IPMC rejects all requests coming to LUN 10
with the C0h (Node Busy) completion code and discards all responses coming to this LUN.