Datasheet

Intel
®
Xeon
®
Processor C5500/C3500 Series
February 2010 Datasheet, Volume 1
Order Number: 323103-001 85
Interfaces
The 4-byte data response defined above is sent in standard PECI ordering with LSB first
and MSB last.
2.2.2.9 Mailbox Usage Definition
2.2.2.9.1 Acquiring the Mailbox
The MbxSend() command is used to acquire control of the PECI mailbox and issue
information regarding the specific request. The completion code response indicates
whether or not the originator has acquired a lock on the mailbox, and that completion
code always specifies the Transaction ID associated with that lock (see
Section 2.2.2.9.2).
Once a mailbox has been acquired by an originating agent, future requests to acquire
that mailbox will be denied with an ‘interface busy’ completion code response.
The lock on a mailbox is not achieved until the last bit of the MbxSend() Read FCS is
transferred (in other words, it is not committed until the command completes). If the
host aborts the command at any time prior to that bit transmission, the mailbox lock
will be lost and it will remain available for any other agent to take control.
Figure 28. MbxGet()
Response Data[31:0]
Byte #
Byte
Definition
0
Client Address
1
Write Length
0x02
2
Read Length
0x05
10
FCS
3
Cmd Code
0xd5
11
Completion
Code
5 6
LSB
MSB
5 64
Transaction ID
10 115 68 97 10
FCS
11
Table 39. MbxGet() Response Definition
Response Meaning
Aborted Write FCS Response data is not ready. Command retry is appropriate.
CC: 0x40 Command passed, data is valid.
CC: 0x80
Error causing a response timeout. Either due to a rare, internal timing condition or a
processor RESET condition or processor S1 state. Retry is appropriate outside of the
RESET or S1 states.
CC: 0x81 Thermal configuration data was malformed or exceeded limits.
CC: 0x82 Thermal status mask is illegal.
CC: 0x83 Invalid counter select.
CC: 0x84 Invalid Machine Check Bank or Index.
CC: 0x85 Failure due to lack of Mailbox lock or invalid Transaction ID.
CC: 0x86 Mailbox interface is unavailable or busy.
CC: 0xFF Unknown/Invalid Mailbox Request.