Datasheet
Intel
®
Xeon
®
Processor C5500/C3500 Series
February 2010 Datasheet, Volume 1
Order Number: 323103-001 83
Interfaces
Because a particular MbxSend() command may specify an update to potentially critical
registers inside the processor, it includes an Assured Write FCS (AW FCS) byte as part
of the write data payload. See the RS - Platform Environment Control Interface (PECI)
Specification, Revision 2.0 for a definition of the AW FCS protocol. In the event that the
AW FCS mismatches with the client-calculated FCS, the client will abort the write and
will always respond with a bad Write FCS.
2.2.2.7.2 Command Format
The MbxSend() format is as follows:
Write Length: 7
Read Length: 1
Command: 0xd1
Multi-Domain Support: Yes (see Table 41)
Description: Deposits the Request Type and associated 4-byte data in the Mailbox
interface and returns a completion code byte with the details of the execution results.
See Section 2.2.4.2 for completion code definitions.
Figure 26. MbxSend() Command Data Format
Byte #
Byte
Definition
0
Request Type
1
Data[31:0]
234
Figure 27. MbxSend()
Byte #
Byte
Definition
0
Client Address
1
Write Length
0x07
2
Read Length
0x01
10
FCS
3
Cmd Code
0xd1
11
Completion
Code
12
FCS
5 6 7 8
LSB MSBData[31:0]
10 119
AW FCS
4
Request Type