Datasheet

Interfaces
Intel
®
Xeon
®
Processor C5500/C3500 Series
Datasheet, Volume 1 February 2010
74 Order Number: 323103-001
Example bus transaction for a thermal sensor device located at address 0x30 returning
a value of negative 10° C:
2.2.2.3.2 Supported Responses
The typical client response is a passing FCS and good thermal data. Under some
conditions, the client’s response will indicate a failure.
2.2.2.4 PCIConfigRd()
The PCIConfigRd() command gives sideband read access to the entire PCI configuration
space maintained in the processor, but the PECI commands do not suport the IIO PCI
space. This capability does not include support for route-through to downstream
devices or sibling processors. Intel
®
Xeon
®
processor C5500/C3500 series PECI
originators may conduct a device/function/register enumeration sweep of this space by
issuing reads in the same manner that BIOS would. A response of all 1’s indicates that
the device/function/register is unimplemented.
PCI configuration addresses are constructed as shown in the following diagram. Under
normal in-band procedures, the Bus number (including any reserved bits) would be
used to direct a read or write to the proper device. Since there is a one-to-one mapping
between any given client address and the bus number, any request made with a bad
Bus number is ignored and the client will respond with a ‘pass’ completion code but all
0’s in the data. The bus number for the processor PCI registers will be programmed to
Figure 17. GetTemp()
Byte #
Byte
Definition
0
Client Address
1
Write Length
0x01
2
Read Length
0x02
4
FCS
5
Temp[7:0]
6
Temp[15:8]
7
FCS
3
Cmd Code
0x01
Figure 18. GetTemp() Example
Byte #
Byte
Definition
0
0x30
1
0x01
2
0x02
4
0xef
5
0x80
6
0xfd
7
0x4b
3
0x01
Table 30. GetTemp() Response Definition
Response Meaning
General Sensor Error (GSE) Thermal scan did not complete in time. Retry is appropriate.
0x0000 Processor is running at its maximum temperature or is currently being reset.
All other data Valid temperature reading, reported as a negative offset from the TCC
activation temperature.