Intel E5-1600, E5-4600 manual Caching Agent TOR Read, Thermal Margin Read, Read Mode bit 11 = ‘0’

2.5.2.6.30Caching Agent TOR Read

This feature allows the PECI host to read the Caching Agent (Cbo) Table of Requests (TOR). This information is useful for debug in the event of a 3-strike timeout that results in a processor IERR assertion. The 16-bit parameter field is used to specify the Cbo index, TOR array index and bank number according to the following bit assignments.

•Bits [1:0] - Bank Number - legal values from 0 to 2

•Bits [6:2] - TOR Array Index - legal values from 0 to 19

•Bits [10:7] - Cbo Index - legal values from 0 to 7

•Bit [11] - Read Mode - should be set to ‘0’ for TOR reads

•Bits [15:12] - Reserved

Bit[11] is the Read Mode bit and should be set to ‘0’ for TOR reads. The Read Mode bit can alternatively be set to ‘1’ to read the ‘Core ID’ (with associated valid bit as shown in Figure 2-40) that points to the first core that asserted the IERR. In this case bits [10:0] of the parameter field are ignored. The ‘Core ID’ read may not return valid data until at least 1 mS after the IERR assertion.

Figure 2-40. Caching Agent TOR Read Data

31						0
	Cbo TOR Data
	Read Mode (bit 11) = ‘0’
		4	3	2	0
31
	RESERVED		Valid		Core ID
			bit
	Read Mode (bit 11) = ‘1’

Note: Reads to caching agents that are not enabled will return all zeroes. Refer to the debug handbook for details on methods to interpret the crash dump results using the Cbo TOR data shown in Figure 2-40.

2.5.2.6.31Thermal Margin Read

This service allows the PECI host to read the margin to the processor thermal profile or load line. Thermal margin data is returned in the format shown in Figure 2-41with a sign bit, an integer part and a fractional part. A negative thermal margin value implies that the processor is operating in violation of its thermal load line and may be indicative of a need for more aggressive cooling mechanisms through a fan speed increase or other means. This PECI service will continue to return valid margin values even when the processor die temperature exceeds Tjmax.

Figure 2-41. DTS Thermal Margin Read

31	16	15	14	6	5	0
	RESERVED	Sign		Thermal Margin		Thermal Margin
		Bit		(Integer Value)		(Fractional Value)

Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families	59
Datasheet Volume One