4th Gen Intel Xeon Scalable Processors Codename Sapphire Rapids
NDA Specification Update
Component Identification via Programming Interface
The 4th Gen Intel® Xeon® Scalable Processors stepping can be identified by the following register contents:
| Reserved | Extended Family1 | Extended Model2 | Reserved | Processor Type3 | Family Code4 | Model Number5 | Stepping ID6 |
|---|---|---|---|---|---|---|---|
| 31:28 | 27:20 | 19:16 | 15:13 | 12:12 | 11:8 | 7:4 | 3:0 |
| 00000000b | 0b | Varies per stepping |
- The Extended Family, bits [27:20] are used in conjunction with the Family Code, specified in bits [11:8], to indicate whether the processor belongs to the Intel386™, Intel486™, Pentium®, Pentium® Pro, Pentium® 4, Intel® Core™ processor families, Intel® Core™ ix families, and Intel® Xeon® processor families.
- The Extended Model, bits [19:16] in conjunction with the Model Number, specified in bits [7:4], are used to identify the model of the processor within the processor’s family.
- The Processor Type, specified in bit [12] indicates whether the processor is an original OEM processor, an Intel® OverDrive processor, or a dual processor (capable of being used in a dual processor system).
- The Family Code corresponds to bits [11:8] of the EDX register after RESET, bits [11:8] of the EAX register after the CPUID instruction is executed with a 1 in the EAX register, and the generation field of the Device ID register accessible through Boundary Scan.
- The Model Number corresponds to bits [7:4] of the EDX register after RESET, bits [7:4] of the EAX register after the CPUID instruction is executed with a 1 in the EAX register, and the model field of the Device ID register accessible through Boundary Scan.
- The Stepping ID in bits [3:0] indicates the revision number of that model. See Table: Component Identification via Registers for the processor stepping ID number in the CPUID information.
When EAX is set to a value of ‘1,’ the CPUID instruction returns the Extended Family, Extended Model, Processor Type, Family Code, Model Number, and Stepping ID together referred as the processor signature value, in the EAX register. Note that after reset, the EDX processor will report the processor signature value in both the EDX and the EAX registers.
Cache and TLB descriptor parameters are provided in the EAX, EBX, ECX, and EDX registers after the CPUID instruction is executed with a 2 in the EAX register.