628 AMD Geode™ LX Processors Data Book
Instruction Set
33234H
Table 8-18. CPUID Instruction Codes with EAX = 00000000
Register
Reset
Value Description Comment
EAX[31:28] 0x0 Reserved
EAX[27:20] 0x00 Extended Family
EAX[19:16] 0x00 Extended Model
EAX[15:12] 0x0 Reserved
EAX[11:8] 0x5 Processor/Instruction Family
EAX[7:4] 0xA Processor Model
EAX[3:0] 0x2 Processor Stepping May change with CPU revision
EBX[31:24] 0x00 Initial local APCI physical ID
EBX[23:16] 0x00 Reserved
EBX[15:08] 0x04 CLFLUSH cache line size in QWORD - 8 byte
increments
EBX[7:0] 0x00 8-bit brand ID
EDX[31:27] 0000 Reserved
EDX[26] 0 XMM2. Streaming SIMD Extensions Not supported
EDX[25] 0 XMM. Streaming SIMD Extensions Not suppor ted
EDX[24] 0 FXSR. Fast FP Save and Restore Not supported
EDX[23] 1 MMX™. MMX Instruction Set and Architecture
EDX[22:20] 000 Reserved
EDX[19} 1 CLFSH. CLFLUSH feature is supported
EDX[18] 0 PN. 96-Bit Serial Number Feature Not supported
EDX[17] 0 PSE36. 36-Bit Page Size Extensions Not supported
EDX[16] 0 PAT. Page Attribute Table Not supported
EDX[15] 1 CMOV. Conditional Move Instruction
EDX[14] 0 MCA. Machine Check Architecture Not supported
EDX[13] 1 PGE. Page Global Enable Feature
EDX[12] 0 MTRR. Memory Type Range Registers Not supported
EDX[11] 1 SEP. Sysenter/Sysexit Instruction
EDX[10] 0 Reserved
EDX[9] 0 APIC. Advanced Programmable Interrupt Not supported
EDX[8] 1 CX8. Compare Exchange (CMPXCHG8B)
Instruction
EDX[7] 0 MCE. Machine Check Exception Not supported
EDX[6] 0 PAE. Page Address Extension Not supported
EDX[5] 1 MSR. Model Specific Registers via
RDMSR/WRMSR Instructions
EDX[4] 1 TSC. Time Stamp Counter and RDTSC
Instruction
EDX[3] 1 PSE. 4 MB Page Size Extension
EDX[2] 1 DE. Debugging Extension