Instruction Set (Continued)
8.2.2.3 CPUID Instruction with
8.2.2.4 CPUID Instruction with EAX = 80000005h
Extended function 80000005h (EAX = 80000005h) of the
CPUID instruction returns information about the TLB and
L1 cache to be looked up in a lookup table. Refer to Table
8-25.
EAX = 80000002h, 80000003h, 80000004h
Extended functions 80000002h through 80000004h (EAX
= 80000002h, EAX = 80000003h, EAX = 80000004h) of
the CPUID instruction returns an ASCII string containing
the name of the current processor. These functions elimi-
nate the need to look up the processor name in a lookup
table. Software can simply call these functions to obtain
the name of the processor. The string may be 48 ASCII
characters long, and is returned in little endian format. If
the name is shorter than 48 characters long, the remain-
ing bytes will be filled with ASCII NUL characters (00h).
Table 8-25. Standard CPUID with
EAX = 80000005h
Returned
Register
Contents
Description
Reserved
EAX
EBX
--
xx xx 70 xxh TLB is 32 entry, 4-way set
associative, and has 4 KB
Pages.
Table 8-24. Official CPU Name
8000 0002h
8000 0003h
EAX CPU
Name 5
EBX CPU
Name 6
ECX CPU
Name 7
EDX CPU
Name 8
8000 0004h
EBX
xx xx xx 01h The CPUID instruction needs
to be executed only once with
an input value of 02h to retrieve
complete information about the
cache and TLB.
EAX CPU
Name 1
EAX CPU
Name 9
EBX CPU
Name 2
EBX CPU
Name 10
ECX
EDX
xx xx xx 80h L1 cache is 16 KB, 4-way set
associated, and has 16 bytes
per line.
ECX CPU
Name 3
ECX CPU
Name 11
EDX CPU
Name 4
EDX CPU
Name 12
--
Reserved
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