Volume 3: General-Purpose and System Instructions - Stanford ...

Volume 3: General-Purpose and System Instructions - Stanford ... Volume 3: General-Purpose and System Instructions - Stanford ...

scs.stanford.edu
from scs.stanford.edu More from this publisher
13.07.2015 Views

AMD64 Technology 24594 Rev. 3.10 February 2005Table 3-8 on page 130 gives an example of the return values and their equivalentASCII characters for a processor with the following name string:AMD Athlon(tm) processorTable 3-8.Processor Name String ExampleFunction Register Return Value ASCII CharactersEAX 2044_4D41h “space D M A”8000_0002hEBX 6C68_7441h “l h t A”ECX 7428_6E6Fh “t ( n o”EDX 7020_296Dh “p space ) m”EAX 6563_6F72h “e c o r”8000_0003h8000_0004hEBX 726F_7373h “r o s s”ECX0000_0000hEDX0000_0000hEAX0000_0000hEBX0000_0000hECX0000_0000hEDX0000_0000hExtended Function8000_0005h: L1Cache and TLBInformationCPUID extended functions 8000_0005h and 8000_0006h provide cache and TLBinformation. These functions are useful to diagnostic software that displaysinformation about the system and the configuration of the processor implementation,including cache size and organization. For more information about the TLB and onchipcaches, see “Translation-Lookaside Buffer (TLB)” in Volume 2 and “MemoryCaches” in Volume 2.Extended function 8000_0005h returns information about the TLBs and L1 cachesintegrated on the processor. Tables 3-9, 3-10, 3-11, and 3-12, all on page 131, show theregister formats for the information returned by function 8000_0005h.In these tables, the associativity field is encoded as follows:• 00h—Reserved.130 CPUID

24594 Rev. 3.10 February 2005 AMD64 Technology• 01h—Direct mapped.• 02h through FEh—The value represents the actual associativity. For example, avalue of 04h indicates 4-way associativity.• FFh—Fully associative.Table 3-9.RegisterCPUID TLB Bits for 2-Mbyte and 4-Mbyte Pages (Extended Function 8000_0005—EAX)Data TLBInstruction TLBAssociativity Number of Entries 1 Associativity Number of Entries 1EAX Bits 31–24 Bits 23–16 Bits 15–8 Bits 7–0Note:1. The number of entries returned is the number of entries available for the 2-Mbyte page size. The 4-Mbyte pages may require two2-Mbyte entries, depending on the implementation, so the number of entries available for the 4-Mbyte page size would be onehalfthe returned value.Table 3-10.RegisterCPUID TLB Bits for 4-Kbyte Pages (Extended Function 8000_0005—EBX)Data TLBInstruction TLBAssociativity Number of Entries Associativity Number of EntriesEBX Bits 31–24 Bits 23–16 Bits 15–8 Bits 7–0Table 3-11.RegisterCPUID L1 Data Cache Bits (Extended Function 8000_0005—ECX)L1 Data CacheSize (Kbytes) Associativity Lines Per Tag Line Size (Bytes)ECX Bits 31–24 Bits 23–16 Bits 15–8 Bits 7–0Table 3-12.RegisterCPUID L1 Instruction Cache Bits (Extended Function 8000_0005—EDX)L1 Instruction CacheSize (Kbytes) Associativity Lines Per Tag Line Size (Bytes)EDX Bits 31–24 Bits 23–16 Bits 15–8 Bits 7–0CPUID 131

AMD64 Technology 24594 Rev. 3.10 February 2005Table 3-8 on page 130 gives an example of the return values <strong>and</strong> their equivalentASCII characters for a processor with the following name string:AMD Athlon(tm) processorTable 3-8.Processor Name String ExampleFunction Register Return Value ASCII CharactersEAX 2044_4D41h “space D M A”8000_0002hEBX 6C68_7441h “l h t A”ECX 7428_6E6Fh “t ( n o”EDX 7020_296Dh “p space ) m”EAX 6563_6F72h “e c o r”8000_0003h8000_0004hEBX 726F_7373h “r o s s”ECX0000_0000hEDX0000_0000hEAX0000_0000hEBX0000_0000hECX0000_0000hEDX0000_0000hExtended Function8000_0005h: L1Cache <strong>and</strong> TLBInformationCPUID extended functions 8000_0005h <strong>and</strong> 8000_0006h provide cache <strong>and</strong> TLBinformation. These functions are useful to diagnostic software that displaysinformation about the system <strong>and</strong> the configuration of the processor implementation,including cache size <strong>and</strong> organization. For more information about the TLB <strong>and</strong> onchipcaches, see “Translation-Lookaside Buffer (TLB)” in <strong>Volume</strong> 2 <strong>and</strong> “MemoryCaches” in <strong>Volume</strong> 2.Extended function 8000_0005h returns information about the TLBs <strong>and</strong> L1 cachesintegrated on the processor. Tables 3-9, 3-10, 3-11, <strong>and</strong> 3-12, all on page 131, show theregister formats for the information returned by function 8000_0005h.In these tables, the associativity field is encoded as follows:• 00h—Reserved.130 CPUID

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!